Endovascular embolization of pulmonary arteriovenous malformations

Abstract

Background: The major consequence of pulmonary arteriovenous malformations (PAVMs) is the direct inflow of blood from the pulmonary artery to the pulmonary vein which induces hypoxemia. Severe complications include transient ischemic attacks, paradoxical embolization in the central nervous system, massive hemoptysis or hemothorax, etc. The conventional treatment is surgical intervention. However, this can be very traumatic and dangerous. Endovascular embolization has advantages over surgery such as a faithful therapeutic effect, a low complication rate, repeatability, etc.

Methods: Patients (n = 23) with symptomatic PAVMs underwent endovascular embolization; 11 were males and 12 were females, with ages ranging from 6 months to 58 years. During the embolization, microcoils were applied in 6 cases and standard steel coils were used in 17 cases.

Results: Multiple PAVMs lesions were found in 16 cases and single PAVMs lesion was found in 7 cases. Embolotherapy was carried out 28 times for 23 patients. The success rate was 100%. The results of pulmonary arteriography after treatment showed that single lesion disappeared completely while the main abnormal vessels in multiple lesions also disappeared. The mean blood oxygen saturation increased from (78.04 + or - 8.22)% to (95.13 + or - 3.67)% after the procedure. A correlated groups t test showed changes in blood oxygen saturation before and after embolization (t = 9.101, P < 0.001). Symptoms of cardiac insufficiency disappeared in 5 cases and vascular murmur in the chest disappeared in 13 cases. After embolization, mild chest pain occurred in 11 cases, small amounts of pleural effusion occurred in 5 cases, and 1 patient died 2 months later because of a pyogenic infection secondary to the pulmonary infarction. Among the 22 remaining cases, with overall follow-up ranging from 18 months to 12 years, general conditions were fine, daily lives were normal and there were no neurologic symptoms or signs, except for 3 patients with diffused PAVMs who had persistent blood oxygen saturation between 85% and 90%. Symptoms of hypoxia never recurred in the other cases.

Conclusions: Endovascular embolization of pulmonary arteriovenous malformations can significantly improve blood oxygen saturation and reduce serious complications such as cerebral infaction. Therefore, this kind of interventional procedure is a safe and effective treatment method with a low complication rate.