Lao Nicole, Laiq Zenab, Courson Jeffrey, Al-Quthami Adeeb
Department of Internal Medicine, Cleveland Clinic Akron General, Akron, 1 Akron General Ave, Akron, OH, USA 44307, USA.
Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Cleveland Clinic Akron General, Akron, 1 Akron General Ave, Akron, OH, USA 44307, USA.
Eur Heart J Case Rep. 2021 Jun 23;5(6):ytab213. doi: 10.1093/ehjcr/ytab213. eCollection 2021 Jun.
Desmosomes are specialized intercellular adhesive junctions of cardiac and epithelial cells that provide intercellular mechanical coupling through glycoproteins, one of which is desmoglein (DSG). DSG-2 mutations are frequently associated with biventricular arrhythmogenic cardiomyopathy (ACM). We report a case of left-dominant ACM in a patient who initially was misclassified as dilated cardiomyopathy (DCM).
A 28-year-old-woman was found to have a moderately reduced left ventricular (LV) systolic function and frequent premature ventricular contractions (PVCs). Targeted genetic testing revealed a heterozygous likely pathogenic variant associated with ACM in exon 15 of the DSG-2 gene (c.3059_3062del; p.Glu1020Alafs*18). Subsequent cardiac magnetic resonance (CMR) imaging showed epicardial and mid-myocardial fatty infiltration involving multiple LV wall segments, multiple areas of mid-myocardial fibrosis/scar, regional dyskinesis involving both ventricles, and an overall reduced left ventricular ejection fraction. The patient's right ventricular (RV) cavity size and overall RV systolic function were normal. Based on the patient's frequent PVCs, family history, fibrofatty myocardial replacement in multiple LV segments, and dyskinetic motion of multiple ventricular wall segments (predominantly affecting the LV), the patient was diagnosed with left-dominant ACM.
Identifying a likely pathogenic mutation associated with ACM in a patient with ventricular arrhythmias and a family history of sudden cardiac death increased the possibility of ACM. Subsequent CMR imaging confirmed the diagnosis of left-dominant ACM by demonstrating regional biventricular dyskinesia and a characteristic pattern of fibrofatty myocardial replacement. Our case highlights the importance of targeted genetic testing and advanced cardiac imaging in distinguishing left-dominant ACM from DCM.
桥粒是心脏和上皮细胞特化的细胞间黏附连接，通过糖蛋白提供细胞间机械耦联，其中一种糖蛋白是桥粒芯糖蛋白（DSG）。DSG-2突变常与双心室致心律失常性心肌病（ACM）相关。我们报告一例左心室优势型ACM患者，该患者最初被误诊为扩张型心肌病（DCM）。
一名28岁女性被发现左心室（LV）收缩功能中度降低且频发室性早搏（PVC）。靶向基因检测显示DSG-2基因第15外显子存在一个与ACM相关的杂合可能致病变异（c.3059_3062del；p.Glu1020Alafs*18）。随后的心脏磁共振（CMR）成像显示心外膜和心肌中层脂肪浸润累及多个左心室壁节段、多个心肌中层纤维化/瘢痕区域、双心室局部运动障碍以及左心室射血分数总体降低。患者右心室（RV）腔大小和右心室整体收缩功能正常。基于患者频发的PVC、家族史、多个左心室节段的纤维脂肪性心肌替代以及多个心室壁节段（主要影响左心室）的运动障碍，该患者被诊断为左心室优势型ACM。
在一名有室性心律失常和心脏性猝死家族史的患者中发现与ACM相关的可能致病突变增加了ACM的可能性。随后的CMR成像通过显示双心室局部运动障碍和纤维脂肪性心肌替代的特征性模式，证实了左心室优势型ACM的诊断。我们的病例强调了靶向基因检测和先进心脏成像在区分左心室优势型ACM与DCM中的重要性。
