Significance of temporary pacemakers insertion in patients with acute myocardial infarction

Objective. Indication of temporary pacemakers in patients during acute myoc ardial infarction was widely studied in the pre-thrombolytic era without ha ving determined whether the generalization of fibrinolysis might have chang ed the overall incidence and significance of temporary. pacemakers. Our aim was to determine the incidence and the prognostic significance of insertio n of temporary pacemakers in patients with acute myocardial infarction. Patients and methods. In a study involving 1,239 patients consecutively adm itted to hospital with acute myocardial infarction we studied clinical char acteristics and prognosis depending on temporary pacemaker insertion or not . We performed an univariate analysis on in-hospital mortality and those se lected variables were introduced in to a logistic regression analysis. Results. A temporary pacemaker was indicated in 55 patients (4.4%), prophyl actically in 22% and therapeutically in 78%. Temporary pacemakers were inse rted in 55% of the patients with advanced AV block and in the 10% of the pa tients with bundle-branch block. Pacemaker insertion was associated with hi gher number of affected leads in the ECG, and higher CK peak, regardless of the association with thrombolysis. The following complications were more o ften observed in patients with temporary pacemakers: atrial fibrillation, h eart failure, right bundle-branch block, advanced atrioventricular block an d in-hospital mortality (45.4 vs 10.2%; p < 0.001). Need for a temporay pac emaker was less frequent in patients treated with thrombolytics; compared w ith those not treated (3.0 vs 6.1%; p < 0.02). Pacemaker insertion had an i ndependent value for predicting in-hospital mortality (OR 5.51; 95% Cl, 2.7 1-11.19). Conclusion. The insertion of a temporary pacemaker in acute myocardial infa rction is less frequent nowdays than on the pre-thrombolytic era. Pacemaker insertion is associated with higher indices of infarct extension and in-ho spital mortality, having independent prognostic value on the in-hospital mo rtality.