Isometric Exercise Increases the Diameter of the Ascending Aorta in Youth with Bicuspid Aortic Valves.

Abstract

Central arterial pressure rises to much higher levels during heavy isometric exercise compared to other forms of exercise. For this reason, patients with bicuspid aortic valves (BAV) are often restricted from heavy isometric exercise. Although this approach may be theoretically appealing, no data exist regarding the efficacy of this activity restriction.Patients between 12 and 21years old with isolated BAV were enrolled if they had a previous echocardiogram at least 2years prior to the current clinic visit. Patients were excluded if they had additional congenital heart disease, a diagnosed syndrome, or had undergone a procedure involving the aortic valve or ascending aorta. Patients completed a questionnaire regarding frequency and intensity of isometric exercise during the 3-month period prior to the visit. We compared aortic dimensions (Z-score), aortic stenosis, and aortic insufficiency between an echocardiogram performed as part of the current visit and one obtained 2-5years previously using paired t tests and multivariable regression controlling for age, gender, degree of aortic stenosis, and the presence of isometric exercise. In this sample of 50 adolescents with isolated bicuspid aortic valve, 30 (60%) subjects did not participate in any isometric exercise. Over an average of 2.9years (SD 0.9years), we did not find a significant difference between changes in the Z-score diameters of the aortic root (0.9 vs 0.9, p = 0.913) and ascending aorta Z-score (2.9 vs 2.9, p = 0.757), between subjects engaging and not engaging in isometric exercise. Further, we did not find that changes in valve function (i.e., aortic stenosis and aortic insufficiency) differed between the two groups.In this sample of adolescents with isolated bicuspid aortic valve, there was no medium-term increase in aortic dilation or worsening valve function in those who engaged in isometric exercise versus those who refrained from isometric exercise.