J Thorac Cardiovasc Surg 1997;113:614-615
© 1997 Mosby, Inc.
Predicting survivorship after coronary artery bypass grafting in patients with low ejection fraction
Andrew S. Wechsler, MD
Medical College of Virginia
P.O. Box 980645
Richmond, VA 23298-0645
Reply to the Editor:
The response to my editorial by Dr. Morita and his colleagues is much appreciated. I was aware of their article before the time of my writing. They are to be commended for taking on a tough task and using a sound method for establishing a predictive index of long-term survival after coronary bypass grafting in patients with reduced ejection fraction. The concept of factor analysis is sound and can serve as an amplifier of parameters that are independently of marginal significance but which, when combined, become more meaningful. Their article had a few shortcomings, which they acknowledged. These include the retrospective nature of their study, small numbers that may have been inadequately powered to detect important differences between groups, and an absence of focus on perioperative mortality. The wisdom of their approach was in combining an exercise variable that served as a surrogate for the efficacy of adaptive mechanisms in compensating for diminished ejection fraction in their patient population. As regards predicting operative mortality, similar measured parameters should be helpful but might be better analyzed in cohorts of patients in which the focus is even more heavily on those with low ejection fractions. In addition, readers of all such articles are reminded that every patient entered into the series passed an initial screening test that suggested to the surgeon the likelihood of a good outcome from operative intervention.
