Geert Kleinnibbelink

Cardiac Rehabilitation in Pulmonary Hypertension 9 187 INTRODUCTION Despite introduction of pharmacological therapies to improve outcomes of pulmonary hypertension (PH), poor long-term survival remains present. 1 This highlights the need for alternative strategies to improve survival and lower morbidity, and to subsequently improve quality of life and lower socioeconomic costs. One such strategy relates to regular exercise training or prescription of cardiac rehabilitation (CR). A recent European Respiratory Society (ERS) statement in this journal highlighted the potential of CR for PH patients. 2 Specifically, CR improves exercise capacity, quality of life and improves symptoms (NYHA classification) and currently holds a class IIa recommendation. 2, 3 However, improvement of these outcomes have been observed only after relatively short time periods (3-4 months) and, more importantly, no study has examined the association between CR and mortality in PH patients. This latter aspect was identified as a key future challenge in the ERS-statement. 2 Although prospectively designed randomized clinical trials (RCTs) are preferred in this context, practical difficulties related to sample size, recruitment, and prolonged follow-up are important challenges. Therefore, adopting a retrospective observational study using a large electronic medical record (EMR) database, the objective of this study was to compare mortality between patients with primary PH with CR or exercise programme versus a propensity-matched control group of PH without CR or exercise programmes. We hypothesized that primary PH patients undergoing CR or exercise programmes are associated with lower mortality rates compared to primary PH patients without CR or exercise programmes. METHODS The retrospective analysis was conducted on December 14, 2020 using anonymized data within TriNetX, a global federated health research network with access to EMRs from participating academic medical centres, specialty physician practices, and community hospitals, predominantly in the United States. Patients with PH were identified via Centers for Disease Control and Prevention (CDC) coding using ICD-10-CM code I27.0 primary pulmonary hypertension. All patients were aged ≥ 18 years with primary PH recorded in EMRs at least 18-months before the search date to allow for 1-year follow-up from CR. CR was identified from ICD-10-CM code Z71.82 (Exercise counselling), HCPCS code S9472