Heart Failure Diagnosis and Management
Diagnosis and classification
Heart failure is a clinical syndrome requiring symptoms/signs plus objective evidence, such as elevated natriuretic peptides (NPs) or imaging findings. Classify by LVEF: HFrEF ≤40%, HFmrEF 41–49%, HFpEF ≥50%. NPs are supporting, not diagnostic: obesity lowers them, while age, AF, and CKD raise them. Always integrate the clinical picture.
Guideline-directed therapy
For HFrEF, four pillars improve mortality: an ARNI (or ACEi/ARB), an evidence-based beta-blocker (carvedilol, metoprolol succinate, bisoprolol), an MRA, and an SGLT2 inhibitor. Start low and titrate every 1–2 weeks toward target or maximally tolerated doses. Loop diuretics treat congestion but do not modify mortality. Treat iron deficiency with IV iron. For HFpEF, use an SGLT2 inhibitor, diuretics for congestion, an MRA when appropriate, and aggressive comorbidity control.
Common traps
Continue GDMT even if LVEF recovers-withdrawal worsens outcomes. Allow a 36-hour washout when switching ACEi to ARNI. Avoid MRA if eGFR <30 or K >5.0. Avoid NSAIDs, thiazolidinediones, and non-dihydropyridine calcium-channel blockers in HFrEF. Do not label dyspnea as HF without objective evidence, and do not withhold therapy solely because of mild renal function decline during titration.
Worked example
A 68-year-old with progressive dyspnea has NT-proBNP 2,500 pg/mL, LVEF 28%, and jugular venous distension. Start IV furosemide for congestion, then initiate sacubitril/valsartan, carvedilol, spironolactone, and dapagliflozin before discharge, with labs in 1–2 weeks. Rule of thumb: initiate all four pillars early, then titrate; diuretics relieve symptoms but the pillars change survival.