BACKGROUND: Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis. METHODS AND RESULTS: The alpha-index was measured by means of the spectral analysis of RR and systolic blood pressure variabilities in both the high- and low-frequency bands; sequences were identified from simultaneously recorded time series in which the RR and systolic blood pressure concurrently increased or decreased. Noninvasive baroreflex sensitivity tests were performed during both spontaneous and controlled respiration. Fifty-two consecutive patients with recent myocardial infarction underwent the analyses. Although the correlations between phenylephrine and either of the noninvasive methods were always significant, those found during controlled respiration had the highest r values (r=.70). However, the limits of agreement calculated by means of the Bland and Altman method were wide for both noninvasive methods. CONCLUSIONS: The results obtained by means of noninvasive baroreflex sensitivity assessments should not be used in clinical practice as an alternative to those obtained by the phenylephrine method.
BACKGROUND: Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis. METHODS AND RESULTS: The alpha-index was measured by means of the spectral analysis of RR and systolic blood pressure variabilities in both the high- and low-frequency bands; sequences were identified from simultaneously recorded time series in which the RR and systolic blood pressure concurrently increased or decreased. Noninvasive baroreflex sensitivity tests were performed during both spontaneous and controlled respiration. Fifty-two consecutive patients with recent myocardial infarction underwent the analyses. Although the correlations between phenylephrine and either of the noninvasive methods were always significant, those found during controlled respiration had the highest r values (r=.70). However, the limits of agreement calculated by means of the Bland and Altman method were wide for both noninvasive methods. CONCLUSIONS: The results obtained by means of noninvasive baroreflex sensitivity assessments should not be used in clinical practice as an alternative to those obtained by the phenylephrine method.
Authors: Qi Fu; Robin P Shook; Kazunobu Okazaki; Jeffrey L Hastings; Shigeki Shibata; Colin L Conner; M Dean Palmer; Benjamin D Levine Journal: J Physiol Date: 2006-09-28 Impact factor: 5.182
Authors: Christopher E Schwartz; Marvin S Medow; Zachary Messer; Julian M Stewart Journal: Am J Physiol Regul Integr Comp Physiol Date: 2013-04-10 Impact factor: 3.619
Authors: Viktor Švigelj; Matjaž Šinkovec; Viktor Avbelj; Roman Trobec; Ludovit Gaspar; Daniel Petrovič; Peter Kruzliak Journal: Wien Klin Wochenschr Date: 2016-03-15 Impact factor: 1.704