[Clinical characteristics and hospital mortality of acute myocardial infarction in elderly patients treated with thrombolytic agents].

OBJECTIVES

This study describes the clinical features of elderly patients with acute myocardial infarction treated with thrombolytics and the effect of such therapy on in-hospital mortality rates in these patients.

METHODS AND RESULTS

A group of 463 consecutive patients older than 70 years with an acute myocardial infarction was studied. This population was divided into two groups: 157 patients who received thrombolytic therapy (group A) and 306 patients who did not (group B). Patients in group A were younger (77 vs 79 years; p = 0.01) and had a lower prevalence of females (32.5% vs 44.1%; p = 0.01), prior myocardial infarction (14% vs 28%; p = 0.0008), hypertension (38% vs 48%; p = 0.03), diabetes (17% vs 26%; p = 0.02), class Killip 3 at entry (3.5% vs 14%; p = 0.001), a higher frequency of Q wave MI (88% vs 50%; p = 0.0001), inferior location of MI (51% vs 32%; p = 0.00007) and Killip 1 (70% vs 57%; p = 0.01) compared to group B. No significant differences on the inhospital mortality between either group were observed (25.5% vs 24.8%; p = 0.88). However, the thrombolysis was associated with higher mortality in patients with left ventricular dysfunction at entry (41% vs 84%; p = 0.0008) and in those patients with a delay of more than four hours from the onset of symptoms to admission (19% versus 30%; p < 0.1).

CONCLUSIONS

1. In the elderly with acute myocardial infarction, thrombolytic therapy is administered to a lower risk population; 2) our findings do not confirm the benefits of chemical thrombolysis on cardiac mortality in the elderly, and 3) in selected subgroups (Killip > 2 at entry, symptoms delay > 4 hours) the risk/benefit ratio of thrombolytic therapy should be reevaluated. However, care needs to be taken in evaluating the data because this study was not blinded and the number of patients included was relatively small.