Learning Curve Characteristics and Relationship of Procedural Volumes with Clinical Outcomes for Transcatheter Aortic Valve Implantation



Transcatheter aortic valve replacement (TAVR) has experienced marked growth in utilization after successful outcome of large randomized trails confirming clinical utility of TAVR for patients at high and intermediate risk for surgical aortic valve replacement (SAVR). However, TAVR remains a complex procedure requiring specific skills and experience for successful outcome. In this chapter, we review the TAVR learning curve and the relationship between institutional or operator volumes with TAVR outcomes. Multiple studies have demonstrated that the measures of process such as procedure time, fluoroscopy time, and contrast use improve significantly with increasing TAVR experience. Similarly, improvement in clinical outcomes has been shown with increasing TAVR experience. The data from PARTNER trial found 80% device success rate after the first 22 cases and reduction in major vascular complications to <5% after the 70 cases. Data from the international TAVR registry showed higher device success and lower rates of valve embolization, paravalvular leak, and mortality for procedures performed in the 4th quartile compared to the first quartile of TAVR experience. In an analysis of >42000 TAVR procedures (US TVT registry), results showed gradual reduction in adverse events from the first case to the 400th case including vascular complications (6.1% vs. 4.2%), bleeding (9.6% vs. 5.1%), and 30-day mortality (3.6% vs. 2.6%). Data from US National Inpatient Sample found an important correlation between clinical outcome and hospital volumes with higher all-cause mortality, bleeding, and pacemaker implantation for low-volume compared to high-volume TAVR centers. In summary, the available data consistently shows that both a learning curve phenomenon and a volume-outcome relationship exist for TAVR procedures. However, TAVR is an evolving field with better device designs, accumulating knowledgebase and advances in care that may impact both the procedural success and clinical outcomes. In addition, it remains to be seen if new centers implanting contemporary TAVR devices with formal mentorship arrangements can shorten learning curve and achieve clinical outcomes comparable to high-volume centers.


Aortic stenosis Transcatheter aortic valve replacement Learning curve Complications Procedural volumes 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Cardiac Catheterization LaboratorySt. Mary’s General HospitalKitchenerCanada
  2. 2.Division of CardiologySt. Michael’s HospitalTorontoCanada

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