CONGRESS ABSTRACT

Background: The differential diagnosis between STEMI and STEMI mimics is crucial for an accurate diagnosis, enabling the definition of a therapeutic pathway with a significant impact on the patient's prognosis. We present a clinical case of ST-segment elevation during acute abdominal pathology that could have led to an incorrect diagnosis and inappropriate therapeutic choices. Case Presentation: An 89-year-old woman was brought by emergency services to the emergency department with symptoms consistent with acute abdomen. The cardiologist was alerted because, during transport, the patient exhibited a reduced heart rate with atrial tachycardia with variable conduction and ST-segment changes suggestive of inferior STEMI (Fig.1). The patient, who was partially conscious, reported no chest pain but complained only of abdominal pain, which was exacerbated by palpation of all abdominal quadrants. Echocardiography showed severe concentric left ventricular hypertrophy with preserved wall thickness across all segments but an abnormal motion of the inferior wall. An anechoic layer was detected in the upper abdominal quadrants, prompting an abdominal CT scan. The scan revealed intestinal obstruction causing gastric distension and diaphragmatic compression (Fig.2). A nasogastric tube was placed, and approximately three liters of coffee-ground fluid were aspirated, resulting in symptom relief, normalization of the ST-segment changes, and increased conduction through the atrioventricular node (Fig.3). Discussion: Literature describes several cases where increased intra-abdominal pressure and the compression of the hemidiaphragm on the epicardial vessels and the myocardium induce an alteration of the ST segment. In this clinical case, this alteration was accompanied by a rhythm disturbance also consistent with an inferior STEMI diagnosis. These findings could raise suspicion of vagal nerve involvement in the electrocardiographic changes. The reduction of intra-abdominal pressure and the resolution of painful symptoms led not only to the resolution of the STEMI mimic scenario but also to an increase in atrioventricular node conduction. However, it is extremely important to evaluate the patient by integrating the clinical and instrumental findings, which in our case allowed for an accurate diagnosis, avoiding coronary angiography and antiplatelet/anticoagulant therapy, thereby preventing interference with the surgical procedure the patient required.