ST Segment Elevation Myocardial Infarction and Severe Coronary Aneurysms in Neurofibromatosis Type 1
Meghana Patil, MD, Temple University Hospital – Main Campus, Philadelphia, PA
Meghana Patil, MD1, Oby Ibe, MD, MPH1, Rohit Maruthi, MD1, Vladimir Lakhter, D.O.2, Marinos Charalambous, M.D.3, Aditi Kalla, MD1 and Karan Kapoor, MD1, (1)Temple University Hospital – Main Campus, Philadelphia, PA, (2)Massachusetts General Hospital, Boston, MA, (3)Northwell Health North Shore University Hospital, New York, NY
Title
ST Segment Elevation Myocardial Infarction and Severe Coronary Aneurysms in Neurofibromatosis Type 1
Introduction
This case describes an approach to overcome the unique challenges of percutaneous management of ST elevation myocardial infarction (STEMI) in patients with coronary aneurysms associated with Neurofibromatosis type 1 (NF1). Crucial steps included use of intravascular ultrasound (IVUS), aggressive atherosclerotic risk factor modification, and oral anticoagulant therapy for successful long-term stent patency.
Clinical Case
This patient is a 62-year-old male with a history of NF1, hypertension, hyperlipidemia and tobacco use who presented to the emergency department with acute substernal chest pressure. Vitals and cardiopulmonary exams were normal. Skin exam showed numerous neurofibromas. ECG showed ST elevations in V1-V3 meeting STEMI criteria, and thus he was emergently taken to the catheterization lab. Coronary angiography demonstrated aneurysm disease and 100% occlusion of the mid left anterior descending artery (LAD), as well as moderate diffuse disease and aneurysmal disease throughout the left circumflex and right coronary arteries. In the mid-LAD, thrombectomy was performed followed by balloon angioplasty. Initial IVUS showed atherosclerosis and acute plaque rupture in a large aneurysmal vessel segment. A drug eluting stent was successfully placed (4.0X23mm XIENCE, post-dilated to 5.0mm). Repeat IVUS showed a well-opposed and fully expanded stent. The lesion had TIMI flow 3 with 0% stenosis post-procedurally. He was discharged on dual antiplatelet therapy for one year, with subsequent transition to single antiplatelet and anticoagulation. Risk factors such as hyperlipidemia were aggressively treated, including use of PCSK9 inhibitor. Repeat coronary angiography performed two years later in the setting of abnormal stress test showed that the stent remained widely patent with no in-stent restenosis.
Discussion
Coronary aneurysms seen in NF1 are a small subset of possible vascular abnormalities seen with this disease, including aneurysms of aorta, mesenteric or cerebral arteries, as well as renal artery stenosis. STEMI in NF1 patients is a rare presentation and has previously been associated with unsuccessful percutaneous outcomes, pushing clinicians towards pursuing a surgical approach or medical management. Our case is the first reported IVUS guided successful percutaneous treatment of STEMI in NF1. IVUS was critical not only to evaluate extent of disease (not well visualized by angiography alone), but also to determine appropriate stent sizing/placement, evaluate stent opposition and need for post-dilation. Prior literature also suggests stenoses may be concealed within aneurysms, visible only by IVUS. If no clear stenosis is seen on initial angiography, another suggested technique is intracoronary provocation, as NF1 can predispose patients to severe coronary spasm. Other considerations in NF1 includes aggressive cardiovascular risk factor modification (as atherosclerosis accounts for 50% of coronary aneurysms), full body vascular imaging to identify additional aneurysmal disease, and possible long-term oral anticoagulation. Data has shown that benefits of anticoagulation therapy in patients with coronary aneurysms may outweigh risks in terms of long-term cardiovascular outcomes, including recurrence of thrombus formation and myocardial infarction. For our patient, a combination of these techniques have resulted in successful percutaneous treatment of this patient’s prior myocardial infarction without significant disease progression over a two year follow up period.