Diastolic heart failure in the elderly and the potential role of aldosterone antagonists.

The overall incidence of heart failure increases with age, affecting up to 10% of people >65 years of age. Diastolic heart failure is also age-dependent, increasing from <15% in middle-aged patients to >40% in patients > or =70 years of age. Elderly patients usually have other co-morbid conditions such as hypertension, diabetes mellitus, coronary artery disease and atrial fibrillation that can adversely affect the diastolic properties of the heart. The clinical manifestations of diastolic heart failure are similar to those of systolic heart failure. In practice, the diagnosis is generally based on the finding of typical symptoms and signs of heart failure with preserved left ventricular ejection fraction and no valvular abnormalities on echocardiography. Altered ventricular relaxation and abnormal ventricular filling are the hallmarks of diastolic heart failure. Cardiac fibrosis and cellular disarray lead to the alterations in the diastolic properties of the heart. Diffuse foci of fibrosis in the myocardium have been reported with advancing age. Aldosterone has been shown to play a crucial role in the development of cardiac fibrosis via a direct effect on the mineralocorticoid receptors within the myocardium. Unlike the situation with treatment of systolic heart failure, few clinical trials are available to guide the management of patients with diastolic heart failure. In the absence of controlled clinical trials, patient management is based on control of the physiological factors (blood pressure, heart rate, blood volume and myocardial ischaemia) that are known to exert important effects on ventricular relaxation. Aldosterone antagonists inhibit the deposition of collagen matrix in the myocardium, thereby targeting the basic pathophysiological mechanism of diastolic dysfunction. Thus, they appear to represent a promising therapeutic approach for this condition. Currently, only small clinical trials supporting this therapy are available and large clinical trials evaluating long-term outcomes in diastolic dysfunction are therefore needed.