July 10, 2001 (Gaithersburg, Md.) — An FDA expert panel today recommended approval of a breakthrough implant that may allow patients with advanced heart failure to feel better, walk farther, and be more active.
In a 7-0 vote, the agency’s Circulatory System Devices Advisory Committee endorsed the availability of the device, developed by Medtronic and called the InSync cardiac resynchronization therapy system. InSync helps a struggling heart pump more efficiently.
“It’s a big deal,” says Julie Swain, MD, acting chair of the panel and a NASA official. If promising data hold up, she says, it will be a significant addition to cardiologists’ arsenal of treatments for patients with serious heart problems.
Patients who suffer heart failure have difficulty pumping enough blood with oxygen to meet their body’s needs. This results in fatigue and an inability to participate in normal physical activities. Heart failure is often caused by coronary artery disease but can also stem from high blood pressure, clogged arteries, diabetes, infection, and other causes.
About five million Americans have heart failure, and about 500,000 new cases are diagnosed annually. Well over 80% of heart failure patients are senior citizens, and heart failure is Medicare’s leading hospitalization diagnosis.
Most with the condition are on medications such as ACE inhibitors and beta-blockers. More dire cases of heart failure can require valve replacement, implanted defibrillators, or heart transplant.
The company says the device could benefit nearly 750,000 patients who are not eligible for an implantable cardioverter defibrillator, or ICD, and have only been managed by heart failure drugs.
Results presented to the FDA panel reflected a rigorously controlled study of 532 patients who received the device at 44 North American centers. Some 345 patients completed a six-month follow up.
Medtronic’s prime investigator, William Abraham, MD, noted that the study reached its primary benefit goals, although those did not include increased survival.
Six months after the implant, doctors reported that 68% of those with the device improved at least one class vs. only 38% who improved without the device.
There was also “marked” improvement, Abraham said, with how far patients with the device could walk during a six-minute span. Those patients with the device also reported twice the quality-of-life increase as the other group, and spent 81% fewer days in the hospital over the six-month follow-up period.
Nevertheless, the device is not risk-free. Indeed, as a condition for approval, the advisory panel voted to require that one-year data be collected to track possible deaths related to its use.
During the Medtronic study, four coronary sinus dissections and two other adverse events occurred. All the events were resolved, however, without patients dying. After the implant, 48 events in 38 patients were reported related to complications with the implant’s electronic leads. And other system-related complications were reported in another 55 patients.
The FDA often follows the lead of its advisory panels but is not bound by their recommendations.
Earlier in the day, the expert panel voted 6-2 against recommending approval for another implanted device for the treatment of heart failure. Guidant’s cardiac resynchronization therapy device includes a cardiac defibrillator and is aimed at preventing pump failure and sudden cardiac death in patients with the condition.
But NIH cardiology expert Michael Domanski, MD, said that Guidant’s clinical study of the device showed no evidence of its benefit.
The trial failed to significantly slow patients’ progression to heart failure. Meanwhile, patients on the device showed similar improvements in exercise tolerance, peak oxygen flow, and quality of life as a comparison group that didn’t get the implant.
In addition, the device directly caused at least two deaths.