Direct opening in the right atrium with
All veins of hea except the anterior cardiac veins and the venae cordis minimi drain into the coronary sinus which opens into the right atrium.The anterior cardiac veins and the venae cordis minimi open directly into the right atrium. BD CHAURASIA'S HUMAN ANATOMY .VOLUME 1.FIFTH EDITION.Page no-254
Anterior cardiac vein
Oblique vein
Middle cardiac vein
Great cardiac vein
Thorax