Atrioventricular block complicating inferior acute myocardial infarction treated with thrombolytic therapy

Objective To investigate the influence and mechanism of incidence of atriov entricular block (AVB) treated with thrombolytic therapy in acute inferior myocardial infarction (AIMI). Methods A total of 46 patients with AIMI were divided into the thrombolytic group (n = 23) and the nonthrombolytic group (n = 23). Intravenous or intr acoronary urokinase was given to the former group. We observed the advancin g courses of AVB, and further assessed the relationship between occurrence of AVB and stenosis of infarct-related artery (IRA) with coronary angiograp hy. Results Two cases died of III degrees AVB in the non-thrombolytic group, bu t none was found in the thrombolytic group. The occurrence rate of AVB was similar in both groups; but that of III degrees AVB was much lower in the t hrombolytic group (4 cases) than that in the non-thrombolytic group ( 11 ca ses, P < 0.05), and the duration of AVB decreased from 201 +/- 113 hours to 102 +/- 60 hours after thrombolytic therapy ( P < 0.01), which was mainly due to the decrease of AVB in the vanishing interval, but not in the develo ping interval. The coronary angiography demonstrated that there were an inc reasing reperfusion flow and a decreasing coronary stenosis of the infarct- related artery after thrombolytic therapy. Conclusion Thrombolytic therapy can reduce the incidence of severe AVB, sho rten its duration and decrease the mortality by increasing the coronary rep erfusion flow in the patients with AIMI.