Case Report
Informed written consent was taken from the patient for publication. A 2 year male child presented with history of recurrent chest infection and failure to thrive, since 6 months of age. On examination, along with pre cordial bulge, a pansystolic murmur, was heard over left lower sternal border. Echocardiography revealed complete AVCD, moderate tricuspid regurgitation (TR), severe MR and dilation of RA and RV. Since room air saturation was 90% and echo revealed bidirectional flow, cardiac catheterization was done to assess for operability. Baseline Qp / Qs was 2.173 and ratio of pulmonary vascular resistance (PVR) to systemic vascular resistance (SVR) was 0.347. Post oxygen supplementation, the Qp/Qs was 15 and the ratio PVR/SVR dropped to 0.036. Further, ventricular septal defect (VSD) was almost closed; hence patient was labeled as a case of transitional AVCD with severe MR with moderate TR with operable hemodynamics.
Pre-operative on table trans-thoracic echocardiography (TTE) revealed large OP ASD and severe MR with MR jet directed primarily into RA through OP ASD (Figure 1 A, 1 B). In view of these two, less volume was directed towards LV. Patient was operated via standard midline sternotomy with aorto-bicaval cannulation and cardioplegic arrest. Intra-operatively, there was a large ostium primum atrial septal defect (OP-ASD) of size ~ 3×1 cm. No VSD could be appreciated .Left AV valve revealed a double orifice mitral valve (DOMV) (Figure 2 A), with two orifices, a major orifice and a minor orifice, divided by a fibrous bridge. We were unable to categorize the valve leaflets of the major orifice, as per standard classification of left AV valve .On inspection of the subvalvular apparatus, single papillary muscle was present below both the orifices and almost all the chordae were attached to them , making both orifices prone to stenosis after repair. On saline jet test, minor orifice was competent, but gross MR was seen to be emanating from cleft like area in major orifice .The bridge between the two orifices was left untouched. The cleft like area in the major orifice was partially closed with 6/0prolene, using continuous suture technique. After repair, sizing of the two orifices was done with Hegar’s dlilator and the combined orifice area of the two orifices corresponded to z value of 0 according to normogram (Figure 2 B). Saline jet test post mitral valve repair revealed no significant MR. OP-ASD was closed with pericardial patch leaving coronary sinus in RA. Post operative, needle estimation revealed, pulmonary arterial pressure (PAP) of 35/23 mm Hg (29) and left atrial pressure (LAP) of 8 mm Hg. Intra operative TEE (Figure 3 A, B) confirmed no residual ASD, mild MR, no mitral stenosis (MS) and mild tricuspid regurgitation (TR). In view of increased volume load delivered to LV now, the morphology of left AV valve was more appreciable. Post-operative course was uneventful.