Effects of two different treatments with continuous renal replacement therapy in patients with chronic renal dysfunction submitted to coronary invasive procedures

Background: Percutaneous coronary intervention (PCI) requires the use of iodinated contrast medium and consequently poses the risk of contrast-induced nephropathy (CIN), which can negatively impact on outcome. Patients with chronic kidney disease (CKD) are at particularly high risk of CIN. In this study, we investigated the role of continuous renal replacement therapy (CRRT) performed before and after versus only after PCI in patients with CKD. Methods: We studied 46 consecutive patients with CKD (mean creatinine >2 mg/dL) submitted to PCI: 21 (mean creatinine 2.7 ± 1.6 mg/dL) treated with CRRT only after PCI (CRRTpost) and 25 (mean creatinine 3.0 ± 1.3 mg/dL) with CRRT before and after PCI (CRRTpre-post). CRRT was performed with hemofiltration (creatinine 3 mg/dL), initiated 6-8 hours before PCI and re-started immediately post PCI for 18-24 hours. Results: Creatinine showed a greater reduction in CRRTpre-post (2.4 ± 1.0 vs 3.0 ± 1.3 mg/dL; P≤.002) with respect to CRRTpost (2.6 ± 1.3 vs 2.7 ± 1.6 mg/dL; P≤.667). At median 14.7-month follow-up, CKD worsened in 3 patients (12%) of CRRTpre-post and in 9 (43%) of CRRTpost (P≤.042). Kaplan-Meier analysis at 18 months showed a significantly higher overall mortality in patients treated with CRRTpre-post vs CRRTpost (P≤.041), which became even more significant during the entire follow-up period (P≤.026) and an increase in cardiovascular deaths (5 vs 0, respectively). Conclusions: Our results suggest that in CKD patients undergoing PCI, CRRT performed before and after is more effective in preventing a further deterioration of renal function and is associated with an improved long-term outcome when compared to CRRT performed only after.