Results from the study demonstrated that overdrive pacing with the AF Suppression(tm) algorithm decreases symptomatic AF burden significantly in the group of patients with sick sinus syndrome, paroxysmal AF and standard pacemaker indications.
Significant findings from the ADOPT-A trial include a 25 percent reduction in symptomatic AF burden in patients in the AF Suppression(tm) algorithm "ON" group vs. the AF Suppression(tm) algorithm "OFF" group, and there was a consistent and decreasing AF burden trend observed over time (p<0.005).
"The AF Suppression(tm) algorithm offers a device-based approach to suppressing AF through 'intelligent' overdrive stimulation," noted Eric S. Fain, M.D., Senior Vice President, Development and Clinical/Regulatory Affairs for St. Jude Medical's Cardiac Rhythm Management business. "Many previous atrial overdrive methods were based on fixed overdrive pacing, which can be uncomfortable for patients at rest or sleeping. In addition, fixed overdrive pacing can't result in the high percentage of atrial pacing that's possible with AF Suppression(tm)."
"This algorithm tailors the atrial rate to pace just above the patient's intrinsic rate to allow for activity and circadian variation," said Michael J. Coyle, President of St. Jude Medical's Cardiac Rhythm Management business. "The AF Suppression(tm) feature has been available to our physician customers, who report that it's effective, well tolerated and easy to use. We're confident that publication of the ADOPT-A trial results, in addition to the presentation of the OASES trial data at NASPE's Late-Breaking Clinical Trials session in May 2003, will increase awareness of the clinical utility of this algorithm in the medical community and bring this benefit to more patients."
Decreasing AF burden has been shown to correlate favorably to increasing a patient's quality of life.
While it has been widely accepted that standard dual-chamber (DDDR) pacing can reduce the occurrence of AF as compared to single chamber (VVIR) pacing, the completed ADOPT-A study demonstrates that AF Suppression(tm) pacing provides an increased reduction in symptomatic AF as compared to standard DDDR pacing. The ability to provide such therapy may be especially important for pacemaker patients. It has been shown that over 43 percent of patients implanted with a pacemaker for sick sinus syndrome or AV block (common pacing indications) will develop some sort of atrial arrhythmia within the first year of implant.*
The ADOPT-A study was a multi-center, randomized, controlled, single-blind study designed to evaluate the use of the breakthrough AF Suppression(tm) algorithm to suppress symptomatic AF episodes in patients with bradycardia and a documented history of PAF. Initial results of ADOPT-A were presented at NASPE in May 2001.
Patients enrolled in the study were randomized into two groups: one with the AF Suppression(tm) algorithm "ON" and DDDR pacing at 60 ppm; the other with the AF Suppression(tm) algorithm(tm) "OFF" and DDDR pacing at 60 ppm. Patients were followed for six months post implant. The trial, which spanned two-and-a-half years, featured approximately 150 patients in each group. Patients underwent a standard dual-chamber pacemaker implant, with leads positioned in the right atrium and right ventricle. No specific right atrial lead implant site was required.
Atrial fibrillation, the most common chronic arrhythmia, affects an estimated 2.3 million people. In the United States, AF presents an immense medical and financial burden, with annual healthcare costs of $1 billion.
Characterized by rapid, uncoordinated and uncontrolled contractions of the atria (the upper chambers of the heart), AF keeps the heart from pumping blood efficiently. AF is a common risk factor for - and cause of - stroke. AF also markedly diminishes quality of life, and exacerbates heart failure (HF). In fact, an estimated 25 percent of HF patients also have AF. Until recently, approaches to AF treatment centered primarily on pharmacological therapy. Now, however, device therapies such as the AF Suppression(tm) algorithm are proving effective.
The algorithm has been available in the United States since the approval of the Integrity® AFx Model 5346 pacemaker in July 2001, and is now featured in several St. Jude Medical products including the new Epic(tm)+ DR implantable cardioverter defibrillator (ICD) and the Identity® pacemaker families.
Any statements made regarding St. Jude Medical's anticipated future product launches, regulatory approvals, revenues, earnings, market shares, and potential clinical success are forward-looking statements which are subject to risks and uncertainties, such as those described in the Financial Section of the Company's Annual Report to Shareholders for the fiscal year ended December 31, 2002 (see pages 6-8). Actual results may differ materially from anticipated results.
St. Jude Medical, Inc. (www.sjm.com) is dedicated to the design, manufacture and distribution of innovative medical devices of the highest quality, offering physicians, patients and payers unmatched clinical performance and demonstrated economic value.
*Garrigue S. et. al. Arch Mal Coeur Vaiss 1996; 89 (7): 87-88.
Journal
Journal of the American College of Cardiology