Human heart has three layers, the outer one being pericardium. Pericardial sac is made of two thin layers of tissue that enclose our heart. Between the two layers is a small amount of fluid. This fluid keeps the layers from rubbing against each other and causing friction.
Cardiac tamponade or pericardial tamponade is a life threatening situation, where fluid (mostly blood) accumulates in the space between the pericardial sacs, faster than the pericardial sac can stretch. The outer pericardium is made of fibrous tissue which does not easily stretch, and so once fluid begins to enter the pericardial space, pressure starts to increase. This causes increase in pressure on the heart, thus preventing the proper filling of heart. The French verb "tamponner" means to plug up and, also, to smash into. Here the accumulating fluid within the pericardial sac is, so to speak, smashes into the heart. The end result, if untreated, is low blood pressure, shock and death.
Pericardial Tamponade Signs
Tamponade may present with symptoms of rapid breathing, difficulty in breathing, anxiety, restlessness, fainting, chest pain, palpitations. On examinations the blood pressure will be low, with decreased heart sounds.