A study conducted at Cedars-Sinai Medical Center, however, suggests that angioplasty with coronary stenting may be a viable alternative treatment to more complicated bypass surgery for patients with left main coronary artery (LMCA) disease when medication-releasing stents are used. Introduced two years ago, these types of stents slowly release medication that helps to prevent reclosure of the coronary artery.
The study reports on the short- and intermediate-term clinical outcomes of 123 patients who underwent bypass surgery and 50 who were treated medically with angioplasty and medication-releasing stents, also called drug-eluding stents. None of the patients had prior bypass surgery.
"Despite the greater percentage of high risk patients in the group who underwent coronary stenting, there was no increase in the immediate or medium-term complications compared with the group treated with bypass surgery," said Raj Makkar, M.D., director of the Interventional Cardiology and Cardiac Catheterization Laboratory at Cedars-Sinai, and principal investigator on the study. According to Makkar, this is one of the first studies in the United States on the use of medicated stents for the treatment of LMCA disease. LMCA disease is found in five to seven percent of patients who undergo angiography.
The American College of Cardiology and the American Heart Association have discouraged the medical treatment of left main coronary artery disease based on poor clinical outcomes. The authors suggest that a re-evaluation of the optimal treatment for LMCA disease be considered based the results of this study and on recent data showing that angioplasty with drug-eluding stents provides better outcomes than bare-metal stenting for LMCA disease.
Compared to the bypass surgery group, the group treated with drug-eluding stents had more patients with chronic renal insufficiency and more patients with unstable angina as the presenting symptom. Forty-six percent of the bypass surgery group was considered high-risk patients compared to 64 percent in the group treated with drug-eluting stents.
Patients treated with bypass surgery had longer hospitalizations and, after one-month, had a higher percentage of strokes, but there was no statistically significant difference in mortality or myocardial infarction. Six months after treatment, there had been seven deaths in the bypass surgery group and two in the group treated medically.
"The most important finding in this study is that, in a pilot experience with unprotected (no prior CABG surgery) LMCA disease, treatment with drug-eluting stents resulted in outcomes at least equivalent to bypass surgery ," said P. K. Shah, M.D., director of the Division of Cardiology at Cedars-Sinai. "At present, however, it is not known whether the improved outcomes in the drug-eluting stent group will be extended to all patients with LMCA disease. The results suggest a randomized comparison between the two revascularization strategies may be warranted."
Dr. Makkar agrees. "This study, while encouraging, suggests the need for larger randomized trials," he said. "We are currently in the process of doing such a study."
The first of eight hospitals in California whose nurses have been honored with the prestigious Magnet designation, Cedars-Sinai Medical Center is one of the largest nonprofit academic medical centers in the Western United States. For 18 consecutive years, it has been named Los Angeles' most preferred hospital for all health needs in an independent survey of area residents. Cedars-Sinai is internationally renowned for its diagnostic and treatment capabilities and its broad spectrum of programs and services, as well as breakthroughs in biomedical research and superlative medical education. It ranks among the top 10 non-university hospitals in the nation for its research activities and was recently fully accredited by the Association for the Accreditation of Human Research Protection Programs, Inc. (AAHRPP). Additional information is available at www.cedars-sinai.edu.
Journal
Journal of the American College of Cardiology