Optimal short-term outcomes in balloon pulmonary angioplasty: the minimum frequency of three sessions annually

Background: Balloon pulmonary angioplasty (BPA) is typically performed in a sequential manner. Objectives: This study aimed to determine the lowest frequency of BPA for patients who could not reach treatment goals in a short period. Design: Retrospective cohort. Methods: We retrospectively enrolled 186 BPA-treated patients diagnosed with chronic thromboembolic pulmonary hypertension. According to the accumulative number of performed BPA sessions or treated pulmonary vessels or the ratio of the number of treated pulmonary vessels/the number of baseline lesions (T/P) prior to the initial occurrence of clinical outcome or censored date, we divided patients into different groups. The principal outcome was clinical worsening. Results: After stratifying patients by the number of performed BPA sessions, most baseline parameters were comparable among groups. During follow-up, 31 (16.7%) of 186 patients experienced clinical worsening. The 6-month cumulative clinical worsening-free survival rates of ⩾2 performed sessions group were significantly higher than that of 1 performed session group. The 12-month cumulative rates of clinical worsening-free survival exhibited a declining pattern in the subsequent sequence: ⩾3, 2, and 1 performed BPA sessions, and this trend persisted when follow-up time exceeded 12 months. The 6-, 12-, and 24-month cumulative clinical worsening-free survival rates were comparable between patients with 3 and ⩾4 performed BPA sessions. Similar results were also observed when stratifying patients by the accumulative number of treated pulmonary vessels (⩽8, 9–16, ⩾17) and T/P (⩽0.789, 0.790–1.263, ⩾1.264). Conclusion: To achieve optimal short-term outcomes, patients might need to undergo ⩾2 BPA sessions or have ⩾9 pulmonary vessels treated or have T/P ⩾0.790 within 6 months, and undergo ⩾3 BPA sessions or have ⩾17 pulmonary vessels treated or have T/P ⩾1.264 within 12 months.