Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=210813
Story Retrieval Date: 9/20/2014 7:03:00 PM CST
Courtesy of NHLBI
For adults who suffer from diabetes and heart disease, coronary bypass surgery is a better treatment option than other stent procedures, according to a new study released by the National Institutes of Health.
The five-year, international study was supported by the National Heart, Lung, and Blood Institute, a branch of the NIH.
From 2005 to 2010, the FREEDOM study (Future Revascularization Evaluation in Patients with Diabetes Mellitus) compared the effectiveness of a coronary artery bypass graft surgery and a non-surgical stent procedure known as percutaneous coronary intervention. Cardiologists enlarge arteries with a balloon to insert the small tube-like stents that hold blocked arteries open.
After five years, the patients who had undergone coronary bypass surgery had lower overall rates of stroke, death and heart attacks and better overall heart-related outcomes than those who received the non-surgical procedure, which improves blood flow to the heart.
“The results are really, very striking,” said Dr. Yves Rosenberg, project officer for the study and chief of the Atherothrombosis and Coronary Artery Disease Branch at NHLBI. “They showed a clear advantage of surgery for the group of patients we studied. The advantage was clear across the board.”
The study included 1,900 participants throughout 140 international clinical sites, according to Rosenberg. The average age of participants was 63 and more than 70 percent were male, he said.
In bypass surgery, the now preferred treatment for patients with diabetes, surgeons try to improve blood flow to the heart muscle by using a healthy artery or vein from another part of the body to bypass a blocked coronary artery. In PCI, the less invasive technique, blocked arteries are opened from the inside with a balloon. A stent is inserted to prop the opened arteries and restore the normal flow of blood to the heart.
There are short-term risks associated with the cardiac bypass procedure. Surgical patients had a slightly increased immediate risk chance of stroke, compared to those who didn't have surgery. However, the long-term benefits of increased survival and a decreased risk of heart attacks means that most patients will have an overall long-term benefit from the cardiac surgery, according to Rosenberg.
“The immediate risk [of stroke], with the next 30 days is higher with bypass surgery and that’s true for any open heart procedure compared to a stenting procedure,” said Dr. Robert Bonow, a cardiologist at Northwestern Memorial Hospital and professor at Northwestern University’s Feinberg School of Medicine. “But if you look at the numbers...the actual number of strokes was relatively low in both groups although it was higher in the patients who had the bypass operations.”
Rosenberg said that it was not clear why diabetic patients saw such a dramatic increase in longevity and a decreased risk of heart attacks after the bypass procedure. “I think we can only speculate on the reasons why we observed the benefit,” he said.
According to Rosenberg, the results could change treatment recommendations for thousands of individuals with diabetes and heart disease.
The study should drive “a very careful discussion” between a physician and their patient, “making sure the patient understands that their long-term outcome will be much better if they have surgery,” Bonow said.
“We are just reporting the results, we are not in the business of making guidelines,” Rosenberg said. “Now the guideline committees from the AHA and others will decide whether or not they need to change the recommendation for these type of patients and put much stronger recommendations for this type of surgery.”