Hemopericardium refers to blood in the pericardial sac of the heart

Heart

The heart is a myogenic muscular organ found in all animals with a circulatory system , that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions...

. It is clinically similar to a pericardial effusion

Pericardial effusion

Pericardial effusion is an abnormal accumulation of fluid in the pericardial cavity. Because of the limited amount of space in the pericardial cavity, fluid accumulation will lead to an increased intrapericardial pressure and this can negatively affect heart function...

, and, depending on the volume and rapidity with which it develops, may cause cardiac tamponade

Cardiac tamponade

Cardiac tamponade, also known as pericardial tamponade, is an emergency condition in which fluid accumulates in the pericardium ....

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The condition can be caused by full-thickness necrosis (death) of the myocardium (heart muscle) after myocardial infarction, as well as trauma, and in patients receiving anticoagulants. Other causes include ruptured aneurysm of sinus of Valsalva

Aneurysm of sinus of Valsalva

Aneurysm of the aortic sinus, also known as the sinus of Valsalva, is comparatively rare. When present, it is usually in either the right or in the noncoronary sinus, rarely in the left Aneurysm of the aortic sinus, also known as the sinus of Valsalva, is comparatively rare. When present, it is...

 and other aneurysm

Aneurysm

An aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart...

s of the aortic arch

Aortic arch

The arch of the aorta or the transverse aortic arch is the part of the aorta that begins at the level of the upper border of the second sternocostal articulation of the right side, and runs at first upward, backward, and to the left in front of the trachea; it is then directed backward on the left...

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