Objectives: To evaluate the change in utilization of TTEs associated with introduction of limited LVEF TTEs.
Methods: We measured the number of total, full and limited TTEs before (2005) and after (2006-2015) implementation of limited LVEF TTEs at the Palo Alto VA Hospital (PAVA) and compared to other VA hospitals. We estimated the association between introduction of the LVEF TTEs at PAVA and TTEs volume using a linear regression model with other facilities as controls adjusted for facility, number of outpatients and average patient age.
Results: There were 119 VA facilities that performed over 100 TTEs in 2005. Between PAVA and 118 control VA facilities, there was no significant difference in the number of outpatients (52,654 vs. 44,552 +/- 25,342[SD], p=0.37), average age (61.4 vs. 61.8 years +/- 2.5, p=0.44) total TTEs in 2005 (2,395 vs. 1,594.8 +/- 1,069.6, p=0.23) or limited TTEs (19 vs. 25.8 +/-101.5, p=0.48) in 2005. In 2005, limited TTEs were 0.8% of all TTEs at PAVA and 1.2% at controls. Between 2006-2010, limited TTEs were 8.3% of total at PAVA and 1.7% at controls. Between 2011-2015, limited TTEs were 19.5% of total at PAVA and 2.2% at controls. In 2005, total TTEs per outpatient were 4.5 per 100 at PAVA and 3.5 per 100 at other VA hospitals. Between 2006-2010, total TTEs were 4.5 per 100 patient-years at PAVA and 3.9 per 100 patient-years at controls. Between 2011-2015, total TTEs per capita were 4.6 per 100 patient-years at PAVA and 4.3 per 100 patient-years at controls. In an adjusted model, limited LVEF TTE introduction was associated with an average of -383 (CI: -554 to -211) annual full TTEs with no significant difference in total TTEs (-26.8; CI: -156 to 102). The decrease in full TTEs increased each year with an estimated -67.0 (CI: -97 to -37) full TTEs per year after 2006. This was equivalent to 683 fewer full TTEs (30.0% of total) in 2015.
Conclusion: The introduction of limited LVEF TTEs at PAVA was associated with an increase in limited TTEs, a decrease in full TTEs, and no significant change in total TTEs when compared with control facilities. This suggests the introduction of LVEF studies was associated with substitution of limited TTEs for full studies. This could lead to substantial reductions in resource utilization and costs. We did not evaluate potential changes in outcomes associated with this change in TTE utilization.