Multimodality Imaging of a Dissecting Intramyocardial Hematoma Extending into the Left Atrial Wall Following Myocardial Infarction
Five days after the onset of substernal chest pain, a 60-year-old man with a history of hypertension, smoking (60 pack-years), severe bullous emphysema, and epilepsy presented with acutely worsening chest pain. Pharmacological management for non–ST-segment elevation myocardial infarction was initiated based on 12-lead ECG findings of subtle anterolateral ST segment changes (V2–V5) and a troponin I level of 6.36 ng/mL (normal <0.04 ng/mL).
Invasive angiography demonstrated a distal occlusion of a right posterolateral branch and a nonocclusive stenosis in the distal circumflex artery (Figure 1A and ⇓B). Cineangiography showed two small craters of contrast protruding outside the contrast-filled left ventricular contour within a dyskinetic basal inferior wall (Figure 1C and ⇓D and online-only Data Supplement Movie I). Because the occlusion was distal, percutaneous coronary intervention was not performed. Transthoracic echocardiography showed heterogeneous echogenicity within a 28-mm-thick, dyskinetic, inferior left ventricular wall (online-only Data Supplement Movie II) and a mass protruding into the left atrium (Figure 2). This unusual mass was suspicious for an intramyocardial hematoma based on the clinical setting and its location within myocardium subtended by the occluded artery. Left ventricular ejection fraction was estimated visually to be 45%. There were wall motion abnormalities in the basal and midanterolateral, inferolateral, and inferior walls extending into the apical inferior wall. In retrospect, the anterolateral ST changes likely represented a combination of inferior and inferolateral infarct and ischemia. All antiplatelet and …