Long-term MRI Follow-up of Repaired Coarctation of the Aorta

Abstract

Early operative repair of coarctation of the aorta (CoA) is associated with improved patient prognosis; however the rates of re-coarctation in follow-up are variable across institutions. We investigated the impact of early CoA repair (<2 years) in 47 consecutive subjects (17.2± 8.1 years post-repair) referred forMRI. Therewere 42 cases of end-to-end repair and 5 cases of subclavian flap repair. Re-intervention with balloon angioplasty post-surgical repair was performed in 12 cases, with further repeat angioplasty performed in 1 case. Amongst the subjects, 36% had a bicuspid aortic valve (BAV) and 32% were hypertensive at rest. The mean indexed left ventricular mass and ejection fraction was 71± 16 g/m2 and 68± 7%, respectively. Recoarctation was considered moderate or severe in 36%, mild in 32% and no re-coarctation identified in 32%. Poststenotic dilatation was found in 23% of cases. Amongst those with BAV there was a higher rate of moderate or severe re-coarctation (58% vs. 33%), larger aortic sinus We retrospectively identified consecutive subjectswith PR as a result of pulmonary stenosis (PS) treated with valvotomy (n= 30, 27± 2 years) and age-matched them with subjects who have ToF and inwhom a trans-annular patch procedure (n= 30, 25± 1 years) was performed. All subjects were referred for MRI quantification of “free PR” detected on 2D echocardiography between 2003 and 2007. Moderate to severe PR was identified in both groups (PS: 38± 2% vs. ToF: 41± 1.5%, p=NS). RV volumes were consistently lower in the PS group than for ToF (RV EDV: 217± 8ml vs. 256± 12ml, respectively, p< 0.01 and RV ESV: 90± 5ml vs. 132± 9ml, respectively, p< 0.001). Further, RV systolic function was significantly higher in the PS group than in ToF (59± 1% vs. 50± 1%, respectively, p< 0.001). Qualitatively, 63% of PS subjects had right ventricular hypertrophy on MR imaging compared to 88% of subjects with ToF. The mean pulmonary artery diameter was similar in both groups (PS: 28± 0.8mm vs. 29± 1mm, p=NS). Left ventricular systolic function was also higher in the PS group compared to ToF (66± 2% vs. 59± 1%, p< 0.001). SubjectswithPR resulting fromvalvotomy for PShave less RV dilatation and better RV and LV systolic function compared to matched subjects with ToF. These findings may have clinical implications when advising on ventricular volume indications for the management of chronic PR.