Epinephrine-induced QT interval prolongation: a gene-specific paradoxical response in congenital long QT syndrome.
Epinephrine-induced QT interval prolongation: a gene-specific paradoxical response in congenital long QT syndrome.
复制标题
肾上腺素诱导的 QT 间期延长：先天性长 QT 综合征的基因特异性矛盾反应。
作者：
M. Ackerman;A. Khositseth;D. Tester;Joseph B Hejlik;W. Shen;C. J. Porter
客观化
目的：探讨肾上腺素对遗传型长QT综合征(LQTS)患者QT间期的影响。
患者和方法
1999年5月至2001年4月，来自21个不同家系的37例LQT患者(女性24例，其中LQT1 19例，LQT2 15例，LQT3 3例，平均年龄27岁，年龄10~53岁)和27例(女性16例，平均年龄31岁，范围13~45岁)在基线和递增剂量肾上腺素静脉注射(0.05，0.1，0.2和0.3微克×k(-1)×min(-1))时进行了研究。在每个研究阶段连续监测12导联心电图，测量心率、QT和校正QT间期(QTC)。
结果
LQTS患者和对照组在静息心率或肾上腺素变时性反应方面没有显著差异。LQTS患者平均+/-SD基线QTc值(500+/-68ms)大于对照组(436+/-19ms，P<0.01)。然而，19例KVLQT1基因分型的LQT1患者中有9例(47%)的静息QTc值大于460毫秒，而27名对照组中有11例(41%)的静息QTc值高于440毫秒。在肾上腺素注射期间，每个LQT1患者都表现出QT间期延长(矛盾反应)，而健康对照组和LQT2或LQT3患者倾向于QT间期缩短(P<；.001)。QT的最大平均+/-SD变化(AQT[肾上腺素QT减去基线QT])为-5+/-47ms(对照组)、+94+/-31ms(LQT1)和-87+/-67ms(LQT2和LQT3组)。在27名对照组中，有6名在大剂量肾上腺素治疗期间QT间期(AQT和GT；30毫秒)延长。小剂量肾上腺素(0.05微克×公斤(-1)×分钟(-1))完全区分LQT1患者(AQT，+82+/-34ms)和对照组(AQT，-7+/-13ms；P<；.001)。2例LQTS患者和1例对照组出现肾上腺素触发的非持续性室性心动过速。
结论
肾上腺素引起的QT间期延长似乎是LQT1的病因学特征。小剂量肾上腺素注射可将对照组与静息时QTC可疑的隐匿性LQT1患者区分开来。因此，肾上腺素刺激可能有助于揭开一些患有隐匿性LQTS的患者的面纱，并从战略上指导分子遗传学测试。
OBJECTIVE
To determine the effect of epinephrine on the QT interval in patients with genotyped long QT syndrome (LQTS).
PATIENTS AND METHODS
Between May 1999 and April 2001, 37 patients (24 females) with genotyped LQTS (19 LQT1, 15 LQT2, 3 LQT3, mean age, 27 years; range, 10-53 years) from 21 different kindreds and 27 (16 females) controls (mean age, 31 years; range, 13-45 years) were studied at baseline and during gradually increasing doses of intravenous epinephrine infusion (0.05, 0.1, 0.2, and 0.3 microg x k(-1) x min(-1)). The 12-lead electrocardiogram was monitored continuously, and heart rate, QT, and corrected QT interval (QTc) were measured during each study stage.
RESULTS
There was no significant difference in resting heart rate or chronotropic response to epinephrine between LQTS patients and controls. The mean +/- SD baseline QTc was greater in LQTS patients (500+/-68 ms) than in controls (436+/-19 ms, P<.001). However, 9 (47%) of 19 KVLQT1-genotyped LQT1 patients had a nondiagnostic resting QTc (<460 milliseconds), whereas 11 (41%) of 27 controls had a resting QTc higher than 440 milliseconds. During epinephrine infusion, every LQT1 patient manifested prolongation of the QT interval (paradoxical response), whereas healthy controls and patients with either LQT2 or LQT3 tended to have shortened QT intervals (P<.001). The maximum mean +/- SD change in QT (AQT [epinephrine QT minus baseline QT]) was -5+/-47 ms (controls), +94+/-31 ms (LQT1), and -87+/-67 ms (LQT2 and LQT3 patients). Of 27 controls, 6 had lengthening of their QT intervals (AQT >30 milliseconds) during high-dose epinephrine. Low-dose epinephrine (0.05 microg x kg(-1) x min(-1)) completely discriminated LQT1 patients (AQT, +82+/-34 ms) from controls (AQT, -7+/-13 ms; P<.001). Epinephrine-triggered nonsustained ventricular tachycardia occurred in 2 patients with LQTS and in 1 control.
CONCLUSIONS
Epinephrine-induced prolongation of the QT interval appears pathognomonic for LQT1. Low-dose epinephrine infusion distinguishes controls from patients with concealed LQT1 manifesting an equivocal QTc at rest. Thus, epinephrine provocation may help unmask some patients with concealed LQTS and strategically direct molecular genetic testing.
登录
查看更多内容
影响因子：
9.4
作者：
Ketty Lehmann;Philippe Schwartz;Raffaella Bloise Coumel;Clive Wattanasirichaigoon;Wilhelm Corbett;
通讯作者：
Ketty Lehmann;Philippe Schwartz;Raffaella Bloise Coumel;Clive Wattanasirichaigoon;Wilhelm Corbett;
影响因子：
2.8
作者：
Moss, AJ;Robinson, JL;Timothy, K
通讯作者：
Timothy, K
影响因子：
37.8
作者：
Moss, AJ;Zareba, W;Andrews, ML
通讯作者：
Andrews, ML
DOI：
10.1016/s0735-1097(99)00582-3
发表时间：
2000-03-01
影响因子：
24
作者：
Shimizu, W;Antzelevitch, C
通讯作者：
Antzelevitch, C
影响因子：
1.3
作者：
Shimizu, W;Antzelevitch, C
通讯作者：
Antzelevitch, C