Serial cardiorespiratory exercise testing in patients with congenital heart disease

Abstract

Aerobic capacity of patients with different forms of congenital heart disease was serially evaluated in 79 patients and the evolution was correlated with the lesion and the level of daily activity. The patients were divided into six groups: patients with a small ventricular septal defect (VSD) with mini shunt (n = 14), mild pulmonary valve stenosis with gradient < 40 mm Hg (PS) (n = 12), mild to moderate aortic valve stenosis (gradient 36 +/- 17 mmHg) (AS) (n = 12), patients 4.7 +/- 2.1 years after repair of tetralogy of Fallot (PO-TF) (n = 16), patients 2.2 +/- 2.9 years after closure of a high flow/high gradient VSD (PO-VSD) (n = 13), and patients 2.6 +/- 1.7 years after Fontan repair (Fontan-PO) (n = 12). Aerobic capacity was assessed by determination of the ventilatory anaerobic threshold (VAT). VAT reflects the highest aerobic exercise level prior to a disproportionate increase of CO2 and ventilation relative to O2 uptake; it is independent of patient motivation. Data are expressed as percentage of normal O2 uptake at VAT, determined in 234 age/gender matched controls. The habitual level of physical activity was assessed by a standardised questionnaire. Aerobic capacity in all subgroups of patients, even with very mild defects, was at or below the lower limit of normal. Children left unrestricted from physical exercise (VSD, PS, PO-VSD) had no change over the study period. However, aerobic capacity of patients with medically imposed physical restrictions (AS) and significant residual haemodynamic lesions (PO-TF, Fontan) decreased with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary exercise testing in congenital heart disease: (contra)indications and interpretation

“…33 Reybrouck et al found that, irrespective of the type of heart defect, the VT was always below the normal value in children with CHD. 49 The lowest values were recorded in patients after the Fontan operation (62±10% of the normal value). 49 …”

“…49 The lowest values were recorded in patients after the Fontan operation (62±10% of the normal value). 49 …”

Exercise capacity and impact of exercise training in patients after a Fontan procedure: A review

“…Nevertheless, the long-term impact of this procedure on exercise tolerance is equivocal. Some may increase their exercise tolerance during the six years following surgery (16), while other may have a deterioration in their exercise tolerance (17). Deconditioning may contribute to this deterioration because aerobic exercise training has been shown to improve these patients' functional capacity (18)(19)(20)(21).…”

“…Deconditioning may contribute to this deterioration because aerobic exercise training has been shown to improve these patients' functional capacity (18)(19)(20)(21). Nevertheless, this long-term decline in exercise tolerance following the procedure may also be related to the disease progression (17) or to the reduced capacity to increase the cardiac output (Q) in response to exercise secondary to the Fontantype circulation, thus limiting the oxygen transport to the periphery (22,23). Slower oxygen uptake kinetics, ie, the precise integration of the cardiorespiratory system required to transport the oxygen from the atmosphere through active muscles to achieve oxidative phosphorylation (24), is well documented in patients with coronary artery disease, cyanotic congenital heart disease or heart failure (25)(26)(27)(28)(29)(30)(31).…”

“…This reduction may be the consequence of an intrapulmonary right-to-left shunt that may become more important over time following the procedure, coronary sinus blood return to the pulmonary venous atrium, an intracardiac rightto-left shunt, a significant physiological dead space and/or a ventilation/perfusion mismatch with an abnormal pulmonary blood flow distribution (10,14,17,37,47). The lower arterial blood saturation may also be the result of a flow increment in the lungs' superior lobes with increased pulmonary vascular resistance (47).…”