Effect of the Mehran risk score for the prediction of clinical outcomes after percutaneous coronary intervention.

Background: The association of Mehran risk score (MRS) with long-term prognosis in patients treated with percutaneous coronary intervention (PCI) has not been fully reported. We investigated the association between MRS and clinical outcomes in patients who underwent PCI.

Methods: Study subjects comprised 2198 patients treated with PCI from the Ibaraki Cardiovascular Assessment Study multicenter registry, excluding patients receiving hemodialysis or who died within 7 days. We categorized them into 4 groups according to MRS (low-risk: ≤5; medium-risk: 6-10; high-risk: 11-16; and very high-risk: ≥16). Contrast-induced acute kidney injury (CI-AKI) was defined as an increase of 0.5mg/dL or 25% in pre-PCI serum creatinine within 1-week post procedure. We evaluated CI-AKI and major adverse cardiac and cerebrovascular events (MACCE), and defined as all-cause death, myocardial infarction, congestive heart failure, or cerebrovascular disorder (stroke or transient ischemic attack).

Results: A total of 192 (8.7%) patients developed CI-AKI. At multivariate analysis, odds ratio for CI-AKI was 4.09 (95% CI: 1.72-9.17, p=0.002) in the very high-risk group, 1.49 (95% CI: 0.89-2.42, p=0.120) in the high-risk group, and 1.08 (95% CI: 0.74-1.54, p=0.693) in the medium-risk group, as compared with the low-risk group. MACCE in the very high-risk group was more than 5-fold higher [hazard ratio (HR) 5.40, 95% CI: 2.96-9.28, p<0.001] compared with the low-risk group and was also increased in the high-risk (HR 3.72, CI: 2.59-5.32, p<0.001) and medium-risk groups (HR 1.97, CI: 1.45-2.69, p<0.001). Kaplan-Meier analysis showed that increasing risk for MACCE was seen across the groups as MRS increased (p<0.001).

Conclusion: MRS might provide potentially useful information for prediction of CI-AKI and clinical outcomes after PCI.