{
  "abstract": "Objective To evaluate the potential mediating role of left ventricular ejection fraction (LVEF) in the relationship between replacement fibrosis (assessed by late gadolinium enhancement (LGE)) and sudden cardiac death (SCD) post-myocardial infarction (MI) and also to assess this mediation effect in subgroups based on LVEF ≤ 35% and > 35% according to implantable cardioverter-defibrillator (ICD) selection criterion.Methods A retrospective analysis was conducted on 917 post-MI patients (mean age: 56.3±11.0 years, 88.8% male) who underwent cardiac MR from January 2017 to August 2021. The endpoint for SCDs included SCD, aborted SCD and appropriate ICD discharges. The association of LGE with LVEF was quantified using linear regression models. The associations of LGE and LVEF with SCDs were evaluated using competing risk models. Mediation analysis was then used to decompose the total effect of LGE on SCDs into direct and indirect (mediated through LVEF) effects using accelerated failure time models.Results Over a median follow-up of 63.3 (IQR, 43.6 to 76.6) months, 65 patients (7.1%) experienced SCDs. In all patients, LGE was significantly associated with lower LVEF (β=-0.35, p<0.001). Both LGE and LVEF independently predicted SCDs (subdistribution hazard ratio (sHR)=1.06, p<0.001; sHR=0.95, p=0.03, respectively). Mediation analysis showed that LVEF accounted for 19.7% of the total effect of LGE on SCDs (p<0.001). This mediation effect was 40.4% in patients with LVEF > 35% (p = 0.02), while no mediation was observed in patients with LVEF ≤ 35% (p = 0.08).Conclusion LVEF partially mediated the effect of LGE on the SCD, accounting for less than one-fifth of the total effect. LVEF alone inadequately captured the whole SCD risk, irrespective of whether LVEF is greater than 35% or 35% or less.",
  "authors": [
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Pengyu Zhou"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Kaisaierjiang Aisikaier"
    },
    {
      "affiliations": [
        "Department of Radiology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Zhixiang Dong"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Xuan Ma"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Yun Tang"
    },
    {
      "affiliations": [
        "Department of Nuclear Medicine, Peking University People's Hospital, Beijing, China"
      ],
      "name": "Zhuxin Wei"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Xi Jia"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Xingrui Chen"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Yujie Liu"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Wenqing Xu"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Fen Sa"
    },
    {
      "affiliations": [
        "Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China"
      ],
      "name": "Shu-Juan Yang"
    },
    {
      "affiliations": [
        "Department of Radiology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Jiaxin Wang"
    },
    {
      "affiliations": [
        "Department of Radiology, West China School of Medicine, Sichuan University, Sichuan University affiliated Chengdu Second People's Hospital, Chengdu, China"
      ],
      "name": "Fengnian Zhao"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Minjie Lu"
    },
    {
      "affiliations": [
        "Department of Radiology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China"
      ],
      "name": "Xinxiang Zhao"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Xiuyu Chen"
    },
    {
      "affiliations": [
        "Department of Radiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China"
      ],
      "name": "Shihua Zhao"
    }
  ],
  "title": "Replacement fibrosis, left ventricular ejection fraction and sudden cardiac death in patients after myocardial infarction: a mediation analysis",
  "uid": "bb355dea-3e8f-527b-a104-63ed556d52ef"
}