<unk><unk>  of the<unk>  (AV)<unk>  is a rare benign congenital<unk> . The origin of the<unk><unk>  of the AV<unk>  is still controversial. Although it is called mesothelioma of the AV<unk> , it appears to have endodermal origin. The size of the<unk>  ranges from 0.5 mm to 30 mm and size of the<unk>  is not correlated with the occurrence of fatal arrhythmias. On gross pathology, small multiocular cysts are characteristic findings of the<unk><unk>  of the AV<unk> . On microscopic examination, solid cell nests and<unk>  structures lined by flattended cuboidal and squamous epithelium mixed with rare neuroendocrine cells (C cells) are characteristic findings of the<unk><unk>  of the AV<unk> . The immunohistochemical staining of the<unk><unk>  of the AV<unk>  is in favor of the epithelial differentiation of the<unk> .<unk><unk>  of the AV<unk>  is most commonly diagnosed postmortem in individuals died due to sudden cardiac death. Fatal arrhythmias including ventricular tachycardia or ventricular fibrillation may occur despite pacemaker placement. Only a few cases of<unk><unk>  of the AV<unk>  has been diagnosed antemortem. Imaging modalities including echocardiography and MRI are helpful in making the diagnosis. Histopathological examination of the resected<unk>  provides the definitive diagnosis. Because of the critical location of the<unk>  and its unfavorable prognosis, surgical excision is the mainstay of treatment for<unk><unk>  of the AV<unk> . Anti-arrhythmic drugs and lifelong pacemaker placement may be necessary after excision to manage any post-surgical AV block.
Cystic Tumor of the Atrioventricular Node
Echogenic intracardiac focus
Sinoatrial nodal reentry tachycardia
Wandering atrial pacemaker
Aneurysm of sinus of valsalva
Post-infarction conduction abnormalities
Pacemaker mediated tachycardia
Postinfarction conduction abnormalities