Familial Mitral Arcade, Tricuspid Dysplasia, Left Ventricular Noncompaction and Short-Chain Acyl-CoA Reductase Deficiency.

Mitral arcade is a rare entity that is mostly reported in pediatric patients. We present the first 2 adult cases of mitral arcade in combination with tricuspid dysplasia, left ventricular noncompaction, and short-chain acyl-CoA deficiency in 2 brothers. We examined clinical and echocardiographic data on 2 brothers with a combination of short-chain acyl-CoA deficiency, mitral arcade, tricuspid dysplasia, and left ventricular noncompaction (LVNC), highlighting their clinical course and outcomes. Two-dimensional and 3-dimensional transthoracic echocardiography revealed direct attachment of the papillary muscles to the mitral leaflets, namely mitral arcade, as well as mild mitral regurgitation along with LVNC and tricuspid dysplasia. Over the past 7 years, both brothers have remained asymptomatic with excellent exercise capacity (13 and 10 metabolic equivalents (METS), respectively). Mitral and tricuspid regurgitation remain mild with unchanged left ventricular function (ejection fraction: 65% and 59%). In conclusion, we highlight 2 cases with a constellation of pathology including short-chain acyl-CoA deficiency, mitral arcade, tricuspid dysplasia, and LVNC, which has never been described before.