Implantable devices have been used for decades to treat heart disease. The first pacemaker was implanted over 40 years ago, and implantable defibrillators were first used in the early 1980s. But the last few years have witnessed a surge in both the types of devices being tested for heart-failure treatment, and in the optimism of experts about their usefulness.
The symptoms of heart failure can be related to the pooling of fluid in the body or can be secondary to decreased blood flow to the body. Some people with heart failure don't experience symptoms, but here are some of the more common signs:
Shortness of breath with exercise or difficulty breathing at rest or when lying down
Swollen legs, ankles, or abdomen
Dry, hacking cough, or wheezing
Other symptoms may include:
Fatigue, palpitations, or pain during normal activities
"A lot of the big advances that we've had in treating heart failure in the last few years has been with devices," says Marvin A. Konstam, MD, chief of cardiology and director of cardiovascular development at Tufts-New England Medical Center. "It's an exciting time."
Eric Rose, MD, agrees. "Things are dramatically different in the last five years," says Rose, department of surgery chairman at the Columbia University College of Physicians and Surgeons. "For instance, the dream of using machines for long-term supportive patients with end-stage heart failure is now a reality."
But Rose, who led a study of one such implant used in heart-failure treatment -- the left ventricular assist device -- is temperate in his enthusiasm. "It's a reality, but I should say that it's a reality with mediocre outcomes at this point," he tells WebMD. "That's still an improvement over God-awful, which is what the prognosis was before."
While advances in devices are impressive, all experts agree that we are only in the early stages of their development. It remains to be seen how widely and how quickly these life-saving implants will become available for routine heart-failure treatment.
Given that heart failure is not a specific disease in itself, but rather a condition that results from other illnesses, different approaches have been developed to treat the condition. Some stem from the familiar pacemaker, others from devices designed as a stopgap before heart transplant.
Implantable Cardioverter Defibrillators (ICDs)
An ICD is used for heart-failure treatment when the person is considered to be a high risk of dying from an abnormal heart rhythm -- called sudden cardiac death. It is a small device that is implanted in the chest and continually monitors the heart's rhythm. If the ICD senses a dangerous abnormal heart rhythm, it delivers an internal electric shock to the heart -- the equivalent of being shocked with paddles outside the body -- that hopefully restores a normal heart rhythm.
Given that sudden cardiac death from fatal, abnormal heart rhythms causes about 50% of all heart-related deaths, ICDs have enormous potential. One recent study found that ICDs reduced sudden cardiac death in people at risk for it -- such as those with a previous heart attack or heart failure -- by more than 50%.
Of course, there is a potential disadvantage to having an ICD for heart-failure treatment: If the experience of being shocked by a box in your chest doesn't sound pleasant, you're right. While some report minor discomfort, others find it extremely painful and anxiety-provoking. This is particularly troublesome in people who have frequent episodes of this potentially fatal abnormal heart rhythm.
"There have been some studies [that] showed that after getting two shocks, people's anxiety went sky high," says Susan J. Bennett, DNS, RN, a professor in the Indiana University nursing school and a specialist in treating the condition. "But the other thing that happens is that some patients who get shocked are grateful because they know the device is working and they know that it saved their lives."
ICDs can be implanted alone, but they are also combined with other devices, such as cardiac resynchronization therapy, for heart failure treatment.