Study: ARF Risk Greater with CABG
Giora Weisz, MD
The results, from a subanalysis of the Acute Catheterization and Urgent Intervention Triage strategy (ACUITY) trial, were presented here at the 58th Annual Scientific Session of the American College of Cardiology by Giora Weisz, MD, Director of Research at the Center for Interventional Vascular Therapy, Columbia University Medical Center, New York City.
“In patients requiring revascularization, concerns about contrast-induced nephropathy often lead to referral for CABG over PCI,” Dr. Weisz said. The new findings, however, suggest this may not be wise.
The ACUITY trial examined the effect of revascularization mode (PCI vs. CABG) on the rate of in-hospital ARF in 13,819 patients with acute coronary syndromes. Patients underwent angiography within 72 hours of admission and then were triaged to PCI (7,789 patients), CABG (1,539 patients), or medical management (4,491 patients). Serum creatinine (SCr) was measured throughout the hospital stay. The investigators defined ARF as an SCr increase of 25% or more or 0.5 mg/dL or more from baseline.
The groups had some differences at baseline. Patients who underwent CABG tended to be older and were more likely to have diabetes, elevated cardiac biomarkers, ST-segment deviations, and lower ejection fractions.
Compared with the PCI group, CABG patients had more triple-vessel disease, greater extent of disease, and more lesions per patient and per vessel. More patients in the PCI group had hyperlipidemia, and they were more likely to have had a previous MI, angioplasty, or CABG.
Regarding baseline renal function for the two groups, mean SCr was 1.0 mg/dL in each group and baseline renal insufficiency was observed in 18% of each group. Mean creatinine clearance was different, however: 88.10 mL/min in the PCI group compared with 84.05 mL/min/ in the CABG group.
After revascularization, ARF developed in 32.2% of patients undergoing CABG compared with only 11.6% undergoing PCI, which is almost threefold increased risk of ARF with CABG compared with PCI, Dr. Weisz reported.
Other significant predictors of renal status post revascularization included diabetes, which increased the risk of ARF by 38%; ST-segment deviation greater than 1 mm, which increased the risk by 27%; and male gender, which decreased the risk by 44%.
Dr. Weisz acknowledged some study limitations. For example, he noted that the study was a retrospective subgroup analysis without randomization to revascularization mode.
Additionally, the groups were not completely balanced at baseline. CABG patients were older and had more comorbidities (including diabetes) and more extensive coronary artery disease. Moreover, SCr data between the angiogram and surgery were lacking for the CABG group, he said.
Nevertheless, Dr. Weisz said the magnitude of the difference in risk is noteworthy. “When considering the mode of revascularization in patients with coronary artery disease,” he said, “the significantly increased risk of acute renal failure with CABG should be considered.”