The prevalence of diabetes mellitus has assumed epidemic proportion in Western countries as well as in the rest of the world. Coronary artery disease (CAD) is quite common in adults with diabetes mellitus and is a major cause of morbidity and mortality in them.
For patients with multivessel coronary artery disease, revascularization procedures like coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI) with drug-eluting stent (DES) are commonly performed. Diabetic patients undergoing such procedures experience worse outcomes than non-diabetic patients.
AdvertisementDuring CABG, a healthy artery or vein from the body is connected, or grafted, to the blocked coronary artery. The grafted artery or vein bypasses the blocked portion of the coronary artery, thus creating a new path for oxygen-rich blood to flow to the heart muscle.
PCI, which is also known as angioplasty, is a procedure where a deflated balloon is passed via a catheter through blood vessels until it reaches the site of blockage. Here, the balloon is inflated to open the artery, allowing blood to flow. A stent is usually placed at the site of blockage to keep the artery open. Drug-eluting stents release a drug like sirolimus or paclitaxel that prevents restenosis.
Several trials have been conducted in the past few decades to understand as to which mode of revascularization (CABG or PCI) is safer. One such recent trial was the FREEDOM trial (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease), which was published in the New England Journal of Medicine. The main objective of the study was to evaluate whether PCI with drug-eluting stents (PCI/DES) is more or less effective than the existing standard of care, CABG, in patients with diabetes mellitus.
The study enrolled 1900 adults with diabetes mellitus (Type 1 or Type 2) with angiographically confirmed multivessel CAD. The patients' mean age was 63.1ą9.1 years; 29% participants were women, and 83% had three-vessel disease. The participants were randomly assigned to receive one of the interventions.. The PCI group also received anti-clotting therapies.
The study found that there was increased all-cause mortality in the PCI group (16.3% in the PCI group versus 10.9% in the CABG group) at the end of a 5-year period. It was also seen that 13.9% of patients in the PCI group had a myocardial infarction, as compared with 6% in the CABG group. However, there were fewer strokes in the PCI group (2.4%) than in the CABG group (5.2%)
There was also a significant difference in rates of major adverse cardiovascular and cerebrovascular events at 1 year after the procedure, with 16.8% in the PCI group versus 11.8% in the CABG group suffering from these adverse events.
Based on the results of the trial, it was concluded that CABG was superior to PCI with drug-eluting stents in patients with diabetes and multivessel coronary artery disease as CABG significantly reduced rates of death and myocardial infarction. However, it was associated with a higher rate of stroke.
Reference: Strategies for Multivessel Revascularization in Patients with Diabetes; Michael Farkouh et al; N Engl J Med 2012; 367:2375-2384