Insular involvement in brain infarction increases risk for cardiac arrhythmia and death

Brain injuries may induce cardiac dysrhythmias and sudden cardiac death.

We analyzed 12-lead electrocardiograms of 493 consecutive patients with brain infarction (BI) proved by an magnetic resonance imaging and 493 control subjects matched for age, sex, and center. Insular involvement (insula (+/-)) was assessed by two independent readings of the magnetic resonance imaging scans. Cases were followed for 5 years.

Acute BI was independently associated with heart rate (< or = 64 beats/min), abnormal repolarization, atrial fibrillation, and ventricular and supraventricular ectopic beats. Lower heart rate in BI patients was due to an interaction with smoking (p for interaction = 0.004). Insula(+) group was significantly associated with abnormal repolarization with no interaction with infarct side. Atrial fibrillation by history was also more frequent in the insula(+) than in the insula(-) group (p = 0.07). After adjustment for age, sex, cardiovascular history, and handicap at admission, right insula(+) BI was significantly associated with 2-year all-cause death (hazard ratio, 2.11; 95% confidence interval, 1.27-3.52) and with vascular death (hazard ratio, 2.00; 95% confidence interval, 1.00-3.93). In multivariate analysis including age, sex, cardiovascular history, handicap at admission, and lesion side, increased QTc interval and left bundle branch block were independent predictors of all-cause and vascular mortality at 2 years in right insula(+) patients.

These findings support the notion that right insular involvement may lead to electrocardiographic abnormalities with potential prognostic implications. This could be important for optimal care in patients with right insular infarct.