Impact of Transcatheter Aortic Valve Replacement Volume on Outcomes in Patients with End Stage Renal Disease

E. Aguayo¹, O. Kwon², N. Le³, S. Mallick², T. Coaston⁴, K. Tabibian, BS², J. E. Hadaya⁵, Y. Sanaiha⁵, R. Shemin², P. Benharash^6
1Harbor UCLA, Torrance, California ²UCLA, Los Angeles, California ³David Geffen School of Medicine at UCLA, Tarzana, California ⁴David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California ⁵David Geffen School of Medicine at UCLA, Los Angeles, California ⁶UCLA Division of Cardiac Surgery, Los Angeles, California

Purpose: Patients with end-stage renal disease (ESRD) are at increased risk of developing premature calcific aortic stenosis. Given limited data on the efficacy of transcatheter aortic valve replacement (TAVR) in this population, the present study examined acute mortality, complications and 30-day nonelective readmissions in a national cohort of patients with ESRD.

Methods: The 2016-2021 National Readmissions Database was queried to identify all adult (≥18 years) admissions entailing TAVR. Patients were grouped into ESRD and nonESRD using previously reported International Classification of Diseases-10th Revision (ICD-10) codes for ESRD: N18.6, Z99.2, Z91.15. The primary endpoints were mortality during index hospitalization and 30-day non-elective readmission. Secondary outcomes included postoperative complications (neurologic, cardiac, respiratory, thrombotic and infectious), duration of stay, and total hospitalization costs. Multivariable logistic regression was used to identify factors associated with mortality and readmission. Additionally, Nelson-Aalen cumulative hazard analysis was performed to evaluate the cumulative risk of readmission within 180 days of discharge while accounting for institutional TAVR volume quartiles. Low- (LVH) and High-Volume Hospitals (HVH) were defined as those within the bottom and top 25% of annual caseload, respectively.

Results: Of an estimated 411,311 patients receiving TAVR, 7.3% had preexisting ESRD. Compared to LVH, centers with the highest quartile of TAVR volume were most likely to perform TAVR on ESRD patients (HVH: 61.4% vs LVH: 1.9%). Compared to nonESRD, patients with ESRD were younger (78 [70-84] vs 80 [74-85]) years) and had a greater burden of comorbidities, including congestive heart failure, coronary artery disease, and diabetes (all P< 0.001) (Table). On bivariate analysis, ESRD experienced increased in-hospital mortality (3.1% vs 1.2%) and 30-day readmission (20.8% vs 10.1%) (both P< 0.001). There was no significant change in readmission rates in ESRD patients during the study period (P=0.20). Readmission rates in nonESRD patients improved during the study period (P < 0.001). After multivariable adjustment, the presence of ESRD remained associated with increased odds of in-hospital mortality (AOR 1.79, 95% CI [1.60-2.00]) (Figure1A) and 30-day readmission (AOR 1.86, 95% CI [1.78-1.95]) (Figure1B). Nelson-Aalen cumulative hazard analysis demonstrated a significantly higher cumulative risk of readmission for ESRD when compared to nonESRD (Figure1C). Highest institutional TAVR volume did not improve readmission rates for ESRD but did improve readmission rates for nonESRD (Figure1C).

Conclusion: Patients with ESRD are at increased risk for postoperative mortality, hospital resource utilization, and readmissions. When adjusting for TAVR volume, high volume centers exhibit increased readmission rates in ESRD patients. Given the increased risk of mortality and readmission, careful patient selection and optimization is crucial for ESRD patients undergoing TAVR.

Identify the source of the funding for this research project: None