ECG Analysis - URGENT

• Date/Time: 27/05/2026, 17:38
• HR: 68 bpm (left strip) → 157 bpm (right strip) - the heart rate jumps significantly across the strip
• VPCs noted (5 on left, 7 on right)
• Beat labels: mostly N (normal), with V beats (ventricular ectopics) and some ? (unclassifiable)

• The baseline shows narrow complex tachycardia progressing on the right side of the strip (HR 157)
• There are VPCs interspersed (labeled V) - these are ventricular premature complexes
• The morphology shows tall, peaked complexes - possible hyperacute T waves in the earlier portion, transitioning to a faster rate
• The strip appears to be a single-lead monitoring strip (Lead II), not a full 12-lead ECG

This is a rhythm strip only - a full 12-lead ECG is mandatory to evaluate for STEMI.

Clinical Assessment

1. HR escalation from 68 → 157 - sinus tachycardia or SVT developing, a known sign of hemodynamic stress during MI
2. Frequent VPCs - ventricular ectopy during acute ischemia carries risk of degeneration to VT/VF
3. Symptom duration 2 hours - within the reperfusion window

IMMEDIATE MANAGEMENT (Time-Critical)

1. Within the next 10 minutes - DO NOW

2. Blood work - STAT

• Troponin I or T (high-sensitivity) - serial at 0h and 1-3h
• CBC, CMP, coagulation (PT/INR, aPTT)
• Blood glucose
• Lipid profile
• BNP/NT-proBNP

3. Antiplatelet/Anticoagulant (once STEMI confirmed on 12-lead)

• Aspirin 162-325 mg (already given) → 81 mg/day maintenance
• Ticagrelor 180 mg loading (preferred over clopidogrel; then 90 mg BID) OR Prasugrel 60 mg load → 10 mg/day

• If going to primary PCI: UFH 70-100 U/kg IV bolus, or Bivalirudin 0.75 mg/kg IV bolus → 1.75 mg/kg/hr
• If fibrinolysis chosen: Enoxaparin 30 mg IV bolus → 1 mg/kg SQ q12h (age ≤75)

Reperfusion Strategy Decision (2025 ACC/AHA Guidelines)

Differential Diagnoses to Consider

1. STEMI (most urgent - rule in/out with 12-lead)
2. NSTEMI / Unstable Angina
3. Aortic dissection (check BP both arms, chest X-ray)
4. Pulmonary embolism (especially if HR 157 is sinus tach)
5. Pericarditis / myocarditis
6. Takotsubo (stress) cardiomyopathy - more common in middle-aged women

Regarding the Heart Rate Jump (68 → 157)

• Sinus tachycardia from pain/anxiety/hemodynamic compromise
• Paroxysmal SVT
• Atrial flutter (2:1 block often gives ~150 bpm)
• VT (if complexes are wide - check 12-lead urgently)

Bottom line: This strip shows escalating HR with VPCs in a 45F with 2 hours of chest pain - treat as ACS until proven otherwise. Get a 12-lead ECG NOW, activate your ACS protocol, and prepare for possible primary PCI. Do not delay reperfusion therapy waiting for troponin results if ST elevation is confirmed on ECG.

Post-CABG Context - Revised ECG Interpretation

What the strip shows (re-read with post-CABG lens):

Post-CABG Chest Pain - Differential Diagnosis (Ranked by Urgency)

1. Perioperative / Early Graft Failure (MOST URGENT)

• Incidence: SVG failure 3-12%, LIMA failure 1-2.5%, radial artery 3-4%
• Causes: anastomotic technical error, graft spasm, thrombosis, dissection
• 30-day mortality if perioperative MI develops: ~9%
• ECG clues to look for on 12-lead: ST elevation, new Q waves, new LBBB, T-wave inversions in the territory of the bypassed vessel

2. Post-CABG Atrial Fibrillation / Atrial Flutter

• Most common arrhythmia post-CABG (20-40% incidence, peak day 2-3)
• The HR of 157 on the right side of the strip is highly consistent with atrial flutter with 2:1 block (atrial rate ~300 → ventricular ~150)
• Causes chest discomfort due to loss of atrial kick and rapid ventricular rate

3. Postpericardiotomy Syndrome / Pericarditis

• Occurs days to weeks post-cardiac surgery
• ECG: diffuse saddle-shaped ST elevation, PR depression
• Chest pain typically positional (worse lying flat, better sitting forward)

4. Musculoskeletal / Sternal Pain

• Most common cause of chest pain after CABG overall
• Must be a diagnosis of exclusion

5. Pulmonary Embolism

• Post-surgical hypercoagulable state
• HR of 157 could represent sinus tachycardia from PE
• Look for S1Q3T3, right heart strain pattern on 12-lead

6. Aortic Dissection (rare but catastrophic - 0.05%)

• Can originate from proximal graft anastomosis site
• Tearing pain, BP differential between arms

ECG Interpretation Challenge in Post-CABG

Critical point: ECG interpretation is uniquely difficult in post-CABG patients because:

• Normal post-op changes include ST shifts, T-wave inversions, and new Q waves from cardioplegia and surgical manipulation
• These can mimic or mask true ischemia
• A baseline post-op 12-lead ECG (done immediately after surgery) must be compared with the current one
• New ST elevation in a specific coronary territory NOT present on the baseline post-op ECG = treat as graft failure until proven otherwise

• CK-MB/CK ratio >10%
• New ischemic ECG changes vs. baseline post-op ECG
• New sustained VT
• Hemodynamic deterioration

Immediate Actions Required

Do NOW:

1. Full 12-lead ECG and compare with the most recent prior ECG (especially the immediate post-op ECG)
2. Stat troponin (hs-TnI/T) + CK-MB - serial every 8 hours
3. Electrolytes - K⁺ and Mg²⁺ urgently (hypokalemia/hypomagnesemia drive VPCs and AF post-CABG)
4. Chest X-ray - effusion, pneumothorax, mediastinal widening
5. Echocardiogram - new wall motion abnormalities indicate graft territory ischemia; also rules out tamponade/effusion

If tachycardia (HR 157) is confirmed as Atrial Flutter/AF:

• Rate control: Metoprolol IV (if no contraindication, EF preserved) or Amiodarone if EF reduced
• Correct K⁺ (target >4.0 mEq/L) and Mg²⁺ (target >2.0 mg/dL)
• Anticoagulation per CHA₂DS₂-VASc score

If graft failure/perioperative MI suspected (new ST changes + troponin rise):

• Immediate coronary angiography
• Depending on findings: PCI of failed graft (preferred, 36% of cases) vs. emergency redo-CABG (32% of cases)
• Conservative management only if hemodynamically stable with incomplete/uncertain angiographic findings

Key Point for This Patient

1. Is this atrial flutter/AF (most likely at HR 157)?
2. Is there new ST elevation on a 12-lead suggesting graft failure?
3. Are troponins rising above the post-operative baseline?