Evaluation of "Early Disease" in Familial Dilated Cardiomyopathy

INTERVENTION: This study involves a randomised, double‐blind, placebo‐controlled trial to determine whether oral administration of carvedilol over a 6‐month period will reduce left ventricular dimensions in asymptomatic individuals who have a family history of dilated cardiomyopathy and echocardiographic changes that are suspected to represent early disease. CONDITION: Familial dilated cardiomyopathy PRIMARY OUTCOME: Reduction in left ventricular end‐systolic and/or end‐diastolic dimensions after 6 months of intervention when compared with baseline measurements. SECONDARY OUTCOME: Clinical evidence of disease progression, with heart failure symptoms and/or worsening of left ventricular contractile function. INCLUSION CRITERIA: Positive family history, absence of heart failure symptoms, increased left ventricular end‐diastolic diameter (>112% predicted) with or without mild impairment of systolic function (ejection fraction 40‐55%).