---

Heart Failure - Complete MBBS Exam Notes

Quick Reference Mnemonics

---

1. DEFINITION

"The end stage of many forms of chronic heart disease." - Robbins & Cotran Pathologic Basis of Disease

---

2. CLASSIFICATION

A. By Ejection Fraction (EF)

HFpEF patients: tend to be older, female, obese, hypertensive, diabetic

B. ACC/AHA Stages (Progressive - CANNOT go backwards)

C. NYHA Functional Classification (Fluctuates up and down)

---

3. ETIOLOGY

"Rheumatic heart disease remains a major cause in Africa and Asia." - Braunwald's Heart Disease

---

4. PATHOPHYSIOLOGY

The 4 Major Systems Involved

1. H - Heart itself (cardiomyopathy of overload)
2. V - Vasculature (increased afterload/preload)
3. K - Kidney (RAAS activation, fluid retention)
4. N - Neurohumoral circuits (SNS, RAAS, ANP)

Compensatory Mechanisms (initially helpful, eventually harmful)

Types of Hypertrophy

Forward vs. Backward Failure

BACKWARD FAILURE                    FORWARD FAILURE
(blood backs up)                    (inadequate output)
     |                                      |
Left: pulmonary congestion          Low CO → organ hypoperfusion
Right: systemic/portal congestion   Prerenal azotemia
                                    Hypoxic encephalopathy

---

5. LEFT-SIDED HEART FAILURE

1. Perivascular/interstitial edema
2. Alveolar septal widening
3. Alveolar fluid + "heart failure cells" (hemosiderin-laden macrophages)
4. Fine basal crepitations (rales)
5. Pleural effusion (usually serous)

"Heart failure cells are hemosiderin-laden macrophages - telltale signs of previous pulmonary edema." - Robbins

---

6. RIGHT-SIDED HEART FAILURE

---

7. DIAGNOSIS

Diagnostic Flowchart (Goldman-Cecil Medicine)

1. ECG (rule out ischemia/infarction)
2. BNP/NT-proBNP: BNP >30 pg/mL or NT-proBNP >125 pg/mL = HF likely
3. Check for secondary causes: anemia, hyperthyroidism, renal failure
4. Echo + CXR + O2 saturation
5. Assess LVEF: <50% vs ≥50% directs further workup

Biomarkers - BNP/NT-proBNP

• BNP is released in response to ventricular wall tension and stretch
• Provides diagnostic AND prognostic information
• Levels correlate with NYHA class and guide therapy

CXR findings in HF:

---

8. MANAGEMENT

Overall Framework - By Stage

The "Fantastic Four" Disease-Modifying Drugs in HFrEF

Note: ARNI (sacubitril-valsartan) is preferred over ACEi in symptomatic HFrEF when tolerated.

Diuretics (for fluid overload - symptom relief, NOT mortality benefit)

Additional Agents

Device Therapy

---

9. IMPORTANT EXAM FACTS (High-Yield)

Precipitants of Acute Decompensation

Prognosis

• Median survival: 1.7 years (men) and 3.2 years (women) - Framingham Study
• 5-year survival only 25% (men) and 38% (women) - worse than many cancers
• BNP level, LVEF, NYHA class, renal function = key prognostic indicators

Key Pathology Facts (Robbins)

---

10. ONE-PAGE SUMMARY DIAGRAM

                        HEART FAILURE
                              |
          ┌───────────────────┴───────────────────┐
     SYSTOLIC (HFrEF)                        DIASTOLIC (HFpEF)
     EF < 40%                                 EF ≥ 50%
     Pump can't squeeze                       Pump can't fill/relax
     Dilated chamber                          Stiff, thick wall
     Older men, IHD                           Older women, HTN/DM
              |
   ┌──────────┴──────────┐
LEFT-SIDED HF         RIGHT-SIDED HF
(Pulmonary symptoms)   (Systemic symptoms)
Dyspnea, PND,          JVP↑, Oedema,
Orthopnoea,            Hepatomegaly,
Crepitations,          Ascites,
Pulm oedema            Nutmeg liver

COMPENSATORY MECHANISMS (FAN-H):
Frank-Starling → RAAS → SNS → Hypertrophy
→ Initially helpful, eventually HARMFUL

TREATMENT (Stage C HFrEF):
"ABMS" = ACEi/ARNI + Beta-blocker + MRA + SGLT2i
+ Diuretics (symptoms) + Device therapy

---

11. QUICK DRUG TARGETS

---