Myxoma is the most common benign heart tumor. Predominant in the left atrium, it is generally a papillary mass with an irregular friable surface, less often ovoid and smooth. They can also be located, in descending order of frequency, in the posterior atrial wall, the anterior atrial wall and the atrial appendage ⁵. This poses differential diagnostic problems with intracardiac thrombus following atrial fibrillation or myocardial infarction. LA thrombus is usually attached to the LA appendage or, the posterior LA wall by a broad base, usually immobile and is not associated with systemic constitutional symptoms [5]. In our patient, the myxoma was round with regular contours and an implantation base at the roof of the left atrium, which was unusual.

From a hemodynamic point of view, its volume and its mobility during the phases of the cardiac cycle can cause pulmonary congestion: either by obstruction of the admission chamber during diastole [6], or by limiting the emptying or filling of the LA [5,8]. This explains the acute heart failure that our patient presented when doing TEE.

LA myxoma associated with mitral regurgitation remains rare. It is responsible either by preventing the coaptation of the mitral leaflets, or by a "Wrecking ball" effect explaining the rupture of chordae tendineae [5,7,9]. In our patient, we suspected a cord rupture, but without real proof on imaging. The surgeon was able to confirm the rupture of one of the cords of the posterior mitral leaflet intraoperatively. The mechanism therefore remains mysterious:  a rupture by acute mitral regurgitation was ruled out in the absence of coronary embolization, and chest pain; and the myxoma did not prolapse through the mitral orifice, thus causing damage to the cords.

In addition, the associated lesion of the right coronary artery in our patient is caused by an atheromatous disease given the nature of the lesion, the cardiovascular risk factors, the absence of an acute presentation in favor of myxoma embolization and finally the type of the mass. Gerasimos Gavrielatos [10] defines two types of myxomas: « a round type typified by a solid and round shape with a nonmobile surface, and a polypoid type characterized by an asymmetrical and soft shape with a mobile surface» [11]. The latter type is a potential source of systemic embolism occurring in a third of myxomas [5,7].  Kumar et al [5] found that the prevalence of coronary artery disease with myxoma ranges from zero to as high as 20.3-36.6%, depending on age and associated risk factors for atherosclerosis. The incidence of coronary embolization of myxomas was 0.06%. According to Sugimot et al [12], embolization seems to depend on the angle between the aortic blood flow and the coronary artery responsible for the infarction.

The management of our patient was a success. He was in total agreement with the management procedure. Open-heart surgery led to an excellent result. Histological study of the operative specimen confirmed the diagnosis and described cells with an ovoid nucleus and abundant eosinophilic cytoplasm with imprecise boundaries, mixed with mononuclear inflammatory cells organized around the vessels. To date, the outcome was favorable without symptoms of dyspnea, and without recurrence.