Medical Device Daily

Medtronic (Minneapolis) said it intends to seek FDA approval for the use of cardiac resynchronization therapy (CRT) in certain mildly symptomatic heart failure patients. According to the company, CRT is a "proven life-saving therapy" for some patients with advanced heart failure (New York Heart Association Class III, IV), however it is not currently approved for use in earlier stage, or mildly symptomatic patients.

"Overall we have invested a great amount in looking at who our devices work best for and there is this initial data that we'll be submitting as part of the process that does show this therapy, CRT, will work in different patients, and by different patients we mean people who are in earlier stage heart failure," Kyra Schmitt, a Medtronic spokesperson, told Medical Device Daily.

This initial data includes studies such as the REVERSE trial, as well as other heart failure research the company has done, Schmitt said.

"Results from large-scale studies like REVERSE suggest benefits with CRT for patients with mild heart failure," said David Steinhaus, MD, medical director of the Cardiac Rhythm Disease Management business at Medtronic. "For some heart failure patients, CRT appears to slow the progression of the disease, and delay time to first heart failure hospitalization or death – which can have a great impact to the healthcare system."

In April Medtronic reported data from its REVERSE (Resycnhronoization Reverse Remodeling in Systolic Left Ventricular Dysfunction) trial that showed the benefits of CRT in patients with mild heart failure. The study results revealed a 62% reduction in the risk of first heart failure hospitalization or death (Medical Device Daily, April 1, 2009).

In REVERSE, CRT used in combination with optimal medical therapy, including beta blockers and ACE inhibitors or aldosterone-receptor blockers, led to a statistically significant improvement in heart failure clinical composite score at 24 months, a standard measurement that includes several clinical measures of heart failure status, Medtronic noted. The REVERSE trial began enrolling patients in 2004 and is the first large-scale, global, randomized, double-blind study to suggest the benefits of CRT in mild HF patients or asymptomatic patients who previously had HF symptoms, according to the company.

"We look forward to continued discussions with the FDA on the role CRT can potentially play in heart failure treatment regimens for early stage heart failure patients," Steinhaus said. "At Medtronic, our goal is to provide innovative solutions to the most challenging healthcare problems, and we are hopeful that earlier intervention with CRT will help both physicians and patients to better address this serious and often debilitating condition."

Medtronic said its decision to pursue this approval precedes anticipated results from the fully enrolled Canadian RAFT (Resynchronization / Defibrillation in Ambulatory Heart Failure Trial) study, which is evaluating the impact of CRT on all-cause mortality and heart failure hospitalization in NYHA Class II patients, as well as other industry trials that continue to assess CRT for mildly symptomatic heart failure patients.

"These are patients who have less symptoms but that doesn't necessarily mean that they don't require treatment," Schmitt said. "It's about hopefully getting to them earlier, before their disease progresses further."

Seeking approval for this indication represents Medtronic's "overall approach to make sure, again, we're getting the therapy to the patients who will benefit from it most," Schmitt said.

Other heart failure research Medtronic has done includes:

• The Cardiac Resynchronization in Heart Failure (CARE-HF). CARE-HF was initiated in 2001, evaluated NYHA Class III, IV patients for 18 months and demonstrated CRT improves symptoms and reduces complications and risk of death, Medtronic said.

• MIRACLE / MIRACLE ICD (Multicenter InSync / ICD Randomized Clinical Evaluation) studies. These studies, initiated in 1998 and 1999, respectively, evaluated NYHA Class III, IV patients for six months and demonstrated significant improvements in quality of life and cardiac function, according to the company.

Medtronic heart failure research studies currently under way include:

• BLOCK HF (Biventricular Versus Right Ventricular Pacing in Heart Failure Patients With Atrioventricular Block) trial. BLOCK HF was initiated in 2003, is determining the value of CRT in patients with AV block and at risk of developing worsening heart failure at trial sites in the U.S. and Canada.

• IMPROVE HF (Improve the Use of Evidence-Based Heart Failure Therapies in the Outpatient Setting). IMPROVE HF is designed to quantify and improve quality of care for heart failure patients by promoting the use of evidence-based, guideline-recommended therapies, Medtronic said.

• OptiVol Care Pathway, a study assessing whether more frequent (monthly vs. quarterly) review of OptiVol Fluid Status Monitoring patient data results in earlier clinical intervention.