心房后间隔局灶性房性心动过速的电生理特征及射频消融

目的 探讨起源于心房后间隔及邻近区域局灶性房性心动过速（房速）心脏电生理特点及射频导管消融特点.方法 入选23例患者,男12例,女11例,平均年龄（48.3±19.3）岁,自发或心房程序刺激诱发房速后,分析体表心电图P＆#39;波特点并于后间隔各个部位进行激动标测和射频消融治疗.结果 23例心房刺激均能反复诱发或终止房速,平均周长（346.7±61.8） ms,房速时P＆#39;波时限明显短于窦性心律时P波时限（86.2±14.0）ms对（115.4±19.9） ms,P＜0.05].体表P＆#39;波表现为Ⅰ导联多呈等电位线,下壁导联呈深倒负向波,aVR和aVL导联呈正向波,V3～W5导联呈负向波.常规激动标测,所有患者于冠状静脉窦口（CSO）附近标测到相对提前的心房激动,其中12例起源于右后间隔,6例起源于CSO及近端,2例起源于心中静脉,3例起源于左后间隔.靶点提前体表P＆#39;波平均（34.4±18.0） ms,放电开始至心动过速终止时间为（6.2±4.2）s,11例患者放电过程中出现交界区心律.所有患者均消融成功,其中3例需应用盐水灌注导管.随访4个月～ 10年,无复发病例及手术相关并发症.结论 后间隔局灶性房速P＆#39;波形态具有特异性,对导管消融定位意义较大.由于解剖的复杂性,部分病例标测和消融困难,需结合右心房后间隔、冠状静脉窦（CS）内和/或其分支、左心房后间隔等多部位标测和/或消融方能获得成功.

Electrophysiologic characteristics and radiofrequency catheter ablation of focal atrial tachycardia in posterior septum and nearby region

Objective To investigate the electrocardiographic and electrophysiological characteristics and the effect of radiofrequency catheter ablation of focal atrial tachycardia（FAT） in posterior septum（PS） and nearby region.Methods Twenty-three consecutive patients （11 females,mean age 48.3 ± 19.3 years） with paroxysmal FAT originating from PS and nearby region were included.The surface electrocardiogram features of FAT were analyzed and activation mapping was performed during FAT to identify the earliest activation sites in PS and adjacent sites.Radiofrequency catheter ablation （RFCA） was delivered at the site with earliest activation.Results The average cycle length of FAT was （346.7±61.8） ms.The P＆#39; wave duration during FAT was significantly shorter than that during sinus rhythm （86.2± 14.0） ms vs.（115.4± 19.9） ms,P〈0.05）].The P＆#39;wave morphologies were nearly isoelectric in lead Ⅰ,deeply negative in all inferior leads,positive in lead aVR and aVL,negative in lead V3-V5.Activation mapping in the right atrium showed that the site with earlier atrial activation was located close to the PS.Successful ablation was achieved in all the 23 patients.FATs were eliminated by RFCA in right PS（RPS） in 12 patients,coronary sinus（CS） ostium or proximal CS in 6 patients,middle cardiac vein in 2 patients,left PS（LPS） in the rest 3 patients.The earliest atrial activation time at the target sites preceded the onset of surface P＆#39; wave by （34.4± 18.0）ms.It took about （6.2±4.2） s to successfully ablate FAT.Junctional rhythm occurred in 11 patients during ablation.Long-term success was achieved in all patients during a period of 4 months to 10 years follow-up without complications.Conclusion The P＆#39; wave morphologies of FAT originating from PS could be helpful to locate the origins.Sometimes mapping and ablation of FAT adjacent to the area were very diffficult.Combination of mapping and ablation in RPS,within the CS and its branch,or in LPS was important to eliminate FAT of PS in some patients.