FDA expands indication for Boston Sci's CRT-Ds

The FDA has approved an expanded indication for three of Boston Scientific's cardiac resynchronization therapy defibrillators (CRT-Ds). Along with their use in patients with Class III and IV heart failure, the devices can now be used in high-risk patients with Class I and II heart failure with left bundle branch block.

The expanded indication comes after the MADIT-CRT trial found a 57 percent reduction in risk of death and heart failure in high-risk patients with Class I and II heart failure (asymptomatic or mild) with left bundle branch block. The trial compared the efficacy of CRT-D therapy with implantable-cardioverter defibrillators (ICDs) alone. Seventy percent of the 1,820-patient trial population, which were all Class I and II, had left bundle branch block.

The FDA said that the rate of complications was considered "acceptable" for the device, adding that "physicians should adequately inform patients about potential complications."

As a condition of approval, Boston Scientific must conduct two post-approval studies. One study will evaluate complications and long-term mortality benefits of CRT-D in patients with left bundle branch block identified through the National Cardiovascular Data Registry. The other will follow patients from the original MADIT-CRT clinical study every six months for five years to assess long-term mortality benefits of CRT-D versus ICD.

In March, the FDA's Circulatory System Devices Panel unanimously recommended approval of an expanded indication for the CRT-Ds.

With the expanded approval, Boston Scientific becomes the only company with an FDA-approved CRT-D for each class of heart failure.