Cardiomyopathy (short note)

Definition: structural and functional myocardial disease in the absence of coronary, hypertensive, valvular or congenital disease sufficient to explain it.

Five phenotypes (2023 ESC): dilated, hypertrophic, restrictive, arrhythmogenic right ventricular, and non-dilated left ventricular cardiomyopathy.

Dilated: dilated ventricle with reduced ejection fraction. Causes — idiopathic/familial, alcohol, chemotherapy, myocarditis, tachycardia-induced, thyroid, peripartum.

Hypertrophic: autosomal dominant sarcomere mutation with myocyte disarray; may obstruct the outflow tract. In older adults it may be mistaken for aortic stenosis; digoxin and diuretics worsen it.

Restrictive: stiff ventricles with preserved systolic function and biatrial enlargement. In the elderly the dominant cause is cardiac amyloidosis; endomyocardial fibrosis is important in Indian practice.

Clinical features: dyspnoea, fatigue, palpitations, syncope, embolism, arrhythmia and sudden death; right-sided congestion predominates in restrictive disease.

Red flags for amyloidosis in an older patient: HFpEF with marked left ventricular thickening, low ECG voltages, bilateral carpal tunnel syndrome, lumbar canal stenosis, and hypotension on standard heart failure drugs.

Diagnosis: ECG, echocardiography (including global longitudinal strain showing apical sparing), cardiac MRI with late gadolinium enhancement, 99mTc-PYP/DPD bone scintigraphy, serum free light chains and immunofixation, genetic testing, biopsy if needed.

Treatment: phenotype-directed — HFrEF four-pillar therapy and devices in dilated disease; beta blocker/verapamil, disopyramide and septal reduction in obstructive hypertrophic disease; cautious diuresis, arrhythmia control and disease-modifying therapy in amyloidosis.

Family implications: genetic counselling and cascade screening of first-degree relatives in inherited forms — a point examiners often expect but candidates omit. Latest Updates and Current Practice Update (concise) 2023 ESC Cardiomyopathy Guideline introduced the non-dilated left ventricular cardiomyopathy phenotype and mandated multimodality imaging plus genetic testing with family cascade screening. Three approved drugs for transthyretin cardiac amyloidosis — tafamidis, acoramidis (2024) and vutrisiran (2025) — have converted a formerly untreatable cause of HFpEF in the elderly into a treatable one; the textbooks predate all three. Mavacamten and aficamten (cardiac myosin inhibitors) are new first-in-class oral therapies for obstructive hypertrophic cardiomyopathy.