A 52-year-old woman with chronic hypertension presents with left ventricular hypertrophy on echocardiography. Her 28-year-old daughter, a competitive weightlifter, also has left ventricular hypertrophy on screening echo. Which feature best distinguishes pathological hypertrophy (from hypertension) from physiological hypertrophy (from exercise)?

Explanation

## Distinguishing Pathological from Physiological Hypertrophy ### Key Morphological Difference **Key Point:** Pathological hypertrophy (from chronic hypertension) produces concentric left ventricular hypertrophy with reduced cavity size and diastolic dysfunction, whereas physiological hypertrophy (from exercise) produces eccentric hypertrophy with preserved or increased cavity size and normal function. ### Pathological Hypertrophy (Hypertension) - **Pattern:** Concentric (wall thickens, cavity shrinks) - **Mechanism:** Pressure overload → increased afterload → myocyte enlargement without proportional chamber expansion - **Functional consequence:** Diastolic dysfunction (impaired relaxation, reduced compliance) - **Ejection fraction:** Initially preserved, but may decline with progression - **Prognosis:** Risk of heart failure, arrhythmia, sudden death ### Physiological Hypertrophy (Exercise) - **Pattern:** Eccentric (wall thickens, cavity enlarges proportionally) - **Mechanism:** Volume overload → increased preload → myocyte enlargement with chamber dilation - **Functional consequence:** Maintained or enhanced systolic and diastolic function - **Ejection fraction:** Normal or supernormal - **Prognosis:** Benign, reversible with detraining ### Comparison Table | Feature | Pathological (HTN) | Physiological (Exercise) | |---------|-------------------|------------------------| | **Stimulus** | Pressure overload | Volume overload | | **Pattern** | Concentric | Eccentric | | **Wall thickness** | Increased | Increased | | **Cavity size** | Reduced | Normal/Increased | | **Wall:Cavity ratio** | Increased | Normal | | **Diastolic function** | Impaired | Normal | | **Systolic function** | Initially preserved | Normal/Enhanced | | **Reversibility** | Partial (with treatment) | Complete (with detraining) | ### Clinical Pearl **Clinical Pearl:** The **cavity size** is the single best discriminator: pathological hypertrophy narrows the LV cavity (concentric), while physiological hypertrophy maintains or enlarges it (eccentric). Diastolic dysfunction is the functional hallmark of pathological hypertrophy and a major cause of heart failure with preserved ejection fraction (HFpEF). ### High-Yield Memory Aid **Mnemonic:** **COPE** for Concentric (pathological) vs. **EAVE** for Eccentric (athletic): - **C**oncentric = **C**avity shrinks (pathological) - **E**ccentric = **E**nlarged cavity (exercise) [cite:Robbins 10e Ch 1]