Zero-contrast cardiac resynchronization therapy device implantation in heart failure patients with renal impairment

BACKGROUND: Coronary sinus (CS) venography is commonly used during cardiac resynchronization therapy (CRT) to guide left ventricular lead placement; however, iodinated contrast poses a substantial risk of contrast-induced acute kidney injury (CI-AKI) in patients with chronic kidney disease (CKD).Evidence supporting contrast-sparing CRT techniques remains limited. OBJECTIVE:To assess the feasibility, safety, and renal outcomes of a zero-contrast CRT implantation strategy in CKD patients. METHODS:Consecutive CKD patients (estimated glomerular filtration rate eGFR <60 mL/min/1.73m) undergoing CRT at two centers between January 2023 and June 2025 were analyzed.Procedures were initiated using a contrast-free approach, with CS venography reserved as a bail-out strategy.Predictors of 20% eGFR decline were evaluated using multivariable logistic regression.Secondary outcomes included increase in left ventricular ejection fraction (LVEF) 5 percentage points at 3-6 months and one-year allcause mortality and heart failure hospitalization (HFH). RESULTS:Overall, 113 patients were analyzed.Zero-contrast implantation was successful in 57.5% of cases.Renal function remained stable after zero-contrast implantation (eGFR +3.6 mL/min/1.73m; p = 0.08), whereas it declined significantly in the contrast group (-7.9 mL/min/1.73m; p < 0.001).Postprocedural AKI occurred in 1.5% versus 14.6% of patients, respectively (p = 0.004).Contrast use (odds ratio 6.8, 95% confidence interval 1.5-30.9;p = 0.013), lower baseline eGFR, and diabetes independently predicted a 20% decline in eGFR.Complication rates, LVEF improvement, and one-year mortality or HFH were similar between groups.CONCLUSION: Zero-contrast CRT implantation is feasible, safe, and effective, with better renal preservation in patients with CKD.