Author + information
- Received February 3, 1986
- Revision received April 30, 1986
- Accepted May 16, 1986
- Published online October 1, 1986.
- Donald A. Weiner, MD, FACC†,**,
- Thomas J. Ryan, MD, FACC†,
- Carolyn H. McCabe, BS†,
- Bernard R. Chaitman, MD, FACC‡,
- L. Thomas Sheffield, MD, FACC§,
- Lloyd D. Fisher, PhD‖ and
- Felix Tristani, MD, FACC#
- ↵**Address for reprints: Donald A. Weiner, MD, Section of Cardiology, University Hospital, 75 East Newton Street, Boston, Massachusetts 02118.
To determine whether exercise testing can identify patients whose survival might be prolonged by coronary artery bypass surgery, the results of bypass surgery were compared with those of medical therapy alone in 5,303 nonrandomized patients from the Coronary Artery Surgery Study registry who underwent exercise testing. Patients in the two treatment groups differed substantially with regard to important baseline variables. Analysis of 32 variables by Cox's regression model for survival revealed an independent beneficial effect of bypass surgery on survival (p < 0.00001). Patients were then stratified into subsets according to the results of exercise testing.
Surgical benefit was greatest in the 789 patients who exhibited at least 1 mm of ST Segment depression and who could exercise only into stage 1 or less. Among the 398 patients with three vessel coronary disease showing these characteristics, 7 year survival was 58% for the medical group and 81% for the surgical group (p < 0.001). There was no difference in survival between the surgical and medical groups among the 1,545 patients without ischemic ST segment depression Who were able to exercise into stage 3 or greater. Thus, in patients who demonstrate ischemia on exercise testing and whose exercise capacity is limited, coronary bypass surgery appears to improve survival in comparison with medical therapy alone.
↵† From the Evans Memorial Department of Clinical Research and the Department of Medicine, University Hospital, Boston, Massachusetts
↵‡ Department of Medicine, St. Louis University, St. Louis, Missouri
↵§ Department of Medicine, University of Alabama in Birmingham, Birmingham, Alabama
↵‖ Department of Biostatistics and Medicine, University of Washington, Seattle, Washington
↵# Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin.
* A list of participating clinical sites and investigators appears in the Appendix.
- Received February 3, 1986.
- Revision received April 30, 1986.
- Accepted May 16, 1986.
- American College of Cardiology Foundation