Discussion
Dextrocardia is a rare congenital cardiac anomaly where the base-apex axis of the heart is directed to the right side. The atrial situs can be situs solitus, situs inversus, or situs ambiguous of which situs inversus (mirror image dextrocardia) is more common (40%). If all the visceral organs also get mirrored, then it is called dextrocardia with situs inversus totalis. In dextrocardia with situs inversus, around 10% of the cases are associated with other congenital cardiac anomalies [2].
Our patient had a typical case of dextrocardia with situs inversus totalis (all visceral organs were mirror images of the normal) and presented an aortic biological prosthesis dysfunction requiring a redo aortic valve replacement. The anatomy of the patient is almost challenging in the case with dextrocardia and decision for the surgeon where to stand during surgery is crucial.
Some approaches have been described about patients with dextrocardia with situs inversus totalis for valve replacement but still redo cardiac surgery is rare. Haldar et al [3] reported a case of aortic and mitral valve replacement in a patient with dextrocardia and situs inversus totalis in which they stood on the left side of the patient. Sahin and colleagues [4] described a transseptal approach for mitral valve replacement. Saad et al [5] adressed the position of the surgeon in dextrocardia and situs inversus. Similar to our case, Altarabsheh et al [6] reported a left side approach for aortic valve replacement in a patient with dextrocardia and situs inversus, proposing this operative setting for patients with such unusual anatomy.
A meticulous pre-operative surgical plan involving the whole team was very important for a smooth intra-operative course and a favourable outcome. Regarding intraoperative strategy about the position of surgeon for cannulation and aortic valve approach, we performed bicaval cannulation, prosthesis removing and new aortic bioprosthesis insertion with the main surgeon standing on the left side of the patient. We believed this surgical team arrangement added much to the technical ease for the surgery, since the anatomy was opposite to what our minds are used to.
In addition, since it was a redo cardiac surgery with an uncommon anatomy, CT scan played a crucial role for a proper preoperative anatomical evaluation of all the great vessels, the heart, possible associated anomalies and to plan our cannulation strategy. Also, CT scan permitted to minimize risk of re-entry injury because it could identify potential adherence of mediastinal structures to the undersurface of the sternum.
Our patient had dextrocardia with situs inversus totalis requiring a redo aortic valve surgery. CT scan had an important role for operative planning, which contributed substantially for the good result of the operation. Our left side approach provided excellent exposure for redo aortic valve replacement in this scenario.