Congestive Heart Failure

CONGESTIVE HEART FAILURE

Congestive heart failure (CHF) refers to the presence of insufficient cardiac outputto meet the metabolic demand of the body’s tissues and organs. It is the final com-mon pathway for many cardiac diseases and has an increasing incidence in the United States. Complications include both forward failure (decreased organ per-fusion) and backward failure (passive congestion of organs). Right- and left-sided heart failure often occur together.

·            Left heart failure can be caused by ischemic heart disease, systemic hyperten-sion, myocardial diseases, and aortic or mitral valve disease. The heart has increased heart weight and shows left ventricular hypertrophy and dilatation. The lungs are heavy and edematous. Left heart failure presents with dyspnea, orthopnea, paroxysmal nocturnal dyspnea, rales, and S3 gallop.

Microscopically, the heart shows cardiac myocyte hypertrophy with “enlarged pleiotropic nuclei,” while the lung shows pulmonary capillary congestion and alveolar edema with intra-alveolar hemosiderin-laden macrophages (“heart failure cells”). Complications include passive pulmonary congestion and edema, activation of the renin-angiotensin-aldosterone system leading to secondary hyperaldosteronism, and cardiogenic shock.

·            Right heart failure is most commonly caused by left-sided heart failure, withother causes including pulmonary or tricuspid valve disease and cor pulmo-nale. Right heart failure presents with JVD, hepatosplenomegaly, dependentedema, ascites, weight gain, and pleural and pericardial effusions. Grossly, right ventricular hypertrophy and dilatation develop. Chronic passive conges-tion of the liver may develop and may progress to cardiac sclerosis/cirrhosis (only with long-standing congestion).