Pacemakers for heart failure

Many people with heart failure have problems with the electrical function of their hearts. As a result, the heart's beating pattern may not be normal. This can reduce the pumping efficiency of the heart.

A pacemaker is an electrical device that is implanted under the skin of your chest wall. The pacemaker's wires are passed through a vein into the chambers of your heart. It sends out small electrical pulses that stimulate your heart to beat in a synchronized pattern.

Although pacemakers have been used for many years to treat slow heart rate problems and other heart rhythm abnormalities, they have only recently been studied and approved for use in people with heart failure.

Biventricular pacing

A biventricular pacemaker synchronizes the rhythm of the heart's lower chambers (cardiac resynchronization) so that the chambers contract at the same time. Biventricular pacemakers are used in people who have heart failure and problems with the heart's electrical system. In one large study, people with heart failure who received the biventricular pacemaker showed significant improvement, including increased capacity for exercise and decreased symptoms. The study suggests that cardiac resynchronization is helpful for people with moderate to severe heart failure who also have ventricular dyssynchrony, which is a lack of coordination of the ventricles.¹

Guidelines from the American Heart Association recommend that biventricular pacing may be a reasonable option for people with severe heart failure (class IV).² Further studies are ongoing to see whether this therapy might also benefit those with less severe heart failure.

Another new option is a device that combines an implantable cardioverter-defibrillator (ICD) with a biventricular pacemaker. This device offers a dual-chamber pacemaker with a defibrillator that can detect and stop life-threatening arrhythmias.

Studies have found that this combined device significantly reduced hospitalizations and death rates in people with advanced heart failure.³ Although these new devices show promise, some people did not benefit from them. However, researchers have steadily improved pacemaker technology and more improvements are expected.

Citations

1. Abraham WT, et al. (2002). Cardiac resynchronization in chronic heart failure. New England Journal of Medicine, 346(24): 1845–1858.

2. American College of Cardiology and American Heart Association (2002). ACC/AHA/NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices. Summary article. Report of the ACC/AHA Task Force on Practice Guidelines. Available online: http://circ.ahajournals.org/cgi/content/full/106/16/2145

3. Bristow MR, et al. (2004). Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. New England Journal of Medicine, 350(21): 2140–2150.