DALLAS — Data from past and present literature indicate that optimal medical therapy is a proven option for treating patients with diabetes and stable coronary artery disease, according to data presented by William S. Weintraub, MD, FACC, of Christiana Care Health System in Wilmington, Del.
In particular, atherosclerosis is a progressive disease, and diabetes substantially increases the risk for developing vascular disease and vascular events, according to Weintraub.
William S. Weintraub
“Its pathophysiology is complex and involves endothelial, vascular smooth muscle cell, platelet function and increased prothrombotic factors,” Weintraub said during a symposium on diabetes and cardiovascular disease controversies at AHA 2013.
Diabetes and vascular disease
There are metabolic abnormalities such as decreased bioavailability of nitric oxide, increased oxidative stress and disturbances of intracellular signal transduction, Weintraub said.
“Patients with diabetes are different. These abnormalities contribute at the cellular level, increase atherosclerosis and increase the risk of CV events, making this a complex disease to treat medically and difficult to treat with revascularization,” he said.
Weintraub presented data from the COURAGE trial, which has been criticized for being a trial in patients without the highest risk.
“These are patients for whom we were considering for revascularization with percutaneous coronary intervention vs. medical therapy. Nonetheless, the event rate if you compare this to recent trials, diabetes was a large subgroup; 34% in COURAGE had diabetes,” Weintraub said.
There were no statistically significant differences between optimal medical therapy and percutaneous coronary intervention (PCI) for the survival free of death from any cause and MI (HR=1.05; 95% CI, 0.87-1.27); no differences in overall survival (HR=0.87; 95% CI, 0.65-1.16); and no difference in freedom from myocardial infarction (HR=1.13; 95% CI, 0.89-1.43), according to data.
Weintraub also cited data from the BARI 2D trial, which compared revascularization with PCI and coronary surgery for patients with diabetes, and the PROSPECT study. He said patients with diabetes have a more diffusive disease when it comes to CV event rates.
Key questions remain
Despite recently published data, Weintraub said the following critical questions remain:
- Is it ischemia or the vulnerable plaque that predicts future MI?
- If it is the vulnerable plaque, what is the role of revascularization in stable ischemic heart disease (SIHD)?
- Can PCI stabilize a vulnerable plaque and prevent rupture and an ensuing event?
- If PCI can do this, technically, can we find them?
- Are there special considerations about PCI for patients with diabetes?
Weintraub said coronary artery bypass graft (CABG) in COURAGE and BARI 2D and other trials have shown that it is possible to defer revascularization. However, there is not an established medical necessity to revascularize all patients with SIHD and obstructive disease. He added that there remains uncertainty about revascularization in patients with large ischemic burden.
“Plaque rupture leading to MI does not necessarily occur at sites of obstructive disease,” he said. “It would be, perhaps, appropriate to target revascularization in SIHD for patients at high risk for an event, but the ability to predict events is limited to models.”
Weintraub said it is the responsibility of clinicians to treat risk factors, and therapeutic lifestyles are the true cornerstone of therapy.
For more information:
Weintraub W. AHA Cardiovascular evening symposium: CVES.01. Diabetes and cardiovascular disease: current controversies. Presented at: the American Heart Association Scientific Sessions; Nov. 16-20, 2013; Dallas.
Disclosure: Weintraub reports no relevant financial disclosures.