Nakashima Mitsutaka, Miki Takashi, Takaya Yoichi, Nakayama Rie, Nakagawa Koji, Akagi Satoshi, Toh Norihisa, Akagi Teiji, Ito Hiroshi
Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
J Cardiol Cases. 2022 Dec 7;27(3):124-127. doi: 10.1016/j.jccase.2022.11.005. eCollection 2023 Mar.
A 46-year-old woman with a history of repeated thromboembolic stroke and anti-phospholipid antibody syndrome was referred to our hospital. Saline contrast transthoracic echocardiography showed that microbubbles appeared in the left atrium within 4 heartbeats. Thus, she was initially suspected as having a patent foramen ovale with associated paradoxical embolism. However, no evidence of patent foramen ovale or atrial septal defect could be found using transesophageal echocardiography. Saline contrast transesophageal echocardiography showed that microbubbles flowed into the left atrium through the left superior pulmonary vein. Ultimately, she was diagnosed as having a pulmonary arteriovenous malformation located at the upper left pulmonary lobe using contrast computed tomography and pulmonary artery angiography. Pulmonary arteriovenous malformations are typically located in the lower lobe of either lung and, in bubble studies, contrast appears in the left atrium after 4 heartbeats. Here, the pulmonary arteriovenous malformation was in the upper lobe, and contrast appeared in the left atrium at an earlier time point: one associated with patent foramen ovale. These findings made it difficult to differentiate the two diseases initially. This case suggests that pulmonary arteriovenous malformation should be carefully considered, even if microbubbles appear in the left atrium early on a saline contrast transthoracic echocardiograph.
Pulmonary arteriovenous malformation occasionally appears in the upper lobe. In these cases, microbubbles may appear in the left atrium after detection in the right atrium with a time-course that is suggestive of a patent foramen ovale. Therefore, diagnosis should be carefully confirmed by using other multimodal imaging tests, such as transesophageal echocardiography, contrast computed tomography, or pulmonary artery angiography.
一名46岁有反复血栓栓塞性中风病史及抗磷脂抗体综合征的女性被转诊至我院。生理盐水对比剂经胸超声心动图显示在4个心动周期内左心房出现微泡。因此，她最初被怀疑患有卵圆孔未闭合并反常栓塞。然而，经食管超声心动图未发现卵圆孔未闭或房间隔缺损的证据。生理盐水对比剂经食管超声心动图显示微泡通过左上肺静脉流入左心房。最终，通过对比增强计算机断层扫描和肺动脉造影，她被诊断为左上肺叶存在肺动静脉畸形。肺动静脉畸形通常位于两肺的下叶，在气泡研究中，对比剂在4个心动周期后出现在左心房。在此病例中，肺动静脉畸形位于上叶，对比剂在更早的时间点出现在左心房：这一情况与卵圆孔未闭相关。这些发现使得最初难以区分这两种疾病。该病例提示，即使在生理盐水对比剂经胸超声心动图检查时微泡早期出现在左心房，也应仔细考虑肺动静脉畸形。
肺动静脉畸形偶尔会出现在上叶。在这些病例中，微泡可能在右心房被检测到后出现在左心房，其时间进程提示卵圆孔未闭。因此，应通过使用其他多模态成像检查，如经食管超声心动图、对比增强计算机断层扫描或肺动脉造影，仔细确认诊断。
