The pericardium is a double-walled sac that contains the heart and the roots of the great vessels. The outer wall of the pericardium is composed of dense connective tissue. The portion of the inner wall of the pericardium that is in contact with the heart (but not in contact with the great vessels) is the epicardium. The epicardium contains the blood vessels supplying blood to heart muscle (the coronary arteries) as well as nerve fibers.
It's been three years since the world learned of Michael Jackson's death. Photos: Remembering the King of Pop Three Years Later.
Michael Jackson may have been gone for five years now, but his legacy lives on through his music. Since his death, his estate have released two posthumous albums; 2010âs Michael, which peaked at Number 4 on the Official Albums Chart, and Xscape, which earned the singer his tenth UK Number 1 album last month.