Department of Forensic Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita, 879-5593, Japan.
Department of Diagnostic Pathology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita, 879-5593, Japan.
Cardiovasc Diabetol. 2024 Oct 24;23(1):378. doi: 10.1186/s12933-024-02456-z.
We aimed to clarify the existence and pathological features of obesity cardiomyopathy (OCM) in Japan using our series of autopsy cases.
In this retrospective autopsy study, OCM was defined as cardiac hypertrophy (≥ 400 g in men, ≥ 320 g in women) of unknown aetiology in individuals with obesity (body mass index [BMI] ≥ 25 kg/m according to the Japanese definition of obesity). We compared cases of OCM with those with obesity without cardiac hypertrophy (OB) and normal weight without cardiac hypertrophy (normal control). Macroscopically, heart weight and cardiac parameters, including epicardial adipose tissue, were measured. Fibrosis, cardiomyocyte diameter, and adipose tissue infiltration were analysed microscopically.
Of the 294 cases, we identified 19 cases of OCM (6.5%) and compared them with the OB and normal control groups. Patients with OCM were slightly younger than non-OCM patients (p = 0.081). The median heart weight was significantly heavier in OCM cases than in OB cases (435 g, interquartile range [IQR] 408-515 g vs. 360 g, IQR 341-385 g). Macroscopically, OCM hearts had a "globoid" appearance with a thickened right ventricular outflow tract. Some OCM cases showed focal interstitial fibrosis in the left ventricle. Approximately half the OCM cases were diagnosed with sudden cardiac death (SCD), with significant differences.
The prevalence of OCM may be higher than expected in Japan, and this may be a specific pathological finding. Given that approximately half the cases of OCM were due to SCD, OCM may cause SCD, emphasizing the need to recognise and diagnose OCM.
本研究旨在通过系列尸检病例阐明日本肥胖性心肌病（OCM）的存在及病理特征。
本回顾性尸检研究中，OCM 定义为肥胖个体（日本肥胖定义为 BMI≥25kg/m²，男性心脏重量≥400g，女性≥320g）中病因不明的心肌肥厚（≥400g，男性；≥320g，女性）。我们将 OCM 病例与肥胖但无心肌肥厚（OB）病例和体重正常但无心肌肥厚（正常对照）病例进行比较。肉眼观察测量心脏重量和心外膜脂肪组织等心脏参数。显微镜下分析纤维化、心肌细胞直径和脂肪组织浸润情况。
在 294 例患者中，我们确定了 19 例 OCM（6.5%）病例，并与 OB 和正常对照组进行了比较。OCM 患者的年龄略小于非 OCM 患者（p=0.081）。OCM 病例的心脏重量中位数明显高于 OB 病例（435g，四分位距[IQR] 408-515g 比 360g，IQR 341-385g）。肉眼观察 OCM 心脏呈“球形”，右心室流出道增厚。部分 OCM 病例左心室可见局灶性间质纤维化。约一半的 OCM 病例诊断为心源性猝死（SCD），差异有统计学意义。
OCM 在日本的患病率可能高于预期，这可能是一种特定的病理发现。鉴于约一半的 OCM 病例是由于 SCD，OCM 可能导致 SCD，这强调了识别和诊断 OCM 的必要性。
