Impact of sex and age on culprit plaque type of acute coronary syndrome in Japanese patients from TACTICS registry

Abstract Background In acute coronary syndrome (ACS), plaque rupture (PR) is the most frequent etiology followed by plaque erosion (PE) while calcified nodule (CN) is the least etiology. These three are known as major etiologies of ACS. Traditionally, it has been believed that sex and age have impact on etiology of ACS. For example, plaque erosion was thought to often occur in young female while calcified nodule often occur in elderly patients. However, impact of sex and age have not been well described. Methods This is a sub-study from TACTICS registry which consist of 702 Japanese ACS patients who underwent primary percutaneous coronary intervention under optical coherence tomography (OCT) from multicenter. Based on the OCT findings, patients were divided into PR, PE, CN and others. These data were stratified by sex and ages (<50, 50s, 60s, 70s, 80 or over). In this sub-study, we mainly focused on 3 major etiologies of ACS (PR, PE, CN) and compared incidence and clinical characteristics based on sex and ages. Results Distribution of culprit plaque type in ACS patients are shown in figure 1A (male) and 1B (female). PR remained top etiology of ACS in any sex and any age category. However, trend of PE was different between male and female. In male, as patients get younger, incidence of PE increased. In male patients under 50, incidence of PE was almost similar as PR. On the other hand, in female, incidence of PE was greatest in 70s followed by 80 or over. Surprisingly, young female showed the least incidence of PE. CN was the least etiology of three but increased especially from 80. Clinical characteristics are shown in table 1A (male) and 1B (female). In male, most of the baseline characteristics differ between different ages while in female, most of the baseline characteristic did not differ between different ages. Conclusion In our data, PE was more distinct in younger male ACS patients while PE was not that distinct in younger female ACS patients. The impact of sex and age on culprit plaque type of ACS might be variable depending on population.