Revascularization Strategies in Patients with Diabetes and Acute Coronary Syndromes

PURPOSE OF REVIEW

To review the current evidence for coronary revascularization in patients with diabetes mellitus (DM) in the setting of an acute coronary syndrome (ACS).

RECENT FINDINGS

In patients with DM and stable multivessel ischemic heart disease, coronary artery bypass graft surgery (CABG) has been observed to be superior to percutaneous coronary intervention (PCI) in long-term follow-up, leading to lower rates of all-cause mortality, myocardial infarction, and repeat revascularization. In the ACS setting, PCI remains the most frequently performed procedure. In patients with an ST-segment-elevation myocardial infarction (STEMI), primary PCI should be the revascularization method of choice, whenever feasible. Controversy still exists regarding when and how to deal with possible residual lesions. In the non-ST-segment-elevation (NSTE) ACS setting, although there are no data from randomized controlled trials (RCTs), recent observational data and sub-analyses of randomized studies have suggested that CABG may be the preferred approach for patients with DM and multivessel coronary disease. There is a paucity of RCTs evaluating revascularization strategies (PCI and CABG) in patients with DM and ACS. CABG may be a viable strategy, leading to improved outcomes, especially following NSTE-ACS.

Role of Trimetazidine in Ischemic Preconditioning in Patients With Symptomatic Coronary Artery Disease

Ischemic preconditioning (IP) is a powerful cardioprotective cellular mechanism that has been related to the "warm-up phenomenon" or "walk-through" angina, and has been documented through the use of sequential exercise tests (ETs). It is known that several drugs, for example, cromokalim, pinacidil, adenosine, and nicorandil, can interfere with the cellular pathways of IP. The purpose of this article is to report the effect of the anti-ischemic agent trimetazidine (TMZ) on IP in symptomatic coronary artery disease (CAD) patients.We conducted a prospective study evaluating IP by the analysis of ischemic parameters in 2 sequential ETs. In phase I, without TMZ, patients underwent ET1 and ET2 with a 30-minute interval between them. In phase II, after 1 week of TMZ 35 mg twice daily, all patients underwent 2 consecutive ETs (ET3 and ET4). IP was considered present when the time to 1.0-mm segment ST on electrocardiogram deviation (T-1.0 mm) and rate pressure product (RPP) were greater in the second of 2 tests. The improvement in T-1.0 mm and RPP were compared in the 2 phases: without TMZ and after 1-week TMZ to assess the action of such drug in myocardial protective mechanisms. ETs were analyzed by 2 independent cardiologists.From 135 CAD patients screened, 96 met inclusion criteria and 62 completed the study protocol. Forty patients manifested IP by demonstrating an improvement in T-1.0 mm in ET2 compared with ET1, without the use of any drugs (phase I). In phase II, after 1-week TMZ, 26 patients (65%) did not show any incremental result in ischemic parameters in ET4 compared with ET3. Furthermore, of these patients, 8 (20%) had IP blockage.In this study, TMZ did not add any benefit to IP in patients with stable symptomatic CAD.