Heart failure is a condition where the heart cannot pump enough blood to meet the body's needs. It can be caused by conditions that damage the heart muscle such as hypertension, diabetes, and cardiomyopathy. Symptoms include dyspnea, edema, and fatigue. Over time, the heart undergoes remodeling which worsens cardiac function and leads to neurohormonal activation of the sympathetic nervous and renin-angiotensin-aldosterone systems to maintain cardiac output. Long term activation of these systems exacerbates heart failure. Treatment focuses on blocking these compensatory mechanisms using beta blockers, ACE inhibitors, ARBs, and MRAs to slow the progression of heart failure.