1. Basic Anatomy (Heart, Thorax, Osteology, Histology, Myology)
2. Physiology (Cardiovascular + Respiratory)
3. Biochemistry

---

B.Sc. Cardiac Technology - 3rd Year Paper I

Cardiac Catheterization Laboratory Basics

Complete Exam Preparation Guide

---

SECTION A: ESSAY QUESTIONS (10 Marks Each)

---

ESSAY 1: Coronary Angiography - Technique, Views, Catheters and Complications

---

1. Indications

• Stable angina not responding to medical therapy
• Unstable angina / Non-ST elevation MI (NSTEMI)
• ST elevation MI (STEMI) for primary PCI
• Pre-operative assessment before cardiac surgery
• Evaluation of valvular heart disease
• Assessment of coronary anomalies
• Positive stress test or stress echo

2. Catheters Used

• Catheters are 5F, 6F, or 7F in diameter
• Made of polyurethane or nylon
• Introduced via femoral artery (Judkins technique) or radial artery (Sones/transradial approach)

3. Vascular Access

• Femoral approach (Judkins): Seldinger technique through femoral artery; 6F sheath used commonly; arterial entry at femoral head level
• Radial approach (transradial): Preferred today; less bleeding, early ambulation; Allen's test done beforehand to check dual circulation

4. Manifold System

• Contrast syringe
• Pressure line (for pressure monitoring)
• Flush/saline line
• Waste/aspiration line

5. Angiographic Views - Left Coronary Artery

6. Angiographic Views - Right Coronary Artery

7. Contrast Agents

• Non-ionic agents preferred: Iohexol (Omnipaque), Iopamidol, Iodixanol (iso-osmolar)
• Usual volume: 5-8 mL per coronary injection; 30-40 mL for ventriculography
• Side effects: Contrast nephropathy, allergic reaction, osmotic effects

8. Assessment of Stenosis

• Severity graded as % diameter stenosis (visual estimate or QCA)
• Significant stenosis: ≥70% in major epicardial vessel; ≥50% in LM
• TIMI flow grade (0 to 3) used to describe flow

9. Complications

10. Radiation Protection

• Lead apron, thyroid shield, leaded glasses
• Keep distance from X-ray source (inverse square law)
• Minimize fluoroscopy time and cine runs
• Use pulsed fluoroscopy

---

ESSAY 2: Pressure Recording in Cardiac Catheterization - Systems, Waveforms, Gradients and Artifacts

Introduction

---

1. Pressure Recording Systems

• Catheter filled with saline connected via tubing to an external pressure transducer
• Transducer converts mechanical pressure to electrical signal
• Must be zeroed at mid-chest (phlebostatic axis)
• Advantages: Simple, cheap
• Disadvantages: Signal distortion due to resonance, damping; artifacts with air bubbles or clots

• Miniature transducer mounted at catheter tip
• Records pressure at actual site without tubing artefact
• Very accurate - used for research
• Disadvantages: Expensive, fragile

2. Normal Pressure Values

3. Pressure Waveforms

• a wave: Atrial contraction (absent in AF)
• c wave: Tricuspid/mitral valve closure (small, often merged with 'a')
• v wave: Ventricular systole with atria filling passively; giant v wave in MR/TR
• x descent: Atrial relaxation
• y descent: AV valve opening and ventricular filling

• Rapid rise during systole, fall during diastole
• LV end-diastolic pressure (LVEDP): Marker of LV function; elevated in heart failure

• Reflects left atrial pressure when balloon-tipped catheter is wedged in pulmonary capillary
• Used to assess LV filling pressure and diagnose pulmonary venous hypertension

4. Damping and Artifacts

• Causes: Air bubble, clot, kinked tubing, soft catheter
• Effect: Falsely low systolic, falsely high diastolic; blunted waveform

• Causes: Stiff catheter, long tubing, high natural frequency
• Effect: Falsely high systolic, falsely low diastolic; overshoot artifact

• In high-flow areas (PA, aorta); catheter tip movement generates spurious pressure changes
• Solution: Use catheter-tipped transducer or average multiple cycles

• Catheter slips out of wedge position, records RV pressure instead of PCWP
• Recognized by increased pulse pressure; correct by re-inflating balloon

5. Pressure Gradient Recording

• Two transducers used simultaneously (one each side of valve)
• Most accurate; used for aortic stenosis (LV vs. Ao) and mitral stenosis (LA vs. LV via transseptal)

• Non-simultaneous; peak LV pressure vs. peak Ao pressure recorded at different time points
• Convenient but overestimates physiological gradient because peaks don't occur simultaneously

• Single catheter slowly withdrawn across valve
• Used for aortic stenosis (LV to Ao pullback) and pulmonic stenosis (RV to PA pullback)
• Identifies level of obstruction (valvular vs. subvalvular vs. supravalvular)

6. Clinical Applications of Pressure Data

• Mitral stenosis: Mean transmitral gradient >5 mmHg; PCWP elevated; LA-LV diastolic gradient
• Aortic stenosis: Peak-to-peak LV-Ao gradient; severe if mean gradient >40 mmHg or valve area <1.0 cm²
• Pulmonary hypertension: mPAP ≥25 mmHg; Eisenmenger when pulmonary > systemic resistance
• Constrictive pericarditis: Equalization of diastolic pressures in all four chambers
• Cardiac tamponade: Equalization of RA, RV diastolic, and PCWP; "pulsus paradoxus"

---

ESSAY 3: Cardiac Output Determination - Methods, Principles and Clinical Significance

Introduction

---

1. Thermodilution Method (Most Common)

• Has proximal port (RA), distal port (PA), balloon port, thermistor (near tip)

1. 10 mL of cold (iced) or room-temperature saline injected rapidly into proximal (RA) port
2. Thermistor near tip measures temperature change over time in PA
3. Modified Stewart-Hamilton equation calculates CO:

CO = [V × (Tb - Ti) × K] / ∫ΔTb(t)dt

• V = injectate volume
• Tb = blood temperature
• Ti = injectate temperature
• K = computation constant
• ∫ΔTb = area under thermodilution curve

---

2. Fick Principle (Oxygen Consumption Method)

CO = O₂ consumption (mL/min) / [Arteriovenous O₂ difference (mL/L)]

• O₂ consumption measured by spirometry (or assumed as 125 mL/min/m²)
• AV O₂ difference = (Aortic O₂ content) - (Pulmonary artery O₂ content)
• O₂ content = Hb × 1.34 × O₂ saturation

• O₂ consumption = 250 mL/min
• Aortic sat = 98%, PA sat = 75%, Hb = 15 g/dL
• O₂ content difference = 15 × 1.34 × (0.98 - 0.75) = 4.63 mL/dL = 46.3 mL/L
• CO = 250 / 46.3 = 5.4 L/min

---

3. Indicator Dilution Method (Dye Dilution)

• Dye injected into RA or pulmonary artery
• Arterial blood sampled continuously from aorta
• Concentration-time curve plotted; area under curve used to calculate CO

CO = Dose of indicator (mg) / [Mean concentration × Duration of curve]

---

4. Shunt Detection and Calculation

Qp/Qs = (Aortic sat - Mixed venous sat) / (Pulmonary vein sat - PA sat)

• Normal = 1:1
• Qp/Qs >1.5: Significant left-to-right shunt; consider closure
• Qp/Qs >2.0: Large shunt; surgery/device closure indicated

---

5. Clinical Significance

---

SECTION B: SHORT NOTES (5 Marks Each)

---

1. Types of Catheters and Their Uses

• Diagnostic catheters: Judkins Left/Right, Amplatz, Multipurpose, Pigtail
• Guiding catheters: For PCI; provide back-up support (EBU, XB, JL, JR)
• Special purpose: Balloon-tipped (Swan-Ganz), EP catheters (ablation, mapping), IABP catheters, intravascular ultrasound (IVUS) catheters

---

2. Sterilization Methods in Cath Lab

• Single-use (disposable) catheters should never be resterilized
• High-level disinfection vs. sterilization: sterilization kills ALL organisms including spores
• Prion safety requires special protocols

---

3. Left Ventriculography - Technique, Catheters and Views

• LV systolic function (EF calculation)
• Wall motion abnormalities (regional in IHD)
• Mitral regurgitation (severity grading)
• LV thrombus, VSD

• Pigtail catheter (most common): Multiple side holes prevent high jet injury
• Alternatively: NIH catheter, Berman catheter

• Catheter advanced retrogradely across aortic valve into LV
• Contrast (30-40 mL) injected at 10-15 mL/sec using power injector
• Injector pressure: 600-900 psi

• RAO 30°: Best for anterior and inferior wall; MR jet visible to LA; standard view
• LAO 60° (cranial): Interventricular septum viewed en face; septal motion; lateral wall

• EF = (EDV - ESV) / EDV × 100
• Normal EF >55%
• Regional wall motion: Normal, hypokinesis, akinesis, dyskinesis

---

4. Intra-cardiac Pressures and Normal Values

• RA: Mean 0-8 mmHg; a wave 2-10, v wave 2-10
• RV: Systolic 15-30 / Diastolic 0-8 mmHg
• PA: Systolic 15-30 / Diastolic 8-15 / Mean 10-20 mmHg
• PCWP: Mean 6-12 mmHg

• LV: Systolic 100-140 / LVEDP 5-12 mmHg
• Aorta: Systolic 100-140 / Diastolic 60-90 / Mean 70-105 mmHg

• Elevated LVEDP (>18 mmHg): LV failure
• Elevated PCWP (>18 mmHg): Pulmonary venous hypertension; risk of pulmonary edema
• Mean PA >25 mmHg: Pulmonary arterial hypertension
• Equalization of diastolic pressures: Constrictive pericarditis or tamponade

---

5. Radiation Protection in Cath Lab

• Lead apron: 0.35-0.5 mm lead equivalent; protects trunk
• Thyroid collar: Protects thyroid
• Lead glasses: Protects lens (prevents radiation cataract)
• Lead acrylic screen (ceiling-mounted or table-mounted): Scatter protection

• Increase source-to-image distance
• Decrease image intensifier-to-patient distance
• Collimate beam to area of interest
• Use pulsed fluoroscopy (7.5 or 15 frames/sec instead of 30)

• Occupational: 20 mSv/year (averaged over 5 years)
• Pregnant worker: 1 mSv to fetus during pregnancy

---

6. Oxygen Dilution Method (Fick Principle) - Shunts and CO

• Fick principle: CO = O₂ consumption / AV O₂ difference
• Most accurate method; gold standard
• Used for shunt calculations in congenital heart disease
• Requires blood samples from PA, Ao, and O₂ consumption measurement
• Shunt detected by saturation step-up at level of defect
• Qp:Qs ratio quantifies magnitude of shunt

---

7. Image Intensifier and Table Movement

• Converts X-ray to visible light image
• Components: Input phosphor (CsI) → photocathode → electronic focusing → output phosphor → TV camera
• Modern systems use flat panel detectors (FPD) instead of II; better image quality, less distortion

• Cranial/Caudal: Tilts toward patient's head or feet; changes the angle of view along the long axis of body
• LAO/RAO: Rotates left or right around patient; changes lateral viewing angle
• Panning: Moves II over the patient to center over region of interest

• Longitudinal: Head-to-foot movement (to follow catheter from groin to heart)
• Lateral: Left-right movement
• Height adjustment: Raises/lowers patient to optimize geometry
• Tilt (Trendelenburg/Reverse): Head-down or head-up

• Cine images stored on digital archive (DICOM format)
• Can be replayed frame-by-frame or in real-time
• Used for review, reporting, and comparison with previous studies

---

8. Electrophysiology Study (EP Study) - Basics

• High right atrium (HRA) catheter
• His bundle catheter
• Coronary sinus (CS) catheter
• Right ventricular apex (RVA) catheter

• PA interval: 25-55 ms (intra-atrial conduction)
• AH interval: 55-130 ms (AV nodal conduction)
• HV interval: 35-55 ms (His-Purkinje conduction)

• Programmed electrical stimulation (PES) using extra stimuli (S1, S2, S3)
• Burst pacing to induce tachycardia

• Thermal energy (RF current) delivered via ablation catheter tip
• Tip heats to 50-60°C; creates controlled necrotic lesion destroying arrhythmia circuit
• Used for: SVT, WPW, atrial flutter, atrial fibrillation, VT

---

SECTION C: SHORT ANSWERS (3 Marks Each)

---

---

---

• TIMI 0: No flow (complete occlusion)
• TIMI 1: Minimal flow; contrast enters but doesn't fill distal vessel
• TIMI 2: Partial flow; slow filling of entire vessel
• TIMI 3: Normal flow; brisk filling and washout of entire vessel

---

---

---

---

• Ionic: High-osmolality; cheaper; more side effects (pain, arrhythmias); e.g., diatrizoate (Hypaque)
• Non-ionic (low-osmolality): Safer; less pain; preferred today; e.g., Iohexol (Omnipaque), Iopamidol, Iodixanol (iso-osmolar, best for renal impairment)

---

---

---

---

QUICK REFERENCE: High-Probability Exam Topics Summary

---

Exam pattern reminder: 3 Essays × 10 = 30 marks | 8 Short Notes × 5 = 40 marks | 10 Short Answers × 3 = 30 marks | Total = 100 marks

• 10 mark = 2-3 pages எழுதணும், maximum marks வாங்கணும்
• 5 mark = 1 page போதும்
• 3 mark = half page போதும்

---

✅ Exam Writing Strategy - எவ்வளவு எழுதணும்?

---

📝 10 Mark Question (Essay)

• 4-5 points with explanation = Full marks
• 2-3 pages (handwriting normal size)
• Time: ~15-18 minutes

1. Definition / Introduction  (2-3 lines)
2. Point 1 with explanation   (3-4 lines)
3. Point 2 with explanation   (3-4 lines)
4. Point 3 with explanation   (3-4 lines)
5. Point 4 with explanation   (3-4 lines)
6. Diagram (if possible)      (+bonus marks)
7. Conclusion                 (1-2 lines)

Definition: Coronary angiography is the gold standard invasive test to visualize coronary arteries using contrast dye under X-ray guidance.

Indications:

• Chest pain not responding to medicines
• Before heart surgery
• Positive stress test

Catheters Used:

• Judkins Left (JL 4.0) - for Left coronary
• Judkins Right (JR 4.0) - for Right coronary

Views:

• RAO Caudal - LM, LCx seen
• LAO Cranial - LAD seen
• RAO 30° - RCA distal seen

Complications:

• Contrast allergy
• Arterial hematoma
• Coronary dissection

Conclusion: Coronary angiography helps plan further treatment like PTCA or CABG.

---

📝 5 Mark Question (Short Note)

• 3-4 points = Full marks
• 1 page (or 15-20 lines)
• Time: ~8-10 minutes

1. One-line definition
2. Point 1 (2-3 lines)
3. Point 2 (2-3 lines)
4. Point 3 (2-3 lines)
5. One diagram or table (optional but good)

Definition: Measures taken to minimize X-ray exposure in cath lab (ALARA principle).

Methods:

1. Distance - Stand far from X-ray source
2. Shielding - Lead apron, thyroid collar, lead glasses
3. Time - Minimize fluoroscopy time
4. Dosimeter - Wear TLD badge to monitor dose

Safe dose limit: 20 mSv/year for cath lab staff.

---

📝 3 Mark Question (Short Answer)

• 3 points (one line each) = Full marks
• Half page (6-8 lines)
• Time: ~4-5 minutes

1. Definition (1 line)
2. Point 1
3. Point 2
4. Point 3

Allen Test is done before radial artery access.

1. Compress both radial and ulnar arteries → hand blanches
2. Release radial artery pressure
3. If hand turns pink within 10 seconds → safe to use radial artery

---

🎯 Key Rule - எல்லா question-க்கும்:

• ✅ Headings போடுங்க (examiner-க்கு easy to read)
• ✅ Numbered points use பண்ணுங்க
• ✅ One simple diagram போட்டா bonus marks
• ✅ Definition + Points + Conclusion = guaranteed marks
• ❌ Long paragraphs வேண்டாம் - points போதும்

• 10 mark = 3-4 pages எழுதணும்
• 5 mark = 2-3 pages எழுதணும்
• 3 mark = half page எழுதணும்

---

3rd Year Paper I - Cardiac Catheterization Laboratory Basics

Exam-Ready Answers (Exact Length Format)

---

10 MARK ANSWERS (3-4 Pages Length)

---

Q1. Coronary Angiography - Technique, Catheters, Views and Complications

Introduction

---

Indications

1. Stable angina not adequately controlled with medical therapy
2. Unstable angina / NSTEMI (Non-ST Elevation Myocardial Infarction)
3. STEMI (ST Elevation Myocardial Infarction) - for primary PCI
4. Positive treadmill test or stress echocardiography
5. Pre-operative evaluation before valve surgery or CABG
6. Assessment of coronary anomalies
7. Suspected Prinzmetal (variant) angina
8. Follow-up after previous PTCA or CABG

---

Contraindications

1. Severe contrast allergy (relative - can pre-medicate)
2. Severe renal failure (relative - use iso-osmolar contrast + hydration)
3. Uncontrolled hypertension or heart failure
4. Active bleeding or coagulopathy
5. Patient refusal or non-cooperation

---

Pre-procedure Preparation

1. Written informed consent
2. NPO (nil by mouth) for 4-6 hours
3. Blood investigations: CBC, RFT, coagulation profile, serum creatinine
4. ECG and echocardiography review
5. IV access secured (18G cannula)
6. Pre-medication: Antihistamines if contrast allergy history
7. Heparin 3000-5000 units IV after sheath insertion
8. Patient positioned on cath table; groin/wrist shaved and cleaned

---

Vascular Access

• Right femoral artery punctured using Seldinger technique at the level of femoral head
• 6F arterial sheath inserted
• Catheter advanced through aorta to coronary ostia under fluoroscopy
• Advantage: Larger vessel, easy access, good for complex procedures
• Disadvantage: Patient must lie flat for 4-6 hours post-procedure; bleeding risk

• Allen test done first to confirm dual (ulnar) circulation
• Right radial artery punctured at wrist
• 5F or 6F sheath inserted
• Advantage: Less bleeding, early ambulation, patient comfort, less vascular complications
• Disadvantage: Learning curve; vessel spasm possible

1. Artery punctured with needle
2. Guidewire passed through needle
3. Needle removed
4. Dilator + sheath passed over wire
5. Wire and dilator removed; sheath stays in vessel

---

Catheters Used

• Catheters made of polyurethane or braided nylon
• Size in French: 1 French = 0.33 mm diameter
• Pre-shaped curves allow selective engagement of ostia

---

The Manifold System

1. Contrast syringe
2. Pressure transducer line (for pressure monitoring)
3. Saline flush line
4. Waste/aspiration line

---

Angiographic Views - Left Coronary System

---

Angiographic Views - Right Coronary Artery

---

Contrast Agents

1. Ionic (High-osmolality): Older agents; painful; more side effects; e.g., Diatrizoate (Hypaque)
2. Non-ionic (Low-osmolality): Safe, painless, preferred; e.g., Iohexol (Omnipaque), Iopamidol
3. Iso-osmolar: Safest for kidney patients; e.g., Iodixanol (Visipaque)

• Usual volume: 5-8 mL per coronary injection; 30-40 mL for LV gram
• Risk: Contrast nephropathy, allergy, osmotic effects

---

Stenosis Assessment

• Graded as percentage diameter stenosis by visual estimation or Quantitative Coronary Analysis (QCA)
• Significant stenosis: ≥70% in major vessel; ≥50% in Left Main
• TIMI flow grades:
  • TIMI 0: No flow
  • TIMI 1: Minimal flow only
  • TIMI 2: Partial/slow flow
  • TIMI 3: Normal flow

---

Complications

---

Radiation Protection in Cath Lab

• Lead apron (0.5 mm Pb equivalent) - mandatory
• Thyroid collar
• Lead glasses (prevent radiation cataract)
• Ceiling-mounted lead acrylic shield
• Keep maximum distance from X-ray tube
• Minimize fluoroscopy time (use pulsed fluoroscopy 7.5 fps)
• Use last-image hold instead of cine when possible
• Wear TLD dosimeter badge - dose limit 20 mSv/year

---

Conclusion

---

---

Q2. Cardiac Output Determination - Thermodilution and Fick Principle

Introduction

• Cardiac Output (CO): 4-8 litres per minute
• Cardiac Index (CI) = CO / Body Surface Area = 2.4-4.0 L/min/m²
• Stroke Volume (SV) = CO / Heart Rate = 60-100 mL/beat

---

Methods of Cardiac Output Measurement

---

Method 1: Thermodilution Method (Most Commonly Used)

• 4-lumen catheter, 7F size
• Proximal port (RA) - for cold saline injection and CVP monitoring
• Distal port (PA) - for PA pressure and PCWP measurement
• Balloon port - for balloon inflation to float catheter and wedge
• Thermistor - located 4 cm from tip; measures temperature changes in PA

1. Swan-Ganz catheter inserted via internal jugular or subclavian vein
2. Balloon inflated with 1.5 mL air; catheter "floats" with blood flow through RA → RV → PA
3. Position confirmed by pressure waveform changes (RA → RV → PA → PCWP)
4. Exactly 10 mL of cold (iced 0-4°C) or room temperature saline drawn in syringe
5. Saline injected rapidly (within 4 seconds) through proximal (RA) port
6. Thermistor at distal end records temperature change over time
7. CO computer integrates the area under temperature-time curve
8. Minimum 3 measurements taken; values within 10% of each other are averaged

CO = [V × (Tb - Ti) × K] / Area under thermodilution curve

• V = volume of injectate (10 mL)
• Tb = blood temperature (°C)
• Ti = temperature of injectate (°C)
• K = computation constant (accounts for catheter dead space, specific heat)
• Area = integral of temperature change over time

• Normal CO: Smooth curve, rapid upstroke, gradual return to baseline
• Low CO: Slow upstroke, prolonged curve, large area under curve
• High CO: Rapid upstroke and downstroke, small area under curve
• Tricuspid regurgitation: Irregular, prolonged curve (injectate recirculates) → falsely HIGH CO reading
• Intracardiac shunt (L→R): Falsely high CO reading

1. Bedside use - no arterial sampling needed
2. Can be repeated multiple times
3. Quick results (within minutes)
4. Widely available in most ICUs and cath labs

1. Inaccurate in tricuspid regurgitation
2. Inaccurate in intracardiac shunts
3. Error with improper injection technique (slow injection)
4. Requires PA catheter insertion (invasive; risk of pneumothorax, arrhythmia)
5. Inaccurate in very low cardiac output states

---

Method 2: Fick Principle (Gold Standard)

CO = Oxygen Consumption (VO₂) / Arteriovenous Oxygen Content Difference (C(a-v)O₂)

CO = VO₂ (mL/min) / [CaO₂ - CvO₂] (mL/L)

• VO₂ = oxygen consumption measured by spirometry or assumed (125 mL/min/m²)
• CaO₂ = arterial O₂ content = Hb × 1.34 × SaO₂ × 10
• CvO₂ = mixed venous O₂ content = Hb × 1.34 × SvO₂ × 10
• SaO₂ from aorta; SvO₂ from pulmonary artery (mixed venous)

• O₂ consumption = 250 mL/min
• Hemoglobin = 15 g/dL
• Aortic saturation = 98%
• PA (mixed venous) saturation = 75%
• CaO₂ = 15 × 1.34 × 0.98 × 10 = 196.8 mL/L
• CvO₂ = 15 × 1.34 × 0.75 × 10 = 150.8 mL/L
• AV difference = 196.8 - 150.8 = 46 mL/L
• CO = 250 / 46 = 5.4 L/min (Normal)

• Arterial sample: Aorta or femoral artery
• Venous sample: Pulmonary artery (true mixed venous blood)
• Not from RA or RV - these are not properly mixed

1. Most accurate - true gold standard
2. Valid in presence of intracardiac shunts
3. Valid in arrhythmias and tricuspid regurgitation
4. Can simultaneously calculate shunt ratio (Qp:Qs)

1. Requires measurement of O₂ consumption (spirometry in steady state)
2. Assumed VO₂ introduces error
3. Multiple blood samples required
4. Requires patient in stable, steady state (not valid in acute hemodynamic changes)
5. Time-consuming

---

Method 3: Indicator Dye Dilution Method

CO = Amount of dye injected / (Mean concentration × Duration of curve)

---

Method 4: Pulse Doppler Method

• Doppler echocardiography used to measure velocity of blood flow across aortic valve
• CO = Stroke Volume × Heart Rate
• Stroke Volume = Cross-sectional area of LVOT × Velocity Time Integral (VTI)
• Non-invasive; can be repeated bedside
• Less accurate than Fick but useful for monitoring trends

---

Shunt Detection and Calculation

Qp/Qs = (SaO₂ - SvO₂) / (SpvO₂ - SpaO₂)

• Normal = 1:1

• 1.5:1 = Significant shunt; consider closure

• 2.0:1 = Large shunt; intervention indicated

---

Clinical Significance of Cardiac Output

---

Conclusion

---

---

Q3. Pressure Recording in Cardiac Catheterization - Systems, Waveforms, Gradients, Normal Values and Artifacts

Introduction

---

Pressure Recording Systems

1. Intravascular catheter
2. Saline-filled pressure tubing (non-compliant, rigid)
3. Stopcock/manifold
4. External strain-gauge pressure transducer
5. Amplifier and display monitor

• Pressure wave travels from catheter tip through saline-filled column to transducer
• Transducer diaphragm deflects proportional to pressure
• Strain gauge converts mechanical deflection to electrical signal
• Signal amplified and displayed as pressure waveform

---

• Miniature piezoelectric or strain-gauge transducer mounted directly at the catheter tip
• Eliminates all errors caused by fluid-filled tubing
• Records pressure at the exact site of measurement
• Gold standard for research and dP/dt (rate of pressure rise) measurement
• Disadvantage: Expensive, fragile, not used routinely

---

Normal Intracardiac Pressure Values

---

Pressure Waveforms

• a wave: Due to atrial contraction (end of diastole)
  • Absent in atrial fibrillation (no organized atrial contraction)
  • Cannon a wave: When atrium contracts against closed AV valve (complete heart block, junctional rhythm)
• c wave: Small deflection due to AV valve closure (mitral/tricuspid closure); often not visible
• v wave: Passive atrial filling during ventricular systole (when AV valves are closed)
  • Giant v wave in mitral regurgitation (large blood volume regurgitating into LA during systole)
  • Giant v wave in tricuspid regurgitation (RA)
• x descent: Atrial relaxation + downward displacement of AV valve during ventricular systole
  • Absent or reversed (x' rise) in cardiac tamponade
• y descent: AV valve opens; blood flows from atrium to ventricle in early diastole
  • Steep y descent: Constrictive pericarditis (rapid early filling)
  • Blunted y descent: Cardiac tamponade (restricted filling)

---

• Rapid pressure rise during isovolumetric contraction
• Peak during ventricular systole
• Rapid fall during isovolumetric relaxation
• Low, flat baseline during diastole

• Measured at end of diastole just before QRS complex
• Normal: 5-12 mmHg
• Elevated LVEDP (>18 mmHg): Indicates LV failure, reduced compliance, fluid overload

---

• Rapid rise during ventricular ejection
• Peak = Systolic pressure
• Dicrotic notch = Aortic/pulmonic valve closure (end of systole)
• Gradual fall during diastole
• Nadir = Diastolic pressure

---

• Obtained when balloon-tipped catheter is inflated and advanced until it "wedges" in a small pulmonary artery
• Reflects left atrial pressure (with slight time delay)
• Normal: 6-12 mmHg
• PCWP >18 mmHg: Pulmonary venous hypertension; risk of pulmonary edema
• PCWP >25 mmHg: Pulmonary edema
• Used to differentiate cardiac vs. non-cardiac pulmonary edema (ARDS: PCWP normal or low)

---

Artifacts in Pressure Recording

• Causes: Air bubble in tubing, blood clot at catheter tip, kinked tubing, soft/compliant tubing, loose connections
• Effect: Blunted, sluggish waveform; systolic pressure falsely LOW; diastolic pressure falsely HIGH; narrow pulse pressure
• Solution: Flush catheter briskly; check for air bubbles; check connections

• Causes: Stiff catheter, short rigid tubing, high natural frequency of system
• Effect: Overshoot artifact; systolic pressure falsely HIGH; diastolic pressure falsely LOW; wide pulse pressure
• Solution: Add in-line damping device; use appropriate length tubing

• Caused by physical movement of catheter tip in high-flow vessels (PA, aorta)
• Catheter tip moves during cardiac contraction, producing spurious pressure changes
• Solution: Use catheter-tipped transducer; average over multiple cycles

• PCWP catheter slips back from wedge position into main PA; records RV-like pattern
• Recognized by sudden increase in pulse pressure and loss of typical PCWP morphology
• Solution: Re-inflate balloon; advance catheter to re-wedge

• Electrical hum from equipment
• Solution: Proper grounding of equipment; electrical isolation

---

Pressure Gradient Recording

• Two transducers used simultaneously, one on each side of valve
• Most accurate method
• Used for: Aortic stenosis (LV + Aorta), Mitral stenosis (LA via transseptal + LV)

• Non-simultaneous method using single catheter
• Peak LV pressure minus peak Aortic pressure recorded at different time points
• Convenient but overestimates gradient (peaks don't occur at the same time physiologically)

• Catheter slowly withdrawn across valve while continuously recording pressure
• Shows pressure drop as catheter crosses the valve
• Used for: Aortic stenosis (LV → Ao), Pulmonic stenosis (RV → PA), Coarctation (distal → proximal Ao)

---

Clinical Applications

---

Conclusion

---

5 MARK ANSWERS (2-3 Pages Length)

---

1. Radiation Protection in Cardiac Catheterization Laboratory

Introduction

---

Sources of Radiation in Cath Lab

1. Primary X-ray beam (direct beam from X-ray tube)
2. Scattered radiation from patient's body (main source for staff)
3. Leakage radiation from X-ray tube housing

---

Protective Measures

• Radiation intensity decreases with the square of distance from source
• Doubling distance reduces dose to one-fourth (inverse square law)
• Staff should stand as far as possible from X-ray tube during cine runs
• Control room with lead-glass window provides maximum protection

• Lead apron: 0.35-0.5 mm lead equivalent; must cover front and sides of torso; protects liver, gonads, bone marrow
• Thyroid collar: Protects thyroid gland (highly radiation-sensitive)
• Lead glasses: Protects eye lens; prevents radiation-induced cataract (dose limit to lens: 20 mSv/year)
• Lead gloves: For staff whose hands are near beam (rarely needed)
• Ceiling-mounted lead acrylic shield: Large transparent shield between patient and staff; reduces scatter by 90%
• Table-mounted side shields: Additional scatter protection at table level

• Reduce fluoroscopy "on" time as much as possible
• Use "last image hold" feature - freezes last fluoroscopy image on screen without live radiation
• Use cine imaging only when essential (much higher dose than fluoroscopy)
• Plan procedure before starting; avoid unnecessary runs

• Pulsed fluoroscopy: Use 7.5 or 15 frames/sec instead of continuous 30 fps - reduces dose by 50-75%
• Collimate beam: Use lead collimators/shutters to restrict beam to area of interest
• Decrease magnification: Higher magnification = higher dose; use only when necessary
• Increase Source-to-Image Distance (SID): Increases distance from tube to patient; reduces skin dose
• Decrease Image Intensifier-to-Patient Distance: Move II as close to patient as possible; reduces dose
• Remove grid when not needed: In paediatric patients; reduces dose by 50%

• All cath lab staff must wear TLD (Thermoluminescent Dosimeter) badge
• Badge worn at collar level outside lead apron (or waist level under apron)
• Dose reports reviewed monthly
• Pregnant staff: Additional fetal dosimeter; dose limit 1 mSv to fetus throughout pregnancy

• Whole body: 20 mSv/year (averaged over 5 years)
• No single year should exceed 30 mSv
• Lens of eye: 20 mSv/year
• Extremities and skin: 500 mSv/year
• Pregnant worker: 1 mSv to fetus during pregnancy

---

Special Situations

• Complex PCI / structural interventions: Higher radiation dose - increased attention to protection
• Obese patients: Higher scatter; worse image quality tempts operator to increase dose
• Paediatric patients: Extra protection; gonads shielded

---

Conclusion

---

2. Sterilization Methods in Cardiac Catheterization Laboratory

Introduction

---

Methods of Sterilization

• Temperature: 121°C at 15 psi for 15-20 minutes; or 134°C at 30 psi for 3 minutes
• Mechanism: Moist heat coagulates and denatures microbial proteins
• Used for: Metal instruments, surgical drapes, gowns, gloves, some plastics
• Advantages: Reliable, fast, inexpensive, no toxic residue, kills all organisms including spores
• Disadvantages: Cannot use for heat-sensitive or moisture-sensitive materials; damages some plastics and rubber

• Temperature: 37-60°C; exposure time 2-6 hours; then aeration for 24-48 hours to remove toxic residue
• Mechanism: Alkylation of microbial DNA and proteins
• Used for: Catheters, guidewires, plastic tubing, electronic devices, pacemakers - all heat-labile items
• Advantages: Penetrates packaging; effective at low temperature; sterilizes all heat-sensitive items
• Disadvantages: Ethylene oxide is toxic, carcinogenic; requires long aeration period; special chamber needed; expensive

• Exposure time: 20 minutes for high-level disinfection; 10 hours for sterilization
• Mechanism: Cross-links proteins in microorganisms
• Used for: Endoscopes, reusable equipment that cannot be autoclaved
• Advantages: Effective against bacteria, fungi, viruses, mycobacteria
• Disadvantages: Irritating to skin, eyes, respiratory tract; not a true sterilant at routine immersion times; must be rinsed thoroughly before use

• Temperature: 160°C for 2 hours; or 180°C for 30 minutes
• Mechanism: Oxidation and protein denaturation
• Used for: Metal instruments, glassware, oils, powders
• Advantages: Simple; no moisture damage; good penetration
• Disadvantages: Slow process; cannot use for plastics, rubber, or heat-sensitive items

• Ionizing radiation used in industrial/factory setting
• Used for: Single-use disposable catheters, guidewires, stents - sterilized at manufacturer
• Advantages: Cold process; penetrates packaging; no residue
• Disadvantages: Not available in hospital setting; may degrade some plastics; expensive equipment

• Low temperature (45-50°C); 45-75 minute cycle
• Mechanism: Free radicals destroy microorganisms
• Used for: Delicate instruments, flexible endoscopes, catheters that cannot withstand ETO
• Advantages: Fast; no toxic residue; safe for staff
• Disadvantages: Cannot use with liquids or cellulose-based materials; expensive

---

Catheter Cleaning Protocol

1. Flush catheter immediately after use with water
2. Wipe external surface with enzymatic cleaner
3. Inspect for damage (cracks, kinks) - discard if damaged
4. Single-use catheters must NEVER be resterilized - this is illegal and dangerous (protein contamination, structural weakness, prion risk)
5. Reusable catheters sent for sterilization as per protocol

---

Hospital Infection Control Measures in Cath Lab

• Strict aseptic technique: Sterile gowns, gloves, drapes
• Skin preparation with chlorhexidine at access site
• Antibiotic prophylaxis for implantable devices (pacemakers, device closures)
• Hand hygiene before and after every patient
• Daily cleaning of cath table and equipment with disinfectant

---

Conclusion

---

3. Left Ventriculography - Technique, Catheters, Views and Measurements

Introduction

---

Indications

1. Assessment of LV ejection fraction (EF)
2. Detection of regional wall motion abnormalities (RWMA) in IHD
3. Grading severity of mitral regurgitation
4. Detection of ventricular septal defect (VSD)
5. Diagnosis of hypertrophic obstructive cardiomyopathy (HOCM) - dynamic obstruction
6. Assessment of LV aneurysm or pseudo-aneurysm
7. Detection of LV thrombus

---

Contraindications

1. Severe aortic stenosis (difficulty crossing valve; risk of acute decompensation)
2. Recent myocardial infarction with hemodynamic instability
3. Elevated LVEDP >25 mmHg (adding contrast volume worsens pulmonary edema)
4. Severe LV dysfunction with very low EF
5. Contrast allergy

---

Catheters Used

• Has a curl at the end (pigtail shape) to prevent jet injury to endocardium
• Multiple side holes (8-12) for rapid, uniform contrast distribution
• Prevents contact of high-pressure jet with myocardium
• Size: 5F or 6F; inserted retrogradely across aortic valve

• End-hole closed; multiple side holes
• Used when pigtail cannot be advanced across aortic valve

• Balloon-tipped; inflated in LV to prevent jet injury
• Used in children

---

Technique

1. Pigtail catheter advanced retrogradely through aortic valve into LV using J-tip guidewire
2. Position confirmed: LV pressure waveform displayed; systolic >100 mmHg, LVEDP recorded
3. Catheter positioned in mid-cavity of LV (not in outflow tract or near mitral valve)
4. Power injector set: Volume 30-40 mL, flow rate 10-15 mL/sec, max pressure 600-900 psi
5. Contrast injected; simultaneous cine recording at 30 frames/sec
6. Patient may feel warm sensation during injection
7. After LVG, pullback from LV to Ao to record aortic valve gradient (if needed)

---

Angiographic Views

• Best view for LV function
• Shows: Anterior wall, inferior wall, apex, mitral valve
• Mitral regurgitation: Contrast seen entering left atrium (behind and above LV)
• Wall motion: Anterior (upper border) and inferior (lower border) assessed
• Most commonly used; recorded routinely

• Shows interventricular septum en face
• Septal wall motion and lateral wall motion assessed
• VSD: Contrast seen shunting across to right ventricle
• Used when anterior/inferior RWMA analysis is not sufficient from RAO alone

---

LV Function Assessment

• EF = (EDV - ESV) / EDV × 100%
• EDV = End-diastolic volume (largest frame - at QRS)
• ESV = End-systolic volume (smallest frame - at end of T wave)
• Area-length method used on RAO view to calculate volumes
• Normal EF: ≥55%
• Mild dysfunction: 45-54%
• Moderate dysfunction: 30-44%
• Severe dysfunction: <30%

---

Mitral Regurgitation Grading (Sellers Classification):

• Grade 1+: Faint contrast entering LA; clears with each beat
• Grade 2+: Mild opacification of LA; clears
• Grade 3+: Dense LA opacification = LV density; does not clear
• Grade 4+: Very dense LA opacification; contrast enters pulmonary veins

---

Complications of LVG

1. Ventricular ectopics / VT from catheter stimulation
2. Staining of myocardium if contrast injected in myocardium by mistake
3. Hypotension from contrast volume or LV decompensation
4. Embolism from air or clot
5. Mitral regurgitation worsening from catheter entrapment in chordae

---

Conclusion

---

3 MARK ANSWERS (Half Page Each)

---

1. Artery punctured with hollow needle at 45°
2. Soft-tipped guidewire threaded through needle into vessel
3. Needle removed over wire; wire stays in vessel
4. Dilator followed by sheath passed over wire using rotational movement
5. Wire and dilator removed; sheath remains; catheter introduced through sheath Eliminates surgical cutdown; allows repeated catheter exchanges safely.

---

1. Both radial and ulnar arteries at wrist compressed with thumbs
2. Patient makes tight fist until hand blanches (white)
3. Fist opened; radial artery pressure released while ulnar still compressed
4. If hand flushes pink within 5-10 seconds = Positive Allen test = Safe to use radial artery
5. If hand remains pale >10 sec = Negative = Radial artery access contraindicated

---

• TIMI 0: No flow; complete occlusion; no contrast beyond obstruction
• TIMI 1: Minimal flow; contrast enters but fails to opacify distal vessel
• TIMI 2: Partial flow; contrast fills entire vessel but more slowly than normal
• TIMI 3: Normal flow; brisk filling and washout of entire coronary artery

---

• Risk factors: Pre-existing renal disease, diabetes, dehydration, large contrast volume
• Prevention: IV hydration with normal saline 0.9% before and 6 hours after; use iso-osmolar contrast (Iodixanol); minimize contrast volume; avoid NSAIDs

---

1. Contrast syringe
2. Pressure transducer (for waveform monitoring)
3. Saline flush line
4. Waste/aspiration port The operator rotates stopcocks to switch between functions without disconnecting the catheter, preventing air entry and clot formation.

---

• Normal: 6-12 mmHg

• 18 mmHg: LV failure; pulmonary venous hypertension; risk of pulmonary edema

• Used to guide fluid therapy in ICU and distinguish cardiac from non-cardiac (ARDS) pulmonary edema

---

1. Ablation catheter placed at site of arrhythmia (mapped by EP study)
2. Radiofrequency current (300-500 kHz) delivered through catheter tip
3. Resistive heating raises tissue temperature to 50-60°C
4. Controlled coagulation necrosis destroys the arrhythmia pathway
5. Used for: SVT, WPW syndrome, atrial flutter, atrial fibrillation, ventricular tachycardia

---

1. Acts as a port through which multiple catheters can be exchanged without repeated arterial puncture
2. Hemostatic valve prevents blood backflow
3. Side port for flushing and drug/heparin administration
4. Sizes: 4F to 8F (French); length 10-25 cm
5. Removed at end of procedure; hemostasis achieved by manual compression or closure device

---

• Normal CO: Smooth curve; rapid temperature fall; gradual return to baseline
• Low CO: Slow fall in temperature; prolonged, large area under curve
• High CO: Rapid fall and rapid return; small area under curve
• Cardiac output is inversely proportional to area under the thermodilution curve

---

• Normal: 2.4-4.0 L/min/m²
• CI < 2.2: Heart failure
• CI < 1.8: Cardiogenic shock (Forrester class IV - requires inotropes or IABP)
• Calculated using BSA from DuBois formula: BSA = 0.007184 × Height^0.725 × Weight^0.425

---

• 10 mark → 9-10 marks வரும்
• 5 mark → 4-5 marks வரும்
• 3 mark → 3/3 marks வரும்

---

உண்மையான நிலைமை இது:

✅ ஒரே topic - மூணு section-லயும் வரலாம்!

---

📌 Exam-ல் எப்படி கேட்பாங்க என்று புரிஞ்சுக்கோ:

"Describe Coronary Angiography in detail"

"Write short note on Angiographic views in Coronary Angiography" "Write short note on Complications of Coronary Angiography"

"What is TIMI flow grade?" "Name the catheters used in Coronary Angiography" "What is Allen test?"

---

🎯 So நீங்க என்ன பண்ணணும்?

TOPIC: Cardiac Output

3 mark level  → Definition + Formula + Normal value மட்டும் தெரிஞ்சா போதும்
5 mark level  → Thermodilution method OR Fick principle - ஒண்ணு விவரமா
10 mark level → எல்லா methods + Shunt calculation + Clinical significance

---

📋 Most Important Topics - எல்லா level-லயும் வரக்கூடியவை:

---

💡 Simple Rule:

Top 3 topics (Coronary Angio, Cardiac Output, Pressure Recording) - இதை FULL-ஆ படி → எல்லா section-லயும் வரும்

Baaki topics (Radiation, Sterilization, LVG) - 5 mark + 3 mark level மட்டும் படி

Seldinger, Allen test, TIMI, Manifold - இதை 3 mark level மட்டும் படி

---

---

• 10 mark = 500 words के आसपास
• 5 mark = 300 words के आसपास
• 3 mark = 100 words के आसपास

"The topics you gave for 5 mark and 3 mark answers - are those topics ONLY asked for 5 mark and 3 mark in the actual exam? They won't come as 10 mark questions?"

---

Yes! That's correct!

---

So your exam preparation is simple:

1. Coronary Angiography
2. Cardiac Output determination
3. Pressure recording in cath lab

1. Radiation Protection
2. Sterilization Methods
3. Left Ventriculography
4. EP Study / RFA
5. PCWP
6. Swan-Ganz catheter
7. Catheters in cath lab
8. Shunt detection

1. Seldinger technique
2. Allen test
3. TIMI grades
4. Manifold
5. Contrast nephropathy
6. Cardiac Index
7. Thermodilution curve
8. Sheath
9. Pullback gradient
10. Fick formula

---

---

3rd Year Paper I Syllabus vs What We Covered

---

✅ COVERED Topics:

---

❌ MISSING Topics - Need to cover these:

5 Mark level:

1. Preparing cath lab for diagnostic study (lab setup checklist)
2. Lab preparation for coronary angiography
3. Right heart catheterization
4. Equipment used in arrhythmia induction and mapping
5. Ventricular assist device (VAD)
6. Fundamentals of pacemaker

3 Mark level:

1. Principles of oximetry
2. ECM (External Cardiac Massage / CPR basics)
3. Table and image intensifier movements (detailed)

---

Shall I write answers for these missing topics now?

Missing Topics - Complete Answers

---

5 MARK ANSWERS (2-3 Pages)

---

1. Right Heart Catheterization - Technique, Pressures and Indications

Introduction

---

Indications

1. Diagnosis and severity assessment of pulmonary arterial hypertension
2. Assessment of heart failure - differentiate cardiac vs. non-cardiac cause
3. Evaluation of valvular heart disease (mitral stenosis, tricuspid disease)
4. Diagnosis of constrictive pericarditis vs. restrictive cardiomyopathy
5. Measurement of cardiac output (thermodilution)
6. Assessment of intracardiac shunts (ASD, VSD, PDA) - oxygen saturation run
7. Guiding therapy in cardiogenic shock and post-cardiac surgery ICU

---

Catheter Used - Swan-Ganz Catheter (Balloon-tipped Pulmonary Artery Catheter)

• 7F, 110 cm long; 4 lumens
• Proximal lumen (RA port): At 30 cm from tip; CVP monitoring; thermodilution injectate
• Distal lumen (PA port): At tip; PA pressure + PCWP
• Balloon port: Inflates 1.5 mL air balloon at tip
• Thermistor: 4 cm from tip; measures temperature for thermodilution CO

---

Venous Access

• Right internal jugular vein (most common - straight path to RA)
• Subclavian vein
• Femoral vein
• Antecubital vein (less common)

---

Technique - Step by Step

1. Venous access obtained using Seldinger technique; 7F sheath inserted
2. Swan-Ganz catheter introduced through sheath
3. Balloon inflated with 1.5 mL air when catheter enters the vein
4. Catheter "floats" with blood flow; position confirmed by pressure waveforms:
   • RA: Low, flat waveform (mean 0-8 mmHg)
   • RV: High systolic, low diastolic (15-30/0-8 mmHg) - "square root sign"
   • PA: High systolic, higher diastolic than RV (15-30/8-15 mmHg) - dicrotic notch appears
   • PCWP: Low, atrial-like waveform (mean 6-12 mmHg) - balloon wedged
5. Balloon deflated after PCWP recording; catheter remains in PA
6. All pressures recorded; blood samples drawn for oxygen saturation run
7. Cardiac output measured by thermodilution

---

Pressure Waveforms During Flotation

---

Complications

1. Pneumothorax (subclavian/jugular access)
2. Pulmonary artery rupture (over-wedging with balloon inflated too long)
3. Arrhythmias (catheter tip in RV - PVCs, VT)
4. Pulmonary infarction (catheter migrates distally and wedges permanently)
5. Catheter knotting in RV
6. Infection - catheter-related bloodstream infection

---

Clinical Applications of RHC Data

• Pulmonary hypertension: mPAP >25 mmHg; PVR calculated
• Mitral stenosis: Elevated PCWP; transmitral gradient
• Cardiac tamponade: Equalization of RA, RV diastolic, PA diastolic, PCWP
• Constrictive pericarditis: Equalization + dip-and-plateau pattern in RV
• Cardiogenic shock: Low CO, high PCWP, high SVR

---

Conclusion

---

2. Fundamentals of Pacemaker

Introduction

---

Indications for Pacing

1. Complete heart block (3rd degree AV block)
2. Symptomatic sinus bradycardia not responding to medication
3. Sick sinus syndrome
4. 2nd degree AV block (Mobitz type II)
5. Bifascicular and trifascicular block with symptoms
6. Neurocardiogenic syncope (vasovagal)
7. Hypertrophic obstructive cardiomyopathy (HOCM) - dual chamber pacing

---

Types of Pacemakers

• Used in emergencies (acute heart block, post-cardiac surgery)
• Transvenous: Lead placed via femoral/subclavian vein into RV
• External (transcutaneous): Pacing pads on chest wall; painful; emergency only
• Generator external; connected to bedside pacemaker box

• Implanted subcutaneously below left or right clavicle
• Generator (battery) placed in subcutaneous pocket
• Lead(s) tunneled through subclavian/cephalic vein to heart

---

Types of Permanent Pacemakers

---

Pacemaker Code (NBG Code - 5 letters)

---

Pacemaker Parameters

• Rate: Usually set 60 ppm (beats per minute) as lower rate limit
• Output (mA): Energy delivered; usually 2-3x threshold
• Sensitivity (mV): How well pacemaker detects native beats
• AV delay (in DDD): Time between atrial and ventricular pacing (usually 150-200 ms)

---

Setting Up Lab for Permanent Pacing

1. Sterile operative field; lead apron for radiation protection
2. Fluoroscopy C-arm positioned for AP and LAO views
3. Pacing system analyser (PSA) connected to measure thresholds
4. Temporary pacing backup ready
5. Defibrillator on standby
6. Instruments: Pacemaker generator, leads (active/passive fixation), introducer set, pocket tools

---

Pacemaker Follow-up

• Check at 1 month, 3 months, then every 6 months
• Parameters checked: Sensing, pacing threshold, impedance, battery status
• Battery life: 7-12 years depending on usage

---

Conclusion

---

3. Ventricular Assist Device (VAD)

Introduction

---

Indications

1. Cardiogenic shock after myocardial infarction
2. Bridge to transplant (BTT) - keeping patient alive until heart transplant
3. Bridge to recovery (BTR) - myocarditis, post-cardiotomy shock
4. Destination therapy (DT) - permanent use in patients not eligible for transplant
5. Bridge to decision - while assessing transplant eligibility

---

Types of VAD

• Draws blood from LV apex → pumps to ascending aorta
• Bypasses the failing left ventricle
• Used in left heart failure

• Draws blood from RA → pumps to pulmonary artery
• Used in right heart failure

• Both LVAD + RVAD together
• Used in total cardiac failure

---

Types by Mechanism

---

IABP (Intra-Aortic Balloon Pump) - Simplest VAD

• Balloon catheter inserted via femoral artery; tip in descending aorta
• Counterpulsation principle:
  • Balloon inflates during diastole → increases coronary perfusion pressure
  • Balloon deflates just before systole → reduces afterload; LV ejects more easily
• Timing: Triggered by ECG (R wave) or arterial pressure waveform
• Indications: Cardiogenic shock, pre-PTCA in high-risk patients, post-cardiac surgery low output
• Contraindications: Aortic regurgitation, aortic dissection, severe peripheral vascular disease

---

Complications of VAD

1. Bleeding (anticoagulation needed)
2. Stroke (thromboembolism)
3. Device infection
4. Device malfunction/pump failure
5. Right heart failure (after LVAD - increased preload to RV)
6. Hemolysis (red cell destruction by pump)

---

Conclusion

---

4. Preparing the Cath Lab for a Diagnostic Study / Lab Setup

Introduction

---

Pre-procedure Lab Checklist

• X-ray system (fluoroscopy + cine): Tested and functioning
• Image intensifier (II) / flat panel detector: Calibrated
• Table: Functional movements (longitudinal, lateral, height, tilt)
• Hemodynamic monitoring system: Transducers connected, zeroed, calibrated
• Power injector: Loaded with contrast, pressure tested
• Defibrillator: Charged, pads connected, tested
• Emergency cart (crash cart): Fully stocked - drugs, airway equipment

• Sterile drapes placed on procedure table
• Sterile gown and gloves for operator
• Sterile field prepared with:
  • Catheter tray (catheters, guidewires, sheaths)
  • Manifold assembled and de-aired
  • Contrast syringes filled
  • Heparinized saline flush bowls
  • Needles, scalpel, sutures

• Non-ionic contrast (Iohexol/Omnipaque) drawn into labeled syringes
• Contrast warmed to body temperature (reduces viscosity and patient discomfort)
• Contrast volume documented

• Transducers connected to monitoring system
• Zero reference set at phlebostatic axis (mid-chest level)
• Calibration verified against known pressure
• All channels labeled (RA, RV, PA, Ao, LV)

• Lead aprons worn by all staff
• Thyroid collars and lead glasses available
• Ceiling-mounted shield positioned
• Dosimeters worn by all personnel
• Image intensifier positioned correctly

• Patient transferred to cath table; identity verified
• ECG leads connected; continuous monitoring started
• Blood pressure cuff on arm; pulse oximeter attached
• Groin or wrist prepped and draped
• IV line patency checked
• Sedation given if prescribed

• Patient details entered into cath lab computer (DICOM system)
• Study type selected (diagnostic / PTCA / EP study)
• Radiation dose tracking started

---

Post-procedure Lab Cleanup

1. Used catheters and sharps disposed in sharps container
2. Table cleaned with disinfectant
3. Reusable equipment sent for sterilization
4. Contrast syringes and tubing discarded
5. Radiation dose recorded in log
6. Images archived to PACS (Picture Archiving System)

---

Conclusion

---

5. Equipment Used in Arrhythmia Induction and Mapping (EP Study)

Introduction

---

Equipment List

• Records electrical signals (electrograms) from multiple intracardiac catheters simultaneously
• Displays local electrograms alongside surface ECG leads
• Measures conduction intervals (PA, AH, HV intervals)
• Examples: GE CardioLab, Bard LabSystem Pro, Prucka CardioLab

• Delivers precisely timed electrical stimuli to heart through EP catheters
• Used for:
  • Programmed Electrical Stimulation (PES): S1-S2-S3 extra stimuli to induce tachycardia
  • Burst pacing: Rapid pacing to initiate atrial flutter/AF/VT
  • Overdrive suppression: Pacing faster than tachycardia to terminate it
• Parameters set: Cycle length, number of stimuli, output (mA), coupling intervals

• Delivers RF current (300-500 kHz) to ablation catheter tip
• Heats tissue to 50-60°C for controlled ablation
• Monitors tip temperature, impedance, and power in real-time
• Safety cutoff if temperature exceeds limit or impedance rises suddenly (steam pop)
• Examples: Biosense Webster Stockert generator, Medtronic RF generator

• Creates a 3-dimensional map of the heart chamber
• Catheter tip position tracked by magnetic or electrical field
• Two types:
  • CARTO (Biosense Webster): Magnetic field-based mapping
  • EnSite NavX / Precision (Abbott): Electrical field-based mapping
• Color-coded map shows:
  • Voltage map (scar vs. normal tissue)
  • Activation map (timing of electrical activation)
  • Propagation map (direction of wavefront)

• Ultrasound catheter placed inside heart (usually RA)
• Real-time visualization of cardiac structures during EP procedure
• Used for transseptal puncture guidance, catheter positioning, monitoring for complications

• Confirms catheter positions in AP, LAO, RAO views
• Used alongside mapping systems

---

Conclusion

---

3 MARK ANSWERS (Half Page)

---

1. Principles of Oximetry

• Oxygenated hemoglobin (HbO₂) and deoxygenated hemoglobin (Hb) absorb light at different wavelengths
• HbO₂ absorbs more infrared light (940 nm)
• Hb (deoxygenated) absorbs more red light (660 nm)
• Ratio of red to infrared absorption calculated → gives SpO₂ %

1. Pulse oximeter: Non-invasive; probe on finger/ear; measures SpO₂ continuously
2. Co-oximeter (lab): Measures actual SaO₂ from arterial blood sample

• Oxygen saturation measured from blood samples at different cardiac chambers
• Step-up in saturation identifies level of intracardiac shunt (ASD/VSD/PDA)
• Normal saturations: SVC 70%, RA 75%, RV 75%, PA 75%, Aorta 98%

---

2. ECM - External Cardiac Massage (CPR Basics)

1. Patient flat on hard surface; call for help
2. Heel of hand placed on lower half of sternum
3. Compress chest 5-6 cm depth at rate of 100-120 per minute
4. Allow full chest recoil between compressions
5. Ratio: 30 compressions : 2 rescue breaths (30:2)

• Cardiac arrest can occur due to arrhythmia, contrast reaction, or perforation
• Cath table lowered flat immediately
• CPR started; defibrillator charged
• ACLS protocol followed
• Adrenaline 1 mg IV every 3-5 minutes

---

3. Table and Image Intensifier Movements

1. Longitudinal (cranial-caudal): Moves patient head-to-foot; used to position area of interest under X-ray beam
2. Lateral (left-right): Side-to-side movement for centering
3. Height: Raises/lowers table to optimize geometry
4. Tilt: Trendelenburg (head down) in hypotension; reverse Trendelenburg (head up) if needed

1. RAO (Right Anterior Oblique): C-arm rotates to patient's right side
2. LAO (Left Anterior Oblique): C-arm rotates to patient's left side
3. Cranial: II tilts toward patient's head; opens up inferior structures
4. Caudal: II tilts toward patient's feet; opens up superior structures
5. AP (Anterior-Posterior): Straight frontal view; zero angulation

---

COMPLETE TOPIC COVERAGE SUMMARY

✅ NOW ALL TOPICS COVERED:

10 Mark (Essays - 3 questions):

1. ✅ Coronary Angiography
2. ✅ Cardiac Output (Thermodilution + Fick)
3. ✅ Pressure Recording + Waveforms + Gradients

5 Mark (Short Notes - 8 questions):

1. ✅ Radiation Protection
2. ✅ Sterilization Methods
3. ✅ Left Ventriculography
4. ✅ Right Heart Catheterization
5. ✅ Fundamentals of Pacemaker
6. ✅ Ventricular Assist Device / IABP
7. ✅ Cath Lab Setup / Lab Preparation
8. ✅ EP Study Equipment + RFA

3 Mark (Short Answers - 10 questions):

1. ✅ Seldinger Technique
2. ✅ Allen Test
3. ✅ TIMI Grades
4. ✅ Manifold
5. ✅ Contrast Nephropathy
6. ✅ Cardiac Index
7. ✅ Thermodilution Curve
8. ✅ Principles of Oximetry
9. ✅ ECM / CPR
10. ✅ Table and II Movements

---

---

3rd Year Paper II - Cardiac Catheterization Laboratory Advanced

Complete Exam-Ready Answers

---

10 MARK ANSWERS (Essays - 3-4 Pages)

---

ESSAY 1: Coronary Angioplasty (PTCA) - Equipment, Technique, Setup and Complications

Introduction

---

Indications

1. Stable angina with significant stenosis (≥70%) not responding to medical therapy
2. Unstable angina / NSTEMI
3. STEMI - primary PCI (most important indication; opens blocked artery within 90 min)
4. Post-thrombolysis residual stenosis
5. Multi-vessel disease (staged PCI)
6. In-stent restenosis

---

Contraindications

1. Left main disease with no surgical backup
2. Diffuse multi-vessel disease better suited for CABG
3. Severe contrast allergy
4. Severe renal failure
5. Non-significant stenosis (<50%)
6. Patient unable to take dual antiplatelet therapy

---

Equipment and Hardware Used in PTCA

• Larger, stiffer catheter than diagnostic catheter
• Provides coaxial alignment with coronary ostium and back-up support for devices
• Size: 6F, 7F, or 8F
• Types: JL 3.5/4.0, JR 4.0, EBU, XB, Amplatz, Hockey stick
• Has large inner lumen to pass guidewire + balloon/stent simultaneously
• Connected to manifold for pressure monitoring + contrast injection

• Ultra-thin wire (0.014 inch = 0.36 mm diameter) passed through guiding catheter
• Crosses the stenosis first; acts as a rail for balloon and stent
• Parts: Proximal shaft (stiff) + distal tip (soft, flexible, steerable)
• Types:
  • Workhorse wire: BMW, Runthrough, Whisper (routine stenosis)
  • Hydrophilic wire: Pilot 150, Fielder (for tortuous vessels)
  • CTO wire: Miracle, Confianza Pro (for total occlusions - very stiff)
• Length: 180-300 cm

• Passed over guidewire to site of stenosis
• Inflated with diluted contrast using indeflator device
• Inflation pressure: 6-20 atm; duration 20-30 seconds
• Balloon sizes: 2.0 mm to 4.5 mm diameter; 10-20 mm length
• Types:
  • Semi-compliant: For pre-dilation; expands beyond nominal size at high pressure
  • Non-compliant: For post-dilation/stent expansion; holds exact size at high pressure
  • Cutting balloon: Has small blades on surface; for resistant/calcified lesions
  • Scoring balloon: AngioSculpt; for calcified, resistant lesions

• Metal mesh scaffold deployed inside artery after balloon dilation
• Prevents elastic recoil and arterial dissection (two main problems of plain balloon PTCA)
• Sizes: 2.25-5.0 mm diameter; 8-38 mm length
• Types:

---

Setting Up the Cath Lab for a PTCA Case

1. Diagnostic angiogram reviewed; target lesion identified
2. Appropriate guiding catheter, guidewire, balloon, stent selected and loaded
3. Antiplatelet preloading: Aspirin 325 mg + Clopidogrel 600 mg (or Ticagrelor 180 mg) given
4. Heparin 70-100 units/kg IV given after guiding catheter engaged; ACT (Activated Clotting Time) checked (target 250-350 sec)
5. Power injector loaded with contrast
6. IABP on standby for high-risk cases
7. Defibrillator charged and ready
8. Perfusionist and cardiac surgeon notified for high-risk cases

1. Guiding catheter engaged in coronary ostium; pressure damping checked
2. Guidewire advanced through stenosis into distal vessel under fluoroscopy
3. Balloon pre-dilation if stent cannot cross or lesion is calcified
4. Stent (mounted on balloon) advanced over wire to lesion site
5. Stent positioned using fluoroscopic landmarks + road map
6. Balloon inflated; stent deployed at 8-16 atm; balloon deflated and removed
7. Post-dilation with non-compliant balloon at high pressure (16-20 atm) for optimal stent expansion
8. Final angiogram taken in multiple views to assess result
9. TIMI 3 flow with <20% residual stenosis = successful result

---

Management of Complications

• Cause: Microvascular spasm, embolization of plaque debris, air embolism
• Treatment:
  • Intracoronary adenosine (100-200 mcg) or nitroprusside
  • Intracoronary verapamil
  • GP IIb/IIIa inhibitor (abciximab/tirofiban) if thrombotic
  • IABP if hemodynamically unstable

• Occurs within 24 hours of stent deployment
• Cause: Inadequate stent expansion, missed dissection, premature stoppage of DAPT
• Presentation: Acute MI; sudden ST elevation
• Treatment: Urgent repeat angiography + balloon inflation / new stent; GP IIb/IIIa inhibitor; aspiration thrombectomy

• Intimal tear during balloon inflation or guidewire passage
• Types A-F (NHLBI classification); Type C-F are serious
• Treatment: Cover with stent; prolonged balloon inflation

• Full-thickness tear of coronary wall; rare but life-threatening
• Cause: Hydrophilic wire, oversized balloon, atherectomy
• Signs: Contrast extravasation; hemopericardium; tamponade
• Treatment: Prolonged balloon inflation to seal; covered stent; pericardiocentesis for tamponade; emergency surgery

• Side branch trapped under stent struts
• Treatment: Guidewire into side branch + balloon dilation (kissing balloon technique)

---

Post-procedure Care

• Dual antiplatelet therapy (DAPT): Aspirin lifelong + Clopidogrel/Ticagrelor for 1-12 months
• Sheath removal after ACT <180 sec; hemostasis by manual compression or closure device
• Monitor ECG, BP, access site for 4-6 hours post-procedure

---

Conclusion

---

ESSAY 2: Balloon Mitral Valvuloplasty (BMV) - Technique, Hardware, Transseptal Puncture and Complications

Introduction

---

Indications (Wilkins Score ≤8)

1. Symptomatic mitral stenosis (MVA <1.5 cm²) with suitable valve morphology
2. Wilkins score ≤8 (low score = good result): Assesses leaflet mobility, thickening, calcification, subvalvular apparatus
3. No left atrial thrombus on TEE
4. No significant mitral regurgitation (MR ≤ grade 2)
5. Asymptomatic severe MS with pulmonary hypertension

---

Contraindications

1. LA thrombus on TEE (absolute)
2. Significant MR (≥ grade 3)
3. Severe calcification (Wilkins score >12)
4. Severe subvalvular disease
5. Concomitant severe aortic valve disease requiring surgery

---

Hardware and Equipment Used in BMV

• Self-positioning, pressure-extensible latex balloon
• Unique design: Distal part inflates first (anchors in LV), then proximal, then middle (splits commissures)
• Available sizes: 24, 26, 28, 30 mm
• Size selection: Height (cm) / 10 + 10 = balloon size in mm
• Example: Height 160 cm → 160/10 + 10 = 26 mm balloon

• Two separate balloons inflated simultaneously across mitral valve
• Less used now; more complex; higher complication rate

• Brockenbrough needle (curved, hollow)
• Mullins transseptal sheath + dilator
• Used to cross from RA to LA through the interatrial septum

• 0.025 inch coiled guidewire (for Inoue balloon)
• Pressure monitoring setup (LA, LV simultaneous pressures)
• TEE probe (for real-time guidance)
• Fluoroscopy C-arm

---

Transseptal Puncture - Technique

1. Mullins sheath + dilator advanced from femoral vein to SVC
2. Brockenbrough needle loaded inside sheath
3. Assembly pulled down from SVC; "jump" from aortic knuckle to fossa ovalis felt
4. Needle direction confirmed: AP view (needle pointing posteriorly at 4-5 o'clock), LAO view (pointing posteriorly)
5. TEE confirms needle tip at fossa ovalis (tenting of septum seen)
6. Needle advanced to puncture fossa ovalis into LA
7. LA position confirmed by:
   • LA pressure waveform (mean 10-15 mmHg with a and v waves)
   • Contrast injection shows free flow in LA
   • Oxygen saturation from LA blood higher than RA
8. Sheath and dilator advanced over needle into LA; needle removed

• Cardiac tamponade (perforation of free wall or aortic root)
• Aortic puncture
• Air embolism

---

BMV Procedure - Step by Step

1. Baseline hemodynamics: LA pressure, LV pressure, transmitral gradient recorded
2. Mitral valve area calculated by Gorlin formula or pressure half-time method
3. Inoue balloon loaded on delivery system; introduced via femoral vein → IVC → RA → LA (via transseptal puncture)
4. Coiled guidewire advanced into LV via mitral valve
5. Balloon tracked over wire, positioned across mitral valve
6. Balloon inflated in stepwise fashion:
   • Distal balloon inflated first → anchors in LV
   • Full inflation → balloon waist at mitral valve; inflated to split commissures
   • Immediate deflation
7. Hemodynamics reassessed: Transmitral gradient should decrease; LA pressure should fall
8. Repeat balloon inflations with increasing balloon size until optimal result
9. Final assessment: Transmitral gradient <5 mmHg; MVA >1.5 cm²

---

Recording of Transmitral Pressure Gradients

• LA pressure recorded via transseptal catheter
• LV pressure recorded via separate arterial catheter (retrograde across aortic valve) or by simultaneous LA-LV recording
• Transmitral gradient = Mean LA pressure - Mean LV diastolic pressure
• Pre-BMV: Usually 10-20 mmHg
• Post-BMV: Should be <5 mmHg for good result
• Mitral valve area calculated: Gorlin formula: MVA = CO / (37.7 × √mean gradient)

---

Management of Cardiac Tamponade

• Sudden hypotension + tachycardia
• Equalization of RA, RV, PA diastolic, and PCWP pressures
• Fluoroscopy: Enlarged cardiac silhouette; absent cardiac pulsation
• Echo: Pericardial effusion + RV collapse

1. Stop procedure immediately
2. Call for help; prepare for emergency pericardiocentesis
3. Pericardiocentesis: Needle inserted subxiphoid approach; fluid aspirated
4. Pigtail catheter left in pericardium for continued drainage
5. Protamine to reverse heparin (if procedure was anticoagulated)
6. If bleeding continues → emergency cardiac surgery

---

Complications of BMV

---

Conclusion

---

ESSAY 3: Aortic Angiography, Peripheral Angiography and Thromboembolic Disease

Introduction

---

AORTIC ANGIOGRAPHY

1. Aortic regurgitation - severity assessment
2. Aortic dissection - Type A or B
3. Aortic aneurysm - extent and involvement of branches
4. Coarctation of aorta
5. Takayasu arteritis
6. Pre-TAVI assessment (aortic root angiography)

• Grade 1+: Faint contrast in LV; clears quickly
• Grade 2+: Mild LV opacification; clears
• Grade 3+: LV opacification = Aorta density; does not clear
• Grade 4+: Dense LV opacification; entire LV fills on first beat

---

PERIPHERAL ANGIOGRAPHY

1. Peripheral arterial disease (claudication, rest pain, gangrene)
2. Renal artery stenosis (hypertension assessment)
3. Carotid artery stenosis
4. Pre-amputation limb assessment
5. Mesenteric ischemia
6. Iliac artery disease

• CO₂ gas used as contrast agent instead of iodinated contrast
• Used when iodinated contrast is contraindicated (severe renal failure, contrast allergy)
• CO₂ is non-nephrotoxic, non-allergenic
• Absorbed by body within minutes
• Disadvantage: Image quality inferior; cannot use for coronary or cerebral angiography (risk of gas embolism)
• Equipment: CO₂ delivery system with pressure regulator

---

PERIPHERAL INTERVENTIONS

1. Long sheaths (45-90 cm) for access to peripheral vessels
2. Peripheral guidewires (0.035 inch, 0.018 inch)
3. Peripheral balloons (PTA balloons): Larger diameter (4-10 mm), longer length (40-200 mm)
4. Self-expanding stents: Nitinol stents (flexible, conform to vessel movement); used in iliac, femoral, carotid arteries
5. Covered stents (stent grafts): PTFE-covered; used for aneurysm exclusion
6. Cutting balloons: For resistant lesions
7. Atherectomy devices: Orbital, directional, laser (for calcified/resistant lesions)

• Endovascular Aortic Repair: Stent graft deployed inside aortic aneurysm via femoral artery
• Excludes aneurysm sac from circulation; prevents rupture
• Less invasive than open surgical repair
• Graft anchored above and below aneurysm in normal aortic segments

---

THROMBOEMBOLIC DISEASE

• Indications: Deep vein thrombosis (DVT) or pulmonary embolism with contraindication to anticoagulation; recurrent PE despite anticoagulation
• Filter inserted via femoral or jugular vein; deployed in infrarenal IVC
• Traps thrombus from lower limb DVT before it reaches lungs
• Types: Permanent (Greenfield) or Retrievable (optional, can be removed later)

• Catheter-directed thrombolysis (CDT): Thrombolytic drug infused directly through catheter into clot
• Drugs used: Alteplase (tPA), Urokinase, Streptokinase
• Advantage over systemic thrombolysis: Lower drug dose; less bleeding risk
• Used for: Massive PE, iliofemoral DVT, peripheral arterial occlusion

• Coronary: Export catheter, Pronto catheter (manual aspiration of thrombus in STEMI)
• Peripheral: Angiojet (rheolytic thrombectomy - high-pressure saline jet breaks up clot; aspirated simultaneously)
• Indications: Large thrombus burden in coronary (STEMI), peripheral arterial occlusion

---

Contrast Agents - Summary

1. IV normal saline 0.9% - 1 mL/kg/hr for 12 hours before and after
2. Minimum contrast volume (keep <3 mL/kg or 300 mL total)
3. Iso-osmolar contrast (Iodixanol) preferred in high-risk patients
4. Avoid NSAIDs and nephrotoxic drugs for 48 hours
5. N-acetylcysteine 600 mg BD on day before and day of procedure
6. Avoid repeat contrast within 48-72 hours

---

Conclusion

---

5 MARK ANSWERS (2-3 Pages)

---

1. Pediatric Interventions - Device Closure of PDA, ASD, VSD

Introduction

---

1. Device Closure of PDA (Patent Ductus Arteriosus)

• Amplatzer Duct Occluder (ADO): Mushroom-shaped nitinol mesh; most commonly used
• Coil closure (Gianturco coil): For small PDAs; simple; less expensive
• Amplatzer Vascular Plug: For tubular PDAs

1. Right heart catheterization via femoral vein
2. Catheter advanced PA → PDA → aorta
3. Angiogram in lateral view to define PDA shape and size
4. Device selected (PDA diameter + 2 mm)
5. Delivery sheath positioned in aorta
6. Device deployed: Aortic disc opens in aorta; waist in PDA; PA disc in PA
7. Confirmed by angiogram; released if position satisfactory
8. No residual shunt = success

---

2. Device Closure of ASD (Atrial Septal Defect)

1. TEE/ICE guidance mandatory for sizing and positioning
2. Sizing balloon passed through ASD; balloon inflated; stretched diameter measured
3. Device selected (same size as stretched diameter)
4. Long sheath advanced from RA → through ASD → into LA
5. Left atrial disc deployed in LA; pulled back to septum; right atrial disc deployed in RA
6. TEE confirms good position; no impingement on mitral valve or pulmonary veins
7. Device released; TEE shows no residual shunt

• Adequate rims (≥5 mm) around defect for device anchoring
• Defect size ≤38 mm
• No anomalous pulmonary venous drainage

---

3. Device Closure of VSD (Ventricular Septal Defect)

1. Arteriovenous loop created: Wire passed from RV through VSD to LV → aorta → femoral artery
2. Long sheath advanced via arteriovenous loop from femoral vein → RV → VSD → LV
3. LV disc deployed in LV; waist in VSD; RV disc in RV
4. Confirmed by angiogram; released

---

Coil Closure of PDA

• Gianturco coil: Stainless steel wire with Dacron fibers; coils when released
• For small PDAs (≤2.5 mm)
• Simple deployment through catheter
• Coil lodges in PDA; thrombosis occurs; complete occlusion in 24-48 hours

---

2. IABP (Intra-Aortic Balloon Pump) - Theory, Indications, Setup

Introduction

---

Theory of Counterpulsation

• Balloon placed in descending thoracic aorta via femoral artery
• Helium gas used to inflate/deflate (low density = fast movement; safe if leak)

• Balloon inflates at onset of diastole (at dicrotic notch)
• Displaces blood proximally and distally
• Increases diastolic aortic pressure → increased coronary perfusion pressure → better myocardial oxygen supply

• Balloon deflates just before LV systole (at end of diastole)
• Creates sudden vacuum in aorta
• Reduces afterload (resistance against which LV ejects) → LV workload reduced → less oxygen demand

• ↑ Coronary blood flow
• ↓ LV afterload
• ↓ Myocardial oxygen demand
• ↑ Cardiac output (by 10-20%)

---

Indications for IABP

1. Cardiogenic shock post-MI
2. Unstable angina refractory to medical therapy
3. High-risk PTCA (left main, severe LV dysfunction)
4. Mechanical complications of MI (acute MR, VSD)
5. Bridge to cardiac surgery or transplant
6. Post-cardiac surgery low output syndrome
7. Weaning from cardiopulmonary bypass

Contraindications

1. Aortic regurgitation (balloon inflation worsens AR)
2. Aortic dissection
3. Severe peripheral vascular disease
4. Abdominal aortic aneurysm

---

Setting Up the IABP System

1. 7.5F or 8F balloon catheter inserted via femoral artery (Seldinger technique)
2. Tip positioned just distal to left subclavian artery origin (2-3 cm below aortic arch) - confirmed by CXR
3. Catheter connected to IABP console
4. Console set to:
   • Trigger mode: ECG trigger (R wave) or arterial pressure trigger
   • Assist frequency: 1:1 (every beat); 1:2 (every 2nd beat for weaning)
   • Inflation timing: Set at dicrotic notch
   • Deflation timing: Set at end of diastole
5. Timing verified on arterial waveform:
   • Augmented diastolic pressure should be higher than unassisted systolic
   • Assisted systolic lower than unassisted systolic (afterload reduction confirmed)

---

3. Cardiac Pacing - Temporary and Permanent

Temporary Pacing

• Acute complete heart block (post-MI, post-cardiac surgery)
• Symptomatic bradycardia not responding to atropine
• Overdrive pacing for tachyarrhythmias
• Bridge until permanent pacemaker implanted

1. Femoral or subclavian vein access; 5F sheath inserted
2. Bipolar pacing lead advanced to RV apex under fluoroscopy
3. RV apex position confirmed: LAO view shows tip pointing anteriorly and leftward
4. Pacing threshold tested: Minimum voltage to consistently capture ventricle (should be <1V)
5. Lead connected to external temporary pacing generator
6. Rate set (usually 60 ppm); output set at 2-3x threshold; sensitivity set
7. 12-lead ECG shows LBBB pattern (confirms RV pacing)

---

Permanent Pacemaker Implantation

1. Left (or right) deltopectoral groove incision under local anesthesia
2. Cephalic vein cutdown or subclavian vein puncture for lead access
3. Lead(s) advanced under fluoroscopy:
   • RV lead: To RV apex (passive fixation - tines) or RV septum/RVOT (active fixation - screw)
   • RA lead: To RA appendage (J-shaped active or passive lead)
4. Pacing System Analyser (PSA) connected: Measures threshold, sensing, impedance
   • Good threshold: <1V at 0.5 ms pulse width
   • Good sensing: R wave >5 mV (ventricle), P wave >2 mV (atrium)
   • Impedance: 300-1000 Ω
5. Leads secured at vein entry; pocket created in subcutaneous tissue
6. Generator connected to leads; placed in pocket
7. Pocket closed; dressing applied
8. CXR to confirm lead positions + rule out pneumothorax

---

4. Image Archival Systems and CD Writing

Introduction

---

DICOM Format

• Digital Imaging and Communications in Medicine
• International standard format for all medical imaging
• All cath lab images stored as DICOM files
• Contains: Image data + patient information + acquisition parameters + metadata

---

PACS (Picture Archiving and Communication System)

• Central server storing all DICOM images from cath lab
• Images accessible from any workstation in hospital network
• Allows review, reporting, comparison with previous studies
• Backup: Images mirrored to secondary server for data safety

---

Cath Lab Recording System

• Hemodynamic data, pressure waveforms, ECG recorded simultaneously with cine images
• All synchronized with patient ID and study timestamp
• Typical storage: 1-2 GB per complete cath study

---

CD / DVD Writing

• Patient receives copy of their cath study on CD/DVD at discharge
• CD contains: DICOM images + viewer software
• Doctor can review on any PC using the included viewer
• Medico-legal record; used for second opinion, follow-up at different hospital

---

Modern Archival

• Cloud-based PACS: Images stored on cloud servers; accessible remotely
• USB drives replacing CDs in many centers
• DICOM CD writing station in cath lab writes study within 10-15 minutes

---

5. Aortic and Pulmonary Valvuloplasty

Balloon Aortic Valvuloplasty (BAV)

1. Arterial access; pigtail in LV; simultaneous Ao pressure recorded
2. Stiff guidewire placed in LV apex
3. Balloon (18-20 mm) advanced retrogradely across aortic valve
4. Balloon inflated during rapid ventricular pacing (200 bpm) - heart stopped briefly to prevent balloon ejection
5. Commissures and calcified leaflets cracked open
6. Post-procedure: Gradient reduced; but restenosis occurs in 6-12 months (palliative, not curative)

---

Balloon Pulmonary Valvuloplasty (BPV)

1. Venous access; right heart catheterization; RV-PA gradient measured
2. Stiff guidewire passed through pulmonary valve into distal PA
3. Balloon (balloon:annulus ratio 1.2:1) inflated across pulmonary valve
4. "Waist" seen at valve level during inflation; disappears when commissures split
5. Post-procedure: Gradient should decrease to <25 mmHg
6. Result: Usually excellent; curative in most cases; low recurrence

---

3 MARK ANSWERS (Half Page)

---

1. Catheter advanced from femoral artery to ascending aorta; angiogram shows narrowing
2. Gradient measured across coarctation (significant if >20 mmHg)
3. Guidewire crossed through narrowing
4. Balloon dilation first; then stent deployed (covered stent in adults)
5. Post-procedure: Gradient abolished; BP normalizes in upper limbs

---

---

• Drug: Everolimus, Sirolimus, Zotarolimus, Paclitaxel
• Mechanism: Drug inhibits smooth muscle cell proliferation that causes restenosis
• Advantage: Restenosis rate <5% (vs. BMS 20-30%)
• Disadvantage: Requires 12 months of dual antiplatelet therapy (DAPT) to prevent late stent thrombosis

---

1. Brockenbrough needle inside Mullins sheath advanced from femoral vein to SVC
2. Pulled down; tip positioned at fossa ovalis (confirmed by "jump" + TEE tenting)
3. Needle advanced to puncture fossa ovalis into LA
4. Confirmed by LA pressure waveform and contrast injection
5. Sheath advanced into LA over needle; needle removed

---

• Not balloon-expandable; expand due to thermal/elastic memory
• Used in: Peripheral arteries (iliac, femoral, carotid, renal)
• Advantage: Flexible; conforms to vessel curvature and movement; resistant to external compression
• Disadvantage: Cannot be precisely expanded like balloon stents; may foreshorten

---

• 4 parameters scored 0-4 each:
  1. Leaflet mobility
  2. Leaflet thickening
  3. Valve calcification
  4. Subvalvular apparatus thickening
• Total score ≤8 = Good candidate for BMV (favorable result expected)
• Score >12 = Poor candidate; surgical commissurotomy preferred

---

• Indications: DVT/PE with contraindication to anticoagulation; recurrent PE despite anticoagulation
• Access: Femoral or jugular vein; deployed in infrarenal IVC below renal veins
• Types: Permanent (Greenfield) or Retrievable (Optease, Günther Tulip - removed when anticoagulation safe)

---

1. Balloon sizing: Sizing balloon inflated across defect; waist diameter = stretched defect size
2. TEE/ICE measurement: Defect diameter measured in multiple planes
3. Device selection: For ASD - device = stretched diameter; For PDA - device = minimum diameter + 2 mm
4. Oversizing risks: Embolization, erosion, impingement on adjacent structures
5. Undersizing risks: Residual shunt, device embolization

---

1. Catheter advanced into clot (DVT, PE, peripheral arterial occlusion)
2. Thrombolytic drug (tPA / Urokinase) infused through catheter holes embedded in clot
3. Higher local drug concentration; lower systemic dose; less bleeding risk than IV thrombolysis
4. Monitored with repeat angiogram every 6-12 hours until clot dissolved
5. Used for: Massive PE, iliofemoral DVT, acute limb ischemia

---

MVA = Cardiac Output / (37.7 × Heart Rate × Diastolic Filling Period × √Mean Transmitral Gradient)

• Normal MVA: 4-6 cm²
• Mild MS: >1.5 cm²
• Moderate MS: 1.0-1.5 cm²
• Severe MS: <1.0 cm²
• Used to assess severity and response to BMV

---

COMPLETE PAPER 2 COVERAGE SUMMARY

✅ ALL TOPICS COVERED:

10 Mark Essays:

1. ✅ PTCA - Equipment, Technique, Setup, Complications
2. ✅ BMV - Technique, Hardware, Transseptal, Tamponade
3. ✅ Aortic Angiography + Peripheral Angio + Thromboembolic Disease

5 Mark Short Notes:

1. ✅ Pediatric Interventions - Device Closure (PDA/ASD/VSD)
2. ✅ IABP - Theory, Indications, Setup
3. ✅ Cardiac Pacing - Temporary + Permanent
4. ✅ Image Archival + CD Writing
5. ✅ Aortic + Pulmonary Valvuloplasty
6. ✅ Contrast Agents + Contrast Nephropathy (covered in Essay 3)
7. ✅ Peripheral Interventions (covered in Essay 3)
8. ✅ Cardiac Electrophysiology (covered in Paper 1)

3 Mark Short Answers:

1. ✅ Coarctation Angioplasty and Stenting
2. ✅ Guiding vs Diagnostic Catheter
3. ✅ Drug Eluting Stent
4. ✅ Transseptal Puncture Steps
5. ✅ Self-Expanding Stents
6. ✅ Wilkins Score
7. ✅ Vena Caval Filter
8. ✅ Sizing of Closure Devices
9. ✅ Catheter-Directed Thrombolysis
10. ✅ Gorlin Formula

---