This question has generated much controversy over the years in the medical community. Recently, researchers attempted to answer this in an observational study reported in the New England Journal of Medicine. The study compared the health outcomes of more than 100,000 people who received angioplasty with stents (PCI), versus more than 86,000 people who had coronary artery bypass surgery (CABG). The people in both groups were 65 years of age or older, had coronary artery disease involving two or three vessels, and did not require emergency treatment. All participants are from the U.S.; the patient information was collected from a collaboration between the American College of Cardiology Foundation and the Society of Thoracic Surgeons. Let's review the findings.
Study Outcomes Show Small Difference
There was no significant difference in mortality between the two groups at the end of one year following the procedures. After four years, however, the death rates were lower for those in the CABG group verses the PCI group—CABG mortality was at 16.4 percent versus PCI at 20.8 percent.
Problems in Interpreting the Results of this Study
An accompanying editorial points out that the study advantages, because of its breadth and size, are counterbalanced by the likelihood that major differences between the two groups of patients could account for the better outcome with CABG. Some of the factors that might affect both the choice of procedures and the outcomes include selection bias by the patient’s cardiologist, the extent of disease in the affected coronary arteries, the patient’s degree of frailty, and the patient’s preferences. Although the study authors did attempt to determine the effects of such variables on their results, they could not overcome the possibility that one or more of them might have led to erroneous conclusions.
Results of Other Randomized Trials Add to the Confusion
In another research trial, called BARI, the cardiac mortality was lower with CABG than with angioplasty in a 10-year follow-up of patients with diabetes. A somewhat similar finding was confirmed in the "Synergy between PCI with Taxus and Cardiac Surgery trial," where there was no differenc in mortality between the two procedures in the overall group, but after 3 yearas the mortality was 3.2 percent lower with CABG in those with three-vessel disease. In contrast, in another trial CABG was not associated with a lower mortality among those with two-vessel disease or with localized blockages in three vessels.
Which procedure should you choose?
The long-term differences in mortality between the two procedures are generally relatively small. And the latest study does not clearly tip the balance in favor of CABG. However, it does appear that CABG is preferable for people with diabetes.
Those without diabetes need to rely on their cardiologist to make the better choice based on their individual medical circumstances. It is worth keeping in mind that CABG is a much more invasive procedure that is associated with more days in the hospital and considerably longer recovery period. In addition, the available comparisons between the two procedures have not included people who have undergone PCI with the latest improved techniques.