New heart device raises risk of fatal blood infection

Patients with pacemakers and other implanted heart devices are at risk of a life-threatening bacterial blood infection, new study findings suggest. In many patients who developed staphylococcus aureus bacteremia (staph infection) and had a cardiac device implanted, the device was the source of the infection. Often, these patients had no obvious signs of infection, even after undergoing echocardiography, a procedure that allows doctors to view the heart, according to reports from the Journal of the American Heart Association.

The authors suggest that based on the study findings, doctors treating patients who develop staph infections and have heart devices, should suspect that the device itself has become infected and consider surgically removing it, rather than treating the blood infection with antibiotics. In the study, conducted by researchers at Duke University, Durham, North Carolina, patients who did not have the device removed were more likely to die than patients who underwent the surgery to have their device taken out. “In patients with staphylococcus aureus bacteremia and an implanted cardiac device, the likelihood that the device is infected is high, especially in the first year after the device is placed,” Dr Anna Lisa Chamis, the study’s lead author, told Reuters Health. “Physicians must be more vigilant in seeking out device infection with echocardiography and blood cultures, even if the physical examination does not suggest cardiac device infection.” The Duke researchers found that 15 of 33 patients with an implanted heart device developed a staph infection in the blood within 6 years. Nine of these patients developed the infection within their first year of living with the device. In three of the nine patients, the infection originated in another part of the body and spread to the heart device, while six cases were caused by the device itself, the report indicates. In most cases, there were no obvious signs that the device was infected, such as redness or inflammation in the tissues covering the device, Chamis and colleagues report. The infections were diagnosed on the basis of blood tests. According to the researchers, cardiac device infection of one kind or another occurs in up to 20 per cent of patients with a permanent pacemaker—a small battery-operated device that helps the heart beat regularly, and in up to 1.3 per cent of those with an implantable cardioverter-defibrillators, which shocks the heart into a normal rhythm.

(Source:Reuters Health)