Energy Loss Index as a Predictor of All-Cause Mortality after
Transcatheter Aortic Valve Replacement: A 9-year follow-up
Abstract
Background: As transcatheter aortic valve replacement (TAVR)
procedures become more widely available, there is a growing need to
monitor and evaluate postoperative outcomes accurately. The energy loss
index (ELI) of the ascending aorta has been commonly used to examine the
agreement between the echocardiographic and Gorlin measurement of the
aortic valve area. Objectives: This project aims to demonstrate
a link between ELI values and mortality following implanted TAVR valves
and determine an ELI cutoff value associated with post-TAVR events.
Method: We retrospectively reviewed patients undergoing TAVR
from 2012 – 2017. We calculated ELI values for patients immediately
postoperative after a TAVR procedure. Using Receiver-Operator
Characteristic and Cox Regression analyses, we identified a cutoff value
to distinguish between high and low-risk patients. Results:
This study showed ELI ≤ 1.34 (hazard ratio, 1.783; 95% confidence
interval 1.231-2.583, p=0.002) as representative of patients with a high
risk of mortality post-TAVR. Additionally, post-TAVR, ejection fraction
increased by 3.5 percent (p<0.001), and the aortic valve
effective orifice area increased by 1.25 cm squared (p<0.001)
while the mean transvalvular gradient decreased by 33.6 mmHg
(p<0.001) and the peak transvalvular gradient decreased by
49.7 mmHg (p<0.001). Conclusion: ELI is an additional
prognostic factor that should be considered during risk assessment
before TAVR. This study shows that patients with ELI ≤ 1.34 had
decreased cumulative survival post-TAVR. These patients had a fivefold
increased risk of death following TAVR.