CT-Based Lung Size Matching in Delayed Chest Closure for Systemic Sclerosis Lung Transplantation

Delayed chest closure (DCC) during lung transplantation (LTx) is a controversial surgical approach that lacks research in systemic sclerosis (SSc) patients. We investigated outcomes, clinical risk factors, and CT-based lung size-matching parameters associated with DCC in SSc recipients.

This retrospective study included 92 SSc recipients (age 51 years ± 10, 56/92 (61.0%) females) who underwent bilateral LTx between 2007 and 2020. Of the recipients, 34.8% (32/92) underwent DCC. Recipient lung and chest cavity volumes were automatically computed from CT imaging using deep learning algorithms. Survival between groups was compared using Kaplan-Meier analysis. Multivariate logistic regression was used to identify risk factors and predict DCC occurrence using preoperative variables.

Recipients who underwent DCC had longer total vent duration (p = 0.001), more use of postoperative mechanical support (p = 0.001), longer ICU length of stay (p = 0.008), and lower incidence of pneumonia post-operation (p = 0.031). No significant difference in survival was observed between DCC and PCC recipients at 30 days (p = 0.713), 90 days (p = 0.267), 1 year (p = 0.941), and 5 years (p = 0.651). Clinical risk factors for DCC included BMI > 30 kg/m² (p = 0.009), tracheostomy (p = 0.002), atrial fibrillation (p = 0.012), decreased preoperative FEV1/FVC (p = 0.013), and previous chest operation (p = 0.020). Two CT-based measurements of lung matching were significantly associated with DCC occurrence (p = 0.021 and 0.050). The regression model achieved a mean AUC of 0.82 (0.70, 0.94) in retrospectively predicting DCC occurrence.

SSc recipients undergoing DCC have similar survival rates but experience more complications than PCC recipients. Clinical risk factors and CT-based size matching can be leveraged to predict DCC pre-transplant.