[Treatment of heart failure with phentolamine (Regitin)]

Vasodilative treatment of severe heart failure with infusions of phentolamine leads to ventricular unloading and in many cases brings about a dramatic improvement of the patient's condition. Phentolamine is the only one of the vasodilators so far used in the treatment of heart failure that has a positively inotropic effect. In contrast to sodium nitroprusside and nitroglycerin, it also increases stroke volume at normal filling pressures. Although vasodilative therapy has resulted in a notable decline in the mortality from severe heart failure among hospitalized patients, the long-term prognosis after discharge remains poor. One of the chief reasons is that there has hitherto been no effective orally administrable drug suitable for protracted therapy. Initial clinical studies with a newly developed slow-release formulation of phentolamine have shown that the preparation produces remarkably good effects in patients with chronic heart failure: systolic pressure rises, the amplitude of the blood pressure is augmented and there is an increase in urinary excretion accompanied with a corresponding reduction in weight. In practically all cases, there is a distinct decrease in the size of the heart and in pulmonary congestion.