Arcasoy, Selim M.

Background. The spirometric response to standard-of-care (SOC) immunosuppressive therapy for the management of bronchiolitis obliterans syndrome (BOS) has been sparsely reported in the literature. Data from a Medicare-approved Registry were analyzed to characterize the effectiveness/durability of a wide range of SOC interventions to manage the decline of lung function and to validate the study spirometric criteria for initiation of rescue therapy. Methods. Lung transplant recipients with refractory BOS at 21 US collaborating centers were enrolled in the Registry. Data included both nonspirometric (eg, demographic, Immunosuppressive Regimens for management of BOS) and spirometric parameters (ie, forced expiratory volume in 1 s [FEV 1 ] measurements and derived indices). The utility of study FEV 1 criteria for treatment (ie, statistically significant rate of FEV 1 decline >30 mL/mo) was evaluated by comparing the spirometric course between participants who met or did not meet this criterion. Results. Only 21% of participants treated with SOC therapy had >50% decrease (76 ± 25% decrease) in the rate of FEV 1 decline. Although 51% of participants had a partial response (rate of FEV 1 decline decreased on average 71%), 49% of participants had a substantial increase (mean increase 224%). The FEV 1 criterion for treatment was able to identify 19% of participants (48/258) who achieved durable stabilization (ie, nonsignificant rate of FEV 1 <30 mL/mo) with SOC therapy. Conclusions. Patients with BOS have a widely variable response to SOC therapy. Our findings support the use of FEV 1 rate of decline to assess response to SOC therapy and to ensure appropriate assignment of participants with refractory BOS to rescue therapy treatment cohorts.

BACKGROUND. We developed a prospective, multicenter “registry” to evaluate the effect of extracorporeal photopheresis for lung transplant recipients who develop chronic lung allograft dysfunction (CLAD) with the bronchiolitis obliterans syndrome (BOS) phenotype (CLAD/BOS) and who are refractory to conventional standard-of-care therapy. METHODS. Data from 258 lung transplant recipients enrolled in the Registry between April 2015 and April 2022 were included in this analysis. All recorded parameters (eg, demographics), including forced expiratory volume in 1 s (FEV1) measurements and indices (FEV1% baseline, FEV1 rate of decline) at several time periods, were included in multivariate linear/logistic and Kaplan-Meier analyses to evaluate potential associations with survival. RESULTS. Mortality at 6 and 12 mo after CLAD/BOS diagnosis was 5% and 14%, whereas mortality at 6 and 12 mo after enrollment was 15% and 26%, respectively. The primary cause of death in the cohort was respiratory failure or graft failure (74%). Rate of FEV1 decline (log) at enrollment was independently associated with survival (log days) from CLAD/BOS diagnosis and enrollment (r = 0.55 and r = 0.3, respectively). The rates of FEV1 decline among survivors were lower (–77 ± 89 mL/mo) compared with nonsurvivors (–148 ± 155 mL/mo) at 6 mo after enrollment (P = 0.0001). CONCLUSIONS. The rate of FEV1 decline quantified using at least 5 FEV1 measurements is a robust surrogate outcome. We plan to use these findings to revise our randomized controlled trial to facilitate risk adjustment using FEV1 rate of decline strata at enrollment and as a scientifically valid surrogate for outcome.

ABSTRACTLung transplantation is indicated for selected patients with advanced pulmonary arterial hypertension (PAH). We used a modified Delphi process to develop recommendations on care of patients with PAH undergoing lung transplantation. This Delphi panel was recruited from the Pulmonary Vascular Research Institute's Innovative Drug Discovery Initiative ‐ Lung Transplantation Workstream, consisting of clinical and research experts in PAH and lung transplantation. In this process, 29 panelists were given open‐ended questions, querying topics related to lung transplantation in PAH. A steering group converted the responses into discrete statements. Panelists then rated agreement using a Likert scale in two further survey rounds: −5 (strongly disagree) to 5 (strongly agree). Consensus was defined as mean ≥ 2.5 or ≤ −2.5, with a standard deviation not crossing zero. Consensus was reached on 141 of 223 statements. Notable areas of consensus were for early discussions about transplantation, and agreement with previously published referral and listing criteria. There was agreement that lung transplantation could be offered in sick candidates, including those with concurrent renal or hepatic insufficiency. Bilateral lung transplantation was considered the procedure of choice for most patients, with rare indications for heart‐lung transplantation. Consensus on bridging strategies included use of veno‐arterial extracorporeal membrane oxygenation and preemptive awake cannulation in those with severe right ventricular dysfunction. Consensus was also achieved on intraoperative use of invasive hemodynamic monitoring, and prolonged postoperative circulatory support guided by hemodynamic response and echocardiography. Patients with PAH undergoing transplantation require specialized management, which differs somewhat from other candidates.