Study: 40 Percent Of Pacemakers Don't Help

Heart patients sometimes have pacemakers implanted in their chest to help keep their heart on a regular beat. But researchers at Case Western Reserve University School of Medicine says the procedure fails to help 40 percent of the patients who get them.

The new meta-analysis study looked at a large number of previous studies on the issue.

"These findings have significant clinical implications and impact tens of thousands of patients in the U.S.," said Ilke Sipahi, MD, Associate Director of Heart Failure and Transplantation at UH Case Medical Center and Assistant Professor at Case Western Reserve University School of Medicine. "We found that pacemaker patients with less severe electrical disturbance in their hearts did not receive any benefit whatsoever from these expensive and potentially risky implants.”

Given the evidence, Sipahi and colleagues say current guidelines should be changed.

Analysis of previous studies

The research team investigated the treatment method known as cardiac resynchronization therapy (CRT). This highly sophisticated treatment technique involves pacing both ventricles of the heart in an attempt to correct the impaired timing of the heart beat.

The study is a combined analysis of clinical trials of nearly 6,000 patients and examines whether the current criteria used by the medical community in selecting patients for the treatment are appropriate.

Treatment guidelines endorsed by various professional societies recommend these pacemakers for patients with heart failure symptoms due to weak heart muscles that have a specific abnormality on the electrocardiogram (EKG) known as QRS prolongation.

 Current treatment guidelines

Current treatment guidelines recommend that heart failure patients with QRS prolongation to greater than 0.12 seconds should get these devices. However, the new meta-analysis demonstrates that patients do not have a survival benefit or a reduction in hospitalizations from these pacemakers, unless their QRS is prolonged to greater than 0.15 seconds, a threshold much greater than the 0.12 second cutoff advocated in the treatment guidelines.

Approximately 40 percent of patients receiving these devices have a QRS prolongation in the range of 0.12 to 0.15 seconds and do not get any benefit from pacemaker therapy, according to the results of the new study.

Unnecessary procedures

"This study can have profound impact on minimizing unnecessary procedures" said Sipahi. "Revising the criteria for implantation of these devices will help avoid thousands of unnecessary implants and will also lead to cutting down on unwarranted costs."

The cost of an implanted pacemaker was $35,000 to $45,000 in 2007, according to Blue Cross, Blue Shield of Tennessee. The additional cost of the procedure with associated medical care varies greatly depending on the place that the person receives the pacemaker.

In 2005 Guidant recalled a number of its pacemakers after at least 69 of the devices failed, causing at least one death.