Swaminathan Neeraja, Chaudhary Siddique
Albert Einstein Medical Center, Philadelphia, USA.
Eur J Case Rep Intern Med. 2020 Mar 12;7(4):001482. doi: 10.12890/2020_001482. eCollection 2020.
Oesophageal varices are a dilated submucosal venous plexus in the lower third of the oesophagus which result from increased pressure in the portal venous system. The portal system is connected to the systemic circulation in specific locations referred to as sites of portosystemic anastomosis. An increase in portal venous pressure is therefore reflected at these anastomotic sites, causing manifestations such as oesophageal varices, rectal varices, caput medusae and splenorenal shunts. Varices do not cause symptoms until they leak or rupture and this is the main complication which requires prompt treatment. Here, we present a post-liver transplant patient with metastatic hepatocellular carcinoma who had oesophageal varices that fistularized with a left pulmonary vein, thus creating a right-to-left shunt. Right-to-left shunts are usually intracardiac or intrapulmonary in location. The complications of a right-to-left shunt include predominantly hypoxia, cyanosis and, sometimes, paradoxical emboli in the case of intracardiac shunts. This patient had a very uncommon cause of such a shunt caused by a direct fistulous connection.
Right-to-left shunts create a ventilation-perfusion mismatch.Recognizing situations where there is a connection between the systemic circulation and pulmonary circulation without intermediate oxygenation is important because of possible clinical implications such as hypoxia.
食管静脉曲张是食管下段扩张的黏膜下静脉丛，由门静脉系统压力升高引起。门静脉系统在特定部位与体循环相连，这些部位称为门体分流部位。因此，门静脉压力升高会在这些分流部位表现出来，导致食管静脉曲张、直肠静脉曲张、海蛇头和脾肾分流等表现。静脉曲张在破裂出血之前通常不会引起症状，而这是需要及时治疗的主要并发症。在此，我们报告一例肝移植术后发生转移性肝细胞癌的患者，其食管静脉曲张与左肺静脉形成瘘管，从而形成右向左分流。右向左分流通常发生在心脏内或肺内。右向左分流的并发症主要包括缺氧、发绀，心脏内分流时有时还会出现反常栓塞。该患者出现这种分流的原因非常罕见，是由直接瘘管连接所致。
右向左分流会导致通气-灌注不匹配。认识到体循环和肺循环之间存在直接连接且无中间氧合的情况很重要，因为这可能会产生如缺氧等临床影响。
