Morady F, Kadish A, Rosenheck S, Calkins H, Kou W H, De Buitleir M, Sousa J
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.
J Am Coll Cardiol. 1991 Mar 1;17(3):678-89. doi: 10.1016/s0735-1097(10)80184-6.
Fifteen consecutive patients with drug-refractory, recurrent, sustained, monomorphic ventricular tachycardia and a history of remote myocardial infarction underwent catheter ablation of ventricular tachycardia. Shocks of 100 to 300 J were delivered to sites at which pacing during ventricular tachycardia resulted in concealed entrainment, in which the ventricular tachycardia accelerated to the pacing rate, there was a long stimulus to QRS interval and there was no change in the configuration of the QRS complex during pacing at several rates compared with the configuration during ventricular tachycardia, thus identifying a zone of slow conduction in the reentrant circuit. Concealed entrainment was demonstrated in nine (60%) of 15 patients, and the stimulus to QRS intervals were 90 to 400 ms. At sites of concealed entrainment, the endocardial activation time relative to the QRS complex during ventricular tachycardia ranged from -125 to +50 ms, the timing of the local electrogram relative to the QRS complex was the same during entrainment as during ventricular tachycardia and the pace map during sinus rhythm was discordant with that of the ventricular tachycardia in seven patients. In the six patients in whom a site of concealed entrainment could not be identified, the target site for ablation was selected on the basis of identification of an isolated mid-diastolic potential, activation mapping and pace mapping. The mean (+/- SD) cumulative number of joules delivered to the target site was 306 +/- 140. A successful long-term clinical outcome was achieved in 9 of the 15 patients (mean follow-up 20 +/- 7 months). The clinical success rate was the same whether the target site was selected on the basis of concealed entrainment (five of nine, 56%) or on the basis of the other mapping techniques (four of six, 67%). In conclusion, the responses to pacing suggest that sites at which there is concealed entrainment may be located within a zone of slow conduction in the ventricular tachycardia reentry circuit, although not necessarily in an area critical for the maintenance of reentry. The long-term clinical efficacy of catheter ablation targeted to sites of concealed entrainment is about 60%, similar to the results achieved when conventional mapping techniques are used.
15例患有药物难治性、复发性、持续性单形性室性心动过速且有陈旧性心肌梗死病史的连续患者接受了室性心动过速导管消融治疗。向室性心动过速时起搏导致隐匿性拖带的部位施加100至300焦耳的电击，隐匿性拖带是指室性心动过速加速至起搏频率，刺激至QRS间期延长，且在几种起搏频率下起搏时QRS波群形态与室性心动过速时相比无变化，从而确定折返环中的缓慢传导区。15例患者中有9例（60%）表现出隐匿性拖带，刺激至QRS间期为90至400毫秒。在隐匿性拖带部位，室性心动过速时相对于QRS波群的心内膜激动时间为-125至+50毫秒，拖带期间局部电图相对于QRS波群的时间与室性心动过速时相同，且7例患者窦性心律时的起搏标测与室性心动过速时不一致。在6例无法识别隐匿性拖带部位的患者中，根据孤立的舒张中期电位、激动标测和起搏标测来选择消融靶点。输送至靶点的平均（±标准差）累积焦耳数为306±140。15例患者中有9例（平均随访20±7个月）获得了成功的长期临床结果。无论靶点是根据隐匿性拖带（9例中的5例，56%）还是根据其他标测技术（6例中的4例，67%）来选择，临床成功率相同。总之，起搏反应表明，存在隐匿性拖带的部位可能位于室性心动过速折返环的缓慢传导区内，尽管不一定位于维持折返的关键区域。针对隐匿性拖带部位进行导管消融的长期临床疗效约为60%，与使用传统标测技术的结果相似。
