403 Relevance of quantitative exercice Doppler echocardiography in asymptomatic valvular aortic stenosis versus bicycle exercice-stress-test

Abstract

s S55 Eur J Echocardiography Abstracts Supplement, December 2006 analysed by 2 separate observers. TOE and RT-3DE images were acquired digitally on the Phillips IE33 ultrasound machine and stored for off line analysis. The RT-3DE datasets were analysed with Phillips Qlab software (version 4.0). Leaflet segments and commissures were displayed in short axis en-face and long axis views. Echocardiographic results were validated intraoperatively. Results: Five patients did not have image quality suitable for analysis with RT-3DE and were excluded from analysis. This left a sample size of 39 patients (mean age 52±11 years, 19 male). Twenty five patients had mitral valve repair and 9 mitral valve replacement. In total, 54 out of 334 analysed mitral valve segments were diseased. Prolapse of a single mitral valve segment was present in 25 patients. 14 patients had complex disease involving 2 or more segments. Sensitivity, specificity and accuracy for TOE in identification of diseased segments were 94%, 100% and 96% respectively. The same values for RT-3DE were 91%, 100%, 94%. The differences were not statistically significant. Accuracies were not significantly different according to segment location. Ruptured chordae was confirmed at surgery in 20 patients. Sensitivity for the diagnosis of ruptured chordae was 90% for TOE and 72% for RT-3DE (p=0.03). Specificity was comparable by both techniques (89% TOE vs 83% RT-3DE). Interobserver agreement was 92% (for TOE (k=0.85) and 86% for RT-3DE (k=0.83, p=non significant). The mean procedure time for TOE was 27±6 minutes. This was significantly longer than the procedure time for RT-3DE (7±3 minutes, p=0.03). The mean 3D reconstruction time was 15±8 minutes. Conclusions: RT-3DE is feasible with comparative accuracy to TOE for precise anatomical localisation of prolapsing mitral valve segments. However, the technique is limited by poor image quality in a small proportion of patients. TOE remains superior for diagnosis and localisation of chordal rupture.