Depressed sympathovagal balance predicts mortality in patients with subarachnoid hemorrhage - 05/06/12
Abstract |
Objectives |
The objective of this study is to investigate the role of sympathovagal balance in predicting inhospital mortality by assessing power spectral analysis of heart rate variability (HRV) among patients with nontraumatic subarachnoid hemorrhage (SAH) in an emergency department (ED).
Methods |
A cohort of 132 adult patients with spontaneous SAH in an ED was prospectively enrolled. A continuous 10-minute electrocardiography for off-line power spectral analysis of the HRV was recorded. Using the inhospital mortality, the patients were classified into 2 groups: nonsurvivors (n = 38) and survivors (n = 94). The HRV measures were compared between these 2 groups of patients.
Results |
Having compared the various measurements, the very low–frequency component, low-frequency component, normalized low-frequency component (LF%), and low-/high-frequency component ratio (LF/HF) were significantly lower, whereas the normalized high-frequency component was significantly higher among the nonsurvivors than among the survivors. A multiple logistic regression model identified LF/HF (odds ratio, 2.16; 95% confidence interval [CI], 1.18-3.97; P = .013) and LF% (odds ratio, 0.78; 95% CI, 0.69-0.88; P < .001) as independent variables that were able to predict inhospital mortality for patients with SAH in an ED. The receiver operating characteristic area for LF/HF in predicting inhospital mortality was 0.957 (95% CI, 0.914-1.000; P < .001), and the best cutoff points was 0.8 (sensitivity, 92.1%; specificity, 90.4%).
Conclusions |
Power spectral analysis of the HRV is able to predict inhospital mortality for patients after SAH in an ED. A tilt in the sympathovagal balance toward depressed sympathovagal balance, as indicated by HRV analysis, might contribute to the poor outcome among these patients.
Le texte complet de cet article est disponible en PDF.Plan
☆ | Competing interests: None of the authors have any conflicts to disclose. |
☆☆ | Authors' contributions: The study was designed by T.F.C. and W.L.C. Acquisition of the data was performed by C.H.H., J.H.C., and W.L.C. Analysis and interpretation of data were done by T.F.C. and W.L.C. The statistical analysis was done by J.H.C. and W.L.C. The manuscript was drafted by T.F.C. Critical revision of the manuscript for important intellectual content was done by W.L.C. Final approval of the manuscript was done by T.F.C., C.H.H., J.H.C., and W.L.C. |
Vol 30 - N° 5
P. 651-656 - juin 2012 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
L’accès au texte intégral de cet article nécessite un abonnement.
Déjà abonné à cette revue ?