Impact of Preoperative Chronic Kidney Disease in 2,531 High-Risk and Inoperable Patients Undergoing Transcatheter Aortic Valve Replacement in the PARTNER Trial

Background: Although preoperative renal dysfunction (RD) is associated with increased mortality and morbidity after surgical aortic valve replacement, its impact on clinical outcomes after transcatheter aortic valve replacement (TAVR) is less defined.

Methods: TAVR patients in the PARTNER (Placement of Aortic Transcatheter Valves) trial with a calculable glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease equation were included. Patients were divided into three groups: GFR >60 mL/min (none/mild RD), GFR 31 to 60 mL/min (moderate RD), and GFR ≤30 mL/min (severe RD). Operative characteristics and clinical outcomes were analyzed. Cox regression models were used to determine multivariable predictors of 1-year all-cause mortality.

Results: A total of 2,531 inoperable or high surgical risk patients from the PARTNER trial and continued access registries had a calculable GFR level: 767 (30%) had normal renal function or mild RD, 1,473 (58%) had moderate RD, and 291 (12%) presented with severe RD. The mean Society of Thoracic Surgeons Predicted Risk of Mortality for the cohort was 11.5%, and it was highest in those with severe RD (13.8%). Patients with severe RD were more often women with a higher prevalence of diabetes. Patients with severe RD had the highest incidence of 30-day and 1-year all-cause mortality and rehospitalization. The 30-day rate of death from any cause was 10.7% in the severe RD group versus 6.0% in the moderate and mild RD groups (p = 0.01). The 1-year rate of death from any cause was 34.4% in the severe RD group versus 21.5% in the moderate RD and 20.8% in the none/mild RD groups (adjusted hazard ratio [HR] 2.24, p < 0.0001 for severe versus none/mild; adjusted HR 1.14, p = 0.24 for severe versus moderate). Other significant predictors of 1-year all-cause mortality included lower body mass index, frailty, the transapical approach, a lower ejection fraction, oxygen-dependent chronic obstructive pulmonary disease, liver disease, and male sex.

Conclusions: Preoperative severe RD is a significant predictor for 1-year mortality in TAVR patients. Careful risk stratification by the heart team is required in patients with severe preprocedural RD.