Objectives: To determine the frequency of and risk factors for myocardial infarction (MI) in patients admitted to an ICU with GI hemorrhage, and the effects of MI on mortality and length of stay.
Methods: A retrospective review of the medical records of patients admitted to our ICU with GI hemorrhage was conducted. Charts were reviewed for various demographic, laboratory, and outcome parameters. Patients were categorized as having MI, not having MI, or inadequate data to allow classification.
Results: Two hundred thirty admissions to the ICU for GI hemorrhage were reviewed. One hundred thirteen cases had serial creatine phosphokinase (CK) measurements with isoenzymes allowing diagnosis of MI. In these 113 cases, patients' mean age was 67.4 ± 1.3 years and the mean APACHE II (acute physiology and chronic health evaluation) score was 10.9 ± 0.6. The in-hospital mortality rate was 13/113 (11.5%). Patients who did not survive had a higher admission APACHE II score (15.8 ± 2.0 vs 10.2 ± 0.5; p = 0.02), lower initial systolic BP (104.5 ± 4.4 vs 121.2 ± 3.2 mm Hg; p = 0.005), and a longer length of ICU stay (8.3 ± 1.8 vs 4.0 ± 0.4 days; p = 0.04) than those who survived. Sixteen of 113 patients met enzymatic and ECG criteria for MI. One patient complained of chest pain and nine of 16 had shortness of breath and/or dizziness. Patients with MI had significantly more cardiac risk factors (2.4 ± 0.2 vs 1.6 ± 0.1; p = 0.006), lower presenting hematocrit (26.0 ± 1.3 vs 30.5 ± 0.8; p = 0.007), and lower lowest hematocrit in the first 48 h (22.3 ± 0.9 vs 25.1 ± 0.6; p = 0.01), and tended to have a longer ICU stays (7.9 ± 2.2 vs 4.0 ± 0.4 days; p = 0.09) than those without MI. Patients who had MI were not more likely to die during hospitalization (risk ratio = 1.8; 95% confidence interval, 0.6 to 5.8).
Conclusions: Myocardial infarction occurs frequently in patients admitted to intensive care with GI hemorrhage. A clinical history of and multiple risk factors for coronary artery disease may help identify patients who are at increased risk of MI, which tends to be associated with a higher acuity of illness and in-hospital mortality. Prospective studies are required to further substantiate these associations.