Division Heart and Lungs, Department of Cardiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
Europace. 2013 Jan;15(1):144-9. doi: 10.1093/europace/eus171. Epub 2012 May 31.
Radiofrequency catheter ablation is a successful treatment for cardiac arrhythmias, but may lead to major complications such as permanent coronary damage. Irreversible electroporation (IRE) is a new non-thermal ablation modality, but its effect on coronary arteries is still unknown.
In a porcine model, epicardial IRE lesions were created at the base of the left ventricle in four hearts (group A) and directly on the left anterior descending artery (LAD) in five hearts (group B). After 3 weeks, coronary arteries inside IRE lesions and in apparently undamaged myocardium next to the lesions were (immuno-)histologically studied. Two untreated hearts served as controls. Coronary damage was defined as intimal hyperplasia. Left anterior descending artery angiograms were obtained before ablation, directly after ablation, and before termination in group B. In group A, 103 arterial branches were studied. Of these, 5 of 56 arterial branches inside lesions and 1 of 47 outside lesions showed intimal hyperplasia, but all had <50% area stenosis. Targeted LADs (group B) did not reveal intimal hyperplasia and angiograms showed no signs of stenosis. Expression of connective tissue growth factor was observed in the scar tissue, but not in the fibrotic tissue directly around the arteries, confirming that the arteries are indeed spared from tissue damage and remodelling.
Coronary arteries remain free of clinically relevant damage 3 weeks after epicardial IRE ablation, even amid very large myocardial lesions. This suggests that IRE ablation can be applied safely near or even on coronary arteries. With IRE ablation, arterial blood flow does not appear to affect lesion formation.
射频导管消融术是治疗心律失常的一种有效方法，但可能导致严重并发症，如永久性冠状动脉损伤。不可逆电穿孔（IRE）是一种新的非热消融方式，但它对冠状动脉的影响尚不清楚。
在猪模型中，在四个心脏（A 组）的左心室基底和五个心脏（B 组）的左前降支（LAD）上直接创建心外膜 IRE 病变。3 周后，在心外膜 IRE 病变内和病变附近明显未受损的心肌内对冠状动脉进行（免疫）组织学研究。两个未治疗的心脏作为对照。冠状动脉损伤定义为内膜增生。在 B 组中，在消融前、直接消融后和消融结束前获得左前降支血管造影。在 A 组中，研究了 103 个动脉分支。其中，5 个病变内的动脉分支和 47 个病变外的动脉分支显示内膜增生，但所有分支的狭窄面积均<50%。目标 LAD（B 组）未显示内膜增生，血管造影未显示狭窄迹象。在疤痕组织中观察到结缔组织生长因子的表达，但在动脉周围的纤维组织中没有观察到，这证实了动脉确实免受组织损伤和重塑的影响。
即使在心外膜 IRE 消融后形成非常大的心肌病变的情况下，冠状动脉在 3 周后仍未发生有临床意义的损伤。这表明 IRE 消融可在冠状动脉附近甚至在冠状动脉上安全应用。IRE 消融时，动脉血流似乎不会影响病变形成。
