Implantable cardioverter-defibrillators, or ICDs, are small battery-powered devices that are designed to prevent sudden cardiac deaths from dangerous heart arrhythmias, including ventricular fibrillation and ventricular tachycardia. ICDs are designed to detect a heart arrhythmia and correct it by shocking the heart with electricity. In many patients, these devices can save lives. However, according to a study published in the Journal of the American Medical Association last week, many surgeons may be using ICDs unnecessarily and putting patients at risk.
Unlike a pacemaker, which sends small amounts of electricity to the heart to regulate the heartbeat, an ICD jolts the heart with larger amounts of electricity to defibrillate the heart. Guidelines have been established that establish criteria for which patients should receive an ICD and which patients should not. Clinical trials have shown that ICDs can benefit people with heart arrhythmias, but research also indicates that ICDs offer no benefit to people recovering from a heart attack, coronary artery bypass surgery, or heart failure.
The study looked at more than 100,000 patients using data from the National Cardiovascular Data Registry and found that more than 20 percent of patients who received an ICD did not fall within the recommended guidelines governing eligibility for receiving an ICD. Additionally, the study found that patients who fell outside of the eligibility guidelines for receiving ICD but received an ICD anyway had a significantly higher risk of experiencing complications or death from the procedure.
The authors of the study argue that the extra risk of medical complications and death is unacceptable when balanced with little evidence of any benefit to patients who fall outside of the eligibility guidelines for receiving an ICD.
Source: ABC News, “Implantable Cardioverter-Defibrillators Overused,” Courtney Hutchison, 1/4/2011