Abstract: （Abstract）Objective: To observe the clinical causes on the recurrences of atrial fibrillation (AF) of patients with acute myocardial infarction(AMI) and paroxysmal atrial fibrillation (AF). Methods: 120 cases of patients with AMI and AF are divided, on whether or not recurrence of AF happened in the one-year follow-up, into two groups: the recurrence group and the normal sinus rhythm (NSR) group. Such data as general information, medical history and treatment of patients of the two groups are compared. At the end of the one-year follow-up, examinations of the patients are conducted on C-reactive protein (CRP), low-density lipoprotein (LDL), left atrial diameter (LAD) and left ventricular ejection fraction (LVEF), and their cardiac function are examined and classified. Results: The averaged age of recurrence group were apparently higher than the NSR group (P<0.01). There were more cases with high blood pressure, anterior myocardial infarction (P<0.01or P<0.05) and lower cardiac function (P<0.01), reveal a lower LVEF (P<0.01) and a larger LAD (P<0.01). On the other hand, the NSR group have lower CRP and LDL (P<0.01) level. Observations on the different treatments showed that patients with successful intravenous thrombolysis and those with treatment of statins have significantly few cases of AF recurrence compared with patients without the application of intravenous thrombolysis and failure to reperfusion. Conclusion: Precipitating factors for the recurrence of AF include senior age, high blood pressure, anterior wall infarction, left atrial enlargement and deterioration of cardiac function. Therefore, early revascularization and treatment with statins are effective measures against the recurrence of AF.

Key words: Acute myocardia infarction (AMI), Atrial fibrillation, Statins, C-reactive protein (CRP)