New study shows that bypass surgery is more successful than stents in heart surgery

May 26 2005

A study of nearly 60,000 patients has found that people with several clogged heart arteries did better if they had bypass surgery rather than a less-drastic procedure in which the blood vessels are propped open with tiny mesh cylinders called stents.

According to the study those who underwent surgery were significantly more likely to survive and less likely to need repeat procedures.

Experts say however, that both techniques have improved so much since the study was done that more research may be needed to determine which method works best for which patients.

The study is one of the largest to compare ways of treating clogged arteries, which can lead to a heart attack.

Open-heart bypass surgery, in which blood vessels are taken from another part of the body and grafted into place to create detours around blockages, is one solution, but a less drastic alternative is angioplasty and stenting, in which tiny mesh tubes are threaded into arteries to keep them flowing smoothly.

Angioplasty is often done in people with only one or two blockages, and many studies suggest that no harm is done if it is tried first, in an effort to avoid surgery, in people with multiple blockages. The new research is now questioning this.

The study looked at patients treated for multiple blockages in New York between 1997 and 2000, and found that the patients who had surgery were 24 percent to 36 percent more likely than the others to be alive after three years.

Of those patients who received stents, 8 percent later needed surgery and 27 percent needed another stent procedure, while only around 5 percent of surgery patients needed a follow-up procedure.

Lead researcher Edward Hannan of the State University of New York at Albany says that for those people who have two alternatives, bypass surgery appears to be superior.

Bernard Gersh and Dr. Robert Frye of the Mayo Clinic College of Medicine in Rochester, Minn., however say that previous studies have suggested that only diabetics did worse when given stent procedures instead of surgery, and they beleive the implications of the study are profound and suggest that things are not as clear-cut as originally thought.

Stents have improved remarkably in recent years, and unlike the plain old metal stents, the new devices are drug-coated, allowing medication to drip into blood vessels to keep them open from squeezing shut after procedures to remove blockages.

Improvement has also been seen in bypass surgery which was traditionally performed by stopping the heart and putting the patient on a heart-lung machine. Now many patients can have so-called beating heart surgery, in which the heart continues pumping during the operation.

Very few patients received drug-coated stents or the newer bypass procedure in the New York study.