A NOVEL EXERCISE TEST DEMONSTRATES REDUCED STROKE VOLUME AUGMENTATION BUT NO EVIDENCE OF PULMONARY HYPERTENSION IN PATIENTS WITH ADVANCED CYSTIC FIBROSIS - McKee, AJ; Davies, JC; Bilton, D; Taylor, A; Gatzoulis, M; Aurora, P; Muthurangu, V; Balfour-Lynn, IM (PEDIATRIC PULMONOLOGY, 2011)