Background: Patients with moderate chronic renal failure have recently been identified to suffer from a markedly higher mortality after percutaneous coronary intervention (PCI). We focused on the outcome of PCI patients with just mildly elevated creatinine levels of 1.1 to 1.5 mg/dL.
Methods: Data of all PCI patients of the years 1998 to 1999 were analyzed. Follow-up was performed by a questionnaire sent to all patients.
Results: During this period, PCI was performed in 1049 patients. Long-term follow-up (1184 +/- 10 days) was 99.6% complete. Total mortality increased continuously by each creatinine increment of 0.1 mg/dL above 1.0 mg/dL, with a significant difference at 1.3 mg/dL compared to patients with <or=1.0 mg/dL (12.4 vs. 5.5%, P < 0.05). In a Kaplan-Meier model, patients with a creatinine of 1.3 to 1.4 mg/dL had a significantly lower cumulative survival after three years (87%) than controls (96%, P = 0.0108, log rank test). Higher serum creatinine levels were found to be significantly associated with death in univariate analysis (1.1 +/- 0.4 vs. 1.5 +/- 1.0 mg/dL, P < 0.00001), and in multivariate analysis by stepwise logistic regression (OR 2.122, 95% CI 1.585 to 2.841).
Conclusions: In this retrospective cross-sectional study, even patients with slightly elevated serum creatinine levels of 1.3 to 1.4 mg/dL had a significantly reduced long-term outcome after PCI. Thus, even mild chronic renal failure appears to be associated with markedly increased risk after a PCI, with implications to the high number of patients concerned.