What it is:A clinical syndrome where the heart can't deliver enough cardiac output to meet the body's needs, confirmed by elevated natriuretic peptides or objective evidence of congestion. It's not one disease, it's the common endpoint of many.
The core problem:Low cardiac output triggers compensatory neurohormonal activation (SNS, RAAS, vasopressin). Those compensations feel helpful short-term but are what actually drive the disease forward. Every effective HF drug works by blocking a compensation, not by boosting the heart.
What you do about it:In HFrEF, start all four pillars early at low dose, then titrate. Don't max one before adding the next.
She framed HF as a "self-feeding decompensation loop"and stressed "there is no going backwards on this path."Once a patient is HFrEF, they're always HFrEF even if EF improves. Improved EF is nota reason to stop therapy. That distinction showed up repeatedly in her slides.
Three separate classification systems, and they answer different questions. Mixing them up is a classic exam trap.
| System | Answers | Categories |
|---|---|---|
| LVEF | What kind of pump problem? | HFrEF ≤40% · HFmrEF 41–49% · HFpEF ≥50% |
| NYHA Class | How bad are symptoms today? (can move both ways) | I no limitation · II slight · III marked · IV symptoms at rest |
| ACC/AHA Stage | Where are they on the disease continuum? (only moves forward) | A at risk · B pre-HF (structural, no sx) · C symptomatic · D advanced/refractory |
NYHA is reversible. Stage is not.A patient can go NYHA III → NYHA II with good diuresis. A Stage C patient never returns to Stage B. Stage tells you what therapy they qualify for; NYHA tells you how they're doing on it.
Understand this section and the entire treatment algorithm becomes obvious instead of memorized.
Something reduces cardiac output. Common culprits are coronary artery disease and hypertension (the two leading causes). Systolic dysfunction means the ventricle can't contract adequately: lost muscle from MI, dilated cardiomyopathy, or hypertrophy from pressure or volume overload. Diastolic dysfunction means it can't fill: stiff ventricle, hypertrophy, infiltrative disease, ischemia, or pericardial disease.
| Compensation | Driven by | Effect | Why it hurts long-term |
|---|---|---|---|
| ↑ Free water reabsorption | RAAS, vasopressin | ↑ Preload | Congestion, pulmonary edema |
| ↑ Sodium reabsorption | RAAS | ↑ Preload | Volume overload, edema |
| ↑ Venous constriction | RAAS, SNS | ↑ Preload | Worsens congestion |
| ↑ Heart rate | SNS | ↑ CO | ↑ O₂ demand, less filling time, arrhythmia |
| ↑ Contractility | SNS | ↑ CO | Catecholamine-induced myocyte necrosis |
| ↑ Arterial constriction | RAAS, SNS | ↑ Afterload | Heart works harder against higher SVR |
Look at that table and read the drug classes off it. ACEi/ARB/ARNIblock RAAS. Beta blockersblock SNS. MRAsblock aldosterone's fibrosis and remodeling. SGLT2iunload volume and shift myocardial metabolism. Diureticsattack preload directly. Nothing on this list makes the heart squeeze harder, and that's the point.
Chronic neurohormonal activation, mainly angiotensin II, norepinephrine, aldosterone, and vasopressin, drives myocyte injury, oxidative stress, inflammation, and extracellular matrix changes. The ventricle changes size, shape, and structure. That's ventricular remodeling, and it makes both systolic and diastolic function worse, which drives more remodeling. The self-feeding loop.
Myocardial ischemia or MI, pulmonary infection, dietary or medication nonadherence, and inappropriate medication use. Drugs can precipitate HF through negative inotropy, direct cardiotoxicity, or sodium and water retention (think NSAIDs, thiazolidinediones, some antiarrhythmics, certain chemo agents).
Presentation ranges from completely asymptomatic to cardiogenic shock. The two primary symptoms are dyspnea (especially on exertion)and fatigue, both producing exercise intolerance.
| Category | Findings |
|---|---|
| Pulmonary | Dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea (PND), tachypnea, cough, crackles |
| Congestion | Peripheral edema, JVD, hepatojugular reflux, hepatomegaly, ascites, weight gain |
| Low output | Fatigue, cool extremities, narrow pulse pressure, altered mental status, decreased urine output |
| Nonspecific / GI | Nocturia, anorexia, early satiety, bloating, nausea, abdominal pain, hemoptysis, weight loss |
| Exam | S3 gallop, cardiomegaly, tachycardia, Cheyne–Stokes respiration |
Extreme breathlessness with anxiety, sometimes coughing pink frothy sputum. This is an emergency presentation, not a clinic problem.
Orthopnea= dyspnea lying flat, relieved by sitting up, happens immediately. Quantify it by pillows. PND= wakes them up 1–2 hours into sleep gasping. Different timing, different mechanism, both mean congestion.
Diagnosis is clinical (signs and symptoms) plus objective confirmation. History, physical, and targeted labs.
| Marker | Ambulatory | Hospitalized / decompensated |
|---|---|---|
| BNP | >35 pg/mL | >100 pg/mL |
| NT-proBNP | >125 pg/mL | >300 pg/mL |
Its strength is ruling out. A low BNP in a dyspneic patient argues hard against HF as the cause. In ADHF, BNP <100 or NT-proBNP <300 is negatively predictive for congestion. Also note: sacubitril/valsartan raises BNP (neprilysin normally degrades it) but does notraise NT-proBNP, so NT-proBNP is the one to trend on ARNI.
This is the core of the chapter and the highest-yield thing on the page. All four are mortality-reducing in HFrEF. Modern practice starts all four at low dose thentitrates, rather than maximizing one before starting the next.
Blocks RAAS. ARNI preferred over ACEi/ARB unless cost or access is a barrier.
Blocks SNS. Only 3 agents proven: carvedilol, metoprolol succinate, bisoprolol.
Blocks aldosterone-driven fibrosis, remodeling, inflammation.
Benefit is independent of diabetes. No titration needed.
Her slides pushed the rapid sequencingapproach: initiate all four classes at low dose within the first days (SGLT2i needs no titration at all), then titrate ARNI, beta blocker, and MRA over the following weeks. She cited early relative risk reductions of roughly −42%for CV death or HF hospitalization (ARNI), −25%mortality (beta blocker), −37%(MRA), and −58%for CV death, ER visit, or HF hospitalization (SGLT2i).
The point:four low doses beat one maxed-out drug. Waiting to titrate one pillar to target before adding the next costs lives.
| Trial | Drug | Population | Key result |
|---|---|---|---|
| CONSENSUS | Enalapril | NYHA IV | 6 mo RR ↓40%; NNT 6to prevent 1 death |
| SOLVD | Enalapril | NYHA II–III | 12 mo RR ↓16%; NNT 23 |
| PARADIGM-HF | Sac/Val vs enalapril | NYHA II–IV | Death or hosp 21.8% vs 26.5%, HR 0.80; NNT 22 |
| RALES | Spironolactone | NYHA III–IV | Mortality HR 0.70; NNT 9; gynecomastia 9% of men |
| EMPHASIS-HF | Eplerenone | Mild HF | NNT 19 |
| DAPA-HF | Dapagliflozin | EF ≤40% | Worsening HF or CV death HR 0.74 |
| EMPEROR-Reduced | Empagliflozin | EF ≤40% | HR 0.75; HF hosp HR 0.69 |
| DELIVER | Dapagliflozin | EF >40% | HR 0.82 - extended SGLT2i to HFpEF |
| EMPEROR-Preserved | Empagliflozin | EF >40% | HR 0.79 |
| FINEARTS-HF | Finerenone | HFmrEF / HFpEF | Worsening HF or CV death HR 0.84 |
Before CONSENSUS and SOLVD, HF therapy was onlydigoxin and diuretics, and about 75% of patients died within 5 years of diagnosis. Those were the first trials to show a mortality benefit. That's why RAAS blockade is pillar one.
mortality benefitmarks regimens proven in large trials to reduce mortality.
| Class / Drug | Start | Target |
|---|---|---|
| ARNI | ||
| Sacubitril/valsartan (Entresto) | 49/51 mg BID | 97/103 mg BIDmortality |
| ACE inhibitors | ||
| Enalapril | 2.5 mg BID | 10–20 mg BID mortality |
| Lisinopril | 2.5–5 mg daily | 20–40 mg daily mortality |
| Ramipril | 1.25–2.5 mg daily | 10 mg daily mortality |
| Captopril | 6.25 mg TID | 50 mg TID mortality |
| ARBs (only these 3 are guideline-recommended) | ||
| Candesartan | 4–8 mg daily | 32 mg daily mortality |
| Valsartan | 20–40 mg BID | 160 mg BID mortality |
| Losartan | 25–50 mg daily | 150 mg daily mortality |
| Beta blockers (only these 3 proven) | ||
| Carvedilol | 3.125 mg BID | 25 mg BID mortality |
| Metoprolol succinate CR/XL | 12.5–25 mg daily | 200 mg daily mortality |
| Bisoprolol | 1.25 mg daily | 10 mg daily mortality |
| MRAs | ||
| Spironolactone | 12.5–25 mg daily | 25–50 mg daily mortality |
| Eplerenone | 25 mg daily | 50 mg daily mortality |
| SGLT2 inhibitors | ||
| Dapagliflozin / Empagliflozin | 10 mg daily | 10 mg daily (no titration) |
| Loop diuretics (symptoms only, no mortality benefit) | ||
| Furosemide | 20–40 mg once–twice daily | 20–160 mg once–twice daily symptoms |
| Torsemide | 10–20 mg daily | 10–80 mg daily symptoms |
| Bumetanide | 0.5–1 mg once–twice daily | 1–2 mg once–twice daily symptoms |
| Select add-ons | ||
| Hydralazine + isosorbide dinitrate | 37.5 / 20 mg TID | 75 / 40 mg TID mortality |
| Digoxin | 0.125–0.25 mg daily · target level 0.5–0.9 ng/mL | |
| Ivabradine | 5 mg BID with meals | 5–7.5 mg BID |
| Vericiguat | 2.5 mg daily | 10 mg daily |
ACE inhibitorsreduce angiotensin II and aldosterone, and also block bradykinin breakdown. That bradykinin accumulation is what causes the dry cough (15–20% of patients, the most common reason for discontinuation) and contributes to angioedema (~1%, potentially life-threatening).
ARBsblock AT₁ directly and don't touch bradykinin, so less cough and lower angioedema risk. Only candesartan, valsartan, and losartan have HF trial evidence. Important: ARBs are nota workaround for hypotension, hyperkalemia, or renal dysfunction from an ACEi, because they cause those just as readily.
ARNI (sacubitril/valsartan)adds neprilysin inhibition. Neprilysin degrades bradykinin and endogenous vasodilator/natriuretic peptides, so blocking it enhances vasodilation, diuresis, and natriuresis while suppressing renin and aldosterone. Preferred over ACEi/ARB in HFrEF.
Stop an ACE inhibitor 36 hoursbefore starting ARNI. No washout needed coming from an ARB. Never give ARNI concurrently with an ACEi or another ARB. Contraindicated with any history of ACEi/ARB angioedema, and in pregnancy.
Angioedema note from your lecture:Dunne flagged that bradykinin-mediated angioedema is notan allergic reaction, so it isn't treated like one. Angioedema is somewhat more frequent with sacubitril/valsartan than enalapril (0.5% vs 0.2%).
Beta blockers cut myocardial oxygen demand, reduce remodeling, protect against catecholamine-induced myocyte necrosis, guard against arrhythmia, and lower death and hospitalization.
Only carvedilol, metoprolol succinate, and bisoprololreduced mortality in large HF trials. This is a class where you cannot substitute freely. Metoprolol tartrateis not interchangeable with succinate here.
She broke them down by receptor activity, which explains tolerance differences: carvedilolis third-generation with β1, β2, andα1 blockade plus nitric oxide activity (more BP lowering, more dizziness). Metoprolol succinateand bisoprololare second-generation, β1-selective only (better if bronchospasm or hypotension is the limiting factor). Knowing this lets you tailor by tolerance rather than guess.
Titration:Start very low, double no more often than every 2 weeks. Only titrate when the patient is euvolemic and compensated, otherwise you trigger an exacerbation. MOCHA showed a linear dose-response for LV function and mortality, meaning everytitration step adds benefit, but dizziness and bradycardia scale linearly too.
Most patients feel sluggish or fatigued for 3–7 daysafter each dose increase. Warn them upfront or they'll stop the drug. Also tell them the goal is survival and disease modification, not feeling better immediately - symptoms may transiently worsen during initiation.
Absolute contraindications:uncontrolled bronchospastic disease, symptomatic bradycardia, advanced heart block without pacemaker, acute decompensated HF. Can be used cautiously in COPD, well-controlled asthma, or asymptomatic bradycardia.
MRAs block mineralocorticoid receptors. The benefit isn't really diuretic (effects at these doses are minimal), it's blocking aldosterone-driven cardiac fibrosis, collagen deposition, remodeling, inflammation, and oxidative stress. They also lower sudden cardiac death.
| Spironolactone | Eplerenone | Finerenone | |
|---|---|---|---|
| Structure | Flat, steroidal | Flat, steroidal | Bulky, non-steroidal |
| MR potency | +++ | + | +++ |
| MR selectivity | + | ++ | +++ |
| Kidney: heart distribution | >6:1 | ~3:1 | 1:1 |
| Active metabolites | Yes | No | No |
| Half-life | ≥24 h | 4–6 h | 2.8 h |
| Sexual side effects | ++ | + | – |
| Hyperkalemia risk | High | High | Moderate |
Why spironolactone causes gynecomastia:poor MR selectivity means it also hits androgen and progesterone receptors. RALES saw gynecomastia in 9% of men. Eplerenone is the swap when that happens.
"MRAs will drop BP too much so you can't use them if BP is low."Actually false in HF. Patients with high baseline BP drop, but those with low baseline BP tend to increase. The caveat is over-diuresis causing dehydration, which resolves with hydration. Her framing: HTN and HF are not the same creature.
Avoid ifK⁺ >5.0 mEq/L, significant renal impairment, or history of severe hyperkalemia. Start lower (spironolactone 12.5 mg) in older adults, diabetes, or CrCl <50.
They block glucose and sodium reabsorption in the proximal tubule, producing osmotic diuresis and natriuresis, lowering arterial pressure and stiffness, and shifting the myocardium toward ketone-based metabolism. FDA approved for HF of all types, proteinuric kidney disease, diabetes, and ASCVD prevention. Benefit in HF is present with or without diabetes.
Starting an SGLT2i causes a small early rise in serum creatinine. This is notkidney damage - it's the opposite. Reduced intraglomerular pressure means less hyperfiltration across fewer nephrons; more nephrons share the work at a lower forced rate. Long-term, HF patients on SGLT2i have slowerrenal decline. Just confirm the rise isn't from excess urine output and volume depletion.
Counseling:weigh daily and call if weight starts dropping unexpectedly; rise from sitting or lying slowly since orthostasis can occur with over-diuresis.
Diuretics:For congestion only. They relieve symptoms but do notslow progression or prolong survival, so patients without fluid retention don't need them. Loop diuretics are the workhorse and keep working in renal impairment (may need higher doses). Thiazides alone are too weak, but adding metolazone or a thiazide to a loop produces powerful sequential nephron blockade. Watch for hypovolemia, hypotension, hyponatremia, hypokalemia, hypomagnesemia, hyperuricemia, renal dysfunction.
Hydralazine + ISDN:ISDN is a venodilator reducing preload; hydralazine is an arterial dilator reducing SVR and raising stroke volume. Guidelines recommend adding this to Black patients with HFrEFstill symptomatic on ARNI, beta blocker, MRA, and SGLT2i. Also useful when ACEi/ARB can't be used due to renal insufficiency, hyperkalemia, or hypotension. Barriers: TID dosing, frequent headache/dizziness/GI upset, and cost of the combination product.
Ivabradine:Inhibits the Ifcurrent in the SA node, slowing rate without touching AV conduction, BP, or contractility. Indicated when LVEF ≤35%, sinus rhythm, resting HR ≥70 bpm, and already on maximally tolerated beta blocker (or beta blocker contraindicated). Titrate the beta blocker first- it has the mortality data. Titration: after 2 weeks, if HR 50–60 continue; if >60 increase to 7.5 mg BID; if <50 or symptomatic bradycardia reduce by 2.5 mg BID or stop. Adverse effects: bradycardia, atrial fibrillation, visual disturbances (phosphenes).
Digoxin:Positive inotrope, but its HF benefit is neurohormonal - dampens excess SNS activity, increases parasympathetic tone, lowers HR, improves diastolic filling. Not first line. Reduces hospitalizations and symptoms; mortality effect is neutral at best. Target level 0.5–0.9 ng/mL. Most patients with normal renal function reach that on 0.125 mg/day. Drop to 0.125 mg every other day with renal impairment, low body weight, advanced age, or interacting drugs like amiodarone.
Vericiguat:Soluble guanylate cyclase stimulator, enhances nitric oxide signaling to raise cGMP. Modest reduction in CV death or HF hospitalization; unexplained excess anemia. Its niche is high-risk patients who can't tolerate standard GDMT, since it has minimal hemodynamic, renal, and electrolyte effects. Not indicated in HFpEF.
Treatment centers on controlling heart rate and blood pressure, relieving ischemia, reducing volume, and restoring sinus rhythm in atrial fibrillation. Many of the same drugs appear, but the rationale and dosing differ.
Nitrates reduceexercise capacity in HFpEF and don't improve quality of life or NT-proBNP. Worsening HF and presyncope/syncope are more frequent. Without a separate indication like angina, they offer no benefit here. This is a common distractor.
New or worsening signs and symptoms, usually from volume overload, low cardiac output, or both, requiring an ED visit or hospitalization. Goals: relieve symptoms, stabilize hemodynamics, reduce short-term mortality, and get the patient discharged compensated on oral therapy.
Classify by volume status(wet = congested, dry = euvolemic) and perfusion(warm = adequate CO, cold = hypoperfused). This single 2×2 drives initial therapy.
| Subset | Picture | Approach |
|---|---|---|
| I - Warm & Dry | Compensated, perfusing | Optimize oral GDMT, look for another cause of symptoms |
| II - Warm & Wet | Congested, still perfusing (most common) | IV loop diuretic; add vasodilator if BP allows |
| III - Cold & Dry | Hypoperfused, not congested | Cautious fluid; consider inotrope if still low output |
| IV - Cold & Wet | Congested andhypoperfused - sickest | Assess SBP: ≥90 vasodilator + diuretic; <90 inotrope then diuresis |
| Volume overload ("wet") | Low output ("cold") | |
|---|---|---|
| Symptoms | Dyspnea, orthopnea, PND, ascites, poor appetite, nausea, early satiety, edema, weight gain | Altered mental status, fatigue, similar GI symptoms, decreased urine output |
| Signs | Crackles, elevated JVP, hepatojugular reflux, S3, peripheral edema | Tachycardia, hypotension (or hypertension), narrow pulse pressure, cool extremities, pallor, cachexia |
Increase the loop dose, switch to continuous infusion, add a diuretic with a different mechanism (metolazone/thiazide), add an IV vasodilator or IV inotrope, and in select patients add mechanical circulatory support.
| Parameter | When | Watching for |
|---|---|---|
| SCr and K⁺ | Baseline, then 1–2 weeks after starting or increasing any RAAS agent (ACEi/ARB/ARNI/MRA) | Renal decline, hyperkalemia. Dunne: if K⁺ elevated, consider a potassium binder rather than abandoning the drug |
| Blood pressure | Baseline and each titration | Symptomatic hypotension - the most common titration limiter |
| Heart rate | Each beta blocker or ivabradine change | Bradycardia; ivabradine target resting HR 50–60 |
| Daily weight | Every day at home, same time | Fluid shifts - earliest warning of decompensation |
| Symptoms / NYHA | Every visit | Functional trajectory |
| LVEF | After GDMT optimization | Improvement, or worsening that warrants escalation and advanced-therapy referral |
| NT-proBNP | Periodically, and in ADHF | Congestion. Use NT-proBNP not BNP if on ARNI |
| Digoxin level | Steady state, with dose or renal changes | Target 0.5–0.9 ng/mL |
| Electrolytes on diuretics | Regularly | Hypokalemia, hypomagnesemia, hyponatremia |