QT intervals and QT dispersion in patients with subarachnoid hemorrhage

Abstract

Purpose. To clarify the clinical significance of QT dispersion and the longest QT intervals (L-QTc) in patients with subarachnoid hemorrhage (SAH).

Methods. ECGs, clinical features, and laboratory data were analyzed in 38 patients with SAH (R) and 30 with unruptured cerebral aneurysms (U). Standard 12-lead ECGs obtained on admission were analyzed manually, and the longest QT interval (L-QTc) and the QT dispersion (difference between longest and shortest QTc) were compared between groups.

Results. There were no differences between groups R and U in age, sex, or location of aneurysms. The QT dispersion and L-QTc were greater in R than in U (109 ± 49 vs 64 ± 21 ms and 503 ± 63 vs 435 ± 38 ms, respectively; P < 0.01). The QT dispersion and L-QTc were longer in patients with premature ventricular contractions (PVCs) than in patients without PVCs (185 ± 30 vs 85 ± 41 ms and 586 ± 47 vs 467 ± 59 ms, respectively; P < 0.01). There were positive correlations between QT dispersion or L-QTc and preoperative Hunt and Hess grade (rs = 0.560 and rs = 0.615, respectively; P < 0.01). QT dispersion and L-QTc tended to correlate negatively with serum K⁺ (r = −0.365 and r = −0.376, respectively).

Conclusion. QT dispersion in patients with SAH is prolonged, especially in high-grade cases.