British randomised controlled trial of AV and VV optimization ("BRAVO") study: rationale, design, and endpoints - Whinnett, ZI; Sohaib, SMA; Jones, S; Kyriacou, A; March, K; Coady, E; Mayet, J; Hughes, AD; Frenneaux, M; Francis, DP (BMC CARDIOVASCULAR DISORDERS, 2014)