Images and Case Reports in Interventional Cardiology Left Main Pseudoaneurysm After Postpartum Coronary Dissection

The patient is a 34-year-old woman, para 3, gravida 3, with dyslipidemia and former tobacco use, who 1-week postpartum experienced an acute myocardial infarction. Initial angiography revealed a left main (LM) artery dissection with probable subintimal hematoma extending into the proximal left anterior descending (LAD) and left circumflex (LCX) coronary arteries (Figure 1A). Left ventriculography revealed anterior and apical akinesis with an ejection fraction of 30%. Because definitive therapy with percutaneous revascularization carries the risk of dissection extension and occlusion and because there was minimal luminal encroachment and TIMI (thombolysis in myocardial infarction) flow grade 3, we elected for medical therapy, including aspirin, and further observation. Also controversially, we elected not to anticoagulate because of the theoretical potential to maintain false lumen patency. Because of the high-risk nature of the problem and the unpredictable natural history, surveillance angiography 1 week after myocardial infarction was performed and revealed obvious progression of the LM dissection flap into the proximal LAD and LCX arteries, with significant luminal narrowing and TIMI 2 flow in the LAD artery (Figure 1B). Therefore, the patient was scheduled for urgent coronary artery bypass graft surgery, receiving 3 grafts: a left internal mammary artery to the LAD and vein grafts to the diagonal and obtuse marginal (OM) branches. As part of her follow-up, the patient underwent a cardiac CT angiography (CCTA) 1-month after the coronary artery bypass graft surgery, which suggested an occluded diagonal vein graft and the development of an LM pseudoaneurysm (Figure 2A). A repeat CCTA 7 months later suggested enlargement of the pseudoaneurysm (Figure 2B). An elective coronary angiogram was performed to further evaluate the patient’s coronary anatomy. The ejection fraction had improved to 55%. There was a 40% stenosis in the LM with what appeared to be a large pseudoaneurysm (Figure 3A and Movie 1). The LAD, LCX, and right coronary artery had minimal disease. The left internal mammary artery was patent but was small and atretic ( 1.5 mm) with competitive flow. The vein graft to the diagonal branch was chronically occluded. The vein graft to the OM branch was widely patent with good retrograde flow into the LAD. Because of the wide neck of the pseudoaneurysm, which was unlikely to be excluded with conventional percutaneous coronary intervention, we elected to proceed with a covered coronary stent (JOSTENT GRAFTMASTER Coronary Stent Graft System; Abbott Vascular Inc; Murrieta, CA) to the LM artery. Because use of the covered stent would be off label, approval for use was obtained for a Humanitarian Device Exemption through the Internal Review Board. Before the procedure, an intravascular ultrasound was performed to accurately measure the diameter (3.27 mm) and length (13.9 mm) of the LM artery (Figure 4). Primary