Partial anomalous pulmonary venous return: more common from the left or right lung?

Abstract

Dear editor, I read with great interest ‘‘Anatomical study of partial anomalous pulmonary venous return with special references to the bronchial vein: supplementary report’’ (Okamoto et al. 2008). They describe an anomalous right upper lobe vein draining into the superior vena cava. They note that this is the most frequent type of partial anomalous pulmonary venous return. While previous studies corroborate this statement (Brody 1942; Snellen et al. 1968), a more recent study examining the prevalence of partial anomalous pulmonary venous return using computed tomography provides conflicting data. In this study, 79% had an anomalous left upper lobe vein draining into a persistent left vertical vein, 17% had a right upper lobe vein draining into the superior vena cava, and 3% had a right lower lobe vein draining into the suprahepatic inferior vena cava (Haramati et al. 2003). This difference in prevalence may partially be due to easier detection of left upper lobe anomalous veins than right upper lobe anomalous veins with computed tomography (Haramati et al. 2003). However, the patient population studied may also be a factor. Prior studies reporting partial anomalous pulmonary venous return were mostly autopsy series or surgical reports of a young population with cardiac defects. These data may not apply to the adult population. The recent study utilizing computed tomography was performed in an adult population, and suggests that the characteristics of partial anomalous pulmonary venous return may differ in pediatric and adult populations.