Methods:
An electrocardiogram (ECG) demonstrated ST-segment depressions in leads V5-6 and T-wave inversions in leads II and III. Initial troponin levels were elevated at 684 pg/mL, and he was also noted to have acute kidney injury. A computed tomography angiogram ruled out aortic dissection but revealed a 2.3 cm filling defect in the left ventricle, consistent with a thrombus (Figure 1). After administration of morphine and diazepam, the patient’s chest pain improved. He was started on a heparin infusion, aspirin, clopidogrel, and atorvastatin.
Transthoracic echocardiography revealed a significantly reduced left ventricular ejection fraction of 10-15%, grade III diastolic dysfunction, and the presence of a left ventricular apical thrombus. A repeat ECG showed no new ST elevations, but persistent ST depressions in the high lateral leads and T-wave inversions in the inferior leads were noted. The repeat troponin level increased to 10,970 pg/mL. Given these findings, the decision was made to transfer the patient to the cardiac catheterization laboratory for further evaluation and admit him to the coronary care unit (CCU) for close monitoring, with a diagnosis of non-ST elevation myocardial infarction (NSTEMI).
Coronary angiography revealed a normal right coronary artery (RCA) proximally and mid-segment, but extensive clot burden and total occlusion distally (Figure 2). The left main artery, left anterior descending (LAD) artery, and left circumflex artery were free of significant disease. A left ventriculogram showed no visible ventricular thrombus, but left ventricular end-diastolic pressure (LVEDP) was elevated at 33 mmHg.
A decision was made to proceed with mechanical thrombectomy. Heparin was administered to maintain an activated clotting time of 300-350 seconds, and the RCA was engaged with a Judkins Right 4 (JR4) 6-French guide catheter. A balanced middleweight (BMW) coronary guidewire was used to cross the thrombus and was placed in the distal posterior descending artery. Multiple passes of mechanical thrombectomy were performed using the Penumbra CAT RX device. The wire was then repositioned into the right posterolateral ventricular branch, and another thrombectomy run was completed.