Abstract 20867: Role of Pulmonary Function in Adults with Congenital Heart Disease with Reduced Exercise Tolerance
Introduction: It is recognized that Adults with congenital heart disease (ACHD) have reduced exercise tolerance. However, the contribution of subnormal pulmonary function (PFT) on exercise tolerance in adults with moderate and complex congenital heart disease is not well known. This study looks at the role of pulmonary function abnormalities in this patient population with reduced exercise tolerance assessed using cardiopulmonary exercise testing (CPET).
Methods: Over a period of 3 years, 126 ACHD patients (69 males, age 28±1, BSA 1.8±0.2, BMI 23.7±0.35) with moderate/complex heart disease based on the Bethesda classification underwent CPET; Lung function was measured by standard spirometry before CPET, which was performed according to a standardized ramped exercise algorithm on a bicycle ergometer. Parameters were recorded at rest, at anaerobic threshold and at maximum exercise. These included; work-load, watts; minute ventilation, VE, L/min; peak oxygen uptake, VO2max, ml/kg/min; carbon dioxide elimination, VCO2, ml/min; and VE/VCO2 ratio. Data were compared to predicted values (age, sex and BSA matched). Data were analyzed by Wilcoxon matched-pairs signed rank test.
Results: FVC and FEV1 were significantly reduced compared to predicted values. The FEV1/FVC ratio was 84.0 ± 0.2 %. CPET parameters Workload, VE, VO2 and VCO2 were significantly lower than predicted except VE/VCO2, which was increased (Table 1).
Conclusions: These data show that ACHD patients with moderate to complex disease in addition to reduction in exercise tolerance also have significant impairment in PFT. PFT show a restrictive pattern, possibly related to prior cardiac surgery and abnormalities in pulmonary perfusion. Thus restrictive lung function appears to be a contributing factor to diminished exercise tolerance in these patients.
- © 2010 by American Heart Association, Inc.