Proposition of quantitative parameters for pre- and early post-operative assessment in pulmonary thromboendarterectomy – An Indian prospective study

Introduction Chronic thromboembolic pulmonary hypertension results from the incomplete resolution of the vascular obstruction associated with pulmonary embolism. Symptoms are exertional dyspnoea and fatigue, and over a period of time, right ventricular dysfunction sets in. Pulmonary thromboendarterectomy is an effective surgical remedy for this condition. Our study is an initial post-operative experience of pulmonary thromboendarterectomy and we have also tried to formulate quantitative parameters for the prediction of the post-operative course in patients who are undergoing surgery. Methods Twenty patients with chronic thromboembolic pulmonary hypertension underwent pulmonary thromboendarterectomy between July 2017 and January 2020. Pre-operatively, each patient was subjected to the (i) 6-min walk test, (ii) pre-operative brain natriuretic peptide values and (iii) pulmonary artery systolic pressure. Following the surgery and subsequent discharge, the patients were followed up at intervals of 15 days, 1, 3, 6, 9 months and at 1 year. At one year post-operatively, the same three quantitative tests were performed on each subject. Results Post-operatively, the mean 6-min walk distance was 499.75 m as against 341.35 m pre-operatively ( p < 0.0001). Mean brain natriuretic peptide was 8.69 pm/l as against 47.58 pm/l pre-operatively ( p < 0.0001). Mean pulmonary artery systolic pressure was 22.25 as against 67.1 pre-operatively ( p < 0.0001). Conclusion 6-Min walk test, brain natriuretic peptide and pulmonary artery systolic pressure could be considered as useful predictors of the haemodynamic severity of disease and predict the post-operative outcome.