Ventricular fibrillation is one type of arrhythmia that can be deadly. It occurs when the heart beats with rapid, erratic electrical impulses. This causes pumping chambers in your heart (the ventricles) to quiver uselessly instead of pumping blood. Without an effective heartbeat, blood pressure plummets, cutting off blood supply to your vital organs.
In the ABO system, (and Rhesus D system) all blood belongs to one of four major groups: A+/â, B+/â, AB+/â, or O+/â. The presence (+) or absence (â) of the RhD (Rhesus D) antigen is indicated by the plus or minus following the ABO type. But there are more than two hundred minor blood groups that can complicate blood transfusions. These are known as rare blood types.
Our blood types are determined by heredity. People belong to either of eight different blood types: A Rh+, A Rh-, B Rh+, B Rh-, AB RH+, AB Rh-, 0 Rh+, or 0 Rh- . The eight blood types have different combinations of certain molecules, antigens, on the surface of the red blood cells. The A and B antigens are sugars and the Rh antigens are proteins. The antigens expressed in the red blood cells determine an individual's blood type. Also the combination of some other molecules floating around in the blood plasma differs between the eight blood types, the so called antibodies.