Systemic ventricular flow pattern disorder in d-TGA patients – a 4D-

flow MRI study

ESPR 2019

Dr Fraser Callaghan

B. Burkhardt, E.R. Valsangiacomo Buechel, C. J. Kellenberger, J. Geiger

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 2

Systemic ventricular flow pattern disorder in d-TGA patients – a 4D-

flow MRI study

Adapted from: Dasgupta, S. et al. Evaluation of the Cyanotic Newborn:

Part 2--A Cardiologists Perspective. NeoReviews 2016

D-TGA Arterial Switch Atrial Switch

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 3

Normal and d-TGA patients – LV paths derived from 4D-flow MRI

Control Arterial Switch Atrial Switch

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 4

Subject cohort and systemic ventricle volumetric assessment

N (%male) Age (yrs) BSA EDV / BSA SV / BSA EF

Arterial switch 11(63%) 12.6±4.8 1.29±0.3 85.0±10.3 50.9±8.1 59.7±5.5

Atrial switch 10 (70%) 34.4±6.7*** 1.81±0.16** 121.1±34.2** 51.6±14.3 42.6±3.7***

Controls 10 (70%) 11.7±3.4 1.36±0.3 76.9±13.8 44.9±8.2 58.4±3.9

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 5

Systemic ventricle flow energetics

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 7

Flow disorder and energetics

Disordered flow (mixing) yields high viscous energy losses.

High viscous energy loss leads to increasedventricle work requirementsSvalbring, PlosOne, 2016

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 8

Flow disorder and energetics

Disordered flow (mixing) yields high viscous energy losses.

High viscous energy loss leads to increasedventricle work requirements

Ordered flow.

Low viscous energy loss

Disordered flow.

High viscous energy loss

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 9

Flow disorder and energetics

Ordered flow.

Low viscous energy loss

Disordered flow.

High viscous energy loss

Disordered flow.

High viscous energy loss

Ordered flow.

Low viscous energy loss

d-TGA Atrial switch correction d-TGA Arterial switch correction

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 10

Flow disorder and energetics

Disordered flow (mixing) yields high viscous energy losses.

High viscous energy loss leads to increasedventricle work requirements

Ordered flow.

Low viscous energy loss

Disordered flow.

High viscous energy loss

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 11

Subject specific assessment of corrected d-TGA patients using 4D-

flow MRI

Disordered flow (mixing) yields high viscous energy losses• Mixing of ventricle flow components obvious with 4D-flow MRI• Viscous energy losses appear elevated due to this mixing• Viscous energy losses appear to correlate with increased EDV

High viscous energy loss leads to increased ventricle work requirements• Larger population studies• Longitudinal studies

4D-flow MRI assessment of d-TGA | Dr. Fraser Callaghan | ESPR 2019 12

Thank you for your attention

Cardiac MR team at Children’s hospital Zurich

Prof. Christian KellenbergerProf. Emanuela Valsangiacomo BuechelDr. Barbara BurkhardtDr Julia Geiger