Abnormal lung function in adults with congenital heart disease: prevalence, relation to cardiac anatomy, and association with survival.

BACKGROUND: Restrictive lung defects are associated with higher mortality in patients with acquired chronic heart failure. We investigated the prevalence of abnormal lung function, its relation to severity of underlying cardiac defect, its surgical history, and its impact on outcome across the spectrum of adult congenital heart disease. METHODS AND RESULTS: A total of 1188 patients with adult congenital heart disease (age, 33.1±13.1 years) undergoing lung function testing between 2000 and 2009 were included. Patients were classified according to the severity of lung dysfunction based on predicted values of forced vital capacity. Lung function was normal in 53% of patients with adult congenital heart disease, mildly impaired in 17%, and moderately to severely impaired in the remainder (30%). Moderate to severe impairment of lung function related to complexity of underlying cardiac defect, enlarged cardiothoracic ratio, previous thoracotomy/ies, body mass index, scoliosis, and diaphragm palsy. Over a median follow-up period of 6.7 years, 106 patients died. Moderate to severe impairment of lung function was an independent predictor of survival in this cohort. Patients with reduced force vital capacity of at least moderate severity had a 1.6-fold increased risk of death compared with patients with normal lung function (P=0.04). CONCLUSIONS: A reduced forced vital capacity is prevalent in patients with adult congenital heart disease; its severity relates to the complexity of the underlying heart defect, surgical history, and scoliosis. Moderate to severe impairment of lung function is an independent predictor of mortality in contemporary patients with adult congenital heart disease.

Comprehensive use of cardiopulmonary exercise testing identifies adults with congenital heart disease at increased mortality risk in the medium term.

BACKGROUND: Parameters of cardiopulmonary exercise testing were recently identified as strong predictors of mortality in adults with congenital heart disease. We hypothesized that combinations of cardiopulmonary exercise testing parameters may provide optimal prognostic information on midterm survival in this population. METHODS AND RESULTS: A total of 1375 consecutive adult patients with congenital heart disease (age, 33±13 years) underwent cardiopulmonary exercise testing at a single center over a period of 10 years. Peak oxygen consumption (peak V(O(2))), ventilation per unit of carbon dioxide production (V(E)/V(O(2)) slope), and heart rate reserve were measured. During a median follow-up of 5.8 years, 117 patients died. Peak V(O(2)), heart rate reserve, and V(E)/V(O(2)) slope were related to midterm survival in adult patients with congenital heart disease. Risk of death increased with lower peak V(O(2)) and heart rate reserve. A higher V(E)/V(O(2)) slope was also related to increased risk of death in noncyanotic patients, whereas the V(E)/V(O(2)) slope was not predictive of mortality in cyanotic patients. The combination of peak V(O(2)) and heart rate reserve provided the greatest predictive information after adjustment for clinical parameters such as negative chronotropic agents, age, and presence of cyanosis. However, the incremental value of these exercise parameters was reduced in patients with peak respiratory exchange ratio <1.0. CONCLUSIONS: Cardiopulmonary exercise testing provides strong prognostic information in adult patients with congenital heart disease. Prognostication should be approached differently, depending on the presence of cyanosis, use of rate-lowering medications, and achieved level of exercise. We provide 5-year survival prospects based on cardiopulmonary exercise testing parameters in this growing population.