Quantification of shunt volumes in congenital heart diseases using a breath-hold MR phase contrast technique--comparison with oximetry.
OBJECTIVE
Comparison of breath-hold MR phase contrast technique in the estimation of cardiac shunt volumes with the invasive oximetric technique.


RESULTS
Seventeen patients with various cardiac shunts (10 ASD, 3 VSD, 1 PDA, 3 PFO) and five healthy volunteers were investigated using a 1.5 Tesla system. The mean flow velocity, the mean volume flow and the transverse area in the ascending aorta and the left and right pulmonary artery were measured using the MR phase contrast breath-hold technique (through plane, FLASH 2D-sequence, TR/TE 11/5 ms, phase length 106 ms, VENC 250 cm/s). The ratio of mean flow in the pulmonary (Qp: sum of mean flows in the left and right pulmonary arteries) and the systemic circulation (Qs: mean flow in the ascending aorta) was calculated and compared with invasively measured Qp:Qs ratios. Oximetry was performed within 24 h of the MR investigation. The non-invasive shunt measurement in the 17 patients showed a mean Qp:Qs ratio of 2.00 +/- 0.86. Comparing the MR data with the invasively measured Qp:Qs showed a correlation coefficient of r = 0.91 (p < 0.001).


CONCLUSIONS
Cardiac shunt volumes can be measured reliably using a shorter acquisition time with breath-hold MR phase contrast technique.
2nd Medical Clinic, Johannes Gutenberg University Hospital Mainz, Germany. steffen.petersen@gmx.de
Steffen E
SE
Petersen
Thomas
T
Voigtländer
Karl-Friedrich
KF
Kreitner
Peter
P
Kalden
Thomas
T
Wittlinger
Jürgen
J
Scharhag
Georg
G
Horstick
Dietmar
D
Becker
Gerhard
G
Hommel
Manfred
M
Thelen
Jürgen
J
Meyer
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D006328:Cardiac Catheterization; D016022:Case-Control Studies; D005260:Female; D006330:Heart Defects, Congenital / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation; D011652:Pulmonary Circulation / Q000502:physiology