Frequency and predictors of contrast-induced nephropathy after angioplasty for chronic total occlusions

BackgroundThe incidence and predictors of contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) have not been specifically reported.MethodsThis retrospective analysis included all consecutive patients referred for PCI of CTO between April 2003 and March 2008, with baseline and 24 h postprocedural available creatinine levels. CIN was defined as 24 h postprocedural increase of baseline creatinine levels ≥ 0.5 mg/dl (CIN05) or ≥ 25% (CIN25). Severe renal dysfunction (SRD) was defined as acute renal failure requiring dialysis, or an increase in baseline creatinine levels ≥ 2.0 mg/dl (SRD2) or ≥ 50% (SRD%). Patients were classified into risk categories for CIN, according to the validated Mehran risk score.ResultsA total of 227 patients were included, mean age of 64 ± 10 years, the majority being at low risk for CIN (55% with ≤ 5 points in the Mehran score). CIN25 occurred in 6.16% (14/227) patients and CIN05 in 0.88% (2/227). The incidence of SRD2 or SDR% was 0% (0/227) and 0.9% (2/227), respectively, with no patient requiring dialysis. Patients who developed CIN25 received a higher contrast volume than those who did not (312 ml (210–400) vs 260 ml (200–345), p = 0.14), but the difference was not statistically significant.ConclusionsIn this consecutive cohort of patients, the incidence of CIN following PCI for CTO was low despite the administration of moderate to large volumes of contrast media. Attempts at revascularization of CTO should not be discouraged or be prematurely interrupted because of the fear of CIN.