Background: Atrial fibrillation (AF) occurs commonly in patients with acute myocardial infarction (MI) and is associated with an increased long-term mortality. This study aimed to investigate the clinical characteristics and outcomes of AF in in-hospital elderly Chinese patients with acute MI.
Methods: A total of 967 patients with acute MI, aged >/= 65 years, were categorized on the basis of the absence or presence of AF. Patients with documented AF were classified into two subgroups: the ongoing AF group and the new-onset AF group. We retrospectively evaluated the clinical profile, in-hospital outcomes, and effects of revascularization on the incidence of AF in elderly patients with acute MI.
Results: AF was documented in 100 (11.53%) patients and the incidence of new-onset AF was 6.51% during hospitalization. History of old MI and cerebrovascular events were more common in patients with AF than in those without AF (P < 0.001, P < 0.01, respectively). The incidence of AF was higher in patients with non-ST elevated MI (P = 0.014), inferior wall MI (P = 0.004) and cardiac function of Killip class III or IV (P = 0.008). Patients with AF had more complication of pneumonia (P = 0.003) and longer hospital stay. Left circumflex coronary artery involvement was more common in patients with AF (compared with patients without AF, P < 0.001). Percutaneous coronary intervention or coronary artery bypass grafting significantly decreased the incidence of new-onset AF from 7.97% to 3.82% (P = 0.017). AF depended to heart failure, increased the in-hospital mortality.
Conclusions: AF is common in elderly patients with acute MI and is associated with poorer clinical outcomes. Revascularization reduces the incidence of AF and thus improves the clinical outcomes in these patients.