Perindopril improves six minute walking distance in older patients with left ventricular systolic dysfunction: a randomised double blind placebo controlled trial. - Hutcheon SD; Gillespie ND; Crombie IK; Struthers AD; McMurdo MET; Hutcheon, S D; Gillespie, N D; Crombie, I K; Struthers, A D; McMurdo, M E T (Heart, 2002)