Cheniti Ghassen, Glover Benedict M, Frontera Antonio, Denis Arnaud, Haissaguerre Michel, Derval Nicolas
Hôpital Cardiologique du Haut Lévêque, CHU Bordeaux, Pessac, France.
Heart Rhythm Service, Queen's University, Kingston, ON, Canada.
Eur Heart J Case Rep. 2018 Jul 13;2(3):yty078. doi: 10.1093/ehjcr/yty078. eCollection 2018 Sep.
Slow pathway (SP) ablation is considered to be the standard treatment for symptomatic atrioventricular nodal reentrant tachycardia (AVNRT). This may be challenging in patients with documented PR interval prolongation due to the potential increased risk of atrioventricular (AV) block in some patients.
We report two cases of symptomatic recurrent AVNRT refractory to medical treatment with significant baseline PR interval prolongation (304 ms and 336 ms). In both of these cases, the baseline electrophysiological study demonstrated dual AV nodal physiology with a functional antegrade fast pathway and evidence for transient normalization of the PR interval. Slow/fast AVNRT was confirmed in both cases. Slow pathway ablation was successfully performed resulting in normalization of the PR interval to 144 ms and 168 ms with no evidence of AV block. After a mean follow-up of 30 months, the patients remained asymptomatic with normal PR interval, no recurrence of AVNRT, and no documentation of high degree AV block.
Our cases illustrate a common dilemma when dealing with patients with AVNRT and prolonged baseline interval. We show that SP ablation is feasible and safe as long as a preserved antegrade FP is present.
慢径路（SP）消融被认为是有症状的房室结折返性心动过速（AVNRT）的标准治疗方法。对于有记录显示PR间期延长的患者，这可能具有挑战性，因为在某些患者中存在房室（AV）阻滞风险增加的可能性。
我们报告两例有症状的复发性AVNRT患者，药物治疗无效，基线PR间期显著延长（分别为304毫秒和336毫秒）。在这两例患者中，基线电生理研究均显示房室结双径路生理，存在功能性前向快径路，且PR间期有短暂正常化的证据。两例均确诊为慢快型AVNRT。成功进行了慢径路消融，PR间期恢复正常，分别为144毫秒和168毫秒，且无AV阻滞证据。平均随访30个月后，患者无症状，PR间期正常，无AVNRT复发，也无高度AV阻滞记录。
我们的病例说明了在处理AVNRT和基线间期延长的患者时常见的困境。我们表明，只要存在保留的前向快径路，SP消融是可行且安全的。
