Hi, my son had open heart surgery on September 3rd 2013, and they replaced his mitral valve with a mechanical valve. He also had meningitis at the same time as the endocarditis. He has healed and has been home since October 5th. He is on blood thinners, which he takes daily. My question is: When he lays on his back he can push his stomach out, and it gets really big and round, and looks abnormal. Is this concerning?