School of Health Science, First Department of Internal Medicine, Niigata University School of Medicine, Niigata, Japan.
J Cardiovasc Electrophysiol. 2012 Aug;23(8):877-80. doi: 10.1111/j.1540-8167.2012.02292.x. Epub 2012 Apr 11.
A 38-year-old woman with type 1 short-QT syndrome (SQTS) was referred to our hospital. Her ECG showed short QT/QTc interval and peaked T wave. Activation-recovery intervals (ARIs) were calculated from the intracardiac endocardial and epicardial electrode catheters placed in the left ventricle (LV). Intravenous administration of nifekalant prolonged effective refractory period at multiple ventricular sites as well as the QT/QTc interval (from 260/300 to 364/419 ms) on the surface ECG. Nifekalant also enlarged the transmural ARI dispersion of the ventricular repolarization, which was measured by the difference between the longest endocardial ARI and the shortest epicardial ARI during atrial pacing at 90 bpm, from 73 to 103-105 ms. These values corresponded to the intervals between the peak and end of the T wave on the surface ECG. Nifekalant-induced QT interval prolongation on the surface ECG may not indicate attenuation of the arrhythmogenic potential in the heart of SQTS patients.
一位 38 岁的 1 型短 QT 综合征（SQTS）女性患者被转至我院。她的心电图显示 QT/QTc 间期缩短和尖峰 T 波。激活-复极间期（ARIs）是从放置在左心室（LV）的心内膜和心外膜电极导管中计算得出的。静脉注射尼非卡兰延长了多个心室部位的有效不应期以及体表心电图上的 QT/QTc 间期（从 260/300 至 364/419ms）。尼非卡兰还扩大了心室复极的跨壁 ARI 离散度，这是通过在 90 次/分时心房起搏时测量最长心内膜 ARI 和最短心外膜 ARI 之间的差异来衡量的，从 73 至 103-105ms。这些值对应于体表心电图上 T 波峰和结束之间的间隔。尼非卡兰引起的体表心电图 QT 间期延长可能并不表明 SQTS 患者心脏的致心律失常潜能减弱。
