Determinants of Exercise Capacity After Arterial Switch Operation for Transposition of the Great Arteries

Monitoring the Patient with Transposition of the Great Arteries: Arterial Switch Versus Atrial Switch

“…Studies report peak volume of oxygen consumption (VO 2 ) measurements of ABP patients of around 70% to 75% predicted [14,15]. During childhood, exercise performance after ASO seems better, with peak VO 2 levels averaging 80% to 85% predicted [14,17,18]. However, in our experience, adult ASO patients exhibit peak VO 2 levels similar to those seen after ABPs [19••].…”

“…Although peak exercise heart rates are reduced after ASO [17], the reduction is sufficient to be classed as abnormal in only 5% of cases and is unrelated to peak exercise capacity [18]. It seems that issues related to pulmonary blood flow may be more important in this group of patients [18,24].…”

Exercise Testing and Training in Children With Congenital Heart Disease

“…28,37,[65][66][67][68][69][70] Residual hemodynamic lesions certainly account for some of this phenomenon. However, it has been observed that children with CHD often lead relatively sedentary lifestyles, perhaps on account of restrictions imposed on them by physicians, parents, teachers, coaches, or the children themselves.…”

Arterial switch operation for transposition of great arteries: late results in adult patients

“…It has been hypothesized that after AsO, a residual sympathetic denervation might contribute to a blunted exercise performance either through a chronotropic incompetence, which has been found in more than one third of patients, that caused an inappropriate contractile response to exercise, in a similar way to that observed after cardiac transplantation. An abnormal heart rate response to exercise has prognostic implications, as it is known to be associated with increased mortality in adults with congenital heart disease 64,65 . A residual RVOt obstruction has also been related to a reduced peak VO2, likely because this causes the RV to cope with excessive pressure load, which, in turn, hampers the physiologic increase in cardiac output during exercise 64 .…”

“…An abnormal heart rate response to exercise has prognostic implications, as it is known to be associated with increased mortality in adults with congenital heart disease 64,65 . A residual RVOt obstruction has also been related to a reduced peak VO2, likely because this causes the RV to cope with excessive pressure load, which, in turn, hampers the physiologic increase in cardiac output during exercise 64 . Furthermore, in patients with more peripheral obstruction of the pulmonary branches, in addition to a reduced peak VO2, an increased ventilatory response has been reported.…”