Effect of improved door-to-balloon time on clinical outcomes in patients with ST segment elevation myocardial infarction.

OBJECTIVE: Few studies have focused on the effects of an improved door-to-balloon time on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to explore the effect of improving door-to-balloon time on prognosis and to identify major predictors of mortality.

METHODS: From January 2005 to December 2014, 1751 patients experienced STEMI and received primary percutaneous intervention in our hospital. During a 10-year period, the patients were divided into two groups according to the time period. Since mid-2009, shortening door-to-balloon time has been an important concern of health care. As a result of targeted efforts, as of January 2010, door-to-balloon time shortened significantly. In our study, a total 853 patients were in group 1 during January 2005 to December 2009, and a total 898 patients were in group 2 during January 2010 to December 2014.

RESULTS: The incidence of major adverse cardiac cerebral events (26.7% vs. 23.2%; p=0.120), the incidence of cardiovascular mortality (9.3% vs. 8.8%; p=0.741), and the incidence of all-cause mortality (12.6% vs. 12.2%; p=0.798) were similar between the two groups. The incidence of target vessel revascularization significantly decreased in group 2 (17.8% vs. 12.6%; p=0.008). However, the incidence of stroke increased in group 2 (1.8% vs. 3.6%; p=0.034).

CONCLUSION: Improving door-to-balloon time could not improve 1-year cardiovascular mortality whether low-risk or high-risk patients. The improvement in the door-balloon time does not improve outcomes studied, probably because it is not accompanied by a reduction in total reperfusion time, which means from onset of symptoms to reperfusion.