Left ventricular rotational abnormalities in patients with transposition of the great arteries late after atrial switch operation: detailed analysis from the CSONGRAD Registry and MAGYAR-Path Study

BACKGROUND: Dextro-transposition of the great arteries (dTGA) is one of the most common cyanotic congenital heart defects, when the origins of the main arteries are switched in position. The present retrospective cohort study aimed three-dimensional speckle-tracking echocardiography-derived determination of apical and basal morphologic left ventricular (mLV) rotations and twist in adults with dTGA late after atrial switch. It was also purposed to compare whether differences in mLV rotational parameters were present in Senning- and Mustard-operated subjects. METHODS: Sixteen dTGA patients were willing to participate late after atrial switch in this study, however, 6 subjects were excluded due to inferior image quality. The remaining group of 10 dTGA patients had a mean age of 29.4±8.8 years (5 males). Their clinical data were from the CSONGRAD Registry. Their results were compared to 24 age- and gender-matched healthy controls with a mean age of 34.4±12.6 years (14 males). RESULTS: From the dTGA patient population, only 5 out of 10 subjects had normally directed mLV rotational mechanics, 5 dTGA cases had significant mLV rotational abnormality with counterclockwise mLV basal rotation in 4 patients (mLV rigid body rotation, mLV-RBR). One patient had complete reversal of apical and basal mLV rotations. Compared to the matched healthy controls, dTGA patients showed mLV-RBR significantly more frequently (50% vs. 0%, P=0.0009) regardless of the fact whether Senning- or Mustard-procedure was performed. dTGA patients with normally directed mLV rotational mechanics proved to have increased mLV basal rotation (−7.9±4.1 vs. −3.7±1.9 degree, P=0.001) with preserved mLV twist (16.4±3.3 vs. 14.0±4.1 degree, P=ns) as compared to matched controls. CONCLUSIONS: Significant mLV rotational abnormalities are present in dTGA late after atrial switch procedures including mLV-RBR and reversed mLV twist. In dTGA patients with normally directed mLV rotational mechanics, mLV basal rotation is increased with preserved mLV twist. Some differences in mLV rotational abnormalities are present between Senning- and Mustard-procedures.