The long term impact of pre-hospital thrombolysis in acute myocardial infarction on the subsequent development of heart failure symptoms was investigated in 362 consecutive patients. The pre hospital strategy, used in 61 patients, allowed for very early administration of streptokinase, within 1.2±0.6 (mean±S.D.) hours from pain onset. In contrast, 294 patients treated in hospital received lytic treatment within 2.0±0.9 hours. The pre hospital group showed faster reperfusion, as measured by the time to peak creatine kinase and to ST segment recovery, but only a slightly better ventricular function, as compared to hospital treated patients. Heart failure symptoms were significantly reduced in the pre hospital group during hospitalization and at long term follow up: there were less dyspnea, fatigue, orthopnea, nocturnal dyspnea, nocturia, peripheral edema and episodes of pulmonary edema. Angina was reduced as well. We conclude that the initial benefit of prehospital thrombolysis translates into long term reduction of heart failure symptoms, thus improving quality of life.