Juxtaposition of atrial appendages: Evaluation of cardiovascular morphology and associated anomalies on multidetector computed tomography angiography.

Objective: To evaluate the morphology and associated cardiovascular abnormalities in patients with juxtaposition of atrial appendages (JAA) on multidetector computed tomography (MDCT) angiography.

Methods: We performed the retrospective study at a tertiary referral center to identify patients diagnosed with JAA on MDCT angiography using dual-source CT scanner between January 2014 and April 2021. The various imaging abnormalities evaluated included the type of JAA, morphological and positional classification of JAA, atrial situs, cardiac position, atrioventricular and ventriculoarterial connections, great vessel relationship, and other associated cardiovascular anomalies.

Results: We identified 129 patients with JAA. Left-sided juxtaposition was seen in 124 (96.1%) patients while right-sided juxtaposition was seen in 5 (3.9%) patients. Among patients with left-sided juxtaposition, frequent cardiovascular associations included outflow tract malformations (100%), hypoplastic right ventricle (40.3%), tricuspid atresia (32.2%), and right-sided heart (19.4%). The most frequent outflow tract malformation was double outlet right ventricle (DORV; 60.5%) followed by transposition of great arteries (20.1%) and transposed aorta with pulmonary atresia (18.5%). In patients with right-sided juxtaposition, outflow tract malformation was seen in three (60%) patients with one (20%) patient each showing DORV, transposed aorta with pulmonary atresia, and tetralogy of Fallot, respectively.

Conclusions: The identification of JAA on MDCT angiography suggests coexistence of various complex congenital heart diseases, especially outflow tract malformations. A meticulous search is imperative to identify this anomaly before interventional or surgical procedures to avoid complications.