Quantitative Assessment of Right Ventricular Volumes in Severe Chronic Thromboembolic Pulmonary Hypertension using Transthoracic Three-dimensional Echocardiography: Changes due to Pulmonary Thromboendarterectomy

AIMS: Evaluation of a three-dimensional reconstruction method to show the changes of right ventricular volume and systolic function when patients undergo pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension. METHODS AND RESULTS: In the examination of 11 patients (four female, seven male; age 56+/-10 years) before and after pulmonary thromboendarterectomy, end-diastolic and end-systolic right ventricular volumes were determined as a sum total of the calculated volumes of derived parallel slices of the right ventricle. Using a Tomtec workstation and a Vingmed CFM 800 echocardiography device, the acquired data were ECG-and respiration-triggered in the course of transthoracic examination, using step intervals of 5 degrees. The ventricular outline was traced manually on 5mm slices from longitudinal cut planes. For subsequent correction, their area measurements were displayed and the volume cross-checked against the volume from orthogonal cut planes. End-diastolic and end-systolic volumes could be quantified in 11/11 cases before surgery, but data could only be attained for 9/11 patients after surgery, because a limited apical window rendered the postoperative three-dimensional reconstruction impossible in two cases. Before surgery, right ventricular size was larger than normal and systolic function was clearly impaired in all of the patients (end-diastolic volume: 121+/-37 ml; end-systolic volume 91+/-30 ml; ejection fraction 25+/-8%). The decrease in mean pulmonary artery pressure after surgery was significant (47+/-8 vs 26+/-8 mmHg; P<0.05). End-diastolic and end-systolic right ventricular volumes had been reduced (80+/-33 ml and 54+/-31 ml respectively), and the ejection fraction had increased (36+/-9%). CONCLUSIONS: Successfully performed pulmonary thromboendarterectomy leads to a significant reduction of right ventricular chamber size and improvement of systolic function, which can be determined with great precision and quite easily, using transthoracic three-dimensional echocardiography. Published by Elsevier Science Ltd. All rights reserved.