Day C P, McComb J M, Campbell R W
Department of Academic Cardiology, Freeman Hospital, Newcastle upon Tyne.
Br Heart J. 1990 Jun;63(6):342-4. doi: 10.1136/hrt.63.6.342.
Homogeneity of recovery time protects against arrhythmias whereas dispersion of recovery time is arrhythmogenic. A single surface electrocardiographic QT interval gives no information on recovery time dispersion but the difference between the maximum and minimum body surface QT interval may be relevant. This hypothesis was tested by measuring the dispersion of the corrected QT interval (QTc) in 10 patients with an arrhythmogenic long QT interval (Romano Ward and Jervell and Lange-Nielsen syndromes or drug arrhythmogenicity) and in 14 patients without arrhythmias in whom the QT interval was prolonged by sotalol. QTc dispersion was significantly greater in the arrhythmogenic QT group than in the sotalol QT group. In patients with prolonged QT intervals, QT dispersion distinguished between those with ventricular arrhythmias and those without. This supports the hypothesis that QT dispersion reflects spatial differences in myocardial recovery time. QT dispersion may be useful in the assessment of both arrhythmia risk and the efficacy of antiarrhythmic drugs.
恢复时间的均一性可预防心律失常，而恢复时间的离散度则会引发心律失常。单次体表心电图QT间期无法提供有关恢复时间离散度的信息，但体表QT间期最大值与最小值之间的差异可能具有相关性。通过测量10例患有致心律失常性长QT间期（罗曼诺-沃德综合征、耶韦尔和朗格-尼尔森综合征或药物致心律失常性）的患者以及14例无心律失常但因索他洛尔导致QT间期延长的患者的校正QT间期（QTc）离散度，对这一假设进行了验证。致心律失常性QT组的QTc离散度显著高于索他洛尔QT组。在QT间期延长的患者中，QT离散度可区分有无室性心律失常的患者。这支持了QT离散度反映心肌恢复时间空间差异的假设。QT离散度可能有助于评估心律失常风险和抗心律失常药物的疗效。
