Management of Heart Failure

SUMMARY:

Heart failure (HF) is a broad term that encompasses many different etiologies and degrees of cardiac dysfunction, but generally refers to impairment of blood flow through the heart. Americans over 40 have a 20% lifetime risk of developing HF. It is associated with considerable morbidity and mortality, and accounts for approximately 1M hospitalizations annually; it is also a major cause of hospital readmission. The 2013 ACC/AHA Guideline for the Management of Heart Failure (with focused updates in 2016 and 2017) offers a comprehensive guide to treating this common condition.

• Risk Factors
• Diagnosis of HF
• Workup at Time of Diagnosis
• Key Points
  • Terminology
  • Stages and Classes of HF
  • Treatment Considerations – GDMT
  • HFpEF Management
  • Dietary Recommendations
  • Other Considerations
• Learn More – Primary Sources

Risk Factors

• Hypertension is the primary modifiable risk factor
• Treating chronic hypertension leads to 50% reduction in risk of developing HF
• Other risk factors
  • Coronary artery disease (CAD) | Diabetes | Metabolic syndrome | Smoking | Alcohol | Illicit drug use (cocaine, amphetamines)

Diagnosis of HF

• Primarily a clinical diagnosis
• Cardinal symptoms
  • Shortness of breath | Exercise intolerance | Fatigue | Edema

Workup at Time of Diagnosis 

• Imaging
  • Basic: EKG | Chest X-ray | Echocardiogram
  • New HF with high suspicion for CAD: Coronary angiography +/- revascularization
  • New HF with known CAD: Non-invasive imaging to detect myocardial ischemia (e.g. nuclear myocardial perfusion scan)
• Labs
  • CBC | Tests of kidney and liver function | Electrolytes | Lipids | TSH | Urinalysis | BNP
  • New evidence suggests screening BNP in patients at risk for HF (i.e. with ≥1 risk factors) “can be useful” in preventing clinical HF

KEY POINTS:

Terminology

• HF with reduced EF (HFrEF or ‘systolic’ HF) vs. HF with preserved EF (HFpEF or ‘diastolic’ HF)
  • HFrEF: EF≤40%
  • HFpEF: EF>40% | Accounts for half of all HF

Note: HFrEF and HFpEF are not mutually exclusive | Patients often have combined systolic and diastolic dysfunction

Stages and Classes of HF

Guideline-directed medical therapy (GDMT) Is Tailored According to Severity of Disease

• ACC/AHA stages of HF: Considers symptoms as well as structural cardiac abnormalities
  • A: At risk for HF, no structural heart disease
  • B: Structural heart disease, no symptoms of HF
  • C: Structural heart disease with symptoms of HF
  • D: Refractory HF (not responding to standard medical therapy)

• New York Heart Association (NYHA) classes of HF: Subjective, based on symptomatology
  • I: No limitation of physical activity
  • II: Slight limitation of physical activity (OK at rest, symptomatic with “ordinary” activity)
  • III: Marked limitation of physical activity (OK at rest, symptomatic with “less than ordinary” activity)
  • IV: Symptomatic at rest or with any level of physical activity

Treatment Considerations – GDMT

• GDMT recommendations based on large RCTs showing morbidity and mortality benefit for Stages B-D HFrEF only
  • Little evidence of benefit in HFpEF
• GDMT
  • Reduces morbidity and mortality
  • Improves symptoms and quality of life (QOL)
  • Decreases hospitalizations
• Some therapies limit cardiac remodeling and lead to improvements in ejection fraction (EF) over time

ACE inhibitors (ACEI): Associated with mortality benefit

• Examples
  • lisinopril, enalapril, fosinopril        
• Switch to ARB (losartan, valsartan) if chronic cough develops (20% of patients)
• Reassess renal function and electrolytes within 1 to 2 weeks after initiation of ACEI or ARB
• Do not combine ACEI and ARB
• In NYHA class II to III patients tolerating ACEI/ARB, switch to Entresto (valsartan/sacubitril)

Beta blockers:  Associated with mortality benefit

• Examples
  • Carvedilol | Bisoprolol | Metoprolol succinate (not tartrate)
• General rule for dosing
  • ‘Start low, go slow’ | Titrate up to maximum tolerated dose

Aldosterone antagonists: Mortality benefit for NYHA II-IV with EF≤35%

• Examples
  • Spironolactone, eplerenone
• Major risk is hyperkalemia
  • Start only if GFR >30 ml/min and K+ <5
  • Reassess renal function and electrolytes 3 and 7 days after starting

Loop diuretics: Indicated for Stages C-D for relief of symptoms due to fluid overload; no known effect on mortality

• Examples
  • Furosemide | Bumetanide | Torsemide
• Titration
  • Largely based on symptoms and clinical assessment of volume status (weight, urine output, BNP)
  • Most patients will require chronic fixed doses to maintain euvolemia

Other medications

• Digoxin
  • For persistent symptoms despite GDMT | Shown to decrease hospitalizations
• Hydralazine + isosorbide dinitrate: For persistent symptoms despite GDMT in NYHA III-IV African American patients
• Ivabridine
  • Can reduce HF hospitalizations in a small subset of patients: NYHA class II-III with EF≤35% on GDMT and sinus rhythm with resting HR≥70 bpm
  • Omega-3 fatty acids: “reasonable to use as adjunctive therapy” for NYHA II-IV HFrEF or HFpEF

Drugs to avoid

• Calcium channel blockers
  • Can worsen HF (particularly non-dihydropyridines due to their negative inotropic effect); amlodipine may be OK
  • NSAIDs: Cause sodium and water retention
  • Thiazolidinediones: Increased incidence of HF events

HFpEF Management

• Recommendations are limited to BP control
  • First line: ACEI or ARB
  • Diuretics for symptom management
• Mortality benefit of GDMT for HFrEF when applied to HFpEF has not been convincingly demonstrated

Dietary Recommendations

• Sodium restriction
  • Stages A and B: <1.5 g/day
  • Stages C and D: <3 g/day
• Fluid restriction: <1.5-2L/day only recommended in Stage D (refractory) HF

Other Considerations

• Indications for CABG
  • HFrEF or HFpEF with angina despite GDMT or significant multivessel disease

• Indications for ICD placement for primary prevention of sudden cardiac death
  • EF≤35% (NYHA II-III) or EF≤30% (NYHA I)
  • On GDMT
  • Expected survival ≥1 year

• Repeat echocardiogram in a patient with ≥1 of the following
  • Significant change in clinical status
  • Experienced or recovered from a clinical event
  • Received treatment, including GDMT, with potentially significant effect on cardiac function

• HF and obstructive sleep apnea
  • CPAP “can be beneficial” to improve EF and functional status

• HF and anemia
  • NYHA II-III and iron deficiency (ferritin<100 ng/mL), IV iron “might be reasonable” to improve functional status and quality of life

Learn More – Primary Sources:

2013 ACCF/ACA Guideline for the Management of Heart Failure

2016 ACC/AHA/HFSA Focused Update on New Pharmacologic Therapy for Heart Failure

2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/ACA Guideline for the Management of Heart Failure