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Aims: Despite refinements in balloon pulmonary angioplasty (BPA), total occlusion remains a challenge in chronic thromboembolic pulmonary hypertension (CTEPH). Owing to their low success and high complication rates, most interventional cardiologists are reluctant to address total occlusion, and there is a paucity of literature on BPA performance in total occlusion. We aimed to classify total occlusion according to morphology and present an illustrative approach for devising a tailored treatment strategy for each distinct type of total occlusion. Methods and results: All patients diagnosed with CTEPH who underwent BPA between May 2018 and May 2022 at Fuwai Hospital in Beijing, China, were included retrospectively. A total of 204 patients with CTEPH who underwent BPA were included in this study. Among these, 38 occluded lesions were addressed in 33 patients. Based on the morphology, we categorized the lesions into three groups: pointed‐head, round‐head, and orifice occlusions. Pointed‐head occlusion could be successfully addressed using soft‐tip wire, round‐head occlusion warranted hard‐tip wire and stronger backup, and orifice occlusion warranted the strongest backup force. The success rates for each group were as follows: pointed‐head (95.45%), round‐head (46.15%), and orifice occlusion (33.33%), with orifice occlusion having the highest complication rate (50%). The classification of occlusion was associated with BPA success (round‐head occlusion vs. pointed‐head occlusion, OR 24.500, 95% CI 2.498–240.318, P = 0.006; orifice occlusion vs. pointed‐head occlusion, OR 42.000, 95% CI 3.034–581.434, P = 0.005). Conclusions: Occlusion morphology has a significant impact on BPA success and complication rates. A treatment strategy tailored to each specific occlusive lesion, as outlined in the present study, has the potential to serve as a valuable guide for clinical practitioners. [ABSTRACT FROM AUTHOR]

Modern transportation systems are moving towards shared mobility with diverse demands, and resource aggregation and coordination among different transport modes have become more and more significant. In this study, we investigate the integrated train capacity allocation and timetable coordination for multimodal railway networks to release the congestion of transfer hubs between metro and mainline rail networks. We consider that a part of vehicles can be dynamically allocated to some metro trains to increase their capacity to take more passengers at transfer hubs alighting from mainline rail trains. We formulate this problem into a mixed-integer linear programming (MILP) model, which simultaneously generates the coordinated timetables of both metro and mainline rail trains, as well as the train capacity allocation strategy in the network. The objectives are to minimize the passenger travel time, passenger transfer time at the hubs and the operational costs for rail managers. To tackle computational challenges in real-world instances, we develop an exact branch-and-cut solution algorithm to generate (near-)optimal solutions more efficiently. In our algorithm, we propose five sets of valid inequalities that are dynamically added to the model to strengthen the linear relaxation bounds at each node. We also design a customized branching strategy in the search tree by imposing branching on the key decision variables regarding the train sequences at transfer stations. Real-world case studies based on the operational data of a realistic multimodal railway network in Beijing are conducted to verify the effectiveness of our approach. The results demonstrate that our branch-and-cut-based approach outperforms commercial solvers regarding solution quality and computational efficiency. Compared to the current non-coordinated train timetable in practice, our approach by flexibly allocation train capacities can reduce the passenger transfer waiting time by over 40%. • We address the integrated train capacity allocation and timetable coordination for multimodal railway networks. • A mixed-integer linear programming model is proposed to optimize the schedules of railway and metro trains. • We develop an exact branch-and-cut algorithm to generate high quality solutions. • The effectiveness of the proposed approaches is verified by the numerical experiments. [ABSTRACT FROM AUTHOR]