A 58-year-old man with a 10-year history of hypertension presents with progressive dyspnea on exertion and orthopnea. Echocardiography shows reduced ejection fraction (35%) with concentric left ventricular hypertrophy. What is the most common cause of heart failure in this patient?

Explanation

## Most Common Cause of Heart Failure with Reduced Ejection Fraction (HFrEF) **Key Point:** Coronary artery disease (CAD) is the most common cause of heart failure with **reduced ejection fraction (HFrEF)** globally, accounting for approximately 60–70% of HFrEF cases in developed nations (Harrison's Principles of Internal Medicine, 21e, Ch. 297). ### Why CAD, Not Hypertension, in This Context While hypertension is the most common **risk factor** for heart failure overall, the distinction is critical: - **Hypertension** predominantly causes **HFpEF** (preserved ejection fraction) via concentric LVH and diastolic dysfunction. - **CAD / Ischemic cardiomyopathy** is the leading cause of **HFrEF** (reduced EF), as myocardial infarction and chronic ischemia lead to systolic dysfunction and ventricular remodeling. This patient has an EF of **35%** — clearly HFrEF — making ischemic cardiomyopathy (CAD) the most likely underlying etiology. ### Pathophysiology of CAD-Induced HFrEF 1. **Myocardial ischemia / infarction** → Loss of contractile myocytes 2. **Ventricular remodeling** → Eccentric dilatation and systolic dysfunction 3. **Neurohormonal activation** (RAAS, SNS) → Further adverse remodeling 4. **Concentric LVH** can coexist due to long-standing hypertension as a comorbidity ### Epidemiology of HF Causes | Cause | Predominant EF Pattern | Prevalence in HFrEF | |-------|---|---| | **Coronary artery disease** | **HFrEF** | **60–70%** | | Hypertension | HFpEF (primarily) | ~10–15% of HFrEF | | Valvular disease | Variable | 5–10% | | Idiopathic cardiomyopathy | HFrEF | 5–10% | **Clinical Pearl:** Concentric LVH in this patient reflects the hypertensive history, but the **reduced EF of 35%** is the key discriminator — it points to ischemic cardiomyopathy (CAD) as the primary driver of systolic dysfunction. Hypertension acts as a major risk factor and comorbidity, not the primary cause of HFrEF. **High-Yield:** For NEET PG / INI-CET: - Most common cause of **HF overall** → Hypertension (as a risk factor) - Most common cause of **HFrEF specifically** → **Coronary artery disease** [cite: Harrison 21e Ch. 297; Braunwald's Heart Disease, 12e]