频发右心室流出道室性期前收缩对右心室流出道结构影响的研究

目的 探讨右心室流出道(RVOT)起源频发室性期前收缩对RVOT结构的影响.方法 选取2009～2011年行射频消融治疗的频发RVOT起源室性期前收缩患者30例,分析其心电图特征、动态心电图、心脏彩色超声结果及术中精确定位,分析室性期前收缩对RVOT结构的影响.结果 射频消融术前RVOT直径为(31.76±3.33)mm,术后6个月为(30.93±2.68)mm(P＜0.01)；相关性分析显示:RVOT直径与室性期前收缩负荷呈正相关(r=0.484,P＜0.05).RVOT间隔部来源室性期前收缩QRS时限为(157.69±18.33) ms,游离壁来源室性期前收缩QRS时限为(179.23±16.05)ms(P＜0.01),QRS时限与来源部位相关(r=0.566,P＜0.01).室性期前收缩QRS时限与RVOT直径无相关性(r=0.097,P＞0.05).结论 RVOT来源室性期前收缩经射频消融治疗后,RVOT直径有减小的趋势,其与室性期前收缩负荷呈正相关,与室性期前收缩形态无相关性.

Effect of frequent idiopathic ventricular premature contractions from right ventricular outflow tract on structure of right ventricular outflow tract

Objective To investigate the effect of frequent ventricular premature contractions（VPCs） from right ventricular outflow tract（RVOT） on the structure of right ventricular outflow tract.Methods 30 patients with frequent VPCs from RVOT who underwent radiofrequency ablation from 2009 to 2011 were enrolled.The site of origin of VPCs was identified by the characters of ECG according to the stepwise electrocardiographic algorithm and the accurate anatomical location was identified by 3D electroanatomical non-contact mapping.Parameters of haemodynamic were accessed by means of transthoracic echocardiography before and 6 months after intervention.The average daily amount of VPCs was evaluated by Holter and the ECG characters of VPCs were also analyzed.Results Before and 6 months after intervention,the diameter of RVOT was（31.76±3.33） mm and（30.93±2.68） mm（P0.01）.Correlation analysis showed that the diameter of RVOT correlated positively with the average daily amount of VPCs（r=0.484,P0.05）.Duration of QRS complex of VPCs from septa of RVOT was（157.69±18.33） ms,and that of VPCs from free wall of RVOT was（179.23±16.05） ms.Positive correlation was found between the duration of QRS complex of VPCs and the RVOT site of origin（r=0.566,P0.01）.No correlations were found between the diameter of RVOT and the ECG character of VPCs or the RVOT site of origin of VPCs（r=0.097,P0.05）.Conclusion The diameter of RVOT decreased after radiofrequency ablation for the patients with VPCs from RVOT and it correlated positively with the average daily amount of VPCs.