Topography of the oblique vein of the left atrium (vein of Marshall)

Abstract

Background: The oblique vein of the left atrium is of interest for electrophysiologists working in the field of both basic science and clinical practice. Aims: We aimed to examine the topographic anatomy of the oblique vein and to assess the vein's location and relationships with surrounding cardiac structures. Methods: A total of 200 autopsied adult human hearts were examined. Results: The oblique vein was observed in 71% of the hearts. Its mean (SD) total length was 30.8 (13.6) mm. In hearts with the oblique vein, a larger distance was observed between the left inferior pulmonary vein (LIPV) and great cardiac vein (mean [SD], 18.6 [5.1] mm vs 16.3 [4.8] mm; P = 0.004), between the left atrial appendage (LAA) and LIPV (mean [SD], 17.8 [6.8] mm vs 15.1 [5.2] mm; P = 0.007), and between the LAA and left superior pulmonary vein (LSPV; mean [SD], 28.5 [7.2] mm vs 21.3 [6.4] mm; P <0.001). Hearts with a classic pattern of left.sided pulmonary veins were categorized into 4 types based on the length of oblique vein extension. In type I, the vein extended below the level of the LIPV (21.9%); in type II, to the level of the LIPV (47.7%); in type III, to the level of the interpulmonary area (17.2%); and in type IV, to the level of the LSPV (13.3%). In each type, the distance between the oblique vein and LIPV was shorter than that between the oblique vein and LAA. Conclusions: The oblique vein had a variable course and differing lengths of extension. The presence of the oblique vein was connected with a greater distance between the left-sided pulmonary veins and LAA.