MedWire News: Implantable cardioverter-defibrillators to not reduce quality of life in patients with heart failure, US study results show.

Writing in the New England Journal of Medicine, Dr Daniel Mark, from Duke University Medical Center in Durham, North Carolina, and colleagues explain that studies have shown that implantable cardioverter-defibrillators can significantly improve the life expectancy of some people with heart failure by delivering small 'shocks' of electricity to correct heart rhythm abnormalities.

However, they add: "Whether this increased longevity is accompanied by deterioration in the quality of life is unclear."

To investigate, the team studied 2521 patients with heart failure who were all receiving 'state-of-the-art' medical therapy for their condition.

In addition to medical treatment, one-third of the patients were assigned to receive an implantable cardioverter-defibrillator, a second group was assigned to receive an abnormal heart rhythm-correction drug and a third group took a dummy medication.

All the participants were interviewed four times over a 30-month period to assess the severity of their condition, their physical and social activity levels, psychological well-being and ability to perform routine daily tasks.

The researchers found that, overall, patients in all groups enjoyed a relatively good quality of life despite having significant heart failure. Indeed, many reported experiencing a modest number of days when they had to stay in bed or felt that they did not have enough energy, 86% said they were able to drive a car, 92% said they could manage their finances independently and 27% said they were still employed outside the home.

Patients with implantable cardioverter-defibrillators actually had somewhat better quality of life scores at 3 and 12 months than the other patients. However, this difference diminished over time and disappeared at 30 months.

Commenting on the findings, Dr Mark said: "Medical intervention almost always brings about unintended consequences. We began examining these patients when implantable cardioverter-defibrillators were still relatively new, and until now, we were not entirely sure that in using a device to prolong life we weren't causing additional problems in the process.

"We are now happy to report that we found no evidence of that in this large trial. implantable cardioverter-defibrillator users, on the whole, appear satisfied with the benefits and the consequences of defibrillator therapy," he concluded.