St. Jude Medical Announces Initiation of ASSIST Clinical Trial.

Business Editors/Health/Medical Writers

ST. PAUL, Minn.--(BUSINESS WIRE)--Aug. 21, 2003

St. Jude Medical Inc. (NYSE:STJ) announced today the initiation and first patient enrollment in the ASSIST (Atrial Tachyarrhythmia Suppression Strategy in ICD Subjects Trial) clinical study. The purpose of the ASSIST study is to evaluate if atrial fibrillation (AF) suppression pacing in dual-chamber ICD patients will reduce atrial arrhythmia burden and the frequency of inappropriate VT/VF therapy in patients with a history of paroxysmal atrial fibrillation. The patient received a St. Jude Medical Epic(TM)+ DR implantable cardioverter defibrillator (ICD), the world's only ICD with clinically proven AF Suppression(TM) technology.

"By including AF Suppression pacing in this small dual-chamber ICD, we are able to provide patients with two important therapies without compromising overall performance," said Demos Iskos, M.D., who performed the first implant in the ASSIST study using an Epic(TM)+ DR ICD (Model V-236) at McKay-Dee Hospital Medical Center in Ogden, Utah. The procedure went as expected and the patient, a 65-year-old male, is doing well.

"ASSIST is the first study to evaluate the impact of St. Jude Medical's AF Suppression(TM) algorithm with an ICD patient population," said Dr. Roy Sauberman, principal investigator of the ASSIST clinical trial at Newark Beth Israel Medical Center in Newark, New Jersey. "This is a significant study for physicians who treat patients with both atrial and ventricular tachyarrhythmias, because AF can affect the functioning of an ICD as well as a patient's overall quality of life."

"Our AF Suppression(TM) technology has already been proven clinically effective in reducing AF burden," said Michael J. Coyle, President of St. Jude Medical's Cardiac Rhythm Management business. "We hope to demonstrate that this technology can also reduce the incidence of inappropriate therapy delivered to patients suffering from ventricular tachyarrhythmias, bradyarrhythmias and atrial tachyarrhythmias."

The ASSIST trial is a randomized study being conducted at 40 centers across the country. Patients will be divided into AF Suppression algorithm "ON" and AF Suppression algorithm "OFF" groups. The trial is estimated to last two years to achieve the study population.

To be included in the study, patients must have a standard indication for a dual chamber ICD, be in sinus rhythm (or cardioverted into sinus rhythm) at time of ICD implant, and have a recent episode (within six months) of paroxysmal AF. A stable anti-arrhythmic medication regimen will be maintained during the clinical trial. Patients with chronic AF (unable to cardiovert into sinus rhythm) are not included in the study.

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.