01:00 AM

Study Finds Treatment of Severe Coronary Artery Disease With Medication-Releasing Stents a Viable Alternative to CABG

Coronary artery bypass grafting (CABG) has been considered the gold standard for the treatment of  left main coronary artery disease − the most severe form of coronary artery disease − for nearly three decades.   A study conducted at Cedars-Sinai Medical Center compared the clinical outcomes of patients treated with CABG and those treated with a less invasive, medical revascularization treatment and found the rate of short- and intermediate-term major cardiac and cerebrovascular complications were comparable. The results of the study, described in the current issue of the Journal of the American College of Cardiology, suggest that further comparison between CABG and percutaneous coronary intervention (angioplasty) with medication-releasing stents may provide a basis for the re-evaluation of current treatment guidelines for left main coronary artery disease.

Los Angeles - February 23, 2006 - Severe stenosis (blockage) to the left main coronary artery − a condition commonly called a “widow-maker” − can result in sudden death. For nearly 30 years, the gold standard for treatment has been coronary artery bypass surgery (CABG).  

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, MD, 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, MD, 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.”

Citation: Journal of the American College of Cardiology, February 20, 2006, “Comparison of Coronary Artery Bypass Surgery With Percutaneous Coronary Intervention With Drug-Eluting Stents for Unprotected Left Main Coronary Artery Disease.”