探讨以心脏扩大为首发表现的急性心肌梗死的临床特点及误诊原因。

回顾性分析2020年7月30日济宁医学院附属医院心内科监护室收治的1例急性心肌梗死患者的临床资料，并进行文献复习。

患者41岁，男性，入院前10 d受凉后出现咳嗽，咳少量白痰，胸闷逐渐加重，活动耐力降低。心脏超声检查示左心、右房增大，左室整体功能减低，左室射血分数(LVEF)43%，诊断为扩张型心肌病，治疗3 d后患者仍感胸闷不适。入院后复查心脏超声，LVEF降至22%；行心脏磁共振成像检查符合急性心肌梗死磁共振表现；行冠状动脉造影检查发现前降支发出第一对角支后狭窄95%，第一对角支开口近段狭窄80%，于前降支狭窄处植入药物洗脱支架一枚。随访患者心脏超声，心功能恢复良好，出院后8个月LVEF升至56%。

心脏磁共振成像检查对不典型急性心肌梗死诊断具有重要意义；血运重建及充分药物治疗可以逆转急性心肌梗死心室重构。

To explore the clinical characteristics and misdiagnosis reasons of acute myocardial infarction with cardiac enlargement as the first manifestation.

The clinical data of a patient with acute myocardial infarction admitted to the Cardiac Care Unit of Affiliated Hospital of Jining Medical University on July 30, 2020 was retrospectively analyzed, and relative literatures were reviewed.

The 41-year-old patient developed a cough and a small amount of white phlegm for 10 days before admitted to the hospital, with gradually increasing chest tightness, and decreasing activity endurance. Echocardiography showed left ventricle and right atrium was enlarged, left ventricle contraction was markedly impaired, and left ventricular ejection fraction (LVEF) was 43%. He was diagnosed with dilated cardiomyopathy, and still felt chest tightness and discomfort after 3 days of treatment. After admission, echocardiography showed that LVEF decreased to 22% and the manifestations of cardiac MRI were consistent with the changes of acute myocardial infarction. Coronary angiography showed that the stenosis in LAD after D1 was 95%, the proximal part of D1 stenosis was 80%, and a drug-eluting stent was implanted at the stenosis of LAD. Following discharge, follow-up echocardiography revealed good heart function recovery, with LVEF increasing to 56% 8 months later.

Cardiac MRI is of great significance in the diagnosis of atypical acute myocardial infarction. Revascularization and adequate medical treatment can reverse ventricular remodeling in acute myocardial infarction.