The QT dispersion and QTc dispersion in patients presenting with acute neurological events and its impact on early prognosis

J Neurosci Rural Pract. 2016 Jan-Mar;7(1):61-6. doi: 10.4103/0976-3147.172173.

Abstract

Aims: To find out and investigate whether the QT dispersion and QTc dispersion is related to type and prognosis of the acute stroke in patients presenting within 24 h of the onset of stroke.

Settings and design: This was a observational study conducted at Mahatma Gandhi Hospital, Dr. SN. Medical College, Jodhpur, during January 2014 to January 2015.

Subjects and methods: The patients presented within 24 h of onset of acute stroke (hemorrhagic, infarction, or transient ischemic event) were included in the study. The stroke was confirmed by computed tomography scan and magnetic resonance imaging. Patients with (i) altered sensorium because of metabolic, infective, seizures, trauma, or tumor; (ii) prior history of cardiovascular disease, electrocardiographic abnormalities' because of dyselectrolytemia; and (iii) and patients who were on drugs (antiarrhythmic drugs, antipsychotic drugs, erythromycin, theophylline, etc.,) which known to cause electrocardiogram changes, were excluded from the study. National Institute of Health Stroke Score (NIHSS) was calculated at the time of admission and Modified Rankin Scale (MRS) at the time of discharge. Fifty age- and sex-matched healthy controls included.

Statistical analysis used: Student's t-test, ANOVA, and area under curve for sensitivity and specificity for the test.

Results: We included 52 patients (male/female: 27/25) and 50 controls (26/24). The mean age of patients was 63.17 ± 08.90 years. Of total patients, infarct was found in 32 (61.53%), hemorrhage in 18 (34.61%), transient ischemic attack (TIA) in 1 (1.9%), and subarachnoid hemorrhage in 1 (1.9%) patient. The QT dispersion and QTc dispersion were significantly higher in cases as compare to controls. (87.30 ± 24.42 vs. 49.60 ± 08.79 ms; P < 0.001) and (97.53 ± 27.36 vs. 56.28 ± 09.86 ms; P < 0.001). Among various types of stroke, the mean QT dispersion and QTc dispersion were maximum and significantly higher in hemorrhagic stroke as compared to infarct and TIA (P < 0.001). The mean QT dispersion and QTc dispersion was found significantly high in nonsurvivors (n = 16) as compared to survivors group (n = 36) (P < 0.05). The mean QT dispersion was directly correlated with the NIHSS and functional outcome score MRS. Patients with greater QT and QTc dispersion having high NIHSS had poor prognosis.

Conclusion: We concluded that patients presenting with acute neurological events having increased QT dispersion and QTc dispersion is related to high mortality and poor functional outcomes on hospital discharge and if the values of dispersion score are very high we can predict for hemorrhagic stroke.

Keywords: Acute stroke; QT dispersion; hemorrhage; infarct; prognosis.