Double-Blind Placebo-Controlled Study of Pirfenidone, A Novel Anti-Fibrotic Drug in Symptomatic Patients With Hypertrophic Cardiomyopathy (HCM) Associated With Left Ventricular Diastolic Function Double-Blind Placebo-Controlled Study of Pirfenidone, A Novel Anti-Fibrotic Drug in Symptomatic Pati ...