Abstract 10613: Impact of a New Index of Patient-Prosthesis Mismatch, Energy Loss Index, on Left Ventricular Mass Regression after Aortic Valve Replacement

Abstract

Background: Patient-prosthesis mismatch (PPM) is a clinical issue in patient after aortic valve replacement (AVR). In patients with PPM, less left ventricular (LV) mass regression was observed after AVR than those without PPM. Recently, energy loss coefficient index (ELI), has been proposed as a non-invasive and functional index to assess severity of aortic stenosis (AS).

Purpose: The purpose of this study was to investigate the impact of ELI on LV mass regression in patients who underwent AVR with mechanical valves.

Methods: A total of 16 patients with severe AS who underwent AVR with mechanical valves were enrolled and examined. Echocardiography was performed immediately after AVR and repeated 12 months later. ELI was calculated as [effective orifice area (EOA) x aortic cross sectional area] / (aortic cross sectional area - EOA) divided by body surface area. EOA was derived from previously reported normal EOA value for each prosthetic valve. Relative LV mass regression (%) was calculated as 100 x (LV mass at follow-up - LV mass at baseline) / (LV mass at baseline).

Results: During follow up, LV mass regressed significantly (243.6±93.8 to 171.3±66.5 g, P<0.01). A mean value of relative LV mass regression was 28.9 %. Relative LV mass regression correlated well with ELI (r=0.71, P<0.01). By receiver operating characteristics analysis, ELI < 1.06 cm²/m² predicts smaller (< 28.9%) relative LV mass regression after AVR with a sensitivity of 100% and a specificity of 77.8%.

Conclusions: ELI predicts LV mass regression after AVR with mechanical valves. ELI may be used as an index to assess PPM.