Phillips, P.Sasadeus, J.Hodsman, G.Horowitz, J.Saltups, A.Johnston, C.2018-03-092018-03-091989Heart, 1989; 61(2):139-1430007-07691355-6037http://hdl.handle.net/2440/110935Published Online First: 01 Sep 1989.Plasma concentrations of immunoreactive atrial natriuretic peptide (mean (SEM] were measured in 135 patients admitted to two coronary care units with myocardial infarction, ischaemic chest pain, or non-ischaemic chest pain. Concentrations were significantly higher in patients with acute myocardial infarction not treated with systemic thrombolysis (60.4 (14.3) pg/ml) than in patients with non-ischaemic chest pain (21.1 (4.3) pg/ml). Patients with ischaemic chest pain had intermediate values (39.3 (7.1) pg/ml). Patients with acute myocardial infarction treated with intravenous streptokinase had normal concentrations of plasma atrial natriuretic peptide (20.2 (3.6) pg/mg), which were significantly lower than those in patients with myocardial infarction not given streptokinase. These changes could not be explained by factors such as age, pre-existing hypertension, renal dysfunction, or cardiac failure, nor treatment other than streptokinase. Raised plasma concentrations of atrial natriuretic peptide in acute myocardial infarction may be a homoeostatic response acting to reduce atrial pressures by natriuresis, diuresis, and venodilatation. The lower concentrations of atrial natriuretic peptide in patients with acute myocardial infarction treated with streptokinase may reflect a short term beneficial haemodynamic effect of streptokinase.enCopyright status unknownAtrial Natriuretic FactorJournal article003008203810.1136/hrt.61.2.1392-s2.0-0024503544396819Phillips, P. [0000-0002-9985-7631]Horowitz, J. [0000-0001-6883-0703]