Source:http://linkedlifedata.com/resource/umls/id/C0428977
MSH: Cardiac arrhythmias that are characterized by excessively slow HEART RATE, usually below 50 beats per minute in human adults. They can be classified broadly into SINOATRIAL NODE dysfunction and ATRIOVENTRICULAR BLOCK.,CSP: excessive slowness in the action of the heart, usually with a heart rate below 60 beats per minute.,NCI: Non-sinus origin slow heart rate.,NCI: An abnormally slow heartbeat; as applied in adult medicine, it is generally defined as a heart rate of under 60 beats per minute.