Patients who have graft failure after CABG are more likely to have heart attacks
February 24, 2012 - Patients who had graft failures typically had more co-existing health conditions and were more likely to have their veins removed via an endoscopic procedure.
Cardiologists frequently treat blockages in coronary arteries with coronary artery bypass graft (CABG) surgery. For the surgery, clinicians remove or redirect blood vessels from other areas of the body and then reroute blood flow to the heart through those grafted blood vessels.
However, these grafts have a high failure rate and patients often must undergo additional revascularization procedures. There is limited information about how graft failures affect long-term clinical outcomes. In a new study, researchers used the PREVENT IV trial database to analyze the rates of heart attacks and deaths in more than 1800 patients who had CABG surgeries, comparing patients who had graft failures with those who did not.
The results were published in the February 14 issue of Circulation. The DCRI’s Renato Lopes, MD, PhD, (pictured, right) was the lead author.
Compared with patients who did not have graft failure (56 percent), patients who did have graft failure (44 percent) were more likely to have to undergo additional revascularizations and to have a heart attack within 18 months. Of the patients who had graft failures, almost 6 percent needed additional revascularizations, compared with 2 percent of patients who did not have graft failure but needed further revascularization. Additionally, 3 percent of patients who had graft failure had a heart attack within 12 months of the CABG surgery, compared with the 0.5 percent of patients who had heart attacks but no graft failures.
The researchers also noted that patients who had graft failures typically had more co-existing health conditions and were more likely to have their veins removed via an endoscopic procedure. There was not an association between graft failures and increased risk of death.
Due to the high rate of graft failure, the researchers stressed the importance of improving the length of time that grafted veins remain unblocked by selecting good-quality conduits and preventing injury to the veins when they are initially removed. Medications and lifestyle modifications could also help improve the graft success rate. The researchers said further studies are needed to identify therapies and strategies that will reduce graft failures after CABG surgeries.
The DCRI’s Rajendra Mehta, MD; Gail Hafley; Judson Williams, MD; Eric Peterson, MD; Robert Harrington; Michael Gibson, MD; Robert Califf, MD; and John Alexander, MD were also authors of the manuscript. Dr. Alexander was the senior author.