[Influence of in-hospital occurrence of organ failure on the prognosis of acute myocardial infarction in the elderly patients: an analysis of 2,535 cases].

Objective: To investigate the influence of in-hospital occurrence of organ failure on the prognosis of acute myocardial infarction (AMI) in 2 535 elderly patients of different age.

Methods: A total of 2,535 patients with AMI were divided into different age groups or outcome groups, and the outcome or the incidence of in-hospital complications were reviewed in different groups.

Results: (1)The rate of in-hospital death was higher in > or =80 years group (22.75%, 326/422) compared with that in 60-79 years group (12.26%, 1 854/2 113, chi (2)=42.15, P<0.01). (2)Compared with the survivors (1,854 cases, 27.1%, 17.4%, 7.5%, 4.5%, 4.5%, 40.3%, 9.1%), patients who died in hospital (259 cases) were more likely to have cardiogenic shock (44.0%), Killp II-III heart function (28.2%), respiratory failure (14.3%), stroke (11.2%), renal failure (11.2%), cardiac arrhythmia (49.8%), and anemia (14.7%) in 60-79 years group (all P<0.01). No difference in the rate of pulmonary infection (24.7% vs. 20.2%) and alimentary tract hemorrhage (5.8% vs. 3.9%) was found between two groups (both P>0.05). The incidence of cardiogenic shock (28.1%), Killp II-III heart function (32.3%), respiratory failure (17.7%), renal failure (16.7%), alimentary tract hemorrhage (10.4%), cardiac arrhythmia (49.0%) and anemia (21.9%) was higher in non-survival group (96 cases) than that in survival group (326 cases, 12.9%, 21.2%, 9.2%, 5.2%, 2.1%, 35.0%, 10.1%, P<0.05 or P<0.01) in patients> or =80 years. There was no difference in the incidence of stroke (11.4% vs. 5.8%) and pulmonary infection (32.3% vs. 23.3%) between two groups (both P>0.05). (3) The foremost four in-hospital complications in the non-survivors and survivors were cardiac arrhythmia, cardiogenic shock, Killp II-III heart function and pulmonary infection in 60-79 years group, but they were cardiac arrhythmia, pulmonary infection, Killp II-III heart function and cardiogenic shock in > or =80 years group. When compared the cases of in-hospital death between these two different age groups, the incidence of cardiogenic shock was significantly lower in the > or =80 years group (28.1% vs. 44.0%, P<0.01). However, the incidence of sudden death was higher in the > or =80 years group than that in 60-79 years group (22.92% vs. 7.34%, P<0.01).

Conclusion: The number and degree of in-hospital complications in elderly patients with AMI are increased by age. Cardiac arrhythmia is the major complication in elderly patients. For the patients 60-79 years old, it is more important to prevent and treat cardiogenic shock in order to improve the outcome in the 60-70 years group. In very old people with AMI, it is important to prevent sudden death.