Open vs Endo: The muddied waters of diabetic revascularization are clearing.

TORONTO — Diabetics with blocked arteries should have bypass surgery instead of having a stent inserted, says a new study led by doctors at Toronto's St. Michael's Hospital.

The study, which pooled data from eight clinical trials, found that diabetics who had bypass surgery were about 33% more likely to be alive five years later than those who had a stent insertion.

Doctors have increasingly opted for the less invasive stent procedure in recent years — but questions have remained about whether the stents are good for diabetics.

The study authors say doctors should consider the substantial survival advantage of the bypass surgery for diabetics needing artery-opening procedures.

"It is a pretty significant effect. It’s startling to think that there's still some debate about this when results like these (with such) significant differences are coming out," says cardiac surgeon Dr David Latter, one of the study’s authors,

Higher mild stroke risk

The survival effect was large, but there was a hitch. The study also found that the diabetic patients who had bypass surgery were 1.75 times more likely to have a non-fatal stroke in the five years after the procedure than those who had a stent instead.

That increased risk may be related to having undergone surgery and could also be linked to lower use of anti-clotting drugs in the surgical patients.

Dr Gideon Cohen, head of cardiac surgery at Sunnybrook Health Sciences Centre in Toronto, says that while it's tempting to take care of blockages right away by using the non-invasive stent procedure for diabetics, doctors should inform their patients about the risks.

"Sometimes we don't give patients enough credit to make the most well-informed decisions," he says.

He stressed that the discussions about the pros and cons for both procedures should take place before the test is done.

"The conversation absolutely has to be had before the procedure."