Nearly 5 million people in the United States have congestive heart failure. Each year, there are an estimated 400,000 new cases, and half of those diagnosed with the condition will be dead within five years, according to the National Heart, Lung, and Blood Institute.
Researchers continue to develop treatments for this condition, in which the heart cannot adequately pump blood around the body, causing fluid to seep into the lungs and hinder breathing. Two of these treatments--a drug injection and a new type of pacemaker--recently were approved by the FDA.
Natrecor (nesiritide) Injection, a synthetic version of a human hormone, works by dilating the veins and arteries so more blood can flow through them.
In a study of 489 people who needed to be hospitalized because of shortness of breath due to congestive heart failure, participants were treated with either Natrecor, intravenous nitroglycerin, or an inactive substance (placebo) for three hours. Those receiving Natrecor reported greater improvement in shortness of breath than those receiving a placebo.
Natrecor's major side effect is low blood pressure. The drug is made by Scios Inc., of Sunnyvale, Calif.
People with congestive heart failure who have not been completely helped by drug treatment and whose hearts' pumping chambers (ventricles) don't beat in synchronization may be candidates for a biventricular pacemaker. The InSync Biventricular Cardiac Pacing System is the first biventricular pacemaker approved for treating the symptoms of congestive heart failure.
The InSync system consists of a pulse generator implanted in the chest and connected to the heart chambers by three wires (leads) that deliver electronic impulses. The impulses stimulate the left and right ventricles to pump together, helping the blood to flow more efficiently. The InSync pacemaker differs from a standard pacemaker in that it has three leads instead of one or two.
In a study of the InSync system, physicians implanted the device in nearly 600 people with moderate to severe congestive heart failure. They switched the system "on" in half of the study participants, and "off" in the other half. After six months, the majority of people with the activated device showed improvement in either quality of life scores, distance they were able to walk, or heart failure classification. About one-third of the people with the pacemaker turned off showed improvement. The study showed no major safety issues with the device itself. However, implanting the device requires special training for the physician.
The InSync system is made by Medtronic Inc., of Minneapolis. The FDA is requiring Medtronic to conduct a post-market study of the device in 1,500 people followed over three years.