Janelle Buysse, DO & Umang Gupta, MD
Double-orifice left atrioventricular valve (DOLAVV) or double-outlet mitral valve (DOMV) is a rare congenital defect that can be seen with other congenital heart defects, most commonly Atrioventricular Septal Defects (AVSD), and can also be found in isolation. The hemodynamic significance of DOMV can vary from a normally functioning valve to a cause of significant stenosis or regurgitation. Regardless of hemodynamic significance, DOMV can pose a challenge to surgeons and complicate surgical repairs. Therefore, the recognition and description of DOMV prior to surgical repair is important in surgical planning and prognostication. We present a case of DOLAVV where a non-sedated, three-dimensional (3D) transthoracic echocardiogram (TTE) was effectively utilized to diagnose the condition in a patient with AVSD when 2D and Doppler imaging could not clarify the diagnosis.
FIGURE 1 TTE left AV valve with double orifice and cleft reconstructed from full volume 3D data set acquisition seen from ventricular side. DOMV = Double orifice mitral valve
A 12-month-old male presented to a local emergency department for evaluation of fever and respiratory distress. He was found to be influenza A-positive and was transferred to a pediatric unit in a community hospital for bronchiolitis treatment where a chest X-ray was obtained which showed cardiomegaly. An electrocardiogram (ECG) and transthoracic echocardiogram (TTE) were obtained. ECG showed biatrial enlargement, biventricular hypertrophy, right-axis deviation, and ST segment changes. TTE showed large Atrial Septal Defect (ASD), right-atrium (RA) and left-atrium (LA) dilation, right ventricle (RV) dilation, and concerns for pulmonary hypertension. No concerns for DOLAVV were raised. He was transferred to our pediatric intensive care unit. On arrival, further history revealed poor weight gain since around six months of age despite taking appropriate volumes of formula for age. Family denied any diaphoresis or fatigue with feeds, but reported noticing his "heart racing" through his chest that was more prominent during illnesses and had seemed to get more noticeable over the few months prior to admission. Physical examination on arrival revealed an active precordium with visible point of maximal impulse and regular rate and rhythm with normal S1 and S2. There was a III/VI systolic ejection murmur appreciated best at the left-upper sternal border. Repeat TTE at our institution revealed intermediate type AVSD with a single annulus and two separate atrioventricular (AV) valves with a large primum ASD and a small-inlet Ventricular Septal Defect (VSD). There was mild-to-moderate right-sided AV valve regurgitation. The Left AV valve appeared to have cleft with left ventricle (LV) to RA shunt with no significant left AV valve insufficiency. There was some septal/left ventricular outflow tract (LVOT) attachment from left AV valve without any LVOT obstruction. There was dilation of RA, RV and main and branch pulmonary arteries. ECG showed sinus tachycardia with left axis deviation, right-atrial enlargement and biventricular hypertrophy. He was admitted for four days for influenza A bronchiolitis- related respiratory failure. He was started on scheduled furosemide and discharged home with close outpatient cardiology follow-up with anticipated surgical repair when he recovered from his viral illness.
To read the full article, please go to the February 2021 Issue of CCT.