Project Summary/Abstract
Approximately 12.4% of patients >75 years of age have aortic stenosis (AS) and 3.4% have severe AS.
Transcatheter aortic valve replacement (TAVR) has emerged as a safe and effective therapeutic option for
patients with symptomatic severe AS. More than 50,000 TAVRs are now performed annually across >500
hospitals in the United States (US). Despite stringent patient selection criteria and standardized procedural
techniques, there remains significant hospital variation in outcomes, including mortality, morbidity, and
readmissions, following TAVR in the US. However, the reasons underlying hospital variation in TAVR
outcomes remain poorly understood. Identifying organizational practices and processes of care associated with
better outcomes is critical to improve the overall outcomes of patients undergoing TAVR. The overarching
objective of this proposal is to perform a mixed methods study using a positive deviance approach to
understand determinants of hospital variation in TAVR outcomes and to identify modifiable practices
associated with improved outcomes. In Aim 1, we will use data from the Transcatheter Valve Therapy Registry
to identify high- and low-performing TAVR hospitals based on variation in two key patient-centered outcomes
after TAVR – 30-day major adverse events (MAE, defined as a global ranked composite of mortality, stroke,
major/life-threatening bleeding, acute kidney injury stage 3, and moderate/severe paravalvular leak) and 30-
day readmissions. In Aim 2, we will conduct in-depth, semi-structured interviews of key clinical and
administrative staff involved in the care of TAVR patients in a representative sample of high- and low-
performing hospitals. The qualitative data will be analyzed to identify specific themes associated with high
performance, and to develop two distinct conceptual models of factors influencing MAE and readmissions,
respectively, after TAVR. This study will identify ‘best practices’ that can be adopted by low-performing and
new TAVR programs to improve their patient outcomes. Further, this research has the potential to identify clear
evidence-based structure and process measures that can inform guidelines and policies on evaluation of the
quality of TAVR and other transcatheter valve intervention programs. This research will be accomplished in the
setting of a comprehensive career development plan designed to provide Dr. Kolte, an early career
investigator, with the training and skills necessary to achieve his long-term career goal of becoming an
independent clinician-investigator with expertise in cardiovascular outcomes and mixed methods research in
the field of transcatheter heart valve interventions. An outstanding mentoring team and scientific advisory
committee of established investigators in the fields of valvular heart disease, outcomes research, quantitative
methods, and qualitative/mixed methods research will guide Dr. Kolte in his transition to independence over
the course of the award period.