Last week Medtronic announced that the FDA has given the company expanded indication for its portfolio of cardiac resynchronization therapy with defibrillator (CRT-D) devices to now treat mildly symptomatic, NYHA Class II heart failure patients. We had a chance to speak with Dr. David Steinhaus, M.D., Vice President and General Manager, Heart Failure, and Medical Director for the Cardiac Rhythm Disease Management business at Medtronic.
Ronney Shantouf, M.D., Medgadget: Can you explain the major difference between cardiac resynchronization therapy with implantable cardioverter defibrillator (CRT-D) devices vs. implantable cardioverter defibrillator (ICD) devices in terms what is implanted into the patient?
Dr. David Steinhaus: Both ICDs and CRT-Ds are small stopwatch-sized devices inserted directly under the skin in the upper chest. ICDs deliver lifesaving shocks or painless pacing to stop life-threatening fast or irregular heartbeats. CRT-D devices also stimulate the heart’s lower chambers to pump at the same time, and are used to help treat heart failure.
A standard ICD is fitted like a normal pacemaker, with either one or two leads in the right side of the heart. A CRT-D has a third and separate lead, which is threaded through the venous system and placed on the left ventricle.
Medgadget: What is the mechanism by which CRT-D potentially improves symptoms, re-hospitalization, and mortality?
Dr. Steinhaus: Using tiny electrical impulses delivered to the heart muscle, CRT-D therapy resynchronizes the contraction of both ventricles, improving the heart’s pumping ability. The device also works as a defibrillator to terminate life-threatening ventricular arrhythmias.
NYHA Class II heart failure patients were previously indicated for an ICD, which protects them from sudden cardiac arrest (SCA), but doesn’t address their heart failure status. They can now benefit from CRT therapy, which has been proven (via REVERSE and RAFT) to reduce the time to first heart failure hospitalization, and a lower risk of death (above and beyond the benefits of an ICD). So essentially, CRT helps slow the progression of heart failure and improves heart function. This indication expansion enables us to treat these patients with CRT before their heart failure symptoms start seriously eroding their quality of life. As such, we view this expanded indication as having a significant benefit for heart failure patients.
Medgadget: Currently what companies have FDA approval for placing a CRT-D device in NYHA Class II heart failure patients (those with mild symptoms) who meet criteria?
Dr. Steinhaus: Boston Scientific is the only other company that has received FDA approval for its CRT-D devices to include certain mildly symptomatic heart failure patients. This approval was based on the MADIT CRT trial it sponsored.
In December 2011, an FDA advisory panel voted to recommend that indications (labeling) for Medtronic CRT-D devices also be expanded to include certain mildly symptomatic heart failure patients. The Panel based its decision on the strength of the REVERSE and RAFT clinical trials, which showed a significant reduction in mortality over more than 5 years (RAFT) as well as significant reduction in time to first heart failure hospitalization (both REVERSE and RAFT).
Medgadget: Do you think it’s possible the guidelines will be expanded to include NYHA Class I Heart Failure patients?
Dr. Steinhaus: Not at this time. No NYHA I patients were enrolled in RAFT and only 18 percent of REVERSE patients were NYHA I; MADIT CRT also only included a small number of Class I patients. The medical societies typically rely on a multiple trials, with significant numbers of treated patients, in order to revise guidelines. It’s unlikely based on the small numbers of NYHA Class I patients in these trials that the guidelines would be adjusted to include them as candidates for CRT.
Medgadget: How does the expansion of implanting ICDs to now CRT-D devices in NYHA Class II heart failure patients affect health care costs?
Dr. Steinhaus: Cost-effectiveness data from the RAFT trial, a landmark clinical trial that served (along with REVERSE) as the basis for this approval, will be presented at the Heart Rhythm Society congress in Boston next month. Additionally, data has previously been presented reinforcing the cost-effectiveness of CRT based on the Medtronic-supported REVERSE and CARE-HF trials.
Medgadget: Where do you see the future technology headed for chronic heart failure patients and the specific role devices will play?
Dr. Steinhaus: Heart failure is a complex disease affecting millions of patients and consuming large health care resources. Heart failure is also responsible for significant mortality and decreased quality of life. Future technologies may include device therapy that modulates the autonomic nervous system—a key element in heart failure progression. Devices may also improve management of these patients by improved monitoring of important physiologic parameters. Ultimately sensors may be combined with drug delivery or other device therapy to create closed loop systems.