Cardiac arrhythmias after subarachnoid hemorrhage: risk factors and impact on outcome.
OBJECTIVE
Serious cardiac arrhythmias have been described in approximately 5% of patients after subarachnoid hemorrhage (SAH). The aim of this study was to identify the frequency, risk factors and clinical impact of cardiac arrhythmia after SAH.


METHODS
We prospectively studied 580 spontaneous SAH patients and identified risk factors and complications associated with the development of clinically significant arrhythmia. Multiple logistic regression analysis was used to calculate adjusted odds ratios for the effect of arrhythmia on hospital complications and 3-month outcome, as measured by the modified Rankin Scale, after controlling for age, neurological grade, APACHE-2 physiologic subscore, brain herniation and aneurysm size.


RESULTS
Arrhythmia occurred in 4.3% (n = 25) of patients. Atrial fibrillation and flutter were the most common arrhythmias, occurring in 76% (n = 19) of these patients. Admission predictors of cardiac arrhythmia included older age, history of arrhythmia and abnormal admission electrocardiogram (all p < 0.05). After adjusting for length of stay, hospital complications associated with arrhythmia included myocardial ischemia, hyperglycemia, and herniation (all p < 0.05). Arrhythmia was associated with an excess ICU stay of 5 days (p = 0.002). After adjusting for other predictors of outcome, arrhythmia was associated with an increased risk of death (adjusted OR 8.0, 95% confidence interval 1.9-34.0, p = 0.005), and death or severe disability (adjusted OR 6.9, 95% confidence interval 1.5-32.0, p = 0.014).


CONCLUSIONS
Clinically important arrhythmias, most often atrial fibrillation or flutter, occurred in 4% of SAH patients. Arrhythmias are associated with an increased risk of cardiovascular comorbidity, prolonged hospital stay and poor outcome or death after SAH, after adjusting for other predictors of poor outcome.
Neurological Intensive Care Unit, Department of Neurosurgery, Mount Sinai School of Medicine, New York, NY 10029, USA. Jennifer.Frontera@mountsinai.org
Jennifer A
JA
Frontera
Augusto
A
Parra
Daichi
D
Shimbo
Andres
A
Fernandez
J Michael
JM
Schmidt
Patricia
P
Peter
Jan
J
Claassen
Katja E
KE
Wartenberg
Fred
F
Rincon
Neeraj
N
Badjatia
Andrew
A
Naidech
E Sander
ES
Connolly
Stephan A
SA
Mayer
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000401:mortality; D001281:Atrial Fibrillation / Q000209:etiology; D001282:Atrial Flutter / Q000209:etiology; D004562:Electrocardiography; D004677:Encephalocele / Q000150:complications; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000150:complications; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications; D016017:Odds Ratio; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000401:mortality