So concludes a study in today's issue of the Journal of the American College of Cardiology.
The study found that bypass surgery offered better results for people with high-grade artery lesions. However, the study didn't compare bypass surgery to newer stents.
Dutch and Italian researchers studied 102 people with a single B2 or C lesion in a coronary artery. The patients were randomly assigned to receive either angioplasty or bypass surgery.
Those who received angioplasty had a catheter threaded into the narrowed artery to restore blood flow. A wire mesh stent was then left in place to keep the artery open.
The bypass surgery patients had a "keyhole" type of operation. The surgeon worked through a small incision in the chest and grafted a bypass vessel around the blocked artery.
Three years after the procedures, the researchers counted the number of patients who had died, suffered a heart attack or stroke, and those who needed a second procedure because of a clog in the same artery.
The study found that 23.5 percent of the people who received angioplasty had a heart attack, stroke or needed a second procedure, compared to 9.8 percent of the people who had bypass surgery.
However, there were no deaths in the angioplasty group, compared to two deaths in the bypass surgery group.
The study also found that people in the bypass surgery group were less likely to have a return of angina, needed much less medication, and were in better condition than the angioplasty/stent group.
The American Heart Association has a full explanation of coronary bypass surgery.