Acute Myocardial Infarction in the Elderly

pp. 426-433

Abstract

Summary

Elderly patients suffering an acute myocardial infarction (AMI) constitute a particular sub-group with a high mortality rate.

Objective

Comparison of clinical, epidemiological and therapeutic aspects of AMI in the elderly.

Methods

We conducted a retrospective study on 551 patients (pts) (mean age 62 ± 12 years, 80% males) admitted to the CCU consecutively with AMI during the period 1995-2000. Elderly (E) pts were defined as those >_ 75 years old and young (Y) pts were those younger than 75 years old.

Results

E pts were 93 (17%). Mean age was 81 (75-85)for the E and 60 (52-67) for the Y group. In the E group a higher prevalence of females 841% vs, 15%; p < 0.0001), previous chronic angina(18% vs 10%; p < 0.002) prior infarction (25% vs 14%; p = 0.02) and less smoking habit (15% vs 56%; p < 0.0001) were observed. Type of infarction, treatment and evolution: E evidenced a lower incidence of Q-wave infarction(63% vs 78%; p < 0.002) but higher incidence of non Q-wave subendocardial infarction (15% vs 2.4%; p < 0.0001), anterior location (53% vs 40%; p = 0.02) and Killip class > 1 at admission (49.5%vs 20%; p < 0.0001). The use of thrombolytics was lower in the E (17% vs 42.5%; p < 0.0001) and the use of primary angioplasty was similar in both groups (13% in the E vs 10% in theY; p = ns). A multivariate analysis of the whole population pointed to some parameters as in-dependent predictive variables of absence of thrombolytics usage: age >: 75 yrs (OR 0.3, 95%CI 0.15-0.60; p = 0.0005), admission after > 6 hs of AMI (OR 0.12 95% CI 0.07-0.2; p < 0.0001), prior infarction (OR 0.5 95% CI 0.3-1; p = 0.04) and prodromal progressive angina (OR 0.3 95% CI0.1-0.8; p = 0.01). In addition, the only independent variable for direct angioplasty was Killip class > 1 at admission (OR 5 95% CI 2.7-9.5; p =0.001). Mortality: mortality rates were higher in the E, as expected (30% vs 8.6%; p < 0.0001). Predictive variables of mortality -in the multi-variate analysis performed in the overall population- were: age _> 75 years (OR 2.1 95% CI 1-4.4; p = 0.05), female gender (OR 2.4 95% CI 1.2-4.7; p = 0.01) and Killip class > 1 at admission(OR 8.4 95% CI 4.5-15; p < 0.00001). In addition, among the E, female gender (OR 2.7 95% CI 1-6.5; p = 0.03), subendocardial infarction (OR 5.295% CI 1.5-18; p = 0.009) and Killip class > 1 at admission (OR 4 95% CI 1.4-12; p = 0.008) were the strongest predictors of mortality.

Conclusions

Elderly patients suffering AMI constitute a high risk mortality group due to a higher prevalence of females, more extensive coronary artery disease, prior ventricular dysfunction and heart failure during the AMI. An adequate stratification of the clinical risk profile of the E suffering AMI is needed in order to optimize the use of reperfusion strategies.