MAGNETIC-RESONANCE-IMAGING DEMONSTRATION OF REMODELING OF THE AORTA FOLLOWING BALLOON ANGIOPLASTY OF DISCRETE NATIVE COARCTATION

Assessment of the hemodynamic and anatomic results following balloon a ngioplasty of discrete native coarctation of the aorta, with particula r attention to ''remodeling,'' has required repeat cardiac catheteriza tion and angiography, which is invasive and has limited resolution. Ei ght patients with hypertension and discrete native coarctation with an otherwise normally developed aortic arch underwent angioplasty at 5.0 +/- 6.8 years of age. Angiographic cross-sectional areas of the aorta indexed to body surface area at the isthmus (I), coarctation site (C) , and 1 cm distal to the coarctation site (Cd) pre- and postangioplast y were compared with MRI-indexed cross-sectional areas 18 +/- 10 month s (MRI-1) and 35 +/- 11 months (MRI-2) postangioplasty. From preangiop lasty to MRI-2, the isthmus was smaller (149 +/- 22 versus 127 +/- 27 mm(2)/m(2); p < 0.05). The coarctation site was larger postangioplasty (25 +/- 9 versus 116 +/- 40 mm(2)/ m(2); p < 0.001) with continued gr owth at latest follow-up (116 +/- 40 versus 164 +/- 36 mm(2)/m(2); p < 0.01). The segment 1 cm distal to the coarctation site continued to d ecrease in area at latest follow-up (267 +/- 78 versus 163 +/- 38 mm(2 )/m(2) p < 0.001). I versus C versus Cd at MRI-2 were similar, whereas postangioplasty and MRI-1 cross-sectional area measurements were sign ificantly different. Following angioplasty of discrete native coarctat ion, the aorta becomes more uniform or undergoes ''remodeling.'' Nonin vasive MRT is an effective means of evaluating the anatomic result fol lowing balloon angioplasty, obviating the need for repeated invasive c ardiac catheterizations.