b-Blockers and XXXX differentially affect cardiopulmonary function and left ventricular filling index.

@entity1 @entity64 @entity26 @entity453 @entity67 @entity15726
OBJECTIVE: @entity1 with left ventricular (LV) @entity67 are characterized by exertional dyspnoea. Heart rate (HR) reduction by b-blockers can improve exercise tolerance by prolonging LV filling, but their negative inotropic and lusitropic properties can be detrimental in this disease. We tested the effects of administering @entity15726 , a HR-lowering drug without impact on cardiac kinetics that may favorably affect diastolic function. METHODS: Twenty-four @entity1 with @entity453 ( @entity453 ) and normal LV ejection fraction on chronic b-blocker therapy were included. NT-proBNP serum levels were determined prior to and after cardiopulmonary exercise. b-Blockers were then replaced by @entity15726 and @entity1 were re-tested after 6 weeks. @entity1 were initially classified as having a low (E/e'   <=  8; n  =  11) or high (E/e'  >  8; n  =  13) LV filling index. RESULTS: E/e' significantly decreased during @entity15726 therapy in @entity1 with high E/e' (10.7      2.9 vs. 8.9      1.7; p  <  0.01), whereas no difference occurred in @entity1 with low E/e' (6.4      0.7 vs. 6.5      1.1; p  =  ns). With @entity15726 , @entity1 with high E/e' had an increased @entity26 uptake at the anaerobic threshold (from 10.8      1.4 to 11.8      1.9  ml/min/kg; p  <  0.05) and a steeper slope of the initial @entity26 pulse curve (from 293      109 to 359      117    l/beat/kg/W; p  <  0.05). Moreover, @entity1 with high E/e' had lower NT-proBNP serum levels at rest (169      207 vs. 126      146  pg/ml; p  <  0.05) and after exercise (190      256 vs. 136      162  pg/ml; p  <  0.05) during @entity15726 therapy. CONCLUSIONS: In @entity1 with @entity453 and elevated E/e', switching therapy from b-blockers to @entity15726 may cause a reduction in LV filling pressures and an improved @entity64 volume response to exercise.
