Electrocardiographic Abnormalities Predict Adverse Clinical Outcomes in Patients with Subarachnoid Hemorrhage

Background: We conducted a retrospective cohort study of a large sample to assess whether electrocardiographic (ECG) abnormalities are independently associated with the occurrence of neurogenic pulmonary edema (NPE), delayed cerebral ischemia (DCI), and in-hospital death after nontraumatic subarachnoid hemorrhage (SAH). Methods: In this retrospective observational study, patients who were admitted within 72 hours of SAH symptom onset between 2013 and 2015 were enrolled. Twelve-lead ECG findings obtained within 72 hours after SAH and the presence of NPE, DCI, and in-hospital death were collected based on the results reported in the medical records. Results: We included 834 patients. NPE occurred in 192 patients (23%). The median delay from SAH onset to NPE was 3 days (interquartile range [IQR]: 5 days). DCI occurred in 223 patients (27%; median delay to DCI, 4 days; IQR: 5 days). In total, 141 patients (17%) died in the hospital (median time to death, 12 days; IQR: 18 days). The frequency of ECG abnormalities for all enrolled patients was 65%. Corrected QT prolongation had an adjusted risk ratio (RR) of 1.5 (1.1-2.2) for NPE and 1.8 (1.3-2.4) for DCI. ST depression had an adjusted RR of 3.0 (1.2-7.5) for in-hospital death. NSSTTCs (nonspecific ST-or T-wave changes) had an adjusted RR of 2.7 (1.8-4.2) for NPE, 2.8 (1.9-4.3) for DCI, and 2.2 (1.3-3.5) for in-hospital death. All RRs were adjusted for age and Hunt-Hess scores. Conclusions: ECG abnormalities assessed within 72 hours after SAH using a standard 12-lead ECG are independently associated with an increased risk of adverse clinical outcomes in patients with nontraumatic SAH.