HFrEF vs HFpEF
Formal Definition
Heart failure with reduced ejection fraction (HFrEF, EF ≤40%) versus heart failure with preserved ejection fraction (HFpEF, EF ≥50%); HFrEF is characterized by impaired systolic contractile function leading to reduced forward output and compensatory neurohormonal activation (RAAS, sympathetic) that is the target of guideline-directed medical therapy (GDMT) with the four pillars (ARNI/ACEi/ARB, beta-blocker, MRA, SGLT2 inhibitor); HFpEF (also called HFpEF or diastolic HF) involves impaired ventricular relaxation and filling with relatively preserved systolic function, driven more by comorbidities (hypertension, obesity, diabetes, sleep apnea, atrial fibrillation) and structural remodeling, with fewer proven drug therapies and a focus on volume and comorbidity management.
How It's Used on the Ward
"HFrEF" (sometimes just "systolic HF" or "weak heart") vs "HFpEF" (sometimes "diastolic HF" or "stiff heart") — heart failure splits into two major phenotypes based on whether the squeeze or the relax is broken; HFrEF has many evidence-based therapies to extend life; HFpEF has fewer drug options and is heavily about treating the underlying drivers (HTN, DM, OSA, obesity).
Example
""68-year-old man with longstanding hypertension, diabetes, obesity, presenting with dyspnea on exertion, lower extremity edema. Echo: EF 55%, normal LV size, severe LV hypertrophy, grade 2 diastolic dysfunction with elevated LA pressure (E/e' 16), no significant valve disease. BNP 480. Diagnosis: HFpEF. Started SGLT2 inhibitor (empagliflozin — proven benefit in HFpEF), aggressive BP control, weight loss program, screening sleep study for OSA. Loop diuretic for symptomatic volume.""
Clinical Context
HFrEF (EF ≤40%): GDMT four pillars reduce mortality each individually and additively. (1) ARNI (sacubitril/valsartan) preferred over ACEi/ARB. (2) Beta-blocker (carvedilol, metoprolol succinate, bisoprolol — only the three evidence-based ones). (3) MRA (spironolactone, eplerenone — watch K+). (4) SGLT2 inhibitor (dapagliflozin, empagliflozin — benefit even without diabetes). Additional: loop diuretic for symptom control, hydralazine/isosorbide dinitrate (especially African American patients), ivabradine if HR ≥70 in sinus rhythm on max beta-blocker. HFpEF (EF ≥50%): Until recently no proven mortality benefit from any pharmacotherapy. Now SGLT2 inhibitors (EMPEROR-Preserved, DELIVER trials) have shown significant CV death/HF hospitalization reduction. Treat comorbidities aggressively: HTN control, weight loss (often the most impactful intervention), OSA treatment (CPAP if applicable), atrial fibrillation management, diabetes control, coronary disease management. Diuretics for symptomatic volume. Avoid: agents that worsen diastolic function (non-DHP CCBs in HFrEF, NSAIDs — fluid retention).