Beck's triad (cardiology)

Physiology

The rising central venous pressure is evidenced by distended jugular veins while in a non-supine position. It is caused by reduced diastolic filling of the right ventricle, due to pressure from the adjacent expanding pericardial sac. This results in a backup of fluid into the veins draining into the heart, most notably, the jugular veins. In severe hypovolemia, the neck veins may not be distended.

Clinical use

Although the full triad is present only in a minority of cases of acute cardiac tamponade, presence of the triad is considered pathognomonic for the condition.