Reduced variability of visual left ventricular ejection fraction assessment with reference images: The Japanese Association of Young Echocardiography Fellows multicenter study.

BACKGROUND: Visual estimation of left ventricular ejection fraction (LVEF) is widely applied to confirm quantitative EF. However, visual assessment is subjective, and variability may be influenced by observer experience. We hypothesized that a learning session might reduce the misclassification rate. METHODS: Protocol 1: Visual LVEFs for 30 cases were measured by 79 readers from 13 cardiovascular tertiary care centers. Readers were divided into 3 groups by their experience: limited (1-5 years, n=28), intermediate (6-11 years, n=26), and highly experienced (12-years, n=25). Protocol 2: All readers were randomized to assess the effect of a learning session with reference images only or feedback plus reference images. After the session, 20 new cases were shown to all readers following the same methodology. To assess the concordance and accuracy pre- and post-intervention, each visual LVEF measurement was compared to overall average values as a reference. RESULTS: Experience affected the concordance in visual EF values among the readers. Groups with intermediate and high experience showed significantly better mean difference (MD), standard deviation (SD), and coefficient of variation (CV) than those with limited experience at baseline. The learning session with reference image reduced the MD, SD, and CV in readers with limited experience. The learning session with reference images plus feedback also reduced proportional bias. Importantly, the misclassification rate for mid-range EF cases was reduced regardless of experience. CONCLUSION: This large multicenter study suggested that a simple learning session with reference images can successfully reduce the misclassification rate for LVEF assessment.

The Speckle Tracking Imaging for the Assessment of Cardiac Resynchronization Therapy (START) study.

BACKGROUND: We sought to identify the feasibility of speckle tracking echocardiography (STE) to predict cardiac resynchronization therapy (CRT) responders in a prospective multicenter study. METHODS AND RESULTS: Patients who were newly implanted with a CRT device were enrolled. Time (T) from QRS to maximum peak radial and circumferential strain (CS) in 6 segments on the left ventricular (LV) short-axis plane, and to the maximum peak of longitudinal strain in 18 segments on 3 apical LV planes was measured (Tmax). In segments with multiple peaks on the time-strain curves, time to the first peak (Tfirst) was also assessed. Difference in T between the earliest and latest segment and standard deviation (SD) of T in each strain component were assessed. CRT responders were defined as having LV end-systolic volume reduction >15% at 6 months after CRT. Clinical outcomes were assessed with a composite endpoint of death from cardiac causes or unplanned hospitalization for heart failure. Among 180 patients, 109 patients were identified as responders. Tfirst-SD of CS >116 ms was selected as the best independent predictor of CRT responders (P<0.001, hazard ratio=9.83, 95% confidence interval 3.78-25.6). In addition, Tfirst-SD of CS was associated with the clinical endpoints. CONCLUSIONS: This prospective multicenter study revealed the high feasibility of dyssynchrony assessment by STE, which may improve the ability to predict CRT responders.

Significance of echocardiographic assessment for right ventricular function after balloon pulmonary angioplasty in patients with chronic thromboembolic induced pulmonary hypertension.

Balloon pulmonary angioplasty (BPA) may improve hemodynamics and exercise tolerance in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We studied consecutive 25 patients with CTEPH who underwent BPA and evaluated hemodynamics by right-sided heart catheterization. Right ventricular (RV) function was assessed before and after BPA by echocardiography including speckle-tracking echocardiography and 3-dimensional echocardiography. BPA improved the mean pulmonary artery pressure, pulmonary vascular resistance, and cardiac index. BPA also ameliorated the 3-dimentional RV volume, RV ejection fraction, and RV systolic peak strain, all of which were significantly correlated with hemodynamic parameters. The changes in cardiac index were significantly correlated with those in 3-dimentional RV volume index. Furthermore, RV dyssynchrony quantified by the RV strain analyses was ameliorated after BPA even in patients with mild pulmonary hypertension, implicating the merit of BPA in this patient population with CTEPH. BPA not only improved the hemodynamics in patients with CTEPH, but also ameliorated RV remodeling and dyssynchrony as assessed by 3-dimensional echocardiography or speckle-tracking echocardiography. Thus, the assessment of RV function may provide valuable information about the appropriate indication for BPA, its efficacy, and the therapeutic goal for patients with CTEPH.