Coronary Veins in a Sagittal Section of the Thorax, Lateral View

Description

Seen in left lateral profile through a sagittal section of the thorax, the heart sits anterior to the vertebral column and superior to the diaphragm, with the coronary venous system coursing over the epicardial surface toward the right atrium. Along the atrioventricular groove, the coronary sinus lies posterior and slightly inferior to the left atrium, receiving the great cardiac vein as it ascends from the anterior interventricular sulcus and the middle cardiac vein as it runs in the posterior interventricular sulcus. The small cardiac vein tracks along the right margin of the heart, while the oblique vein of the left atrium (vein of Marshall) may be appreciated on the posterior left atrial wall. Behind the cardiac silhouette, the esophagus descends posterior to the trachea toward the diaphragm, and the descending thoracic aorta parallels the vertebral bodies. A lateral sagittal cut clarifies why coronary veins are not just an afterthought to coronary arteries. Electrophysiology teams target the coronary sinus ostium for left ventricular lead placement in cardiac resynchronization therapy, and this approach depends on understanding the posterior location of the coronary sinus relative to the left atrium and its tributaries. The same anatomy underlies retrograde cardioplegia delivery during cardiac surgery, where malposition or anatomic variants can limit myocardial protection. Short and to the point. Venous pathways matter. Use this illustration for gross anatomy labs teaching pericardial relations, cardiothoracic surgery texts covering coronary sinus cannulation, and cardiology training materials on CRT lead navigation and venous anomalies in congenital heart disease. It also fits radiology correlation when interpreting cardiac CT or MR venography in a lateral or oblique plane. Anatomical accuracy verified by SciePro's Medical Advisory Board.