Whitwam Wayne, Rule Stephen, Narayan Sanjiv M
University of California San Diego, San Diego, CA 92161, USA.
Heart Rhythm. 2007 Jul;4(7):959-63. doi: 10.1016/j.hrthm.2007.01.026. Epub 2007 Feb 1.
Idiopathic right ventricular tachycardia typically originates from the right ventricular outflow tract (RVOT). However, it also may originate from above the pulmonic valve. We describe a patient with a 2-year history of symptoms of palpitations associated with premature ventricular contractions (PVCs) in whom radiofrequency catheter ablation at the PVC exit site in the lateral RVOT failed despite the presence of several favorable criteria. However, using a multiple electrode array catheter, we demonstrated above the pulmonic valve clear evidence of low-amplitude preceding electrical activity ("blue ghost") that swept 3 cm inferolaterally over 20 ms to the previously identified lateral RVOT exit. Catheter mapping even at 128x gain demonstrated only very-low-amplitude potentials at this site, and pacing was unable to capture the ventricle from this region. However, ablation at this site immediately terminated the arrhythmia, and the patient has remained PVC-free after 1 year. This case supports the existence of previously hypothesized myocardial sleeves above the pulmonary valve that may be responsible for RVOT tachycardia and shows that they can be detected using noncontact mapping.
特发性右心室心动过速通常起源于右心室流出道（RVOT）。然而，它也可能起源于肺动脉瓣上方。我们描述了一名有2年心悸症状病史且伴有室性早搏（PVC）的患者，尽管存在几个有利标准，但在RVOT外侧PVC出口部位进行射频导管消融仍失败。然而，使用多电极阵列导管，我们在肺动脉瓣上方证实了低振幅前电活动（“蓝影”）的明确证据，该电活动在20毫秒内向下外侧扫过3厘米至先前确定的RVOT外侧出口。即使在128倍增益下进行导管标测，在该部位也仅显示出极低振幅的电位，并且起搏无法从该区域夺获心室。然而，在此部位进行消融立即终止了心律失常，该患者在1年后仍无PVC。此病例支持了先前假设的肺动脉瓣上方心肌袖套的存在，其可能是RVOT心动过速的原因，并表明使用非接触标测可以检测到它们。
