Cardiopulmonary Exercise Testing Following Open Repair for a Proximal Thoracic Aortic Aneurysm or Dissection

Purpose: There are limited data on cardiopulmonary exercise testing (CPX) and cardiorespiratory fitness (CRF), following open repair for a proximal thoracic aortic aneurysm or dissection. The aim was to evaluate serious adverse events, abnormal CPX event rate, CRF (peak oxygen uptake, o(2peak)), and blood pressure. Methods: Patients were retrospectively identified from cardiac rehabilitation participation or prospectively enrolled in a research study and grouped by phenotype: (1) bicuspid aortic valve/thoracic aortic aneurysm, (2) tricuspid aortic valve/thoracic aortic aneurysm, and (3) acute type A aortic dissection. Results: Patients (n = 128) completed a CPX a median of 2.9 mo (interquartile range: 1.8, 3.5) following repair. No serious adverse events were reported, although 3 abnormal exercise tests (2% event rate) were observed. Eighty-one percent of CPX studies were considered peak effort (defined as respiratory exchange ratio of >= 1.05). Median measured o(2peak) was <36% predicted normative values (19.2 mL center dot kg(-1.)min(-1) vs 29.3 mL(.)kg(-1.)min(-1), P < .0001); the most marked impairment in o(2peak) was observed in the acute type A aortic dissection group (<40% normative values), which was significantly different from other groups (P < .05). Peak exercise systolic and diastolic blood pressures were 160 mm Hg (144, 172) and 70 mm Hg (62, 80), with no differences noted between groups. Conclusions: We observed no serious adverse events with an abnormal CPX event rate of only 2% 3 mo following repair for a proximal thoracic aortic aneurysm or dissection. o(2peak) was reduced among all patient groups, especially the acute type A aortic dissection group, which may be clinically significant, given the well-established prognostic importance of reduced cardiorespiratory fitness.