心房颤动QT间期校正方法的探讨

Correlation of QT interval correction methods during atrial fibrillation and sinus rhythm

目的 探讨Bazett、Fridericia和Framingham3种公式对心房颤动QT间期校正的影响.方法 收集30例接受导管射频消融（CA）术的持续性心房颤动患者,以及与心房颤动患者年龄、性别匹配的20例阵发性室上性心动过速（PSVT）患者.收集CA术前、CA术后0.5h的心电图.测量连续3个心动周期QT间期.采用Bazett、Fridericia和Framingham 3种公式校正QT间期.每例患者CA术后的窦性心律维持均未使用抗心律失常药物和/或电复律.所有患者除外药物、严重冠状动脉缺血、近期电转复、电解质紊乱等影响心率校正QT间期的所有因素.结果 心房颤动患者CA术前和术后,心率差异无统计学意义[（89±15）次/min比（82±11）次/min,P=0.06].采用Bazett、Fridericia和Framingham公式校正QT间期,心房颤动患者和PSVT患者术后QTc与术前比较,差异均无统计学意义[心房颤动患者：（436±28） ms比（441±42） ms,P=0.398;（412±27） ms比（413±36） ms,P =0.887; （408±25） ms比（409±31）ms,P =0.762.PSVT患者：（436±17）ms比（437±14） ms,P=0.837;（411±16）ms比（421±13） ms,P=0.151;（412±14）ms比（422±12）ms,P=0.110].应用Bazett、Fridericia和Framingham公式分析心房颤动患者CA术前QTc与RR间期的相关性,相关系数分别为-0.399、-0.088、-0.031.结论 CA本身对QTc无影响.采用Bazett,Fridercia和Framingham 3种公式校正QT间期,持续性心房颤动患者CA术后的QTc无显著性改变.心房颤动患者采用Framingham公式校正QT间期受心动周期的影响更小.

Objective To compare the QT interval （QTc） during atrial tbrillation （AF）.Methods A total of 30 patients with persistent AF receiving catheter ablation （CA） were enrolled.We selected 20 sex-and agematched patients with paroxysmal supraventricular tachycardia（PSVT） who underwent CA.None of the patients had factors that might have impact on QT interval including drugs,severe ischemia,electrode disorders and recent cardioversion.QT interval was measured 1 day before CA under AF rhythm and immediate after CA under SR.At each measurement,at least 3 consecutive QRS complexes were taken.QTc was corrected with the cardiac cycle length and calculated using three formulas：Bazett,Fridericia and Framingham.Sinus rhythm （SR） was restored spontaneously by CA without applying any medication or cardioversion.Results Average heart rate was similar during AF and SR[（89 ± 15） times/min vs （82 ± 11） times/min,P =0.06].Regardless of the formula used to correct QT interval,a self-controlled comparison indicated that there was no signifcant difference of QTc before and after CA in patients with PSVT[（436 ± 17）ms vs （437 ± 14）ms,P =0.837; （411 ± 16）ms vs （421 ± 13）ms,P =0.151 ; （412 ± 14） ms vs （422 ± 12） ms,P =0.110] and there was no signifcant difference of QTc during AF and SR[（441 ±42）ms vs （436 ±28）ms,P =0.398;（412 ±27）ms vs （413 ±36）ms,P=0.887;（408 ±25）ms vs （409 ± 31）ms,P =0.762].However,during AF,QTc showed much less strong correlation coefficients with cardiac cycle length when assessed by Framingham formula （correlation coeffcients：-0.399,-0.088,-0.031）.Conclusions QTc during persistent AF is not different from that during SR when QT interval is corrected by using Bazett,Fridericia or Framingham formula.During AF,QTc is seldom influenced by cardiac cycle length when Framingham formula is applied.