[Impact of admission heart rate on in-hospital mortality in patients with acute myocardial infarction].

Objective: To evaluate the impact of admission heart rate (HR) on in-hospital mortality in patients with acute myocardial infarction.

Method: The data of 904 in-hospital patients with ST-elevation myocardial infarction were collected from database of Beijing Anzhen Hospital during 2003--2004. The patients were divided into three groups according to the admission HR: < 80 beats/min, 80 - 90 beats/min and > 90 beats/min. Left ventricular ejection fraction (LVEF), left ventricular end diastolic dimension (LVEDD), left ventricular end systolic dimension (LVESD) and the cases of in-hospital death were analyzed.

Result: (1) Age, gender, smoking, hypertension, diabetes, the number of diseased vessel detected by coronary angiography were similar among three groups. LVEDD in group > 90 beats/min [(51.9 +/- 7.5) mm] and group 80 - 90 beats/min [(51.6 +/- 5.8) mm] were significantly larger compared with group < 80 beats/min [(50.3 +/- 5.3) mm, all P < 0.05]; LVESD in group > 90 beats/min [(39.5 +/- 8.7) mm] were also significantly increased compared with group 80 - 90 beats/min [(37.1 +/- 7.1) mm] and group < 80 beats/min [(34.8 +/- 6.2) mm, all P < 0.05]; LVEF was significantly lower in group > 90 beats/min (46.0% +/- 10.6%) compared with group 80 - 90 beats/min (49.5% +/- 11.3%) and group < 80 beats/min (54.6% +/- 10.8%, all P < 0.05). In-hospital mortality was significantly higher in group > 90 beats/min (18.2%) than those in group 80 - 90 beats/min and in group < 80 beats/min (8.5%, 3.9%, all P < 0.05). (2) Multivariate analysis showed that admission HR was an independent risk factor for in-hospital mortality (OR = 1.025, 95% CI 1.008 - 1.043, P = 0.005).

Conclusion: The high level of admission HR was a powerful predictor of in-hospital mortality and ventricular remodeling in patients with acute myocardial infarction.