Mechanisms and management of heart failure due to diastolic dysfunction.

A significant subset of patients with chronic heart failure have preserved systolic function and their symptoms are attributable to left ventricular diastolic abnormalities. In the setting of diastolic heart failure, the cardiac chambers are nondilated and have normal contractility, but left ventricular filling is impaired. This impairment in diastolic filling is related to both abnormalities of the passive elastic properties of the ventricle and impaired active relaxation as a result of any of the following: myocardial ischemia, hypertrophy, reduced beta-adrenergic tone, or increases in myocardial connective tissue. Therapy of diastolic heart failure is aimed at preventing and reducing left ventricular hypertrophy, treating elevated blood pressure, and reducing left ventricular filling pressure without reducing cardiac output. This may be achieved by maintaining sinus rhythm, slowing heart rate, and treating ischemia. Although calcium-channel blockers, beta-blockers, angiotensin-converting enzyme inhibitors, diuretics, and nitrates may improve symptoms in patients with diastolic heart failure, there are few data to indicate that these agents have an important effect on prognosis. Further studies of patients with diastolic heart failure are needed to assess its prevalence, clinical characteristics, prognosis, and response to therapy.