Development and Validation of a Nomogram for Balloon Pulmonary Angioplasty-Related Complications in Patients with Chronic Thromboembolic Pulmonary Hypertension

Abstract

Background: Balloon pulmonary angioplasty (BPA)-related complications are not uncommon and could contribute to perioperative mortality. However, there is a lack of a prediction model for BPA-related complications. Methods: Data from consecutive patients diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) who underwent BPA were retrospectively analyzed. The primary outcome was BPA-related complications. The secondary outcomes were mortality and hemodynamics after BPA. Results: A total of 207 patients with 614 BPA sessions were included. Complications occurred during 63 sessions (10.26%) in 49 patients. Hemoptysis or hemosputum (6.51%) was the most common complication, whereas pulmonary reperfusion edema was rare (0.49%). Multivariable logistic regression identified that disease duration, mean pulmonary arterial pressure (mPAP) and the proportion of occlusion lesions were correlated with BPA complications. A nomogram was constructed accordingly, which had the highest area under curve (0.703) and was superior to previously reported predictors [nomogram vs. mPAP, net reclassification index (95% confidence interval (CI)), 0.215 (0.002, 0.427), p = 0.047; integrated discrimination index (95% CI), 0.059 (0.010, 0.109), p = 0.018]. The nomogram was found to be accurate based on validation and calibration (slope 0.978, Bier score 0.163). After adjusting for the number of BPA sessions in multivariable linear regression, the occurrence of complications was not associated with hemodynamic improvement after BPA. The 3-year survival was also comparable between patients with and without complications (98.0% vs. 94.8%, log-rank p = 0.503). Conclusions: The nomogram, comprising mPAP, the proportion of occlusion lesions and disease duration, could better predict BPA-related complications than previously reported single parameters. Distinctively, the occurrence of complications did not impair the beneficial impact of BPA on hemodynamics and survival. The occurrence of complications should not discourage patients from continuing BPA sessions.