Innovative new treatment for moderate to severe heart failure

Sep 26 2005

Cardiologists at Beth Israel Medical Center are currently enrolling patients in an investigational study that is looking at the safety and efficacy of an innovative new treatment for moderate to severe heart failure, in which a unique pacemaker-like device helps strengthen the heart's pumping power.

The FIX-HF-5 (Fix Heart Failure 5) study involves a pulse generator, the Optimizer(TM) System, that delivers electrical signals to the heart muscle in the midst of its pumping action, "fooling" it into producing more intracellular calcium and thus increasing the heart's ability to pump and contract. The study is sponsored by Impulse Dynamics (USA) Inc., the manufacturer of the Optimizer System.

More than 5 million Americans are living with heart failure, a debilitating condition in which the heart is too weak to pump blood at its full ability, leading to a continuing decline in a patient's health and an increased frequency of hospitalization and premature death. Chronic heart failure is implicated in more than 300,000 deaths in North America each year and is the leading cause of hospital admissions for patients over 65. A person aged 40 or older has a one-in-five chance of developing chronic heart failure, according to a recent study in Circulation: Journal of the American Heart Association, and the average five-year survival rate for all patients with heart failure is currently only about 50 percent.

Similar to a pacemaker, the Optimizer System consists of a programmable implantable pulse generator, a portable programmer and two right ventricular leads. Whereas pacemakers focus on modulating the heart's rhythm, the Optimizer System is based on a new technology known as Cardiac Contractility Modulation (CCM). Unlike with pacemaker signals, which are delivered during a period of the cardiac cycle when a new beat can be initiated, the CCM signals are "non-excitatory," meaning they are delivered during the absolute refractory period and therefore cannot initiate a new contraction. Instead, the CCM delivers impulses to the heart muscle during a moment in the heartbeat known as the absolute refractory period. The result, believe investigators, is that CCM signals trigger a response in the calcium that is cycling within the heart cells, in a manner that improves the strength of the heart muscle's contraction, and without adding to its overall workload.

"The potential to improve the heart's pumping ability while decreasing its workload would present a significant development in treating patients with Class III or Class IV heart failure," said Jill Kalman, MD, director of the heart failure program at Beth Israel Medical Center and lead investigator of the FIX-HF-5 trial at the hospital. "If proven to be safe and effective, the Optimizer system would be a valuable tool in treating heart failure patients."

Patients wishing to enroll in the FIX-HF-5 trial must have previously received standard heart failure therapy for at least 90 days including use of stable doses of diuretic, ACE-I and beta-blocker for 30 days, can complete exercise tolerance tests, and have an ejection fraction less than or equal to 35%. Eligible patients may undergo simultaneous implant of a pacemaker or an implantable cardiac defibrillator at the time of the implant of the Optimizer(TM) System or may already have such devices.

Patients not eligible for participation in FIX-HF-5, include those who have correctable cause of heart failure, chronic atrial fibrillation, clinically significant angina pectoris or experienced a heart attack within the past three months. Additional patients not eligible for FIX-HF-5 include those who are currently receiving biventricular (BiV) pacing, are indicated for BiV or whose exercise tolerance is limited by non-heart failure conditions.

FIX-HF-5 is targeting to enroll approximately 400 New York Heart Association (NYHA) Class III or Class IV heart failure patients at up to 50 sites across the United States.