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)