This commentary discusses the rationale for evaluating cardiac resynchronization therapy in patients with less severe heart failure, noting prior trials included 86-94% NYHA class III patients.

“Cardiac resynchronisation therapy was dramatically effective in this large study population, with a 34% reduction in the risk of all-cause mortality or heart failure. The benefit is dominated by a 41% reduction in heart failure events. This results validate a new indication for cardiac resynchronisation therapy in the prevention of heart failure in at-risk asymptomatic or mildly symptomatic cardiac patients. It seems likely that this preventive CRT-D therapy will have widespread application and utilisation.”

“This is a very important trial. Previous studies have shown that the ICD saves lives. This trial demonstrates that in this population, an ICD with biventricular pacing can be expected also to improve clinical outcome as measured by hospitalization for heart failure. I anticipate that these results may improve acceptance of ICD therapy, both by patients and their physicians, in that the patient would not only live longer, but also would live better.”

“The findings from MADIT-CRT show that CRT-D effectively reduces the risk of heart failure. There is a very large population of patients with heart disease whom we believe will benefit from CRT-D therapy.”