Recent insights into the treatment of stable CAD : FFR-guided PCI vs. medical therapy

[Percutaneous coronary intervention versus bypass surgery in patients with diabetes and multivessel coronary disease. Coronary revascularization after FREEDOM]

Is coronary revascularization required in a patient with chronic stable coronary artery disease or can optimized medical therapy (OMT) alone be a sufficient alternative? This question has been controversially discussed for non-diabetics as well as for diabetics since the COURAGE and BARI 2D trials. According to our present knowledge, a patient will benefit from coronary revascularization only when either a non-invasive test method, such as single photon emission computed tomography (SPECT) or positron emission tomography (PET) myocardial scintigraphy, stress echocardiography or stress nuclear magnetic resonance imaging, can detect relevant, objective evidence of ischemia >10% of the left ventricular myocardium or when a pathological fractional flow reserve (FFR) <0.80 can be measured in an invasive procedure for an angiographically detectable coronary stenosis. If similar relevant ischemia can be non-invasively or invasively objectified in a patient with chronic stable multivessel coronary artery disease, the often controversially discussed question arises particularly in diabetics whether a percutaneous coronary intervention (PCI) with implantation of drug-eluting stents or coronary artery bypass surgery should be favored. The FREEDOM study (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease), published in November 2012, was the first prospective randomized study to examine this issue in diabetic patients with multivessel coronary artery disease. Despite a higher rate of stroke in the surgical cohort, after an average follow-up time of 3.8 years a significant prognostic advantage in favor of bypass surgery was detected for a combined primary endpoint of all-cause mortality, nonfatal myocardial infarction and nonfatal stroke. Thus, in the new ESC guidelines on diabetes, pre-diabetes and cardiovascular diseases developed with the EASD of the European Society of Cardiology and published in 2013, coronary bypass surgery has a class I, level of evidence A recommendation for patients with diabetes mellitus, chronic stable multivessel coronary disease and a synergy between PCI with taxus and cardiac surgery (SYNTAX) score >22. The decision for or against a PCI/stent implantation or coronary bypass surgery in a diabetic patient with chronic stable multivessel coronary artery disease should therefore be made with the patient only after a detailed informed consent discussion and comprehensive explanation of both treatment options. In controversial cases, particularly with an equivocal SYNTAX score around 22, relevant comorbidities or anticipated method-specific complications, a one-stage ad hoc intervention during the diagnostic coronary angiography should be rejected in favor of a two-stage procedure with prior discussion of both treatment options in the heart team comprising noninvasive cardiologists, interventional cardiologists and cardiac surgeons.

Efficacy and safety of sirolimus-eluting stents versus bare-metal stents in coronary artery disease patients with diabetes: a meta-analysis

OBJECTIVE

To compare by meta-analysis the efficacy and safety of sirolimus-eluting and bare-metal stents in coronary artery disease (CAD) patients with diabetes.

METHOD

PubMed, MEDLINE and EMBASE were searched from 1971 to 2012. Data on the efficacy and safety of sirolimus-eluting and bare-metal stents in patients with diabetes were collected. A meta-analysis was then performed on a total of 1 259 CAD patients with diabetes from six studies. The odds ratio (OR) was used for comparison. Subgroup analysis was performed according to the sample size, year of study, subjects' geographic area and study method.

RESULTS

Compared with those in the bare-metal stent group (BMS), the subjects in the sirolimus-eluting stent (SES) group had a reduced risk for major cardiac events [OR 0.42, 95% confidence interval (CI): 024-0.74, p < 0.01] and target-lesion revascularisation (OR 0.26, 95% CI: 0.11 - 0.59, p < 0.01). There was no difference for myocardial infarction (OR 0.92, 95% CI: 0.61-1.40, p > 0.05) or mortality (OR 1.19, 95% CI: 0.74-1.92, p > 0.05). Subgroup analysis showed a significant difference for overall risk of major cardiac events between SES and BMS when the sample size was ≤ 90 (OR 0.28, 95% CI: 0.16-0.48, p < 0.01), when it was a randomised control trial (RCT) (OR 0.28, 95% CI: 0.19-0.42, p < 0.01), or when it was performed on European subjects (OR 0.45, 95% CI: 0.27-0.77, p < 0.01). The sensitivity was not different when one study was removed at a time.

CONCLUSION

Our study confirmed that SES are safer and more effective than BMS in CAD patients with diabetes, as far as major cardiac events are concerned.