Microanatomy of the human coronary sinus and its major tributaries

Abstract

There are four separate intercommunicating systems of veins in the human heart: a) the system of the tributaries of the coronary sinus (c.s.); b) the system of the anterior cardiac veins; c) the system of atrial veins, and d) the system of Thebesian veins. The largest system is that of the tributaries of the c.s., which collects all the important cardiac veins — great, left marginal and/or posterior ventricular vein, middle and (in one-third of cases) small cardiac vein — and issues into the c.s. which empties into the right atrium (Figs. 1, 2). These veins drain, almost exclusively, the left ventricular myocardium [7]. This pattern of tributaries of the coronary sinus is called a pentade of large cardiac veins [13, 16], which is described and illustrated in textbooks and most anatomic atlases. Thus the c.s. is inserted between the systematic cardiac veins (except anterior cardiac veins) and the right atrium. Due to the concepts and experiments of Beck [2, 6] the c.s. seems anatomically to be the ideal location for the placement of a catheter for purposes of retrograde perfusion or other cardiological procedures [4, 6]. Retroperfusion techniques of the c.s. or regional cardiac veins are based on the generally assumed pattern in which 95% of the ventricular myocardium is drained by the c.s. tributaries. Such a relatively simple general organization does not however fully conform with reexamination in a large number of heart specimens. In fact, individual coronary venous systems feature a variety of anatomical configurations, demanding selective considerations and clinical adjustment of retrograde coronary venous interventions. In practical cardiology in 10%–20% of cases there is a failure of catheterization of the c.s. and cardiac veins [1], such as local subendocardial and mural hemorrhages, disturbances of the conduction system or even perforation of the atrial wall. On the strength of these experiences it is assumed that quite often the procedure of cannulation of the c.s. and cardiac veins is limited by anatomical variations, irregularities, anomalies, and malformations. A few of these, constituting a wide spectrum of variations will be demonstrated.