Miracle Study Results Released at ACC.Business Editors & Health/Medical Writers NOTE: PHOTOS, VIDEO AND BACKGROUND INFORMATION--relating to this story will be available for journalists to download beginning today at www.newstream.com. ORLANDO--(BUSINESS WIRE)--March 20, 2001 First large-scale study of cardiac resynchronization therapy in advanced heart failure patients; Study shows that therapy improves exercise capacity and quality of life Cardiologists meeting here today heard results of a landmark clinical trial showing that heart failure patients receiving a breakthrough new therapy to augment their standard medications exhibited marked improvement in exercise capacity and quality of life. Presenters at the 50th annual Scientific Sessions of the American College of Cardiology The American College of Cardiology (ACC) is a nonprofit medical association established in 1949 to educate, research and influence health care public policy. The president for the 2006–2007 year is Steven E. Nissen. [1] The organization has 39 chapters in the U.S. (ACC See adaptive cruise control. ) estimated that the new device-based cardiac resynchronization therapy from Medtronic, Inc. (NYSE NYSE See: New York Stock Exchange : MDT MDT abbr. Mountain Daylight Time MDT (in the US and Canada) Mountain Daylight Time MDT n abbr (US) (= mountain daylight time) → ), could potentially benefit as many as 750,000 seriously ill heart failure patients. The Multicenter InSync Randomized ran·dom·ize tr.v. ran·dom·ized, ran·dom·iz·ing, ran·dom·iz·es To make random in arrangement, especially in order to control the variables in an experiment. Clinical Evaluation clinical evaluation Medtalk An evaluation of whether a Pt has symptoms of a disease, is responding to treatment, or is having adverse reactions to therapy trial, known as MIRACLE, evaluated the therapeutic benefits of the Medtronic InSync(R) Model 8040 atrial synchronous atrial synchronous VAT Cardiac pacing adjective Referring to a dual-chamber pacemaker which senses atrial activity and paces only in the ventricle; the rate of ventricular stimulation is directly synchronized to sensed atrial activity. See Pacemaker. biventricular pacing device, the Model 9880 E software system, and the Attain(R) LV and Attain(R) CS pacing leads, in delivering cardiac resynchronization therapy. William Abraham, M.D., Chief, Division of Cardiovascular Medicine, University of Kentucky The University of Kentucky, also referred to as UK, is a public, co-educational university located in Lexington, Kentucky. Hospital, and principal clinical investigator for the MIRACLE study, said after his presentation this morning, "The InSync cardiac resynchronization system improved the functional status of heart failure patients in New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of Heart Association (NYHA NYHA New York Heart Association ) Class III and IV with concomitant left ventricular dysynchrony. These study results should bring hope to thousands of patients whose quality of life has been severely affected by heart failure. Cardiac resynchronization therapy may allow many patients who are not helped by drugs alone to resume many of their normal activities." William W. George William W. George, author of National Best Sellers True North and Authentic Leadership, is professor of Management Practice at Harvard Business School,and former Chairman and Chief Executive Officer (CEO) of Medtronic. , Chairman and CEO (1) (Chief Executive Officer) The highest individual in command of an organization. Typically the president of the company, the CEO reports to the Chairman of the Board. of Medtronic, said, "The MIRACLE study results herald the beginning of a new era in device-based therapies designed to treat advanced heart failure. The InSync system delivers cardiac resynchronization therapy to patients who are not otherwise indicated for either pacing or ICD ICD International Classification of Diseases (of the World Health Organization); intrauterine contraceptive device. ICD abbr. implantation. This means that an entirely new patient population - one that could only be managed with drugs or through major surgical intervention in the past - may have the option of benefiting from this unique, breakthrough treatment." Steve Mahle, president, Medtronic Cardiac Rhythm Management Cardiac rhythm management is a field of treatment in cardiology. The purpose is managing cardiac rhythm disorders. Usually it involves artificial pacemakers and/or implantable cardioverter-defibrillator therapy as well as antiarrhythmia drugs. , commented that the MIRACLE study results demonstrate the soundness of Medtronic's approach to heart failure management. "We intend to provide a variety of therapeutic combinations for clinicians treating heart failure so that they can select the most appropriate ones for their particular patients. The InSync family of cardiac resynchronization products -- including InSync, InSync ICD, and InSync III -- along with the Attain family of leads that Medtronic has developed specifically for these applications, will give physicians and heart failure patients multiple options in their quest to improve cardiac function, exercise capacity and quality of life." Medtronic has filed a pre-market approval (PMA PMA (papillary-marginal-attached), n a system of epidemiologic scoring of periodontal disease devised by Schour and Massler in which the symbols denote the areas involved in gingival inflammation. PMA Progressive muscular atrophy ) application with the FDA FDA abbr. Food and Drug Administration FDA, n.pr See Food and Drug Administration. FDA, n.pr the abbreviation for the Food and Drug Administration. for the InSync cardiac resynchronization system, which is investigational in the U.S. and commercially available in Europe. Results Demonstrate Functional Improvement The MIRACLE trial is the first rigorous study statistically powered to measure therapeutic benefits of cardiac resynchronization in a large number of patients with advanced systolic heart failure systolic heart failure Cardiology Heart failure with a severely reduced systolic function–LV ejection fraction of ≤35%. Cf Diastolic heart failure. and ventricular dysynchrony. As a randomized, double-blind parallel controlled trial controlled trial Clinical research A clinical study in which one group of participants receives an experimental drug while the other receives either a placebo or an approved–'gold standard' therapy. See Blinding, Double-blinded. , the study design controls for the placebo effect placebo effect n. A beneficial effect in a patient following a particular treatment that arises from the patient's expectations concerning the treatment rather than from the treatment itself. of receiving an implanted therapeutic device. The MIRACLE study was designed to primarily measure therapeutic benefits as determined by changes in New York Heart Association (NYHA) functional classification, distance walked in six minutes and patients' perceptions of improvements in quality of life. The study results reported by Dr. Abraham show that a statistically significant proportion of patients in the treatment group responded positively to cardiac resynchronization therapy delivered by the InSync system as compared to the control group, with improvements noted in all of the study's primary efficacy endpoints. These include:
-- An improvement in NYHA functional class:
Compared to baseline, 69
percent of patients in the treatment group experienced an
improvement in NYHA functional status by one or more class at six
months, versus 34 percent in the control group. This metric
represents the physician's assessment of changes observed in
patients at six months. NYHA Class III heart failure patients are
considered to be exercise-limited; Class IV heart failure patients
are symptomatic at rest. Improvements of one or more class
indicate an improved ability to perform the activities of daily
life.
-- Improvement in exercise capacity, as evidenced by an increase in
six-minute hall walk distance of fifty meters or greater:
Compared to baseline, 50 percent of patients in the treatment
group walked 50 meters or more at 6 months versus 30 percent of
patients in the control group. The six-minute hall walk represents
a standard and valid measure of exercise capacity in evaluating
treatment for heart failure patients.
-- Improvement in Quality of Life, as measured by the Minnesota
Living With Heart Failure Questionnaire.
Patients receiving cardiac resynchronization therapy experienced a
greater improvement in their quality of life. The improvements
exceed similar measurements of advanced heart failure patients
using standard medications such as beta-blockers and ACE
inhibitors.
This means that patients in the MIRACLE study, who were already
receiving standard drug therapy, felt better as a result of
cardiac resynchronization therapy.
In addition, improvements in several measures of patients' heart failure status and cardiac performance, suggestive of improvement in certain aspects of cardiac function, were observed, including: -- Reduction in systolic Systolic The phase of blood circulation in which the heart's pumping chambers (ventricles) are actively pumping blood. The ventricles are squeezing (contracting) forcefully, and the pressure against the walls of the arteries is at its highest. and diastolic Diastolic The phase of blood circulation in which the heart's pumping chambers (ventricles) are being filled with blood. During this phase, the ventricles are at their most relaxed, and the pressure against the walls of the arteries is at its lowest. volumes -- Increase in left ventricular ejection fraction -- Reduction in severity of mitral regurgitation The MIRACLE study also measured changes in a composite response that takes into account the following factors: patient survival, hospitalizations for heart failure, patients' own assessment of their heart failure status, changes in NYHA class and other characteristics. Sixty-three (63) percent of patients receiving cardiac resynchronization therapy showed improvement compared to 38 percent in the control group when measured by this composite response. "There were no measures of efficacy for which the control group did better than the treatment group," said Dr. Abraham. "Measures of effectiveness Tools used to measure results achieved in the overall mission and execution of assigned tasks. Measures of effectiveness are a prerequisite to the performance of combat assessment. Also called MOEs. See also combat assessment; mission. that are generally viewed as resistant or less susceptible to placebo effect (e.g., six-minute hall walk, metabolic exercise testing, echocardiographic assessment of left ventricular structure and function, plasma norepinephrine norepinephrine (nôr'ĕpīnĕf`rən), a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous system. levels) were significantly improved. The improvements in left ventricular ejection fraction and ventricular volumes demonstrated in this study represent a further improvement over those achieved with standard heart failure medications." Heart Failure a Growing Problem Heart failure is a major and growing health problem, with nearly five million Americans currently diagnosed, and up to 500,000 new cases each year, contributing to the estimated $38 billion to $40 billion expended to manage the disease in the United States alone. Researchers investigating the underlying pathophysiological mechanisms responsible for heart failure have identified several critical factors that contribute to its progression. Up to 50 percent of advanced heart failure patients have interventricular conduction delay or ventricular dysynchrony, which results in abnormal contraction of the heart. In addition, prolonged QRS QRS A pattern seen in an electrocardiogram that indicates the pulses in a heart beat and their duration. Variations from a normal QRS pattern indicate heart disease. Mentioned in: Bundle Branch Block duration in these patients causes abnormal septal septal /sep·tal/ (sep´tal) pertaining to a septum. sep·tal adj. Of or relating to a septum or septa. wall motion, decreased contractility contractility /con·trac·til·i·ty/ (kon?trak-til´i-te) capacity for becoming shorter in response to a suitable stimulus. contractility a capacity for becoming short in response to suitable stimulus. , reduced diastolic filling time and prolonged duration of mitral regurgitation, all of which contribute to deterioration of quality of life and are associated with increased mortality. Recent advances in drug therapy have improved cardiac function and survivability sur·viv·a·ble adj. 1. Capable of surviving: survivable organisms in a hostile environment. 2. That can be survived: a survivable, but very serious, illness. in these patients, but the great majority continues to suffer from poor exercise capacity and quality of life. While some have benefited from aggressive surgical interventions such as left ventricular assist devices and cardiac transplants, these have been restricted to a highly selected patient population. Since 1994, investigators have used cardiac resynchronization to demonstrate acute and chronic improvements in cardiac function, hemodynamic he·mo·dy·nam·ics n. (used with a sing. verb) The study of the forces involved in the circulation of blood. he parameters and symptoms. However, most studies to date were either non-randomized or smaller, single-blinded studies. The MIRACLE Study is designed to determine whether initial positive reports from pilot studies concerning cardiac resynchronization therapy would be upheld in a prospective, multicenter, one-to-one, randomized, double-blinded, controlled trial using Medtronic's InSync system. Patients who met inclusion criteria (heart failure of at least one month duration, NYHA Class III or IV, QRS duration [greater than] 130 ms, left ventricular ejection fraction of [less than] 35 percent, and not indicated for pacing or ICD therapy) were implanted with the InSync system within seven working days of their baseline evaluation. Patients were then randomized within 3 days after implant to either the control arm (cardiac resynchronization OFF) or the treatment arm (cardiac resynchronization ON) for a period of six months. All patients were programmed to ON following completion of the six-month follow-up visit and testing in their randomized mode. Forty four (44) centers, 39 in the U.S. and five in Canada, provided data obtained from 266 implanted, randomized patients in the pivotal phase of the study. A total of 132 patients were randomized to the control group (therapy OFF), while 134 were in the treatment group (therapy ON). Of these 266 patients, 244 completed their six-month follow-up at the time of Dr. Abraham's report: 119 in the control group and 125 in the treatment group. The InSync device continues under clinical investigation in the U. S. Useful in a New Patient Population "Improvements in each of the primary objectives established for the study demonstrate the value of cardiac resynchronization therapy for this particular class of heart failure patient," Dr. Abraham told the ACC audience. "The MIRACLE trial is unique in that patients selected for the study are not currently indicated for a pacemaker or an ICD." The InSync and the InSync ICD cardiac resynchronization systems, along with several models of Attain leads, are commercially available in Europe. The InSync III device and the Attain Over The Wire lead are both under clinical evaluation in Europe and Canada. InSync, InSync ICD and InSync III devices, along with the Attain leads, are currently under clinical evaluation in the United States. Those interested in additional information on clinical trials involving these devices should call Medtronic at 800-930-9374. For more information on Medtronic's heart failure news, go to www.newstream.com/cgi-bin/display_story.cgi?2367. This site will be available beginning Tuesday, March 20, 2001. Medtronic, Inc., headquartered in Minneapolis, is the world's leading medical technology company, providing lifelong solutions for people with chronic disease. Its Internet address is www.medtronic.com. Any statements made about the company's anticipated financial results and regulatory approvals are forward-looking statements subject to risks and uncertainties such as those described in the company's Annual Report and on Form 10-K for the year ended April 30, 2000. Actual results may differ materially from anticipated results. NOTE: PHOTOS, VIDEO AND BACKGROUND INFORMATION--relating to this story will be available for journalists to download beginning today at www.newstream.com. |
|
||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion