Your patient, Mr. Smith, is a good man with a bad heart. He’s had diabetes for years and was recently diagnosed with three-vessel coronary artery disease (CAD). Even mild exertion gives him chest pain. Now that it’s winter, he wants to shovel the driveway, but his wife (an outspoken woman) will have none of it.
“He needs help,” she says, and you agree; “but what would be best?”
You’ve had the same question and, in search of an answer, reviewed several studies: BARI, ARTS, CARDia, SYNTAX. All of them suggest that for diabetic patients with multivessel disease, coronary artery bypass grafting (CABG) is more effective than percutaneous coronary intervention (PCI).
As of last month, there is another study to consider: the Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease (FREEDOM) trial. This randomized trial enrolled 1900 patients from 140 international centers — all diabetics with multivessel coronary artery disease. Patients were randomized to undergo either CABG or PCI with a drug-eluting stent (and, in most cases, dual anti-platelet therapy) and followed for 2 to just shy of 7 years. The primary outcome was a composite of death from any cause, myocardial infarction, and stroke.
At 30 days, the primary outcome had occurred more frequently among those who had undergone CABG as compared to PCI (42 vs. 26 patients). In the longer term, however, the primary outcome occurred less frequently in the CABG group as compared to the PCI group (5-year rates of 19 versus 27%; P=0.005). This held true across all pre-specified patient sub-groups.
Taking a more detailed view of the primary outcome composite, CABG was associated with significantly lower rates of all-cause mortality (11% versus 16%; P=0.049) and myocardial infarction (6% versus 14%; P<0.001) but a higher rate of stroke as compared to PCI (5-year rates of 5% versus 2½%; P=0.03), with the excess of strokes occurring in the first 30 days.
These findings affirm those of previous studies: among diabetics, CABG seems overall to be a better option than PCI for revascularization.
NEJM Executive Editor Gregory D. Curfman, M.D., states: “Despite the higher rate of stroke with CABG, as compared with PCI, the higher mortality and MI rates with PCI support the recommendation for CABG in diabetics with multivessel CAD.”
And so you make up your mind on what to tell Mr. Smith and his wife. You remind them that diabetics tend to do worse after revascularization as compared to non-diabetics — whether with CABG or PCI. You warn them that stroke is a serious risk, especially with CABG, and especially right after the procedure. That being said, you still recommend that Mr. Smith opt for the CABG: for long-term freedom from major cardiovascular events, all signs suggest it will be his best bet.
How do you approach revascularization in your diabetic patients with multi-vessel disease, as compared to their non-diabetic counterparts? When do you use CABG versus PCI? How will the results of the FREEDOM trial influence your practice?
For more on this topic, see the accompanying editorial from Dr. Mark Hlatky at Stanford University School of Medicine.