Abstract 2140: Overestimation of Systolic Dyssynchrony Index with Real-time Three-dimensional Echocardiography by Inadequate Image Planes
Introduction: Real-time three-dimensional (RT3D) echocardiography can quantify global mechanical dyssynchrony in patients with heart failure (HF) by calculating the systolic dyssynchrony index (SDI). The influence of the number of image planes in endocardial border tracing on the accuracy of the measurement of SDI has not been studied both in normal subjects and in patients with HF. We assessed the hypothesis that the accuracy of SDI was affected by the number of image planes required to preserve adequate sampling in RT3D dyssynchrony analysis.
Methods: 26 normal subjects (50 ± 12 years) and 20 patients with HF (60 ± 14 years) were imaged by RT3D echocardiography and data were analyzed offline by two blinded, independent observers. SDI was determined using 2, 4, 8, 12 and 32 equidistant image planes for endocardial border tracing. Data in normal subjects and patients with HF from 2, 4, 8, 12-plane images were compared to that from 32-plane images and repeat measurements.
Results: SDI was significantly higher in patients with HF than that in normal subjects (11.8 ± 7.2 vs. 4.7 ± 1.6, p<0.001). Biplane and 4-plane assessment usually overestimate the value of SDI. Eight-plane views are accurate and efficient to gain accurate results both in normal subjects and patients with HF.
Conclusions: Accurate quantification of RT3D mechanical dyssynchrony can be obtained from 8 image planes both in normal subjects and patients with HF.