{
  "abstract": "Background Apical hypertrophic cardiomyopathy (HCM) is a rare variant of HCM, often considered to have a benign prognosis. This study aimed to compare the clinical characteristics and genetic predisposition of apical HCM with non-apical HCM.Methods We included 195 patients with HCM who underwent next-generation sequencing at two tertiary centres in South Korea (2017–2024). The primary outcome was a composite of lethal arrhythmic events (LAE), including death, ventricular arrhythmia, implantable cardioverter defibrillator (ICD) implantation and appropriate ICD shock. Secondary outcomes included major adverse cardiovascular events (MACE), such as new-onset atrial fibrillation, ischaemic stroke, heart failure hospitalisation, septal reduction therapy or heart transplant.Results Of the 195 patients, 67 (34.4%) had apical HCM. Patients with apical HCM were older at diagnosis and had lower maximal left ventricular wall thickness compared with non-apical HCM. Disease-causing variants were less frequent in apical HCM (20.9% vs 46.9%, p<0.001). MYBPC3 and MYH7 variants were less common in apical HCM (50.0%) than in non-apical HCM (75.0%). MACE occurred less frequently in apical HCM (HR 0.38, 95% CI 0.19 to 0.75), but no difference was observed in LAE (HR 0.62, 95% CI 0.36 to 1.08). The presence of disease-causing variants was independently associated with LAE (adjusted HR 2.50, 95% CI 1.44 to 4.35).Conclusions Although apical HCM is associated with less hypertrophy and lower genetic yield, it is not entirely benign. The presence of disease-causing variants is an important predictor of arrhythmic risk, underscoring the value of genetic testing in all HCM patients, regardless of phenotype.",
  "authors": [
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Joo Hee Jeong"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Yeouido St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea"
      ],
      "name": "Hwajung Kim"
    },
    {
      "affiliations": [
        "Department of Radiology, Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Sung Ho Hwang"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Chang-Ok Seo"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Yeji Kim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Hyoung Seok Lee"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Yun Gi Kim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Jaemin Shim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Young-Hoon Kim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "So Ree Kim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Dong-Hyuk Cho"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Mi-Na Kim"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Seong-Mi Park"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea"
      ],
      "name": "Young Choi"
    },
    {
      "affiliations": [
        "Division of Cardiology, Department of Internal Medicine, Korea University College of Medicine and Korea University Anam Hospital, Seoul, Republic of Korea"
      ],
      "name": "Jong-Il Choi"
    }
  ],
  "title": "Genotype and arrhythmic risk in patients with apical hypertrophic cardiomyopathy",
  "uid": "508a271e-6b00-59b2-a8c7-731e6e7f358d"
}