Effect of bypass graft surgery on survival
Among the surgical approaches to myocardial revascularization which have evolved in the past quarter century, none has evoked the sustained interest nor stimulated the detailed studies of efficacy as has the bypass graft technique. That this procedure has a salutory effect upon symptoms has been generally confirmed by a number of centers. Assessment of its effect upon survival has been complicated by difficulties in designing effective, controlled randomized studies. Nevertheless, a long-term follow-up of a large surgical series may be of interest to determine if, in addition to relieving the symptoms of myocardial ischemia, surgical treatment has any apparent effect upon survival.
Long-term follow-up studies were undertaken in a group of 741 patients treated with bypass grafts at the Cleveland Clinic from May 9, 1967, through December 31, 1970. Patients with significant associated congenital or rheumatic heart disease or who had previous heart surgery, and those who had associated procedures in conjunction with their bypass graft operation were excluded. Without previously established guidelines, the selection of patients for bypass graft surgery was based upon severity of symptoms, anatomical severity of the coronary artery lesion, the number of involved vessels, and the apparent integrity of the myocardium in the region perfused by the arteries to be grafted. Certain hypotheses influenced case selection in this early series: that operations upon patients with severe preoperative myocardial damage or those requiring more complex procedures would be associated with greater operative morbidity and mortality as well as less favorable long-term results. A 100% follow-up has . . .