Anatomy of the coronary sinus with regard to cardiac resynchronization therapy implantation

Fig. 1. a The coronary sinus ostium and septal aspect of the right side of the heart seen from a superior view through the superior vena cava. Anteriorly is the tricuspid valve and the short distance between the valve and the coronary sinus can be appreciated. In b taken from the lateral side of the right ventricle, the relationship between the septal leaflet of the tricuspid valve and the coronary sinus ostium is more visible

Fig. 2. The outside of the infero-posterior aspect of the heart, showing the middle cardiac vein running in the interventricular groove, and the main coronary sinus (CS) running in the atrioventricular groove. The middle cardiac vein has a small apical side branch with an acute-angled take-off

Fig. 3. Schematic illustration of the coronary veins from a posterior view (a) and an anterior view (b). The asterisk represents a suitable lateral veinbranch where a lead can be placed. LSPV left superior pulmonary vein, LIPV left inferior pulmonary vein, LA left atrium, RSPV right superior pulmonary vein, RIPV right inferior pulmonary vein, IVC inferior vena cava, LV left ventricle, CS coronary sinus, LAA left atrial appendage, RV right ventricle

Fig. 4. Venograms from the right anterior oblique (RAO) and the left anterior oblique (LAO) views

Fig. 5. Preoperative cardiac computed tomography showing extreme enlargement of the right atrium, with the coronary sinus (CS) ostium in the usual position in the lower medial corner of the atrium. In such a case, a standard CS catheter often has insufficient support to enter the CS, and larger or stiffer sheaths need to be used

Fig. 6. Cardiac computed tomography showing the right atrium and ostium of the coronary sinus. There is contrast passage from the coronary sinus (CS) to the atrium, but the prominent Thebesian valve appears as a discontinuation of the CS right at the level of the ostium

Fig. 7. An example of difficult cannulation of the coronary sinus (CS) due to proximal stenosis and prominent Thebesian valve. By using a diagnostic electrophysiology catheter to pass through the initial part of the CS, keeping it “open,” a standard CS sheath can then be advanced in parallel to the EP catheter, gaining access for lead placement

Fig. 8. Difficult cannulation of an early side branch to the middle cardiac vein (MCV). The MCV take-off is highly angulated from the main coronary sinus, and there is another 90° turn to enter the side branch. An electrophysiology catheter and a subselect sheath are used for gaining access to the target vein (in this case, no other options were available due to no capture or phrenic nerve stimulation)

Fig. 9. Forceful contrast injection ends abruptly and fails to fill the more distal parts of the coronary sinus (CS) due to a prominent Vieussen’s valve, which obstructs retrograde passage through the main CS lumen

Fig. 10. A case with very tortuous anatomy of the only available (anterolateral) side branch. Small collaterals connected to the proximal main coronary (CS) trunk, and by using these for snaring, a left ventricular lead was successfully placed in a lateral position