Arthur J Moss, professor of medicine, University of Rochester Medical Center, USA, presented positive results from the MADIT-RIT (Multicentre automatic defibrillator implantation trial-reduce inappropriate therapy) clinical trial at the American Heart Association Scientific Sessions (Los Angeles, USA, 3–7 November). Data demonstrated that improved programming of dual-chamber implantable cardioverter defibrillator (ICD) or cardiac resynchronisation therapy defibrillator (CRT-D) heart devices can reduce inappropriate therapy and risk of death.
MADIT-RIT, sponsored by Boston Scientific, is a prospective randomised three-arm trial comparing conventional programming with two alternative settings: a high-rate therapy arm and a duration-delay arm. Both shock therapy and anti-tachycardia pacing (ATP) therapy were evaluated in the trial. The study was designed to determine if alternate programming could reduce the occurrence of inappropriate therapy in primary prevention patients. The full MADIT-RIT results have been published in the New England Journal of Medicine.
MADIT-RIT evaluated 1,500 primary prevention patients with an ICD or CRT-D at 98 centres in 15 countries, including the USA, Europe, Canada, Israel and Japan.
When compared to conventional programming, significant reduction of inappropriate therapy was seen in both the high-rate and duration-delay therapy arms [79 and 76%, respectively (p<0.001 in both arms)].
In the high-rate therapy arm, there was a significant 55% reduction of the risk of death (p=0.01) compared to conventional programming. While not statistically significant, the risk of mortality was reduced in the duration-delay therapy arm by 44% (p=0.06).
“I have been the principal investigator of a series of MADIT trials that have improved survival of high-risk heart patients during the past 20 years,” said Moss, who is the principal investigator or MADIT-RIT. “I am pleased to report on our latest 1,500-patient MADIT study in which we have significantly improved the effectiveness of ICDs by reducing inappropriate electrical stimulation of the heart by up to nearly 80% while further increasing patient survival by up to 55%. These life-saving findings from our current study add an important new chapter in the evolution of the ICD to improve the treatment of patients with advanced heart disease.”
“MADIT-RIT shows that improved programming can dramatically reduce inappropriate therapies and increase survival when compared to conventional device programming,” said Kenneth Stein, chief medical officer of the Cardiac Rhythm Management Group at Boston Scientific. “This will have immediate clinical significance for physicians who implant and manage these devices. While previous studies have shown that ICDs are very effective in preventing sudden cardiac death, this study demonstrates that substantially more lives can be saved and many unnecessary and inappropriate therapies can be avoided with improved device programming.”