Evaluation of aortic coarctation after surgical repair: role of magnetic resonance imaging and Doppler ultrasound.

Abstract

Cross sectional echocardiography from a suprastemal approach usually allows visualisation of the aortic arch and its branches and detects aortic coarctation.i Image quality is often poor, however, (particularly in older patients) after coarctation repair because of the small acoustic window and the long distance between the transducer position and the isthmic region.78 Furthermore, assessment by ultrasound is disappointing because the acoustic window is inadequate when a prosthetic vascular conduit is used for surgical correction of coarctation.9 Recent studies cast doubt on the reliability of measurements of luminal diameter by cross sectional echocardiography without additional colour Doppler flow mapping, which enhances the contrast between the vessel lumen and its wall.1' Several groups have reported on the usefulness of MRI in detecting morphological anomalies of the great vessels, especially in aortic coarctation."1-13Diminished pulses in the lower limbs after coarctation repair suggests restenosis or persisting stenosis. Gradients can be measured from blood pressures in the upper and lower limbs. Flow velocities in the descending aorta distal and proximal to the isthmic region can be measured throughout the cardiac cycle by Doppler ultrasound and it has become clear that not only Doppler determined velocities in the descending aorta but also the flow profile are important in the assessment of the functional state after coarctation repair. 1416 We have evaluated whether the morphological situation after surgical repair of aortic coarctation can be properly demonstrated and measured by MRI and cross sectional echocardiography. We compared morphometric data with the functional data obtained by oscillometric measurement of blood pressure and Doppler ultrasound measurements.

Coarctation of the aorta: comparison of aortic dimensions between conventional MR imaging, 3D MR angiography, and conventional angiography

“…Conventional angiography was classically the standard of reference for aortic arch visualisation; however, it is an invasive method with considerable radiation exposure that carries risks such as haemorrhage, arterial injury, thrombosis and adverse reactions to iodinated contrast material [1]. Echocardiography is an alternative, non-invasive method that is widely employed, but it is sometimes difficult to obtain good visualisation of the site of coarctation because of poor acoustic window, the long distance between the transducer and the isthmic region, and poor patient cooperation [2,3,4,5]. Magnetic resonance imaging study is another alternative method with spin-echo (SE) images showing excellent anatomical views of the aorta and cine-MR imaging sequences detecting turbulent jets of blood at the site of coarctation.…”

Steady‐state free‐precession (SSFP) cine MRI in distinguishing normal and bicuspid aortic valves

“…MRI is established as one of the most accurate noninvasive modalities in the study of aortic diseases (7,8). Breathhold cine sequences using steady-state free-precession (SSFP) acquisitions, e.g., true fast imaging with steady-state precession (TrueFISP) (Siemens Medical Systems, Erlangen, Germany) combine the advantage of short acquisition times and high signal-to-noise ratio, thus optimizing blood-myocardium contrast (9).…”

Evaluation of Magnetic Resonance Imaging in Coarctation of the Aorta: The Importance of Multiple Imaging Planes

“…Magnetic resonance imaging has been shown to be comparable to angiography and consistently better than echocardiography in identifying the anatomy of coarctation [3,[5][6]. Long term studies of children treated for coarctation of the aorta show a high incidence of recoarctation [9,13] and significant incidence of aneurysm formation [14,15], suggesting the need for vigilant follow-up by noninvasive imaging such as magnetic resonance imaging.…”

“…Aneurysms were detected in 15 children, but in both views in only three children. Recoarctation and aneurysm detection were both statistically more likely to be detected if oblique coronal and oblique parasagittal views were obtained, indicating that multiple imaging planes are necessary to completely evaluate magnetic resonance imaging of coarctation.Magnetic resonance imaging has become established for the evaluation of the aorta following surgery [1][2][3][4][5] or balloon angioplasty [6][7][8]. Magnetic resonance imaging is noninvasive and yields morphologic results similar to angiography and frequently superior to ultrasound.…”

“…Magnetic resonance imaging has become established for the evaluation of the aorta following surgery [1][2][3][4][5] or balloon angioplasty [6][7][8]. Magnetic resonance imaging is noninvasive and yields morphologic results similar to angiography and frequently superior to ultrasound.…”