TAVR may improve kidney function in patients with aortic stenosis

Patients with severe aortic stenosis who undergo transcatheter aortic valve replacement (TAVR), even with baseline impaired estimated glomerular filtration rate (eGFR), are more likely to improve or maintain their chronic kidney disease (CKD) stage rather than make it worse, a study has shown.

“The effect of TAVR on kidney function stage in patients with aortic stenosis remains poorly understood,” the authors said. “We hypothesized that in some patients, TAVR results in improved kidney function by alleviating cardiorenal syndrome.”

To test this hypothesis, a total of 5,190 patients receiving TAVR in the Placement of Aortic Transcatheter Valves (PARTNER) 1, 2, and PARTNER 2 S3 trials between April 2007 and October 2014 were analysed. The authors evaluated pre-TAVR and procedural variables associated with post-TAVR eGFR, change in CKD stage at ≤7 days post-TAVR, and association of post-TAVR eGFR on intermediate-term mortality.

Of the patients, 91 percent presented with CKD stage ≥2 at baseline. CKD stage either improved or remained unchanged after TAVR in most patients (stage 1: 77 percent; stage 2: 90 percent; stage 3A: 89 percent; stage 3B: 94 percent; stage 4: 99 percent). Only one (0.035 percent) of 2,892 patients progressed to CKD stage 5 within 7 days following TAVR.

Seventy (2.0 percent) of 3,546 patients in whom data were available underwent post-TAVR dialysis. Higher pre-TAVR eGFR and transfemoral approach showed a robust association with higher post-TAVR eGFR. Moreover, lower baseline and longitudinal post-TAVR eGFR correlated with lower intermediate-term survival.

“Aortic stenosis may contribute to cardiorenal syndrome that improves with TAVR,” the authors said.