CAB Surgery May Be Superior to Stents Long Term
DENVER—Drug-eluting stents (DES) provide the best short-term survival for dialysis patients who require coronary revascularization, but coronary artery bypass (CAB) surgery may offer better long-term survival, researchers reported at the 2010 Renal Week conference.
“Depending on the time frame you look at it, the outcomes are different. The outcome is better for drug-eluting stents if you look at the short-term follow up, but better for surgery with the long-term follow-up,” said Charles Herzog, MD, Professor of Medicine at the University of Minnesota and Director of the Cardiovascular Special Studies Center at the U.S. Renal Data System (USRDS), both in Minneapolis. “The reason is that there is a higher perioperative mortality associated with surgery, about 8.5%.”
These findings are significant because few studies have looked at the comparative long-term survival of dialysis patients undergoing surgical versus percutaneous revascularization in the era of DES, Dr. Herzog said. Using the USRDS database, he and his colleagues identified 10,941 dialysis patients who had CAB or DES in 2004-2006. Of these 3,455 CAB patients and 7,486 DES patients met study enrollment criteria. Researchers followed up patients through the end of December 2008. The primary endpoint was all cause mortality.
DES patients had better survival at 12 months. After 18 months, however, survival was better in the CAB group. CAB patients receiving internal mammary grafts (68% of CAB patients) had significantly better survival than those without internal mammary grafts (IMG). The overall risk of death was 14% lower with CAB plus IMG versus CAB alone.
The survival rate at one month post intervention was 88% for CAB patients and 93% for DES patients; at six months, it was 75% and 81%, respectively. At 12 months, however, the rates were 68% for CAB compared with 70% for DES. The rates were 55% and 52%, respectively, at 24 months and 34% and 30%, respectively, at 48 months.
“There are a couple of take-home messages,” Dr. Herzog said. “First, the benefit with surgery really accrues with patients who have internal mammary grafts. The second message is that it depends on the patient's viewpoint. Some dialysis patients would say it is really a quality of life issue: ‘I really don't want to be in the hospital very long. I don't want to be exposed to higher risk of a stroke and I want to have my procedure done and get out as soon as possible.'”
Clinicians may need to take more time to explain to patients that the long-term benefits may be better with CAB, said Dr. Herzog, who presented study findings. As a result of the study, clinicians now have specific numbers they can give their patients concerning this issue.