非外科手术瘢痕相关性右心房房性心动过速：电解剖标测与消融

Scar related right atrial macroreentrant tachycardia in patients without previous cardiac surgical inter- vention：electroanatomic mapping and catheter ablation

目的探讨非外科手术后的瘢痕相关性右心房房性心动过速（房速）的心内电生理和Carto三维电解剖标测特点及消融方法。方法2008年9月至2009年4月我中心诊治的14例无器质性心脏病基础的右心房房速患者，在Carto三维标测系统指导下行心内电生理检查、标测和射频消融。结果14例患者中有4例心内电生理检查和Carto电解剖标测符合右心房大折返性房速且在Carto电解剖电压标测中显示出“自发性瘢痕”，瘢痕分布于右心房游离壁。这4例患者年龄32～48岁，病史（23．40±15．43）个月，曾使用2种以上抗心律失常药物治疗无效。2例患者右心房轻至中度扩大，左心室射血分数均在正常范围，无明显器质性心脏病依据和心外科手术史及导管消融史。3例患者在瘢痕区内标测到缓慢传导的峡部，2例可诱发出三尖瓣峡部依赖性逆时针心房扑动（房扑）。在三尖瓣峡部、上腔静脉与瘢痕之间、下腔静脉与瘢痕之间、瘢痕与三尖瓣环之问，瘢痕与瘢痕之问或瘢痕区内缓慢传导的“峡部”进行线性消融。4例患者均即刻消融成功。随访（4．2±1．8）个月，3例未再发作心动过速，1例偶尔发作非持续性房速，服药控制良好。结论“自发性瘢痕”相关性右心房大折返性房速临床少见，三维电解剖电压标测可提高消融成功率。

Objective To explore the electrophysiologic and electroanatomic characteristics of unusual macroreentrant right atrial tachycardia in four patients with spontaneous atrial scarring. Methods From September 2008 to April 2009,14 patients with right atrial tachyeardia were treated with eleetrophysiologic studies and radiofroquency ablation using electroanatomic mapping in our center. Results Among the 14 patients, 4 patients（age 32- 48 years）had symptoms for（23.40 ±15.43 ）months who were resistant to more than two kinds of antiarrhythmic drugs. All 4 patients had overall normal systolic function, 2 mild right atrial enlargement. Scarring was present in the right atrial free wall. Right atrial central conduction obstacle was formed by an electrically silent area（ESA） in 3 patients. Stable circuits were through a ＂channel＂ within the scar in 2 patients, and typical cavotricuspid isthmus-dependent flutter in 2 patients. Radiofrequency ablation sites included the cavotricuspid isthmus, between the inferior vena cava and scar, tricuspid and scar,or a channel. Radiofrequency ablation of all inducible circuits was successful in all 4 patients. During the follow-up of（4. 2 ±1.8 ） months ,3 patients were free from macroreentrant atrial tachycardia. One had infrequent nonsustained macroreentrantt atrial tachycardia, and was controlled with previously ineffective medication. Conclusion Extensive spontaneous scarring of the atrium is an unusual cause of maeroreentrant right atrial tachycardias. Assisted with electroanatomic mapping,radiofrequency ablation is an effective treatment.