Medtronic ablation therapy treats heart rhythm disorder better

Developed by a U.S. based firm Medtronic Inc., the technique which freezes the heart tissue with a balloon catheter to treat the heart rhythm disorder was found to be 10 times better than the drug therapy.

Details of the study
To determine the efficacy of the ablation therapy, a research team led by Douglas Packer of the Mayo Clinic in Rochester, Minnesota, carried out a study on 254 patients with paroxysmal atrial fibrillation.

Paroxysmal atrial fibrillation is a condition marked by irregular episodes of abnormal heart rhythm that causes palpitations in the upper chambers of the heart.

For the study, the patients were randomly divided into two groups. One group was administered the ablation therapy and the other was assigned the drug therapy. All the patients were then followed up for a year.

In the ablation system, which lasts for at least three hours, doctors insert a balloon catheter into a vein in the heart's left auricle.

The balloon is then filled with a liquid which then kills the abnormal heart tissue.

Results of the study
On analysis, the CryoAblation procedure was found to be as safe as the drugs but far more effective in treating the heart rhythm disorder after a year of surgical procedure.

Nearly 70 percent of those who were put on the ablation system remained free of the condition a year after the surgery compared to just seven percent of those who received the drug therapy.

Six percent of patients treated with drug therapy experienced a recurrence of the condition and were hospitalized, compared to less than one percent of patients treated by cryoablation.

"This is the best data we have at this point in support of CryoAblation (to treat atrial fibrillation)," said Dr. Douglas Packer, the lead investigator of the study.

The study was presented at the 59th annual conference of the American College of Cardiology in Atlanta, Georgia.

Minor side effects reported
Overall, only three percent of the patients in the CryoAblation group experienced narrowing of the pulmonary vein, a serious medical condition.

Some 11 percent patients treated by CryoAblation also reported damage to the nerve that controls the diaphragm, though these side effects weren’t alarming as most of them were resolved within the study period.

Further, 97 percent of the patients in the CryoAblation didn’t suffer a heart attack or a stroke compared with 92 percent in the drug therapy group.

The findings of the study are indeed 'significant' but larger trials are needed to confirm them as the study is still in its preliminary stage, the researchers said.