Evaluation of sampling density on the accuracy of aortic pulse wave velocity from velocity-encoded MRI in patients with Marfan syndrome.
OBJECTIVE
To evaluate the effect of spatial (ie, number of sampling locations along the aorta) and temporal sampling density on aortic pulse wave velocity (PWV) assessment from velocity-encoded MRI in patients with Marfan syndrome (MFS).


METHODS
Twenty-three MFS patients (12 men, mean age 36 ± 14 years) were included. Three PWV-methods were evaluated: 1) reference PWV(i.p.) from in-plane velocity-encoded MRI with dense temporal and spatial sampling; 2) conventional PWV(t.p.) from through-plane velocity-encoded MRI with dense temporal but sparse spatial sampling at three aortic locations; 3) EPI-accelerated PWV(t.p.) with sparse temporal but improved spatial sampling at five aortic locations with acceleration by echo-planar imaging (EPI).


RESULTS
Despite inferior temporal resolution, EPI-accelerated PWV(t.p.) showed stronger correlation (r = 0.92 vs. r = 0.65, P = 0.03) with reference PWV(i.p.) in the total aorta, with less error (8% vs. 16%) and variation (11% vs. 27%) as compared to conventional PWV(t.p.) . In the aortic arch, correlation was comparable for both EPI-accelerated and conventional PWV(t.p.) with reference PWV(i.p.) (r = 0.66 vs. r = 0.67, P = 0.46), albeit 92% scan-time reduction by EPI-acceleration.


CONCLUSIONS
Improving spatial sampling density by adding two acquisition planes along the aorta results in more accurate PWV assessment, even when temporal resolution decreases. For regional PWV assessment in the aortic arch, EPI-accelerated and conventional PWV assessment are comparably accurate. Scan-time reduction makes EPI-accelerated PWV assessment the preferred method of choice.
Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands. e.s.j.kroner@lumc.nl
Eleanore S J
ES
Kröner
Rob J
RJ
van der Geest
Arthur J H A
AJ
Scholte
Lucia J M
LJ
Kroft
Pieter J
PJ
van den Boogaard
Dennis
D
Hendriksen
Hildo J
HJ
Lamb
Hans-Marc J
HM
Siebelink
Barbara J M
BJ
Mulder
Maarten
M
Groenink
Teodora
T
Radonic
Yvonne
Y
Hilhorst-Hofstee
Jeroen J
JJ
Bax
Ernst E
EE
van der Wall
Albert
A
de Roos
Johan H C
JH
Reiber
Jos J M
JJ
Westenberg
D000328:Adult; D000465:Algorithms; D001011:Aorta / Q000473:pathology* / Q000503:physiopathology*; D001783:Blood Flow Velocity; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008382:Marfan Syndrome / Q000473:pathology* / Q000503:physiopathology*; D063177:Pulse Wave Analysis / Q000379:methods*; D015203:Reproducibility of Results; D018401:Sample Size; D012680:Sensitivity and Specificity