Persistent exercise limitation after successful pulmonary endoarterectomy: frequency and determinants

BACKGROUND: After successful pulmonary endoarterectomy (PEA), patients may still suffer from exercise limitation, despite normal pulmonary vascular resistance. We sought to assess the proportion of these patients after the extension of PEA to frail patients, and the determinants of exercise limitation. METHODS: Out of 553 patients treated with PEA from 2008 to 2016 at our institution, a cohort of 261 patients was followed up at 12 months. They underwent clinical, haemodynamic, echocardiographic, respiratory function tests and treadmill exercise testing. A reduced exercise capacity was defined as Bruce test distance < 400 m. RESULTS: Eighty patients did not had exercise testing because of inability to walk on treadmill and/or ECG abnormalities Exercise limitation 12 months after PEA was present in 74/181 patients (41, 95%CI 34 to 48%). The presence of COPD was more than double in patients with exercise limitation than in the others. Patients with persistent exercise limitation had significantly higher mPAP, PVR, HR and significantly lower RVEF, PCa, CI, VC, TLC, FEV1, FEV1/VC, DLCO, HbSaO2 than patients without. The multivariable model shows that PCa at rest and TAPSE are important predictors of exercise capacity. Age, COPD, respiratory function parameters and unilateral surgery were also retained. CONCLUSIONS: After successful PEA, most of the patients recovered good exercise tolerance. However, about 40% continues to suffer from limitation to a moderate intensity exercise. Besides parameters of right ventricular function, useful information are provided by respiratory function parameters and COPD diagnosis. This could be useful to better address the appropriate therapeutic approach.