Left atrial strain in adults after the arterial switch operation for transposition of the great arteries.

Abstract

No study has focused on left atrial (LA) function assessed by echocardiography in adult patients with simple D-TGA after arterial switch operation (ASO). We aimed to describe LA strain parameters in these patients. A prospective cohort study including 42 adult patients with simple D-TGA after ASO and 33 aged-matched controls. Phasic LA and LV global longitudinal strain (GLS) were obtained by transthoracic 2D-speckle tracking echocardiography (STE). Volumetric and functional analysis of LA and LV were also evaluated by 2D and 3D analysis. A multivariable model was performed to investigate the variables that best differentiate patients with D-TGA from healthy controls. LA strain parameters in D-TGA patients were within the normal range described for healthy subjects. However, the three LA strain parameters (Reservoir, Conduit, and Contraction) were lower in patients (LASr: 31.13±7.67vs. 49.71±8.38; LAS cd: -22.91±5.69vs. -34.55±6.54; LASct: -8.14±4.93vs. -15.15±6.07, p<.001 for all three comparisons). LA volumes were similar between patients and controls. LV-GLS remained significantly lower in the D-TGA group than in controls (-17.29±2.68vs. -21.98±1.84, p<.001). D-TGA patients had evidence of worse LV ejection fraction measured by the Teichholz method (63.38±8.23vs. 69.28±5.92, p=.001) and 3D analysis (57.97%±4.16vs. 60.67±3.39, p=.011) and diastolic dysfunction as compared to healthy controls. LV-GLS and conduit LAS were the variables best differentiating patients with D-TGA from healthy controls. LA strain is impaired in young adults with simple D-TGA late after the ASO, probably in agreement with some degree of LV dysfunction previously described.