Apr 19, 2001
Study Shows Value of Implantable Defibrillation Therapy vs. Drugs

Guidant to Apply for New Indication Based on Study Results

Indianapolis, IN, and St. Paul, MN - Results of the first clinical study to demonstrate that implantable cardioverter defibrillators (ICDs) are better than drugs in saving lives of people who have no structural heart disease and a normal ejection fraction were presented April 10 at the 13th Annual Michel Mirowski Sudden Cardiac Death Symposium in Baltimore. The Defibrillator vs. Beta-blockers for Unexplained Death in Thailand (DEBUT) study was supported by a grant from Guidant Corporation, (NYSE and PCX:GDT), a global leader in cardiac and vascular technology, and from the Cardiac Rhythm Management Research Foundation.

Principal investigator Koonlawee Nademanee, M.D., director of the Pacific Rim Electrophysiology Research Institute and director of electrophysiology at the Tommy Lasorda Heart Institute, Inglewood, Calif., studied Thai men who were at high risk of a hereditary condition called Sudden Unexplained Death Syndrome (SUDS). This arrhythmic condition, identifiable by a distinctive ECG pattern, kills Southeast Asians in their 20s, 30s and 40s suddenly at night. Sufferers have normal cardiac anatomy.

The Thai investigator group randomized 61 subjects who had survived a SUDS episode or had the identifiable ECG pattern to either beta-blocker or to the implantation of a Guidant VENTAK® single-chamber ICD in a 1:1 ratio. Eleven patients, or 18 percent, experienced a Sudden Cardiac Death (SCD) event. Four people in the beta-blocker arm died as a result, while the ICD saved the lives of the remaining seven patients in the ICD arm of the trial, who had experienced multiple episodes of life-threatening ventricular arrhythmias. There were no deaths in the defibrillator arm of the study.

Because of the number of deaths in the beta-blocker group, the Data Safety Monitoring Board stopped the trial in December 2000. Guidant will apply to the U.S. Food and Drug Administration (FDA) for a new indication for ICDs for the population studied.

"Although beta-blockers appeared to be effective in reducing the number of recurrent VF episodes in the DEBUT patient population, the drugs did not provide full protection against death from VF in this study," said Dr. Nademanee.

He believes the implications of the DEBUT study go beyond the group of men studied in Thailand. "Because SUDS is a genetic phenomenon, Southeast Asian family members could carry the same risk as the men studied in the DEBUT trial," Dr. Nademanee said. "Southeast Asian people who have emigrated to the U.S. and other countries may not know their genetic risk because they are separated from their family members. Persons in this population who are concerned should consult a physician. A simple ECG test is the first step in identifying persons who may carry this hereditary condition."

Guidant officials are looking forward to publication of the study. "The DEBUT trial builds on the results of other landmark studies, such as MADIT, AVID, and MUSTT, that demonstrate the lifesaving value of implantable defibrillation therapy," said Fred McCoy, president, cardiac rhythm management, Guidant Corporation. "We at Guidant continue to help sponsor groundbreaking scientific studies to help physicians identify patients who are at high risk of sudden cardiac death. Our confidence in implantable defibrillation therapy as a medical solution increases with each positive study outcome."

A global leader in the medical technology industry, Guidant Corporation provides innovative, minimally invasive and cost-effective products and services for the treatment of cardiovascular and vascular disease.