Adoption and Diffusion of Medical Technology: Evidence from TAVR

New health care technologies have substantially improved health outcomes but have also been implicated in the growing cost of care delivery. The adoption of new technologies itself is a learning process, with evidence showing that new technologies and procedures often involve physician learning and tradeoffs in quality and productivity as clinicians move from older to newer procedures. We consider the early years of uptake for a new cardiac procedure – transcatheter aortic valve replacement (TAVR) – and its implications for physician procedure mix and patient outcomes.

TAVR is a therapy for cardiac patients with severe aortic stenosis who either are not clear candidates for the use of the more invasive, incumbent technology – surgical aortic valve replacement (SAVR) – or who are at high risk for complications due to surgery. In its first three years, TAVR grew to include over 1/3 of all aortic valve replacement procedures in New York State, which serves as the setting for our empirical analysis. We use data on all aortic valve replacement procedures performed in the state of New York over the four-year period (2010-2013, inclusive). Our period of observation precedes the introduction of TAVR spans the early years of its diffusion. We document patterns in the uptake of TAVR across physicians and hospitals as well as patterns of access and receipt among (potential) patients. We ask whether the uptake of TAVR is correlated with prior utilization of SAVR at the physician and/or facility level.

We find that a hospital's pre-TAVR level of specialization in SAVR positively predicts both TAVR adoption and intensity of use. That is, hospitals that had already specialized in aortic valve replacement procedures are more likely to adopt TAVR and use the procedure more frequently when they do. Additionally, a higher fraction of doctors with (any) TAVR experience positively predicts subsequent intensity of use at the hospital level. We also observe meaningfully shorter post-procedure length of stay in hospital following TAVR relative to SAVR. Differences in 30-day mortality post procedure for the two technologies, however, are difficult to discern. The insights from this project are relevant for a broader understanding of the impact of technology diffusion on physician treatment decisions, the accumulation of technology-specific experience at the physician level, patient access to therapies, and health care productivity.