Source:http://linkedlifedata.com/resource/umls/id/C1881170
NCI: Inappropriate sinus tachycardia (IST) is a rare form of supraventricular tachycardia involving the sinus node, in which a patient has an abnormally high heart rate, occurring both at rest and in response to stressors (such as physical activity).,NCI: Inappropriate sinus tachycardia (IST) is a rare form of supraventricular tachycardia involving the sinus node, in which a patient has an abnormally high heart rate, occurring both at rest and in response to stressors (such as physical activity). (NCI)