OBJECTIVES: This study sought to compare, in post- @entity583 @entity1 , baroreflex sensitivity ( @entity4375 ) measured by the @entity2647 method ( @entity815 - @entity4375 ) with that estimated by the Robbe (Robbe- @entity4375 ) and Pagani (alpha-low frequency [LF] and alpha-high frequency [HF]) spectral techniques. BACKGROUND: @entity4375 assessed by @entity815 - @entity4375 has been shown to be of prognostic value in @entity1 with a previous @entity583 , but the need for drug injection limits the use of this technique. Several noninvasive methods based on spectral analysis of systolic arterial pressure and heart period have been proposed, but their agreement with @entity815 - @entity4375 has never been investigated in post- @entity583 @entity1 . METHODS: The linear association and the agreement between each spectral measurement and @entity815 - @entity4375 were assessed by correlation analysis and by computing the relative bias and the limits of agreement in 51 post- @entity583 @entity1 . RESULTS: The correlation with @entity815 - @entity4375 was r = 0.63 for Robbe- @entity4375 , r = 0.62 for alpha-LF and r = 0.59 for alpha-HF. The relative bias was significant for alpha-LF (2.6 ms/mm Hg, p < 0.001) and alpha-HF (2.5 ms/mm Hg, p = 0.01) and not significant (-0.6 ms/mm Hg, p = 0.3) for Robbe- @entity4375 . The normalized limits of agreement ranged from -98% to 95% for Robbe- @entity4375 , from -67% to 126% for alpha-LF and from -108% to 143% for alpha-HF. When @entity1 were classified according to left ventricular ejection fraction (LVEF, cutoff value 40%), the relative bias was higher in @entity1 with a depressed LVEF, although statistical significance was high only for Robbe- @entity4375 and was borderline for alpha-LF. The limits of agreement were similar in both groups of @entity1 (p > 0.3). CONCLUSIONS: Despite a substantial linear association, the agreement between spectral measurements and @entity815 - @entity4375 in post- @entity583 @entity1 is weak because the difference can be as large as the @entity4375 value being estimated. @entity815 - @entity4375 is the measurement most associated with @entity73 . Because several factors within each method contribute to the overall difference, neither method can be defined as being better than the other in estimating @entity1017 , nor can one be used as an alternative to the other. Ad hoc studies are needed to assess which method provides the most useful physiologic or pathophysiologic information or the most accurate prediction of prognosis.

Assessing baroreflex sensitivity in post- @entity583 XXXX : comparison of spectral and @entity2647 techniques.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity73 :: ('MESH:D003072', 'Disease') :: ['hemodynamic impairment'] @entity4375 :: ('11246', 'Species') :: ['BRS'] @entity2647 :: ('MESH:D010656', 'Chemical') :: ['phenylephrine'] @entity1017 :: ('MESH:D015430', 'Disease') :: ['baroreflex gain'] @entity583 :: ('MESH:D009203', 'Disease') :: ['myocardial infarction'] @entity815 :: ('CHEBI:28044', 'Chemical') :: ['Phe']
@entity1 :: (9606,Species) :: ['patients']
