Reduced risk of myocardial infarct and revascularization following coronary artery bypass grafting compared with percutaneous coronary intervention in patients with chronic kidney disease.

Coronary atherosclerotic disease is highly prevalent in chronic kidney disease (CKD). Although revascularization improves outcomes, procedural risks are increased in CKD, and unbiased data comparing coronary artery bypass grafting (CABG) and percutaneous intervention (PCI) in CKD are sparse. To compare outcomes of CABG and PCI in stage 3 to 5 CKD, we identified randomized trials comparing these procedures. Investigators were contacted to obtain individual, patient-level data. Ten of 27 trials meeting inclusion criteria provided data. These trials enrolled 3993 patients encompassing 526 patients with stage 3 to 5 CKD of whom 137 were stage 3b-5 CKD. Among individuals with stage 3 to 5 CKD, mortality through 5 years was not different after CABG compared with PCI (hazard ratio [HR] 0.99, 95% confidence interval [CI] 0.67-1.46) or stage 3b-5 CKD (HR 1.29, CI 0.68-2.46). However, CKD modified the impact on survival free of myocardial infarction: it was not different between CABG and PCI for individuals with preserved kidney function (HR 0.97, CI 0.80-1.17), but was significantly lower after CABG in stage 3-5 CKD (HR 0.49, CI 0.29-0.82) and stage 3b-5 CKD (HR 0.23, CI 0.09-0.58). Repeat revascularization was reduced after CABG compared with PCI regardless, of baseline kidney function. Results were limited by unavailability of data from several trials and paucity of enrolled patients with stage 4-5 CKD. Thus, our patient-level meta-analysis of individuals with CKD randomized to CABG versus PCI suggests that CABG significantly reduces the risk of subsequent myocardial infarction and revascularization without affecting survival in these patients.

CKD and coronary collateral supply in individuals undergoing coronary angiography after myocardial infarction.

BACKGROUND AND OBJECTIVES: CKD patients have high mortality risk after myocardial infarction (MI). An adequate supply of coronary collaterals to the culprit vessel responsible for MI is associated with reduced risks of death and complications. Whether a diminished supply of collaterals contributes to the high risk in CKD patients is uncertain. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Quantitative coronary angiography was performed in a consecutive series of individuals with (n=58) and without (n=165) CKD (estimated GFR <60 ml/min per 1.73 m(2)) who underwent coronary angiography at the time of MI. Collateral supply was analyzed and candidate predictors were assessed in patient-level and individual artery-level models using logistic regression and ordered categorical regression, respectively. RESULTS: There were no significant differences in collateral supply among 58 CKD patients and 165 individuals with preserved renal function. Culprit artery collaterals were present in 25.0% of CKD patients compared with 27.2% of individuals with preserved renal function (P=0.76). The odds of having an adequate supply of culprit vessel collaterals were also not significantly different in individuals with and without CKD, respectively. CKD patients were 2.22-fold more likely to have visible collaterals to the nonculprit vessels in unadjusted analyses. The difference was not significant after correction for percent stenosis and comorbid factors. CONCLUSIONS: Our results do not support an independent association between CKD and diminished collateral supply to either the culprit or nonculprit vessels in MI. Additional studies are warranted to better define associations between myocardial capillary supply, collateral supply, and the full range of human CKD.

Early angiography in patients with chronic kidney disease: a collaborative systematic review.

BACKGROUND AND OBJECTIVES: In the general population, an early invasive strategy of routine coronary angiography is superior to a conservative strategy of selective angiography in patients who are admitted with unstable angina or non-ST segment elevation myocardial infarction (MI), but the effectiveness of this strategy in individuals with chronic kidney disease (CKD) is uncertain. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a collaborative meta-analysis with data provided by the main authors of identified trials to estimate the effectiveness of early angiography in patients with CKD. The Cochrane, Medline, and EMBASE databases were searched to identify randomized trials that compared invasive and conservative strategies in patients with unstable angina or non-ST MI. Pooled risks ratios were estimated using data from enrolled patients with estimated GFR <60 ml/min per 1.73 m(2). RESULTS: Five randomized trials that enrolled 1453 patients with CKD were included. An early invasive strategy was associated with nonsignificant reductions in all-cause mortality, nonfatal MI, and a composite of death or nonfatal MI. The invasive strategy significantly reduced rehospitalization. CONCLUSIONS: This collaborative study suggests that the benefits of an early invasive strategy are preserved in patients with CKD and that an early invasive approach reduces the risk for rehospitalization and is associated with trends of reduction in the risk for death and nonfatal re-infarction in patients with CKD. Coronary angiography should be considered for patients who have CKD and are admitted with non-ST elevation acute coronary syndromes.