Changes in renal function and occurrence of contrast-induced nephropathy after percutaneous coronary interventions in patients with atrial fibrillation treated with non-vitamin K oral anticoagulants or warfarin

Introduction
Patients with atrial fibrillation (AF) receiving non-vitamin K oral anticoagulants (NOAC) have a slower decline in renal function than those taking warfarin. Moreover, a warfarin-related nephropathy has been described.

Aim
We assessed variation of estimated glomerular filtration rate (eGFR) and occurrence of contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) in patients with AF taking warfarin compared with NOAC.

Material and methods
We retrospectively enrolled consecutive patients taking oral anticoagulation for AF undergoing PCI. The primary endpoint was variation in eGFR and serum creatinine levels within 48–72 h after PCI. The secondary endpoint was occurrence of CIN, defined as a ≥ 25% relative increase, or a ≥ 0.5 mg/dl absolute increase, in serum creatinine levels within 48–72 h.

Results
We enrolled 420 patients (mean age: 75.0 ±5.5 years, 272 (64.7%) male), 124 (29.5%) treated with NOAC and 296 (70.5%) with warfarin. NOAC patients showed a reduced decline in renal function (eGFR change: –2.8 ±7.9 ml/min/1.73 m² vs. –4.5 ±6.5 ml/min/1.73 m², respectively, p = 0.02) and a smaller increase in serum creatinine levels (0.026 ±0.112 vs. 0.055 ±0.132, p = 0.032) after PCI compared with warfarin. In the multivariate linear regression model independent predictors of eGFR changes were diabetes, baseline eGFR ≤ 60 ml/min/1.73 m² and warfarin use. Occurrence of CIN did not differ between NOAC and warfarin patients (13 (10.5%) vs. 46 (15.5%), p = 0.22).

Conclusions
Patients with AF taking NOAC have a reduced decline in renal function after PCI compared with warfarin. The NOAC may be a reasonable option for patients with a high risk of developing CIN.