Panicker Gopi Krishna, Salvi Vaibhav, Karnad Dilip R, Chakraborty Saikat, Manohar Deepak, Lokhandwala Yash, Kothari Snehal
Quintiles Cardiac Safety Services, Mumbai, India.
Quintiles Cardiac Safety Services, Mumbai, India.
J Electrocardiol. 2014 Mar-Apr;47(2):155-7. doi: 10.1016/j.jelectrocard.2013.11.004. Epub 2013 Nov 27.
Lead II is commonly used to study drug-induced QT prolongation. Whether other ECG leads too show comparable QT prolongation is not known. We studied moxifloxacin-induced QT prolongation in a thorough QT study in healthy subjects (54 males, 43 females). Placebo-subtracted change from baseline in QTc corrected by Fridericia's method (ΔΔQTcF) at 1, 1.5, 2 and 4 hours after moxifloxacin was studied in all 12 leads. Unacceptably wide 90% confidence interval (CI) for ΔΔQTcF was seen in three leads; these leads also had maximum ECGs with flat T waves (60% in aVL, 45% in lead III and 42% in V1). After excluding ECGs with flat T waves, 90% lower CI of ΔΔQTcF was ≥ 5 ms in all leads except leads III, aVL and V1 in men. The 90% lower CI exceeded 5 ms in these leads in women despite wide 90% CIs because of greater mean ΔΔQTcF. Leads III, aVL and V1 should be avoided when measuring QT interval in thorough QT studies.
II导联常用于研究药物引起的QT间期延长。其他心电图导联是否也会出现类似的QT间期延长尚不清楚。我们在一项针对健康受试者（54名男性，43名女性）的全面QT研究中，研究了莫西沙星引起的QT间期延长。在莫西沙星给药后1、1.5、2和4小时，对所有12个导联采用弗里德里西亚法校正的QTc（ΔΔQTcF）从基线的安慰剂校正变化进行了研究。在三个导联中观察到ΔΔQTcF的90%置信区间（CI）宽得不可接受；这些导联的最大心电图还伴有T波平坦（aVL导联为60%，III导联为45%，V1导联为42%）。排除T波平坦的心电图后，除男性的III导联、aVL导联和V1导联外，所有导联的ΔΔQTcF的90%下限CI≥5 ms。尽管90%CI较宽，但由于平均ΔΔQTcF较大，女性这些导联的90%下限CI超过了5 ms。在全面QT研究中测量QT间期时，应避免使用III导联、aVL导联和V1导联。
