Higher Recurrence Rate of Acute Coronary Syndrome in Patients with Multiple-Time Myocardial Infarction.

The recurrence rate of acute coronary syndrome (ACS) in patients after first-time myocardial infarction (MI) is over ten times higher than in the general population. However, it is unclear whether patients with multiple-time MI have an even higher recurrence rate of MI. This study aimed to compare the recurrence rate in patients with multiple-time MI with the rate in patients after first-time MI. We retrospectively studied 794 consecutive MI patients who were discharged. Recurrent ACS was investigated in patients with previous MI (n = 46) and without previous MI (n = 748). During the follow-up periods (mean ± SD: 757 ± 733 days), recurrent ACS occurred in 47 cases without previous MI and in 7 cases with previous MI. Kaplan-Meier analysis revealed that the risk of recurrent ACS was significantly higher in patients with previous MI than in patients without previous MI. ACS recurrence rates one year from the onset were 4.2% in patients without previous MI and 11.9% in patients with previous MI. Landmark analysis revealed that the higher recurrence rate in patients with previous MI was as high as 14.1% from 1 year after the onset to 2 years. In conclusion, the risk of recurrent ACS may be significantly higher in patients with multiple-time MI than in patients after first-time MI.