Objective: To evaluate the clinical features and outcomes in patients suffering from acute myocardial infarction combined with elevated serum creatinine.
Methods: We enrolled 340 consecutive patients suffering from acute myocardial infarction admitted into our hospital from 2003.2.1 - 2004.8.31. The patients were divided into the following 2 groups, 269 patients in a group with normal serum creatinine and 71 patients in a group with elevated serum creatinine, according to the normal limit of serum creatinine in our hospital. Outcomes during hospitalization were available in all the patients and one year follow-up data were also available in all the patients. The influence of baseline demographic and clinical variables on mortality at day 30 and one year during the follow-up period was evaluated by Cox proportional hazard regression to determine the independent predictors of late adverse events.
Results: Elevated creatinine at baseline was present in 71 of the 340 patients. Compared with patients with normal creatinine, patients with elevated creatinine were older and more likely to have old myocardial infarction and to present with cardiac shock, heart failure, ventricular fibrillation and complete AVB. Mortality was markedly increased in patients with baseline elevated creatinine as compared with these without at day 30 (32.39% versus 4.83%, P = 0.000), during hospitalization (35.21% versus 5.20%, P = 0.000) and at 1 year (43.66% versus 11.15%, P = 0.000). By Cox regression analysis, elevated creatinine was a powerful independent hazard predictor of 30-day survival (odds ratio 4.591, 95% confidence interval 2.149 to 9.808, P = 0.000) and remained to be associated with reduced survival at 1 year (odds ratio 3.936, 95% confidence interval 2.264 to 6.845, P = 0.000).
Conclusions: Baseline elevated creatinine is associated with a markedly increased risk of 30-day death, death during hospitalization and mortality at one year in patients suffering from acute myocardial infarction and may be an independent risk factor of prognosis of acute myocardial infarction.