Heart Failure and Cardiomyopathy
Core concepts
Heart failure is a syndrome, not a single ejection fraction. HFrEF benefits from four medication pillars: ARNI, ACE inhibitor, or ARB; an evidence-based beta blocker; an MRA; and an SGLT2 inhibitor, plus diuretics for congestion. HFmrEF and HFpEF require treatment of congestion and comorbidities, and SGLT2 inhibitors have benefit across the spectrum. Identify reversible causes such as ischemia, tachycardia, thyroid disease, alcohol, toxins, infiltrative disease, and valvular disease. Cardiomyopathy classification includes dilated, hypertrophic, restrictive, arrhythmogenic, and peripartum forms. Cardiac amyloidosis is suggested by discordant wall thickness, low voltage, carpal tunnel syndrome, and elevated troponin with preserved EF.
Question traps
Do not equate diastolic dysfunction on echocardiography with clinical HFpEF. Natriuretic peptides are aides, not rules: obesity lowers them, while AF, renal failure, and age raise them. Avoid starting beta blockers during acute decompensation with congestion or hypotension. Device questions hinge on EF, QRS duration and morphology, NYHA class, and duration of optimal medical therapy. Do not miss infiltrative disease before prescribing vasodilators.
Worked example / rule of thumb
A 62-year-old with EF 30%, NYHA II symptoms, LBBB with QRS 155 ms, and three months of optimized GDMT is a CRT candidate. If QRS is 130 to 149 ms, benefit is less certain. Rule: optimize four pillars, confirm persistent symptoms, then consider devices.