Learning Objective

By the end of this section, learners should be able to differentiate between HFrEF and HFpEF and explain the pharmacological strategies used in the management of chronic heart failure (CHF) based on their effects on preload, afterload, myocardial contractility, heart rate, and cardiac remodeling.

Left ventricular systolic dysfunction with reduced ejection fraction (HFrEF)—most commonly secondary to coronary artery disease—is the leading cause of heart failure. In contrast, some patients present with diastolic dysfunction and preserved ejection fraction (HFpEF), where ventricular filling is impaired despite normal contractile function.

Pharmacotherapeutic Goals in Heart Failure

Drug therapy in CHF is primarily aimed at improving cardiac function and slowing disease progression through the following mechanisms:

• Decrease Preload
  • Diuretics
  • ACE inhibitors (ACEIs)
  • Angiotensin II receptor blockers (ARBs)
  • Venodilators
• Decrease Afterload
  • ACEIs
  • ARBs
  • Arteriolar vasodilators
• Increase Myocardial Contractility
  • Digoxin
  • β-adrenergic agonists
  • Phosphodiesterase III (PDE III) inhibitors
• Reduce Heart Rate
  • β-blockers
  • Ivabradine
• Reduce Cardiac Remodeling
  • ACEIs
  • ARBs
  • Spironolactone
  • Eplerenone
  • β-blockers

Note: Pharmacologic agents that inhibit pathological cardiac remodeling are associated with improved survival in heart failure patients.

Activity

Primary Pharmacologic Treatments for CHF

• ACE Inhibitors
  • First-line therapy
  • ARBs may be used as alternatives in ACEI intolerance
• β-Blockers (e.g., metoprolol, bisoprolol, carvedilol)
  • Provide antiarrhythmic effects
  • Reduce myocardial remodeling
• Diuretics
  • Loop or thiazide diuretics reduce preload
  • Aldosterone antagonists (spironolactone, eplerenone)
  • Used in advanced CHF
  • Decrease cardiac remodeling
• Hydralazine + Isosorbide Dinitrate
  • Preferred in patients intolerant to ACEIs or ARBs
• Positive Inotropic Agents
  • β-agonists and PDE III inhibitors for acute heart failure
  • Digoxin for chronic management of HFrEF

Activity

Activity