Heart Failure

ACC/AHA Stages of HF

NY Heart Association Function Classes of HF 

Nomenclature

• HF with reduced EF (HFrEF): HF with an LVEF of ≤40%.
• HF with mildly reduced EF (HFmrEF): HF with an LVEF of 41% to 49%.
• HF with preserved EF (HFpEF): HF with an LVEF of ≥50%.
• HF with recovered EF (HFrecEF): HF with a baseline LVEF of ≤40%, a ≥ 10-point increase from baseline LVEF, and a second measurement of LVEF of >40%.

Etiologies

HFrEF

• Ischemic (approx. 2/3):
  • Obstructive CAD, previous/current myocardial infarction.
• Non-ischemic:
  • Afterload: HTN, valvulopathy
  • Arrhythmia: tachyarrhythmia, pacemaker induced
  • Myocardium:
    • Toxins (EtOH, drugs, chemo, radiation)
    • Inflammatory (autoimmune, peripartum CM, infectious, eosinophilic, giant cell, hypersensitivity).
    • Metabolic (thyroid, thiamine deficiency, DM)
    • Infiltrative (amyloid, sarcoid, hemochromatosis)
    • Stress-induced/Takotsubo
    • Genetic 
    • Idiopathic

HFpEF

• HTN, CAD, obesity, DM, CKD, infiltrative, hypertrophic cardiomyopathy, atrial fibrillation, advanced age.

Causes of Heart Failure Exacerbations (FAILURES)

• Forgetting medications or taking drugs that can worsen HF (e.g. BB, CCB, NSAIDs, TZDs), chemo (anthracyclines, trastuzumab).
• Arrhythmia/Anemia: AF, VT, PVCs; increased arrhythmia burden on device check.
• Ischemia/Infarction/Infection: respiratory infections, endocarditis, myocarditis.
• Lifestyle choices: Dietary indiscretions - high salt, EtOH, excessive fluid intake.
• Upregulation of CO: pregnancy and hyperthyroidism.
• Renal failure: acute, progression of CKD, or insufficient dialysis.
• Embolus (pulmonary) or COPD.
• Stenosis (worsening AS).

Presentation (FACES)

• Fatigue: secondary to poor O2 delivery
• Activity limitations
• Congestion: fluid buildup/volume overload (crackles, decreased basilar lung sounds d/t effusions).
• Edema: swelling in LEs, abdomen.
• Shortness of breath: DOE, orthopnea, PND, new/worsening oxygen requirement.
• Other: nausea, poor PO intake (hepatic and gut congestion), JVD, ascites, S3 or S4.

Evaluation

• Routine: CBC, CMP, magnesium.
• Perfusion/volume status: Lactate, BNP (Pro-BNP if on Entresto).
  • BNP: high negative predictive value for HF. Falsely low in obesity, falsely elevated in CKD.
• Ischemic eval: Troponin, ECG.
• HF risk factors: TSH, A1c, lipids.
• Iron studies
• CXR – differentiate other causes of dyspnea
• TTE
• Determine hemodynamic and volume profile:

Heart Failure Exacerbation Management 

• Diuresis: generally start with IV dose that is 1-2.5x total daily PO dose (e.g., a patient getting PO Lasix 80 qd should receive IV Lasix 100-200 qd; can spread out over multiple doses).
  • Aim for net negative (often 1-2L per day but patient dependent).
  • Especially early in admission, re-dose diuretics manually (rather than ordering multiple scheduled doses) to assess response.
  • Low threshold for substantial increase (double) in loop vs transition to drip if not diuresing adequately.
  • Can augment with sequential nephron blockade (thiazides, acetazolamide).
• Tele, Daily STANDING weights, 2L fluid restriction, 2g sodium diet, strict I/Os.
• Check BMP BID and Mg QD, replete K>4 and Mg>2.
• Continuation/optimization of GDMT (below).

Advanced Diuretic Management

Diuretic Conversion

• Bumetanide 1mg IV = Furosemide 40mg IV (Torsemide not available IV)
• Bumetanide 1mg PO = Torsemide 20mg PO = Furosemide 80mg PO

Diuretic Resistance & Augmentation strategies

• Can switch to lasix drip after bolus
• Consider secondary diuretics: Thiazide (most effective option), Metolazone 2.5-10mg PO (distal tubule) OR Chlorothiazide (Diuril) 250-500mg IV (if IV option needed), Acetazolamide (Diamox) 250-500mg IV (proximal tubule).

Use of SGLT2i in Acute HF

• Dapagliflozin/Empagliflozin can be initiated in hospitalized patients on the first day even if they are not diabetic.
  • Pharmacy will need to run a prior authorization to ensure affordability post-discharge.

Guideline-Directed Medical Therapy for HFrEF

General Principles:

• Starting on low dose of multiple agents over max dose of single agent.
• D/C summary should have discharge weight, GDMT, diuretic regimen, and renal function.
• Daily home weights w/ rescue diuretic plan (prn dose for 3lbs in 1 day, 5lbs in 1 week).

Device Therapies

Must be on maximally tolerated GDMT for 3 months.

• Cardiac resynchronization therapy (CRT).
  • Class I indication: NYHA class II–IV, LVEF ≤35% with QRS ≥150 ms and left bundle branch
    block (LBBB).
• ICD
  • Class I indication: primary prevention for ischemic or non-ischemic CM, NYHA class II–III with LVEF ≤35% (must have >1yr expected survival and 40+ days from MI).
  • Secondary prevention for patients who have survived cardiac arrest due to ventricular fibrillation or hemodynamically unstable ventricular tachycardia.
• Mitra Clip
  • Criteria: moderate-to-severe or severe secondary mitral regurgitation, on maximally tolerated GDMT, an EF >20% and <50%, and a left ventricle end-systolic dimension < 7cm.
• CardioMEMS
  • NYHA II-III symptoms who have had a hospitalization for HF in the past year or with elevated BNP to reduce risk of subsequent HF hospitalizations.

Guideline-Directed Medical Therapy for HFpEF

Medications overlap with HFrEF treatment (above) but outcomes are less significant.

• SGLT2 inhibitors can decrease HF hospitalizations and CV mortality.
• MRAs can decrease HF hospitalizations.
• ARBs and ARNis can be used to decrease hospitalizations.
• Diuretics as needed for congestion (no morbidity or mortality benefit).

Consider GLP1-agonists patients with concomitant obesity.

Advanced Therapies

• Indications for advanced therapies include persistent decompensated or cold heart failure despite GDMT (or inability to tolerate GDMT d/t hypotension), recurrent hospitalizations, or worsening renal/hepatic function.
• Advanced therapies are used as a bridge to either recovery, decision, or transplant.
  • Exception: inotropes may be used as a palliative measure.