Altered left ventricular vortex ring formation by 4-dimensional flow magnetic resonance imaging after repair of atrioventricular septal defects.
OBJECTIVE
During normal left ventricular (LV) filling, a vortex ring structure is formed distal to the left atrioventricular valve (LAVV). Vortex structures contribute to efficient flow organization. We aimed to investigate whether LAVV abnormality in patients with a corrected atrioventricular septal defect (AVSD) has an impact on vortex ring formation.


METHODS
Whole-heart 4D flow MRI was performed in 32 patients (age: 26 ± 12 years), and 30 healthy subjects (age: 25 ± 14 years). Vortex ring cores were detected at peak early (E-peak) and peak late filling (A-peak). When present, the 3-dimensional position and orientation of the vortex ring was defined, and the circularity index was calculated. Through-plane flow over the LAVV, and the vortex formation time (VFT), were quantified to analyze the relationship of vortex flow with the inflow jet.


RESULTS
Absence of a vortex ring during E-peak (healthy subjects 0%, vs patients 19%; P = .015), and A-peak (healthy subjects 10% vs patients 44%; P = .008) was more frequent in patients. In 4 patients, this was accompanied by a high VFT (5.1-7.8 vs 2.4 ± 0.6 in healthy subjects), and in another 2 patients with abnormal valve anatomy. In patients compared with controls, the vortex cores had a more-anterior and apical position, closer to the ventricular wall, with a more-elliptical shape and oblique orientation. The shape of the vortex core closely resembled the valve shape, and its orientation was related to the LV inflow direction.


CONCLUSIONS
This study quantitatively shows the influence of abnormal LAVV and LV inflow on 3D vortex ring formation during LV inflow in patients with corrected AVSD, compared with healthy subjects.
Department of Paediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
Emmeline E
EE
Calkoen
Department of Radiology, Division of Image Processing, Leiden University Medical Center, Leiden, The Netherlands.
Mohammed S M
MS
Elbaz
Department of Radiology, Division of Image Processing, Leiden University Medical Center, Leiden, The Netherlands.
Jos J M
JJ
Westenberg
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
Lucia J M
LJ
Kroft
Department of Thoracic Surgery, Leiden University Medical Center, Leiden, The Netherlands.
Mark G
MG
Hazekamp
Department of Paediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: a.roest@lumc.nl.
Arno A W
AA
Roest
Department of Radiology, Division of Image Processing, Leiden University Medical Center, Leiden, The Netherlands.
Rob J
RJ
van der Geest
D000293:Adolescent; D000328:Adult; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D016022:Case-Control Studies; D002648:Child; D016208:Databases, Factual; D005260:Female; D006343:Heart Septal Defects / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D016277:Ventricular Function, Left; D055815:Young Adult
4D flow MRI; atrioventricular septal defect; atrioventricular valves; vortex flow