Comparison of half-turned truncal switch and conventional operations

Abstract

Objectives: To compare conventional procedures with the half-turned truncal switch operation (HTTSO) for the management of complete transposition of the great arteries with left ventricular outflow tract (LVOT) obstruction using time-resolved 3-dimensional magnetic resonance phase-contrast imaging.

Methods: We identified 2 cases that underwent the Rastelli procedure and one case that underwent the Réparation a l'étage ventriculaire before 2002 [conventional procedures group (group C)], and 16 cases of HTTSO that were performed between 2002 and 2020 [HTTSO group (group H)]. Postoperative haemodynamics were assessed using time-resolved 3-dimensional magnetic resonance phase-contrast imaging in cases in both groups.

Results: The median follow-up period was 20.4 years in group C, and 6.1 years in group H. In group C, all 3 patients underwent reoperation because of postoperative right ventricular outflow tract obstruction and/or insufficiency. In addition, permanent pacemaker implantation was needed in 1 patient because of complete atrioventricular block complicated by ventricular septal defect enlargement. In group H, reoperation for LVOT/right ventricular outflow tract obstruction was not needed. A time-resolved 3-dimensional magnetic resonance phase-contrast imaging examination revealed high energy loss and wall shear stress in the winding LVOT in the group C. In contrast, low energy loss and wall shear stress, with straight and smooth LVOT, were identified in group H.

Conclusions: HTTSO was shown to be superior to conventional procedures because a straight and wide LVOT could be obtained. Therefore, HTTSO should be the first choice for complete transposition of the great arteries with LVOT obstruction.

Keywords: Complete transposition of the great arteries with left ventricular outflow tract obstruction; Nikaidoh; Rastelli; Time-resolved 3-dimensional magnetic resonance phase-contrast imaging; Truncal switch.