Background and method: We evaluated a new method of shape analysis in defining right ventricle (RV) response to pressure overload. Twenty-five neonatal patients (13 with RV hypertension, 12 without) underwent echocardiographic imaging and reconstruction of RV regional chamber volumes over 1 cardiac cycle. Group tracing data in coronal, sagittal, and transverse echocardiography planes were then shape-averaged to construct normal- and hypertensive-average-shape contraction models. Each patient's RV was classified as more similar to the normal- or hypertensive-average-shape model on the basis of the median tangent-angle difference, a quantitative technique of shape comparison.
Results: Ejection fraction, time of end systole, and ejection rate demonstrated significant regional differences between normotensive and hypertensive contractions. The normal-average-shape contraction model correctly diagnosed all patients who were normotensive (specificity 100%) and the hypertensive-average-shape model identified 11 of 13 patients who were hypertensive (sensitivity 85%).
Conclusion: Reconstructed-shape contraction models throughout 1 cardiac cycle identify altered patterns of RV contraction in the presence of pulmonary hypertension.