Noncoronary Heart Disease Department, Almazov National Medical Research Centre, Saint Petersburg, Russia.
Neuromodulation Laboratory, Almazov National Medical Research Centre, Saint Petersburg, Russia.
Biomed Res Int. 2020 Feb 17;2020:8919515. doi: 10.1155/2020/8919515. eCollection 2020.
Recently, transcatheter pulmonary artery (PA) ablation aiming at sympathetic denervation has been proposed in pulmonary arterial hypertension (PAH). This pilot feasibility study aimed to assess the feasibility of selective radiofrequency PA ablation based on response to high-frequency stimulation mapping.
The study comprised 3 female patients with idiopathic PAH (IPAH). The following reactions to PA stimulation were noted and marked by color points on the three-dimensional map: sinus bradycardia (heart rate decrease ≥15%), tachycardia (heart rate increase ≥15%), phrenic nerve capture, and cough. Since the most appropriate ablation strategy was unknown, two approaches were suggested, according to stimulation results: ablation at points with any heart rate response (either bradycardia or tachycardia)-this approach was applied in patient #1 (IPAH long-term responder to calcium channel blockers); segmental ablation at points with no response and with tachycardia response (one IPAH long-term responder to calcium channel blockers patient and one-IPAH with negative vasoreactive testing). Hemodynamic measurements were performed before and after denervation. Follow-up visits were scheduled at 6 and 12 months.
Six-months follow-up was uneventful for patients #1 and 3; patient #2 had one syncope and reduced 6-minute walk test distance and peak VO consumption. At 12 months, there was a normalization of mean PA pressure and pulmonary vascular resistance (PVR) in patient #1. Patient #2 had no change in PA pressure and PVR at 12 months. Patient #3 remained in II functional class; however, there was an increase in mean PA pressure and loss of vasoreactivity.
Electrical high-frequency stimulation of the PA identifies several types of evoked reactions: heart rate slowing, acceleration, phrenic nerve capture, and cough. The improvement in clinical and hemodynamic parameters following targeted PA ablation in the IPAH patient with positive vasoreactive testing should be confirmed in larger studies.
最近，针对肺动脉高压（PAH）的肺动脉（PA）消融术已被提出。这项初步可行性研究旨在评估基于高频刺激映射反应的选择性射频 PA 消融的可行性。
本研究纳入 3 名特发性 PAH（IPAH）女性患者。对 PA 刺激的以下反应进行了记录，并在三维地图上用彩点标记：窦性心动过缓（心率下降≥15%）、心动过速（心率增加≥15%）、膈神经捕获和咳嗽。由于不知道最合适的消融策略，根据刺激结果提出了两种方法：在有任何心率反应（心动过缓或心动过速）的部位进行消融-该方法应用于患者 #1（对钙通道阻滞剂长期有反应的 IPAH）；在无反应和心动过速反应的部位进行节段性消融（一名对钙通道阻滞剂长期有反应的 IPAH 患者和一名血管反应性测试阴性的 IPAH 患者）。在去神经支配前后进行血流动力学测量。随访时间为 6 个月和 12 个月。
患者 #1 和 #3 在 6 个月的随访中没有出现不良事件；患者 #2 出现一次晕厥，6 分钟步行测试距离和峰值 VO 消耗减少。在 12 个月时，患者 #1 的平均 PA 压和肺血管阻力（PVR）正常化。在 12 个月时，患者 #2 的 PA 压和 PVR 没有变化。患者 #3 仍处于 II 级功能状态；然而，平均 PA 压升高，血管反应性丧失。
PA 的高频电刺激可识别出几种诱发反应：心率减慢、加速、膈神经捕获和咳嗽。在对血管反应性阳性的 IPAH 患者进行靶向 PA 消融后，临床和血流动力学参数的改善应在更大的研究中得到证实。
