Medical Treatment Options in Hypertrophic Cardiomyopathy

Abstract

Hypertrophic cardiomyopathy (HCM) is a complex cardiac disease characterized by marked left ventricular hypertrophy and a great diversity in its functional alterations and clinical course [1–3]. In the 1960s, shortly after the initial contemporary descriptions of HCM, diagnosis was based on physical examination and cardiac catheterization. While these diagnostic approaches tended to emphasize the role of dynamic left ventricular outflow obstruction in the pathophysiology of the disease, some investigators had already focused on diastolic dysfunction and impaired left ventricular filling as the dominant functional alteration in HCM [4,5]. With the advent of echocardiography, it became clear that the great majority of patients have the nonobstructive form of the disease [6]. In the 1980s, metabolic, nuclear and necropsy studies drew attention to myocardial ischemia as another important functional alteration in HCM [7–10]. At present, pharmacologic therapy directed toward improving diastolic filling and possibly reducing myocardial ischemia represents the principal treatment for relieving symptoms in most patients [11] (Fig. 1). Invasive interventions focused on abolition of the outflow gradient are applied to a minority of patients (probably 5% or less of the overall HCM population) who have both outflow obstruction and severe symptoms unresponsive to medical therapy [11]. In the present discussion, we will address the issue of the pharmacologic treatment of symptoms of heart failure in HCM.