From 2D to 4D in quantitative left ventricle wall motion analysis of biplanar X-ray angiograms

Accurate assessment of regional myocardial function after infarction is a challenging task in biplanar X-ray cine-angiography. An estimate of motion is given by tracking contours of the left ventricle (LV) in projection images. In conventional clinical practice, LV wall motion analysis is done in 2D, based on end-diastolic and end-systolic contours. Our work, by contrast, presents novel methods for analyzing left ventricular motion in 4D, making possible the evaluation of myocardial function in any region of the ventricle rather than at artificial boundary areas in the projection image. 4D LV models are reconstructed from a biplanar image sequence. The centerline and radial method, originally developed for analysis in 2D, are extended to 3D for assessment of cardiac motion based on our 4D ventricular model. Color-encoded ventricle models and 2D maps of heart wall dynamics are developed for visualization. Results obtained by using the methods presented herein are in correspondence with clinical findings