How to revascularize patients with diabetes mellitus: bypass or stents and drugs?

The diabetic patient is at high risk for coronary artery disease. Incidence as well as severity of the disease is highly increased in comparison to non-diabetic patients. The revascularization of the diabetic patient is a great challenge, since the longterm results are disappointing when compared to non-diabetic patients. The success of coronary artery bypass grafting is limited by increased perioperative mortality and a faster occlusion of especially venous bypass grafts. In percutaneous interventions the excessive high restenosis rates worsen longterm results. Several clinical trials investigated the outcome of the two revascularization strategies and could demonstrate at least a tendency towards better results when the operative approach was chosen. Particularly, the BARI trial showed reduced mortality for surgery when compared to percutaneous coronary interventions. However, in this trial, in 87% of patients undergoing bypass surgery all stenoses were successfully treated, whereas in patients undergoing percutaneous coronary intervention only 76% of all stenoses were primarily successfully treated. In addition, no stents were used in this trial.Furthermore, the enrollment of the previous trials dates one decade ago. These trials do therefore not necessarily represent the current standard therapy, especially for percutaneous coronary interventions. The restenosis rate could be decreased in recent years by means of drug-eluting stents and an aggressive antiplatelet therapy from more than 50% to less than 10% leading to considerably improved long-term results. Therefore, percutaneous coronary interventions have developed to be a reasonable alternative to bypass surgery. Different clinical trials are currently underway (BARI 2D, CarDIA, FREEDOM) comparing the outcome of the two approaches.