Unique Congenital Malformation of the Mitral Valve Associated with Anomalous Coronary Arteries and Stroke
A 55-year-old male, smoker and previously healthy, presented to our emergency department for abrupt onset of difficulty reading and right sided weakness, signs and symptoms suggestive of a new onset stroke. Stat computed tomography (CT) and computed tomography angiogram (CTA) of the brain revealed no abnormality. Magnetic resonance imaging of the brain showed acute infarction of the left posterior insular cortex and left parietal subcortical area. The patient was started on aspirin, atorvastatin and clopidogrel. He underwent a routine transthoracic echocardiogram (TTE) as to rule out any possible cardiac source of embolism. TTE revealed an abnormally thickened anterior mitral leaflet associated with mild eccentric mitral regurgitation (MR). Transesophageal echocardiogram (TEE) was performed for further assessment. TEE revealed some form of redundant tissue along the anterior mitral leaflet and the base of the anterior leaflet in the left ventricular outflow tract (LVOT). It is thin and supple, the appearance was neither consistent with a fibroelastoma, nor a tumor, an abscess, a true aneurysm of the sinus of Valsalva nor perimembranous septum. The anterior mitral leaflet is itself thickened and prolapses, which might represent myxomatous disease. A mild eccentric posteriorly directed MR jet was noted, likely originating from the mild prolapse of the anterior leaflet. At the very distal end of the anterior leaflet, there is an echo bright, independently mobile soft tissue entity, 2-3 mm in size. The left circumflex coronary artery (LCX) appears to have both an anomalous origin (very low in the left sinus of Valsalva immediately above the annulus, in closer association to the mitral valve than usual). The ostium of the right coronary artery appears larger than the left coronary artery (, , and , , , and ). Based on these findings, an electrocardiogram-gated cardiac CT scan was suggested. Coronary CTA revealed; anomalous LCX originating from the proximal right coronary artery off the right sinus of Valsalva with a retro-aortic benign course. The mitral valve was described as; thickened anterior mitral valve leaflet with a band like attachment to the membranous inter-ventricular septum, the portion of the band closer to the anterior leaflet forms a thin curvilinear band ( and ). This abnormal appearance could represent a congenital anomaly, myxomatous changes are still probable although may not explain the atypical attachment site. The patient had no fever, blood cultures were negative and all other laboratory investigations were within normal limits. The patient remained in hospital for one week and discharged later with a minor neurological deficit. In the absence of obstruction of the LVOT, the patient is being followed up without surgical intervention.