射频消融治疗起源于左室流出道的非持续性室性心动过速和频发性室性早搏

目的观察左室流出道非持续性室性心动过速（室速）和频发性室性早搏患者的射频消融治疗结果，探讨此类患者的射频消融指证。方法５例患者因非持续性室速和频发性室性早搏而引起明显临床症状，药物治疗无效。采用起搏标测法确定室速和室性早搏的起源部位，并射频消融治疗。结果在升主动脉瓣左窦下方的左室流出道记录到提前（３１±４）ｍｓ的心室激动，起搏心电图１２导联ＱＲＳ波形与室速和室性早搏形态完全相同者４例，１１导联相同者１例，该部位消融后５例患者的室速和室性早搏不被诱发。随访１３±６个月，除１例患者复发，另４例的临床症状明显改善。结论射频消融治疗左室流出道非持续性室速和室性早搏安全有效，但应严格掌握适应证。

Radiofrequency catheter ablation of nonsustained ventricular tachycardia and frequent ventricular premature contractions from left ventricular outflow tract

Objective To observe the results of radiofrequency catheter ablation for nonsustained ventricular tachycardia (NSuVT) and frequent premature ventricular contractions (PVCs) originating from left ventricular outflow tract,and also to discuss the indication for radiofrequency ablation. Methods Frequent severely symptomatic NSuVT and frequent PVCs in five patients were refractory to antiarrhythmic drugs.Radiofrequency catheter ablation was performed in these patients when the site of NSuVT and PVCs origin was identified with pace mapping technique. Results In all five patients,both NSuVT and PVCs shared the same electrocardiographic morphology,a pattern of atypical right bundle branch block with an inferior axis.From the site of left ventricular outflow tract just beneath the left coronary cusp of aortic valve,a local activation time 314 ms earlier than the onset of PVCs was recorded,and 12lead pace mapping demonstrated concordance with the NSuVT in 11(one patient) to 12 (four patients) ECG leads.NSuVT and PVCs were not inducible in all five patients after delivery of radiofrequency energy at this site.During a followup period of 136 months,NSuVT and PVCs recurred only in one patient,and the symptoms of the other four patients was singnificantly improved. Conclusion Radiofrequency catheter ablation is a safe and effective treatment for patients with nonsustained ventricular tachycardia and frequent premature ventricular contractions originating from left ventricular outflow tract.Appropriate selection of patients is very important.