SPONTANEOUS CORONARY ARTERY DISSECTION RESULTING IN MITRAL VALVE REPLACEMENT

Abstract

TOPIC: Cardiovascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Spontaneous coronary artery dissection (SCAD) is a rare condition accounting for only 0.1%–4% of acute coronary syndromes and 0.4% of sudden cardiac deaths. It predominantly affects young women with few or no traditional cardiovascular risk factors and is commonly associated with fibromuscular dysplasia (FMD), connective tissue disorders, and recreational drug use. Herein, we report a rare case of Type 2A SCAD in a male patient further complicated by the development of severe mitral valve regurgitation requiring mitral valve replacement (MVR). CASE PRESENTATION: A 47-year-old male with a history of hypertension, hyperlipidemia, and renal artery stenosis presented with complaints of fatigue, dyspnea, and chest pain. The initial EKG showed nonspecific ST changes, and troponin was elevated to 10 ng/dL (normal: <0.49 ng/dL). An urgent cardiac catheterization demonstrated non-obstructive coronary artery disease. Computed tomography (CT) of the chest ruled out a pulmonary embolism. The patient's troponin following cardiac catheterization continued to trend up with a peak of 23 ng/dL, at which point a formal transthoracic echocardiogram (TTE) was found to be normal. He had one recurrence of chest pain which correlated with another troponin spike and was found to have a decreased ejection fraction on emergent repeat TTE (EF: 45-50%). A third TTE was performed due to a new systolic murmur which showed a further decrease in EF (40-45%) and new mild MR. At this point, our leading differential diagnosis was myocarditis. Cardiac MRI showed an area of transmural late gadolinium enhancement involving the mid left ventricular inferolateral wall with islands of sparing which raised suspicion for a myocardial infarction (Figure 1), however, on further retrospective review of the cardiac angiogram, the findings (in correlation with the MRI) were consistent with narrowing in the obtuse marginal (OM) 1, a branch of the left circumflex artery, concerning for SCAD type 2. The patient was discharged home in stable condition with the diagnosis of SCAD of the OM-1 branch. Unfortunately, the patient returned with worsening dyspnea and was found to have severe MR which had progressed rapidly from the prior TTE. Given the circumflex distribution, and rapidly progressive MR, the patient was emergently referred for cardiothoracic surgery evaluation and ultimately underwent MVR. DISCUSSION: Any epicardial artery can be involved in SCAD, the left anterior descending artery is the most commonly affected. In this case, the involvement of the OM-1 resulted in impaired perfusion of the lateral wall and the anterolateral papillary muscle, subsequently leading to papillary rupture and MR. CONCLUSIONS: Even though this condition most commonly affects the female population, and is further primarily associated with connective tissue disorders, our work up revealed no such underlying conditions. REFERENCE #1: https://www.ahajournals.org/doi/10.1161/CIR.0000000000000564 DISCLOSURES: No relevant relationships by Nicole Anthony, source=Web Response no disclosure on file for Erdal Cavusoglu; no disclosure on file for Muhammad Dogar; No relevant relationships by Dilpat Kumar, source=Web Response No relevant relationships by Kamal Preet Singh, source=Web Response