Double-Orifice Mitral Valve Associated with Noncompaction of Left Ventricular Myocardium

Abstract

Double-orifice mitral valve (DOMV) is a rare anomaly commonly associated with other congenital heart diseases. We present two patients with DOMV and noncompaction of the left ventricular myocardium (NLVM). Case 1 was a 5-year-old male diagnosed with dilated cardiomyopathy. His echocardiogram showed thin myocardium with dilatation at the basal of the left ventricle, thick noncompacted myocardium around the apex of the left ventricle, and DOMV (complete bridge type) with mild mitral regurgitation. Case 2 was an 11-year-old male diagnosed with complete atrioventricular block. His echocardiogram showed thick noncompacted myocardium with mild hypokinesis from the posterior to lateral wall and DOMV (complete bridge type) with mild mitral regurgitation. DOMV is commonly associated with congenital anomaly and always has an abnormal subvalvar apparatus. The mitral valve and its apparatus embryologically originate from the endomyocardium, which is thought to be the origin of noncompacted myocardium. We speculate that patients with DOMV may have NLVM.

Complete atrioventricular block and reversible systolic dysfunction in left ventricular hypertrabeculation/non-compaction with metabolic myopathy

“…The coexistence of mitral valve abnormalities and atrioventricular block in left ventricular hypertrabeculation/non-compaction has been described previously. 4,11 Most probably, these abnormalities were congenital since both of these previously described cases are children or adolescents, like our patient. Systolic dysfunction in our patient may be due to the insufficiently dosed pharmacotherapy, inadequate rhythm control and coexisting myopathy with cardiac involvement.…”

“…1,2 Occasionally, complete atrioventricular block, either congenital or acquired, may be associated with left ventricular hypertrabeculation/non-compaction (Table 1). [2][3][4][5][6][7][8][9][10][11][12][13][14] Case report…”

Biventricular myocardial noncompaction presenting with complete atrioventricular block

“…The NCVM cases with concomitant double orifice mitral valve [3], atrial fibrillation [4], and atrial septal aneurysm and mitral valve cleft [5] presenting with complete atrioventricular block were reported in the literature. With this report, we have presented a biventricular NCVM case with concomitant valvular insufficiency, in all four heart valves, complicated with complete atrioventricular block.…”

Double orifice mitral valve combined with left ventricular noncompaction in a child with Sotos syndrome

“…Although the combination of DOMV and LVNC could be a coincidence considering the rarity of the diseases, it is intriguing that both abnormalities have been explained by developmental arrest of the endomyocardium. In fact, several cases with this combination have been reported in the literature [7][8][9][10].…”