Exercise Testing in Adults after Repair of Aortic Coarctation Evaluation of Cardiopulmonary Exercise Capacity and B-Type Natriuretic Protein Levels

The aim of the study was to investigate, in adult patients after successful repair of aortic coarctation, potential relationships between B-type natriuretic peptide levels and exercise capacity and the following factors: arterial hypertension, residual stenosis of the ascending aorta, and age at the time of surgery. The study group comprised 74 patients (45 men) aged 19 to 61 years (mean, 31.2 ± 9.8 yr), who had undergone surgery at the age of 0.5 to 34 years (mean, 10.4 ± 6.8 yr). The surgery was performed between 5 and 34 years earlier (mean, 21.4 ± 6.2 yr). A subgroup with residual aortic stenosis (significant when ≥25 mmHg) comprised 32 patients; a subgroup without residual stenosis comprised 42 patients. Patients were also divided into subgroups without arterial hypertension (n=32), with exercise-induced arterial hypertension (n=10), and with persistent arterial hypertension (n=32). All patients were in New York Heart Association functional class I. The control group comprised 30 healthy subjects (18 men) aged 26 to 46 years (mean, 32.2 ± 6.6 yr). After testing exercise capacity in accordance with a modified Bruce protocol, we concluded that the exercise capacity of adults is reduced after surgical repair of aortic coarctation. This reduction is more pronounced in patients who have arterial hypertension, but it is unaffected by residual stenosis of the descending aorta. Serum B-natriuretic peptide concentrations, as determined by immunoradiometric assay, are significantly elevated, which may result from pressure overload of the left ventricle or from residual myocardial lesions due to coarctation repair at an older age.