Chronic heart failure

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Definition

  • A syndrome of volume overload and poor tissue perfusion that is caused by cardiac dysfunction and is characterized by dyspnea, fatigue, and edema
  • Two broad types:
    • Heart failure with reduced ejection fraction <40% (HFrEF or systolic dysfunction)
    • Heart failure with preserved ejection fraction (HFpEF or diastolic dysfunction)

Stages

  • Stage A: no structural heart disease or symptoms but high risk for developing HF (e.g., patients with diabetes mellitus or hypertension)
  • Stage B: structural heart disease without symptoms of HF (e.g., patients with a previous MI and asymptomatic LV dysfunction)
  • Stage C: structural heart disease with symptoms of HF (e.g., patients with a previous MI with dyspnea and fatigue)
  • Stage D: refractory HF requiring special interventions (e.g., patients with refractory HF who are awaiting cardiac transplantation).

Etiology

  • HFrEF
    • Coronary artery disease
    • Myocardial infarction
    • Hypertension
  • HFpEF
    • Myocardial infarction
    • Hypertension

Differential Diagnosis

  • Common
    • Tachyarrhythmia
    • Valvular disease
    • If CAD risk factors:
      • Coronary artery disease
      • Hypertensive cardiomyopathy
  • Other risks
    • Toxic agents: alcohol, amphetamines, cocaine, steroids, chemotherapy, heavy metals, radiation
    • Pregnancy: PPCM, pre-eclampsia, gestational diabetes
    • Inflammatory or infectious: myocarditis, sarcoidosis, infectious hypereosinophilia, giant celll lymphocytic, auto-immune diseases
    • Metabolic: diabetes, thyroid disease, adrenal insufficiency, pheochromocytoma, Cushing disease
    • Nutritional: thiamine deficiency, selenium deficiency, malnutrition, obesity
    • Infiltrative: amyloidosis, glycogen storage disease, Fabry disease
    • Hereditary: hypertrophic cardiomyopathy, ARVC, LV noncompaction, hemochromatosis
    • Acute respiratory distress syndrome (ARDS)

Epidemiology

  • 6-10% of people over age 65

Risk Factors

  • Previous episode of acute heart failure
  • Prior atrial fibrillation or coronary bypass surgery
  • Myocardial infarction
  • Coronary artery disease
  • Diabetes
  • Hypertension

Clinical Presentation

History

Signs & Symptoms

  • Cardiac exam: S3 present, abdominojugular reflux, elevated JVP
  • Respiratory exam: crackles/rales
  • Lower extremity edema
Dry Wet
Warm Less congested
Better-perfused
More congested
Better-perfused
Cold Less congested
Poorly perfused
Less congested
Poorly perfused

Investigations

  • Lab
    • Troponins
    • Natriuretic peptide (if diagnosis uncertain)
      • NT-proBNP > 450 pg/mL if age < 50 years and > 900 pg/mL if age > 50 years; <100 pg/mL helps rule it out
  • Imaging
    • Chest X-ray showing pulmonary venous or interstitial edema, cardiomegaly, or pleural effusions
  • Other
    • EKG showing new atrial fibrillation, ischemic changes, or any other abnormality
    • Echocardiography
      • Systolic heart failure
        • Reduced LV ejection fraction (LVEF)
      • Diastolic heart failure
        • E/A ratio less than 1
        • MV deceleration time > 220ms

Management

Acute heart failure

See also Acute heart failure management

  • Position the patient upright, ideally with legs over bed to aid venous pooling and decrease preload
  • Supplemental oxygen, stepping up from nasal prongs to face mask to BiPAP to intubation and ventilation, as necessary
  • Furosemide IV 40-80mg depending on severity, for volume reduction; or infusion 5-20mg/h
  • Fluid and salt restrict
  • Monitor urine output
  • Monitor daily weights
    • Target 1kg (0.5-1.5) weight loss with 3L urine output daily
  • Can escalate up to 20mg/h furosemide with 5mg BID metolazone
  • SBP < 90 / MAP < 60
    • Consider dopamine or other vasopressor
    • Consider dobutamine
  • SBP 90-100 / MAP 60-65:
    • Consider PA catheter
    • Consider dobutamine or milrinone
  • SBP >100 or MAP>65
    • Nitroglycerin transdermal patch 0.4-0.8mg/h, for afterload reduction
    • Alternate: nitroglycerin infusion titrated to maintain BP
  • Supportive care with morphine or hydromorphone, for pain and dyspnea
  • At discharge:
    • Document weight (should be lower than admission)
    • Document BNP (should be lower than admission)
  • HFpEF
    • Control blood pressure (most common cause is hypertension)
    • ACEi/ARB, especially candesartan, is probably best for ACEi
    • Consider aldosterone antagonist
    • Monitor and maintain volume status
  • Advanced HF therapies (mechanical support, transplant)
    • LVEF <25%
    • End-organ dysfunction
    • Recurrent hospitalizations 2x/12months unexplained
    • Unable to tolerate medical therapies, including hypotension
    • Diuretic refractory
    • Inotropic support
    • Pulmonary hypertension and right heart failure
    • Six-minute walk test <300m
    • Increased 1yr mortality >20%
    • Renal or hepatic dysfunction
    • Chronic hyponatremia <134 chronically
    • Cardiac cachexia
    • Unable to tolerate ADLs

Chronic heart failure

Non-pharmacologic management

  • Regular exercise 3-5 times a week for 30-45 min per session (after stress test)
  • No-added-salt diet (2-3 g/day); 1-2g/day if severe fluid retention
  • Fluid limited to 1.5 L/day to 2 L/day from all sources, if diuretics fail
  • Consider referral to multidisciplinary outpatient clinic

Comorbidities

  • Replace iron-deficiency with IV iron (improves quality of life)
  • Avoid treating diabetes with glitazones, prefer SGLT-2 inhibitors
  • Treat hypertension, especially in HFpEF

Pharmacologic treatments

  • Treat cardiovascular risk factors (hypertension, dyslipidemia, atherosclerotic disease)
    • Previous MI: ASA 81mg po daily if indicated for secondary prevention
    • Atrial fibrillation: warfarin or other anticoagulation
  • Overall approach is triple therapy: ACEi, beta-blockers, aldosterone agonists
  • Reassess NYHA class after maximizing treatment
    • NYHA I: continue
    • NYHA II-IV and sinus rhythm with HR ≥70: add ivabradine and switch ACEi to ARNI (Entresto)
    • NYHA II-IV and sinus rhythm with HR < 70bpm or AF or pacemaker: switch ACEi to ARNI (Entresto)
  • Reassess LVEF
    • If NYHA I-III and LVEF ≤35%: consider ICD/CRT
    • NYHA IV: consider hydralazine/nitrates, referral for mechanical support or transplant, refer to palliative care
  • HFrEF:
    • First-line: ACE inhibitor (second-line: ARB)
    • First-line: beta-blocker (second-line: CCB)
      • Titrate slowly, doubling dose q2-4 weeks
      • Objective improvement may take 6-12 months
    • If severe symptoms and LVEF<30%: aldosterone antagonist
    • If African-American: consider adding ISDN
    • If congestive symptoms:
      • First-line: loop diuretic at lowest minimal dose required to control symptoms
      • Second-line: consider adding thiazide or low-dose metolazone
      • Last-line: consider adding digoxin if severe symptoms or poorly-controlled atrial fibrillation
  • Monitor blood pressure while titrating up medication

Procedures

  • Cardiac resynchronization therapy is indicated when LVEF<30%, LBBB, and QRS > 150ms
  • Devices
    • ICD if EF <35%
    • CRT +/- ICD if reduced EF and LBBB
  • Implantable hemodynamic monitor (CardioMEMS)
    • Pulmonary artery pressure sensor
    • Better than daily weights for predicting heart failure exacerbations
    • Reduces hospitalizations by 30%
    • Studied in HFpEF and HFrEF
    • Expensive! $20k
  • Surgery
    • Ventricular assist devices
    • CABG
    • Transplant

Prognosis

  • 30-40% of patients die within 1 year of diagnosis and 60-70% die within 5 years
  • NYHA II have a 5-10% annual mortality rate
  • NYHA IV have a 30--70% annual mortality rate
  • MAGGIC risk score
    • Estimates 1 and 3 year survival

Palliative Care

Further Reading