Veldtman Gruschen R, Wilson Gregory J, Peirone Alejandro, Hartley Amanda, Estrada Marvin, Norgard Gunnar, Leung Ramsey K, Visram Naheed, Benson Lee N
Department of Pediatrics, Division of Cardiology, Hospital for Sick Children, University of Toronto School of Medicine, Ontario, Canada.
Catheter Cardiovasc Interv. 2005 Aug;65(4):556-63. doi: 10.1002/ccd.20328.
Perforating radiofrequency (PRF) energy has been used to obtain percutaneous transseptal left heart access. Contrary to ablative radiofrequency (RF), myocardial tissue responses to PRF thermal injury are incompletely defined. In this study, a newly developed RF catheter system for transseptal left atrial entry was compared with conventional needle puncture. Of 15 piglets having transfemoral cardiac catheterization, 12 had transseptal procedures. Needle punctures (NP) and PRF were followed by acute (1 hr; 3 NP, 3 PRF) and chronic necropsy (1 month; 3 NP, 3 PRF). The remaining three piglets had intentional RF aortic perforation through the atrial roof with necropsy at 1 month. Gross and histopathological effects were examined. Acutely, the gross RF lesion was similar to needle puncture. Histologically, the RF lesions had minimal mural thrombus, an inner zone of thermal injury characterized by grayish cytoplasmic staining (elastic trichrome), and a bubbly transformation of the cytoplasm in innermost cardiomyocytes, partial persistence of cross-striations, and an acute inflammatory reaction. The outer extent of the lesion (< 1 mm) was defined by a halo of contraction band necrosis similar to needle puncture. Acute NP injury showed comparable depth and extent of myocyte necrosis (principally contraction bands) with adjacent tissue hemorrhage and edema. At 1 month, a well-developed densely collagenous scar was present in both aortic and transseptal PRF lesions. The extent of acute RF injury is similar to that seen in conventional NP, but the characteristics of tissue insult are different. Both show well-developed healing at 1 month.
穿孔射频（PRF）能量已被用于经皮经间隔进入左心。与消融射频（RF）不同，心肌组织对PRF热损伤的反应尚未完全明确。在本研究中，将一种新开发的用于经间隔进入左心房的射频导管系统与传统针刺进行了比较。在15只接受经股动脉心脏导管插入术的仔猪中，12只进行了经间隔操作。针刺（NP）和PRF后分别进行急性（1小时；3只NP，3只PRF）和慢性尸检（1个月；3只NP，3只PRF）。其余三只仔猪通过心房顶部进行了有意的射频主动脉穿孔，并在1个月时进行了尸检。检查了大体和组织病理学效应。急性时，射频大体病变与针刺相似。组织学上，射频病变有最小的壁血栓，热损伤的内层以灰色细胞质染色（弹性三色染色）为特征，最内层心肌细胞的细胞质有气泡样改变，横纹部分持续存在，并有急性炎症反应。病变的外部范围（<1mm）由类似于针刺的收缩带坏死晕圈界定。急性NP损伤显示出与相邻组织出血和水肿相当的心肌细胞坏死深度和范围（主要是收缩带）。在1个月时，主动脉和经间隔PRF病变中均出现了发育良好的致密胶原瘢痕。急性射频损伤的程度与传统NP相似，但组织损伤特征不同。两者在1个月时均显示出良好的愈合。
