[Subacute morphologic changes in the heart after radiofrequency ablation in the area of the atrioventricular...

Catheter ablation of the atrioventricular (AV) junction for due to refractory supraventricular tachycardias by means of the radiofrequency (RF) current is at present an accepted and widespread mode of therapy. Although pathomorphological findings of the early postablative period are well documented in animals, only few data are available on pathological postablative changes in humans. In this paper we present the necropsy findings in a woman who suddenly died 25 days after RF ablation of AV junction. In this case the ablative procedure has caused subendocardial necrosis revealing signs of advanced organisation with deposits of lipofuscin and haemosiderin. We have also found the necrosis of fat tissue in the vicinity of the tricuspid anulus in the stage of advanced resorption. The recent complication was the thrombotic occlusion of a small branch of coronary artery in the right atrial posterior wall causing a nonextensive acute infarction. We conclude that our findings are in agreement with the literature data on morphologic similarity of ablative lesions and reparative processes in experimental models and clinical practice. (Fig. 4, Ref. 8.)