Impact of Procedure Volume on the Outcomes of Surgical Aortic Valve Replacement

Thorac Cardiovasc Surg. 2024 Apr;72(3):173-180. doi: 10.1055/s-0042-1754352. Epub 2022 Aug 2.

Abstract

Background: Literature demonstrated that procedure volumes affect outcomes of patients undergoing transcatheter aortic valve implantation. We evaluated the outcomes of surgical aortic valve replacement.

Methods: All isolated surgical aortic valve replacement procedures in Germany in 2017 were identified. Hospitals were divided into five groups from ≤25 (very low volume) until >100 (very high volume) annual procedures.

Results: In 2017, 5,533 patients underwent isolated surgical aortic valve replacement. All groups were of comparable risk (logistic EuroSCORE, 5.12-4.80%) and age (66.6-68.1 years). In-hospital mortality and complication rates were lowest in the very high-volume group. Multivariable logistic regression analyses showed no significant volume-outcome relationship for in-hospital mortality, stroke, postoperative delirium, and mechanical ventilation > 48 hours. Regarding acute kidney injury, patients in the very high-volume group were at lower risk than those in the very low volume group (odds ratio [OR] = 0.53, p = 0.04). Risk factors for in-hospital mortality were previous cardiac surgery (OR = 5.75, p < 0.001), high-grade renal disease (glomerular filtration rate < 15 mL/min, OR = 5.61, p = 0.002), surgery in emergency cases (OR = 2.71, p = 0.002), and higher grade heart failure (NYHA [New York Heart Association] III/IV; OR = 1.80, p = 0.02). Risk factors for all four complication rates were atrial fibrillation and diabetes mellitus.

Conclusion: Patients treated in very low volume centers (≤25 operations/year) had a similar risk regarding in-hospital mortality and most complications compared with very high-volume centers (>100 operations/year). Only in the case of acute kidney injury, very high-volume centers showed better outcomes than very low volume centers. Therefore, surgical aortic valve replacement can be performed safely independent of case volume.

MeSH terms

  • Acute Kidney Injury* / etiology
  • Aged
  • Aortic Valve / diagnostic imaging
  • Aortic Valve / surgery
  • Aortic Valve Stenosis* / diagnostic imaging
  • Aortic Valve Stenosis* / surgery
  • Heart Valve Prosthesis Implantation*
  • Hospital Mortality
  • Humans
  • Risk Factors
  • Transcatheter Aortic Valve Replacement*
  • Treatment Outcome