Gert Jan Mauritz1, J. Tim Marcus1, Nico Westerhof1, Pieter E. Postmus1, Anton Vonk Noordegraaf1
In PAH a prolonged time interval between pulmonary valve closure and tricuspid valve opening is observed. This period is assumed to measure a prolonged right ventricular (RV) relaxation, and to reflect diastolic dysfunction. In this study it was shown that this period is the consequence of a prolonged contraction of the RV free wall which continues after pulmonary valve closure causing a post-systolic contraction. In contrast the RV isovolumic relaxation period is not increased. Therefore, in clinical practice the isovolumic period between pulmonary valve closure and tricuspid valve opening is not a real measure of diastolic dysfunction in PAH patients.