左后分支型特发性左心室室性心动过速消融后心电轴改变与否对左心室形态及功能的影响

Effects of cardiac axis changes after catheter ablation on the morphology and function of the left ventricle in patients with idiopathic left posterior fascicular ventricular tachycardia

目的 以经胸和组织多普勒超声心动图评价左后分支型特发性左心室室性心动过速（ILVT）导管消融术后心电轴改变与否对左心室形态、功能及室壁运动协调性的影响.方法 2003年4月至2007年6月在沈阳军区总医院行射频导管消融术的连续32例ILVT患者,男22例,女10例,平均年龄（30±16）岁.电生理检查明确ILVT诊断后,通过标测ILVT时最早的浦肯野电位（PP）或舒张期电位（DP）处做为消融靶点.根据消融后体表心电图是否出现心电轴改变,将患者分为2组.比较2组术前及术后随访过程中超声心动图检查结果,且在13例患者中比较心脏组织多普勒超声检查结果.结果 32例ILVT患者均经导管消融成功.消融术后未发生心电轴改变者21例,心电轴明显改变者11例.术后随访17.3～95.0（35.1±17.5）个月.消融术前和术后左心室舒张末期内径（LVEDD）和左心室射血分数（LVEF）在发生心电轴改变者LVEDD：（44.0±6.5）mm对（41.1±5.9） mm;LVEF：0.65±0.06对0.60±0.05未发生心电轴改变者LVEDD：（45.0±4.5）mm对（41.6±4.0） mm;LVEF：0.67±0.06对0.61±0.04,差异无统计学意义（P＞0.05）.心脏组织超声检查组共入选13例患者,其中消融术后心电轴未发生和发生改变者分别为7例和6例,消融术前和术后相比较,室壁各阶段收缩期平均速度差异无统计学意义（P＞0.05）.结论 ILVT消融术后所产生的心电轴明显改变,不影响左心室功能、形态及室壁运动整体协调性.

Objective The purpose of this study was to investigate whether the change of the cardiac axis after catheter ablation would affect the morphology and function of the left ventricle in patients with idiopathic left posterior fascicular ventricular tachycardia （ILVT）.Methods Thirty-two patients [22 male;mean age （30 ± 16）years] underwent radiofrequency catheter ablation of ILVT were enrolled in this study.Catheter ablation targeted the earliest Purkinje potential （PP） or the diastolic potential（DP） recorded along the posterior or middle left ventricular septum during ILVT.The end point of ablation was that ILVT could not be reinduced after ablation.The patients were divided into two groups according to whether there was cardiac axis change examined by the surface ECG after ablation.The findings of surface ECG and echocardiography were compared before and after ablation and during the period of follow-up.In addition,cardiac tissue echocardiography was examined before and after ablation among 13 consecutive patients.Results All the patients underwent successful catheter ablation.In 11 of the 32 patients,ablation resulted in significant cardiac axis change or left posterior fascicular block.After a mean follow-up period of 35.1±17.5 （range from 17.3 to 95.0） months,there were no significant differences in left ventricular end-diastolic diameter（LVEDD） and left ventricular ejection fraction （LVEF） before and after ablation among patients with [LVEDD：（44.0 ± 6.5） mm vs.（41.1 ± 5.9）mm; LVEF：0.65 ± 0.06 vs.0.60±0.05 ; n =11] or without [LVEDD：（45.0 ± 4.5） mm vs.（41.6 ±4.0） mm; LVEF：0.67 ± 0.06vs.0.61±0.04;n=22] cardiac axis change（P〉0.05）.There were not significant changes of the mean systolic speed of the left ventricular walls measured by tissue echocardiography both in patients with or without cardiac axis change.Condusion The obvious change of cardiac axis after catheter ablation in patients with ILVT might have no harmful effect on the morphology and function of the left ventricle in a long term.