The Target: Non-HDL-C?
Non–high-density lipoprotein cholesterol (non-HDL-C) levels appear to be an indicator of risk for nonfatal myocardial infarction and angina pectoris, making it a good target for lipid-lowering therapies, according to researchers in a report in this week’s issue of Circulation (Circulation. 2002;106:2537–2542).
Researchers in the Bypass-Angioplasty Revascularization Investigation (BARI), led by Vera Bittner, MD, MSPH, of the University of Alabama at Birmingham, monitored 1514 patients with multivessel coronary artery disease enrolled in BARI for 5 years. The study’s end points were death, nonfatal myocardial infarction, and death or myocardial infarction as well as angina pectoris. They found that non-HDL-C was a strong and independent predictor of nonfatal myocardial infarction and angina pectoris. However, they found that it did not predict mortality or events during follow-up. The researchers concluded: “Our data suggest that non-HDL-C is an appropriate treatment target among patients with coronary heart disease.”
Repeating Reperfusion in Brachytherapy
Iridium-192 intracoronary brachytherapy for in-stent restenosis delayed the time to target lesion re-narrowing in patients for whom the radiation treatment was not totally successful, according to researchers in a report in the October 29, 2002 issue of Circulation (Circulation. 2002;106:2340–2345). In this multicenter study, led by Ross Prpic, MBBS, from Harvard Clinical Research Institute in Boston, Mass, researchers also concluded that repeat percutaneous interventions in patients who had received brachytherapy was safe and effective in the short-term with “acceptable” long-term results.
The authors noted that as many as 24% of patients who underwent percutaneous intervention with brachytherapy require target vessel revascularization. In this analysis of the Gamma-I and Gamma-II brachytherapy trials, subjects who required revascularization of the target lesion were divided into two groups—one made up of patients who had received Iridium-192 brachytherapy and another made up of patients who had received placebo. Of the 256 patients who received brachytherapy, 45 required revascularization. Thirty-six of 121 patients who received placebo required revascularization.
The mean time to revascularization was 295±206 days in the irradiated group and 202±167 days in the placebo group. The revascularization procedure was successful in 100% of patients who had received the radiation and in 94% of those who had received placebo. However, 15 of the 45 irradiated patients and 17 of the 36 placebo patients who underwent revascularization had to undergo another procedure. There was no difference in the time to this revascularization between the two groups.
Exercise: Quantity, Not Quality? A STRRIDE Forward
Researchers in the October 31, 2002, issue of the New England Journal of Medicine (N Engl J Med. 2002; 347:1483–1492) found that the amount of exercise per week—not its intensity or the improvement in patient fitness—was most closely related to improvements in lipid profiles of patients with mild-to-moderate dyslipidemia.
In the Studies of Targeted Risk Reduction Interventions through Define Exercise (STRRIDE), led by William E. Kraus, MD, of Duke University Medical Center in Durham, NC, 111 sedentary and overweight men and women with abnormal lipid profiles were randomly assigned to participate in one of 3 exercise groups or a placebo group. The 3 exercise groups were divided on the basis of intensity. The high-amount, high-intensity group exercised a caloric amount equivalent to jogging 20 miles per week. The low-amount, high-intensity exercise group exercised a caloric amount equivalent to jogging 12 miles per week. The low-amount, moderate-intensity exercise group exercised a caloric amount equivalent to walking 12 miles per week. Those in the study were encouraged to maintain their base-line body weight.
Eighty-four subjects complied with the guidelines of the studies and were the basis for analysis. The subjects underwent detailed lipoprotein profiling by nuclear magnetic resonance spectroscopy. The measurements were verified by laboratory tests that measured lipoprotein subfractions.
Beneficial effects were seen on most subjects, but those who were in the high-amount, high-intensity exercise group achieved the greatest benefit. This group’s lipoprotein profile was always superior to those patients in the control group. The responses of the two lower exercise groups were also better than those of the placebo group.
The researchers noted that although exercise has always been associated with reduced risk of cardiovascular disease, the amount of exercise required has been in dispute. They designed their prospective study to answer this question. They concluded: “Our study demonstrates that regular exercise with minimal weight change has broad beneficial effects on the lipoprotein profile . . . The extensive improvements achieved in the high amount high-intensity group were related to the amount of physical activity and did not appear to be related to changes in the level of fitness.”
Eric Topol, MD, Receives Gill Award for Outstanding Contributions to Cardiovascular Research
Eric J. Topol, MD, has been named the 2002 recipient of the Linda and Jack Gill Heart Institute at the University of Kentucky Award for Outstanding Contributions to Cardiovascular Research. He received a plaque, a $20 000 cash prize, and the honor of a presentation at Cardiovascular Research Day 2002.
Dr Topol is Co-Director of the Cleveland Clinic Heart Center in Cleveland, Ohio, and has been a major contributor to cardiovascular research. He is a fellow of the American Heart Association, the American College of Cardiology, the American College of Physicians, the European Society of Cardiology, the Society of Cardiac Angiography, and the American College of Chest Physicians. His program in Cleveland has been ranked #1 by U.S. News & World Report for the past 8 years.
He has served as principal investigator for more than 15 international multicenter research trials. He is currently a member of the editorial board of more than 30 peer-review medical publications, including Circulation, Circulation Research, and the Journal of the American College of Cardiology.
Sirolimus-Eluting Coronary Stent Approval Recommended
Cordis’ Corporation CYPHER Sirolimus-Eluting Coronary Stent System received a recommendation for approval with conditions at the October 22-23, 2002, meeting of the Circulation System Devices Panel of the US Food and Drug Administration (FDA).
The device consists of a permanently implanted stent with a drug-polymer coating and the CYPHER Delivery Catheter System. It reduces de novo restenosis of coronary artery lesions. In a clinical study of 1058 patients randomized to two treatment arms—one a bare stent and the other the sirolimus-eluting stent—the drug-eluting stent reduced target vessel failure to 8.6% at 9 months, compared with 21% in patients who received the bare stent.
The panel voted 8-0 to approve the drug-eluting stent with conditions that included a 5-year follow-up of patients enrolled in 3 principal clinical studies that have been conducted so far. The company must also complete a pharmacokinetic study and revise patient and product labels to include more information about the drug coating. The information must also state that the vessels studied to date were 2.5 to 3.5 mm in diameter and that the lesion length was 15 to 30 mm, according to information released by the FDA.