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

BACKGROUND: The oblique vein of the left atrium is of interest for both basic and clinical electrophysiologists. AIMS: We aimed to examine topographic anatomy of oblique vein and focus on assessing vein's location and relationships with surrounding heart structures. METHODS: There were 200 autopsied adult human hearts examined. RESULTS: The oblique vein was observed in 71.0% and had total length of 30.8 (13.6) mm. In hearts with present oblique vein, significantly larger distances were observed between left inferior pulmonary vein (LIPV) and great cardiac vein as well as between left atrial appendage (LAA) and left inferior and superior pulmonary veins (18.6 [5.1] vs. 16.3 [4.8] mm, P = 0.004; 17.8 [6.8] vs. 15.1 [5.2] mm, P = 0.007; and 28.5 [7.2] vs. 21.3 [6.4] mm, P < 0.001, respectively). Hearts with classic pattern of left-sided pulmonary veins were categorized into four types based on the length of oblique vein extension. In type I, the vein extended below the level of LIPV (21.9%); in type II, to the level of LIPV (47.7%); in type III, to the level of interpulmonary area (17.2%); and in type IV, to the level of left superior pulmonary vein (13.3%). In each type, the distance between oblique vein and LIPV was shorter than the distance between oblique vein and LAA. CONCLUSIONS: The oblique vein had a variable course and differing lengths of extensions, which were classified into four distinct types. Presence of an oblique vein was associated with larger distances between left-sided pulmonary veins and LAA.