11. Much like a mammalian heart, the avian heart is composed of endocardial , myocardial and epicardial layers. 12. Two endocardial tubes form here that fuse to form a primitive heart tube known as the tubular heart. 13. Endocardial cushion defects are associated with abnormalities of the atrioventricular valves ( the mitral valve and the tricuspid valve ).14. In this area, two separate angiogenic cell clusters form on either side and coalesce to form the endocardial tubes. 15. In some Nkx2.5 mutants, the cardiac tube is formed but the endocardial cushions and trabeculae are absent. 16. In January 2005, St . Jude Medical acquired Saint Paul, Minnesota-based Endocardial Solutions for $ 272 million. 17. Not every endocardial opening connects to the thebesian veins as some connect to the vessels of Wearn, which are arteries. 18. By the third week of embryological life, the endocardial tubes have developed a swelling in the part closest to the heart. 19. After the development of the SAN, the superior endocardial cushions begin to form a pacemaker as known as the atrioventricular node. 20. Therefore, the endocardial opening must be traced to a vein before it is definitely called an opening of the smallest cardiac veins.
