Cryptogenic Stroke Caused by Pulmonary Arterial Venous Malformation with Massive Right-to-Left Shunt: A Case Report

Jie Zhan; Cong Dong; Mei Li; Lechang Zhan; Hongxia Chen; Liming Lu; Jianhua Liu

doi:10.1007/s40120-021-00275-y

Cryptogenic Stroke Caused by Pulmonary Arterial Venous Malformation with Massive Right-to-Left Shunt: A Case Report

Neurol Ther. 2021 Dec;10(2):1135-1142. doi: 10.1007/s40120-021-00275-y. Epub 2021 Sep 3.

Authors

Jie Zhan^{1

2}, Cong Dong², Mei Li², Lechang Zhan², Hongxia Chen², Liming Lu³, Jianhua Liu⁴

Affiliations

¹ Postdoctoral research station, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China.
² Department of Rehabilitation, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, 510120, China.
³ Clinical Research and Data Center, South China Research Center for Acupuncture and Moxibustion, Medical College of Acu-Moxi and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, 510120, China. lulimingleon@126.com.
⁴ Research Team for Acupuncture Effect and Mechanism, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China. jyhf08@sina.com.

Abstract

Background: Pulmonary arterial venous malformation (PAVM) is an abnormal vascular malformation between pulmonary arteries and veins characterized by varying degrees of right-to-left shunts (RLS). Cryptogenic stroke (CS) due to paradoxical embolism (PE) caused by PAVM is relatively rare in the clinic.

Case presentation: We report the case of a 54-year-old right-handed woman who presented with sudden-onset left-sided limb weakness for 2 h. A physical examination revealed normal vital signs but weakness in her left upper and lower limbs, graded as 1/5 using the Medical Research Council scale. Her National Institutes of Health Stroke Scale (NIHSS) score was 8, and her modified Rankin scale (mRS) was 4. Brain diffusion-weighted imaging showed acute infarction in the right basal ganglia and the radiation crown but brain magnetic resonance angiography found no obvious abnormality. A transcranial Doppler ultrasound with bubble study (TCD-b) found the rain curtain sign of microbubbles in the left middle cerebral artery, reflecting significant RLS. Transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) were conducted to distinguish between intra- and extracardiac shunts. A pulmonary computerized tomography angiogram (CTA) demonstrated a PAVM. We considered the patient had CS due to PE caused by PAVM. Thrombolytic therapy within the time window was performed. Then, transcatheter device occlusion of the arteriovenous fistula was successfully undertaken, and the patient carried on with rehabilitation training. At a 15-month follow-up, there were no catheter-related complications or recurrent stroke, and her NIHSS and mRS scores were both 0.

Conclusions: PAVM is an important risk factor for PE and CS and should not be ignored as a possible etiology in stroke patients without any other risk factors. CTA of the pulmonary artery is the recommended gold standard for diagnosing and locating a PAVM. Thrombolytic therapy within the time window combined with transcatheter device occlusion of arteriovenous malformation and rehabilitation training may benefit the recovery of patients with CS caused by PE resulting from PAVM.

Keywords: Case report; Cryptogenic stroke; Paradoxical embolism; Pulmonary arterial venous malformation; Right-to-left shunt.