Acute Myocardial Infarction in the Elderly (1989)

To the Editor: — Regarding the excellent review by Dr Coodley,1 we wish to mention a study of acute myocardial infarction (AMI) in our country. Data was obtained from the study of 288 consecutive patients who were admitted to our hospital; 124 were 65 years or older (mean 72.5, Geriatric group: G), and 164 were younger (mean 53, control group: C). The relative rate of women was higher in “G,” with a male/female ratio of 2.1/1 vs 5.8/1. There was a higher proportion of painless infarction in “G” (13.7% vs 1.8%) similar to that described in other series,2-4 of atypical pain (18.7% vs 2.5%), of pain at rest (86% vs 61%) and pain of long duration (more than 6 hours, 34.6% vs 19.8%) (P < .001 for all these parameters). A high incidence of painless infarction was observed in diabetic elderly patients (24.1% vs 5.7% in nondiabetics, P < .01).5, 6 Elderly patients with chronic obstructive pulmonary disease had also very frequently a painless presentation in our series, 25% vs 7.5% (P < .001), a fact that could be explained by the frequent dyspnea or chest pain in these patients, which could mask coronary pain. Finally, elderly patients with atrial fibrillation also presented more painless infarctions (29.4% vs 8.2%, P < .01). Conversely, those patients with previous coronary disease had a lower number of painless presentations (3.8% vs 20.8%, P < .001); so we can postulate that the previous knowledge of the pain plays an important role. “G” showed more heart failure (44.3% vs 13.4%, P < .0001), hypotension (34.7% vs 9.1%, P <.0001) and shock (5.6% vs 2.4%, P < .01) after AMI. Furthermore, a higher proportion of postinfarction angina (45.2% vs 30%, P < .001) and extracardiac complications (51.6% vs 19.5%, P < .001) were detected. No intergroup differences were found in the maximum peak of CK nor in the time passed until it returned to normal values. There were more patients with LDH elevation in “G” (90.3% vs 74.4%, P < .001). Anterior AMI was the most frequent in “G” (57.2%) and diaphragmatic AMI in “C” (64%). New arrhythmias appeared more frequently in “G” (60.5%) vs 42.7%, P < .01), mainly accounted for by a higher proportion of atrial fibrillation (27.4% vs 4.3%, P < .001). Hypertension and diabetes were the most frequent risk factors in “G” (51.6% vs 30% and 43.5% vs 19.5% respectively, P < .0001) and smoking and high serum cholesterol in “C” (77.4% vs 50% and 35.5% vs 14.5% respectively, P < .001). Obesity was present in similar proportion in both groups. The overall in-hospital mortality was 16.1% in “G” and 8% in “C” (P < .01). Identical factors increased the mortality in both groups: heart failure, shock, certain arrhythmias (sinus bradycardia in “G” and multiple arrhythmias in “C” and extracardiac complications. No cardiovascular risk factors modified mortality significantly. The literature attributes a good prognosis to painless infarction, based on necropsy studies;7, 8 there was no significant difference in our series, although the trend was in the reverse direction, with mortality of 23.5% for painless infarction, 15% for the rest. The younger population admitted to the CCU had a lower mortality than those who remained on the ward (5.5% vs 23.8%, P < .001), but this reduction was not significant in “G” (14.6% vs 19%). There were no differences in the complications in patients treated in the CCU or on the ward (51 vs 52.40%). We conclude, as have other authors,9-12 that the clinical picture of AMI tends to be different in many respects among older compared to younger victims.