What is cardiac tamponade?
Cardiac tamponade is compression of the heart by rapid accumulation of fluid in its covering (pericardium). Accumulation of fluid in the pericardium is called pericardial effusion. It can occur due to various causes like infection, cancer, injury, inflammation etc. Cardiac tamponade can occur with small quantities of fluid if the collection progresses rapidly. But if it is a slow collection, larger amount of fluid is required to produce tamponade as the pericardium enlarges to accomodate more fluid when it collect slowly.
When the heart is compressed with fluid in the pericardial space, it is unable to receive blood from the rest of body when it relaxes (diastole). Hence it is unable to pump out much blood as well, as it is nearly empty at the end of relaxation phase. This leads to fall in blood pressure and breathlessness. It can be relieved rapidly in the hospital by aspirating fluid from the pericardial cavity and relieving the compression. After that investigations have to be done to find out the cause of fluid accumulation and the cause treated, to prevent re-accumulation of fluid and recurrence of cardiac tamponade. If cardiac tamponade is not promptly treated, it can lead to cardiac arrest (stoppage of the heart function) and death.