PLYMOUTH MEETING, Pa., Jan. 16 /PRNewswire/ -- Laser revascularization procedures may be effective for reducing angina symptoms and improving quality of life, but their impact on overall survival rates remains unclear, according to ECRI, a nonprofit health services research agency. ECRI's recent technology assessment report examines the available published evidence on the effectiveness of surgical transmyocardial laser revascularization (TMR) and a more recent form of the procedure, percutaneous (catheter-based) myocardial revascularization (PMR) for treating angina, when compared to or combined with standard medical therapy. The assessment also evaluates available research on the procedures' morbidity and mortality rates, patient indications and contraindications, and the safety and effectiveness of TMR versus PMR.
Angina pectoris occurs when coronary artery disease or other conditions reduce the available blood-flow capacity of the heart's coronary arteries. This reduces oxygen delivery to tissues, resulting in a painful pressure sensation in the chest area. Standard procedures to treat angina include angioplasty with stent placement or coronary artery bypass grafting (CABG), but many angina patients are not candidates for these procedures. They may, however, be candidates for TMR, a minimally invasive surgery, or PMR, a nonsurgical procedure performed percutaneously via a catheter. Both procedures involve use of a laser beam to drill as many as 40 channels through the heart muscle into the ventricular cavity. The lasers used for TMR are approved by the U.S. Food and Drug Administration (FDA) for use in patients with severe chest pain who cannot undergo CABG or angioplasty. The laser used for PMR is not yet approved for marketing in the United States, but is under consideration for marketing approval by the FDA.
ECRI found that when combined with medical therapy, TMR and PMR are more effective than medical therapy alone in relieving angina symptoms and improving quality of life, although neither procedure has been shown to improve one-year survival. Both procedures appear to be reasonably safe in patients who are not candidates for conventional revascularization procedures. Although no trials directly compared TMR and PMR, ECRI's analysis found that there did not appear to be a difference in survival rates for patients receiving TMR and those receiving PMR, although the perioperative mortality rate may be lower with PMR because the procedure is less invasive. TMR was associated with a higher rate of angina reduction, but this may be explained by differences in the patients enrolled in the trials. Because indirect comparisons made using different studies are inherently less valid than direct comparisons made within a trial, these conclusions need to be verified in a trial that directly compares TMR and PMR.
Many surgeons are now performing TMR on CABG recipients and combining both treatments in a single surgical procedure, according to a recent article in The New York Times(1). Although this combined surgery is considered an "off label" use of TMR, it now represents the most common use of the procedure, according to a recently published study cited in the article. The article reported that the combination surgery may present increased risk to patients, but this conclusion may have been incorrectly based on death rates of patients who had received TMR alone and were not candidates for CABG. However, these TMR patients typically have no conventional treatment options other than the continuation of medical therapy, which is generally ineffective in this population. They have a high mortality and morbidity risk even without any surgery, and are generally not comparable to patients who are candidates for CABG. ECRI's assessment of the available evidence found that for certain patients who are candidates for the combined procedure, TMR plus CABG may actually be safer and more effective than CABG alone.
ECRI's technology assessment reports are published as part of ECRI's Health Technology Assessment Information Service (HTAIS). HTAIS functions as a member-funded cooperative for the development of technology assessment reports. Members include hospitals, healthcare providers and health systems, managed care organizations, and state and federal government and international agencies.
For more information about HTAIS, or to purchase a copy of "Transmyocardial Laser Revascularization (TMR)/Percutaneous Myocardial Laser Revascularization (PMR) for Treatment of Refractory Angina," contact ECRI by mail at 5200 Butler Pike, Plymouth Meeting, PA 19462-1298, USA; by telephone at +1 (610) 825-6000, ext. 5170; by e-mail at communications@ecri.org; or by fax at +1 (610) 834-1275. For more information about HTAIS, visit ECRI's Web site at http://www.ecri.org/. ECRI's European office can be contacted at info@ecri.org.uk, ECRI's Malaysian office can be contacted at s.e.asia@ecri.org, and ECRI's Middle Eastern office can be contacted at middleeast@ecri.org.
ECRI (http://www.ecri.org/), a nonprofit international health services research agency, is a Collaborating Center of the World Health Organization and an Evidence-based Practice Center as designated by the U.S. Agency for Healthcare Research and Quality. ECRI provides information and technical assistance to the healthcare community to support safe and cost-effective patient care.
(1) "Heart Laser Treatment Used Mostly on Patients Who Don't Meet the Federal Criteria," The New York Times, November 6, 2003
ECRICONTACT: Media Contact: Sarah Vincent, +1-610-825-6000, ext. 5346, orFor purchasing information, contact: Don Cummins, +1-610-825-6000, ext. 5170,both of ECRI
Web site: http://www.ecri.org/