Clinical characteristics and outcome of elderly patients admitted in emergency department with an oxygen mismatch and type 2 myocardial infarction or myocardial injury.

BACKGROUND: Aging is a risk factor for type 2 myocardial infarction or myocardial injury, but few data are available on the elderly. We aimed to determine the factors associated with these pathologies and mortality in the elderly population and its age classes. METHODS: A retrospective cohort of all patients with oxygen mismatch (anemia, hypoxia, tachycardia, hypo/hypertension) for whom a troponin drawn was performed at admission in 2 emergency departments. Medical records were reviewed and classified as having type 2 myocardial infarction, acute or chronic myocardial injury, or no myocardial injury. RESULTS: Of the 824 patients who presented with oxygen mismatch, 675 (81.9%) were older than 65 years. Age over 85 years was a risk factor for acute non-ischemic myocardial injury (odds ratio, 95% confidence interval 2.23, 1.34-3.73). Non-ischemic myocardial injury was associated with hypoxemia, tachycardia, and acute renal failure in those older than 85 years, but only with acute infection in the 75-84-year-old group. Type 2 myocardial infarction was associated only with acute renal failure in the oldest group and, in the 75-84-year-old group, with acute heart failure and shock. Patients older than 85 years with acute myocardial injury, with or without infarction, had a higher in-hospital mortality, but subsequently, mortality depends more on the comorbidities than on age. CONCLUSION: Factors associated with type 2 myocardial infarction and acute non-ischemic myocardial injury in elderly admitted with oxygen mismatch vary notably between age classes. They are associated with in-hospital mortality but not with subsequent mortality when other cormorbities are taken into account.

Outcome of patients admitted with oxygen mismatch and myocardial injury or infarction in emergency departments.

AIMS: To describe the outcomes and associated factors in a population of patients admitted to emergency departments with at least one condition of oxygen supply/demand imbalance, regardless of the troponin result or restrictive criteria for type 2 myocardial infarction. METHODS: We constituted a retrospective cohort of 824 patients. Medical records of patients having undergone a troponin assay were reviewed for selection and classification, and data including in-hospital stay and readmissions were collected. The reported outcomes are in-hospital mortality, 3-year mortality, and major adverse cardiovascular events. RESULTS: Patients with myocardial infarction or injury, either chronic or acute, were older, with more history of hypertension and chronic heart or renal failure but not for other cardiovascular risk factors and medical history. Acute myocardial injury and type 2 myocardial infarction were significantly associated with in-hospital mortality [odds ratio (OR) 3.71 95% confidence interval (CI) 1.90-7.33 and OR 3.15 95% CI 1.59-6.28, respectively]. However, the long-term mortality does not differ in comparison with patients presenting chronic myocardial injury or nonelevated troponin, ranging from 26.9 to 34.3%. Patients with chronic myocardial injury and type 2 myocardial infarction had more long-term major cardiovascular events (39.3 and 38.8%), but only for acute heart failure, and none was associated with this outcome after adjustment. CONCLUSION: Among patients admitted to emergency departments with an oxygen supply/demand imbalance, acute myocardial injury and type 2 myocardial infarction are strongly associated with in-hospital mortality. However, they are not associated with higher long-term mortality or major cardiovascular events after discharge, which tend to occur in elderly people with comorbidities.