A collection of fluid in the pericardium (sac around the heart). Such a collection, if it is large, may lead to a buildup of pressure on the heart. This often results in deterioration in its function, leading to low blood pressure or heart failure.
The recognized period either just before or just after a full cardiac arrest, when the patient’s condition is very unstable and care must be taken to prevent progression or regression into a full cardiac arrest.
A small hole between the atriums, related to failure of the normal Foramen Ovale to close completely after birth. Such a communication is present in about 20% of normal adults and very seldom causes any problem or requires treatment.