St. Jude Medical Announces CRT Patients Showed Significant Improvement in the RHYTHM ICD Study.

Business Editors/Health/Medical Writers

ST. PAUL, Minn.--(BUSINESS WIRE)--March 9, 2004

All Primary Endpoints were Achieved

St. Jude Medical, Inc. (NYSE:STJ) announced today that data from its RHYTHM (Resynchronization HemodYnamic Treatment for Heart Failure Management) ICD clinical trial showed a statistically significant improvement in peak VO2 and exercise duration for patients treated with cardiac resynchronization therapy (CRT). All prospectively defined primary safety and efficacy endpoints of the study were successfully met. The announcement was made today in conjunction with the American College of Cardiology's 2004 Scientific Session in New Orleans, Louisiana.

"The Epic(TM) HF ICD evaluated in this study effectively combines pacemaker therapy, defibrillation therapy and left-heart stimulation to treat the complexities of heart failure," said Kyong T. Turk, M.D., of the Nebraska Heart Institute, Lincoln, Nebraska, who enrolled the most patients in the RHYTHM clinical study. "These multiple sophisticated therapies in one compact, easy to implant device give me significant flexibility to optimize patient care."

The primary efficacy endpoint of the RHYTHM ICD study was improvement in cardiac function as measured by patient peak VO2 during cardiopulmonary exercise testing. The clinical trial was sized based on an expectation that the CRT arm of the study would show a 1.6 ml/kg/min improvement in peak VO2 compared with the control group, which did not have the CRT feature activated. The actual observed improvement level for CRT compared to control was 1.93 ml/kg/min, which was statistically significant (p=0.001). Secondary endpoints concerning NYHA class and Quality of Life were also statistically significantly improved with CRT (p=0.048 and p=0.009, respectively), with the six minute walk test demonstrating a strong trend toward significance (p=0.07). The study evaluated resynchronization effectiveness, defibrillation system efficacy, defibrillation system safety and left ventricle lead performance.

"This is a significant prospective, randomized study, which adds to the growing body of evidence supporting the therapeutic effectiveness of cardiac resynchronization therapy as an adjunct to optimal medical therapy for heart failure patients," added Eric S. Fain, M.D., Senior Vice President, Development and Clinical/Regulatory Affairs for St. Jude Medical's Cardiac Rhythm Management business. "The RHYTHM study has a rigorous protocol with more stringent inclusion/exclusion criteria than previous studies, so all of the participating RHYTHM ICD investigators should be congratulated on achieving this important milestone."

Patients enrolled in the RHYTHM ICD study have an approved indication for an ICD; symptomatic, advanced heart failure (NYHA Class III/IV) not due to reversible causes, for at least six months, despite receiving optimal pharmacological therapy for a minimum of 90 days; an ejection fraction of less than or equal to 35% (volume of blood pumped compared to volume filled), and a prolonged QRS duration (ventricular activity shown in an electrocardiogram).

The RHYTHM study evaluated the St. Jude Medical Epic(TM) HF model V-338 implantable cardioverter defibrillator (ICD), which is used to treat heart failure patients who are also at risk of dangerously fast heart rhythms (ventricular tachyarrhythmias). The Epic(TM) HF ICD offers negative AV/PV hysteresis with search capability designed to ensure a high percentage of biventricular pacing. It's the world's smallest high-voltage cardiac resynchronization device, designed to make implantation easier while improving patient comfort and cosmetic appearance. The device delivers 30 joules of energy in a physiologic-shaped 36-cc ICD.

The device was paired with either the Aescula(TM) model 1055K or QuickSite(TM) model 1056K left heart lead. During the separate QuickSite phase of the RHYTHM ICD Study, the implant success rate of the QuickSite lead was 94.4%. All prospectively defined endpoints of the QuickSite phase of the study were met.

Data from the RHYTHM study is the basis for submission to the U.S. Food and Drug Administration (FDA) for approval of the devices used in the study. St. Jude Medical reaffirms its previous guidance that it expects FDA approval of the studied devices by the May 2004 NASPE/Heart Rhythm Society meeting.

Heart failure is one of the most widespread cardiac afflictions, affecting approximately five million people in the United States. About 550,000 new patients are diagnosed with heart failure each year. The majority die within five years of diagnosis.

Any statements made regarding the Company's anticipated future product launches, 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 4-6). 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.