ABIM Advanced HF cheat sheet

HFrEF: symptoms or signs of heart failure with LVEF ≤40%; HFmrEF: LVEF 41–49%; HFpEF: LVEF ≥50% plus elevated filling pressures or structural heart disease.

HFrEF four mortality-reducing classes: ARNI/ACEi/ARB, evidence-based beta blocker, MRA, and SGLT2 inhibitor; combination therapy is preferred over sequential titration alone.

Fick principle: cardiac output = oxygen consumption ÷ arteriovenous oxygen content difference; cardiac index = cardiac output ÷ body surface area.

Acute dyspnea: BNP <100 pg/mL or NT-proBNP <300 pg/mL makes acute heart failure unlikely; age-stratified NT-proBNP thresholds improve specificity.

Congestion: IV loop diuretic initial dose is commonly 1–2.5× the home oral dose; monitor urine output, potassium, creatinine, and weight.

Iron deficiency in HF: ferritin <100 ng/mL or ferritin 100–299 ng/mL with transferrin saturation <20%; IV iron is considered for symptomatic HFrEF.

Cardiogenic shock: SBP <90 mmHg or vasopressor requirement, hypoperfusion, cardiac index <2.2 L/min/m², PCWP >15 mmHg; SCAI stages A–E.

Atrial fibrillation in HFrEF: beta blockers are preferred rate-control agents; nondihydropyridine calcium channel blockers are avoided because of negative inotropy.

INTERMACS profiles: 1 critical cardiogenic shock; 2 progressive decline; 3 stable but inotrope-dependent; 4 resting symptoms; 5 exertion-intolerant; 6 exertion-limited; 7 advanced NYHA III.

Durable LVAD: indicated for NYHA IIIB–IV symptoms despite optimal therapy with high mortality risk; destination therapy applies to non-transplant candidates.

HeartMate 3: fully magnetically levitated centrifugal continuous-flow pump; requires warfarin plus aspirin, with typical INR target 2.0–3.0.

Continuous-flow LVAD: pump speed affects LV unloading; echocardiographic targets include midline septum, minimal aortic regurgitation, and no suction events.

Post-LVAD RV failure: low cardiac output, high CVP, hepatic congestion, and oliguria; management includes inotropes, pulmonary vasodilators, and cautious speed reduction.

LVAD GI bleeding: shear-induced acquired von Willebrand syndrome and angiodysplasia are common; management includes reducing anticoagulation, octreotide, and endoscopic therapy.

VA-ECMO: increases LV afterload; inadequate LV ejection may require venting with IABP, Impella, or atrial septostomy.

Temporary MCS: IABP augments diastolic coronary flow; Impella unloads LV; TandemHeart provides LV bypass; VA-ECMO supports oxygenation and circulation.

Heart transplant referral: end-stage HF despite optimal therapy, peak VO2 <14 mL/kg/min (or <12 on beta blocker), inotrope dependence, or recurrent hospitalizations.

Transplant contraindications: active infection, active malignancy, severe irreversible renal/hepatic/pulmonary disease, active substance use, and inadequate psychosocial support.

Fixed PVR >5 Wood units after vasodilator testing is a relative contraindication because of post-transplant right heart failure risk.

Donor heart: ABO compatibility, appropriate size match, and short cold ischemic time (commonly <4 hours) improve outcomes.

Maintenance immunosuppression: calcineurin inhibitor (tacrolimus) plus antiproliferative (mycophenolate) plus corticosteroid; mTOR inhibitors may be used for renal protection or vasculopathy.

ISHLT cellular rejection: 0, 1R, 2R, 3R; 2R or 3R usually triggers intensified immunosuppression; 1R often managed by monitoring.

Antibody-mediated rejection: capillary injury, C4d deposition, donor-specific antibodies; treat with plasmapheresis, IVIG, and rituximab.

Post-transplant prophylaxis: TMP-SMX for Pneumocystis; valganciclovir for CMV based on serostatus; monitor for allograft vasculopathy with angiography or IVUS.

PH: mPAP >20 mmHg at rest; precapillary PH has PAWP ≤15 mmHg and PVR >2 WU; postcapillary PH has PAWP >15 mmHg.

WHO groups: 1 PAH; 2 left heart disease; 3 lung disease/hypoxia; 4 chronic thromboembolic disease; 5 multifactorial/unclear mechanisms.

PVR = (mPAP − PAWP) ÷ cardiac output, in Wood units; TPG = mPAP − PAWP.

Idiopathic PAH vasoreactivity: positive test is fall in mPAP ≥10 mmHg to ≤40 mmHg with unchanged or increased cardiac output; calcium channel blockers only for positive responders.

PAH risk stratification uses WHO functional class, six-minute walk distance, NT-proBNP, echocardiography, and hemodynamics; initial combination ERA plus PDE5 inhibitor therapy is recommended for low- or intermediate-risk PAH.

CTEPH: V/Q scan is the screening test; confirm with CT pulmonary angiography and right heart catheterization; pulmonary endarterectomy is potentially curative.

Group 2 PH: treat left heart disease and congestion; PAH-specific therapies are not routinely recommended.

Acute RV failure: maintain systemic pressure with norepinephrine, use inotropes, treat congestion, correct hypoxia/hypercapnia, and avoid excessive positive-pressure ventilation.