Abstract 4686: Noncontrast Three Dimensional Dark Blood Magnetic Resonance Imaging in Adult Congenital Heart Disease Patients After Transcatheter Intervention
Background: Adults with congenital heart disease (ACHD) often require transcatheter therapies as a result of residual lesions. CT is well-suited for evaluation of stents but exposes young adults to radiation. Gradient echo MRI suffers from artifact limiting assessment of stented segments. We investigate the use of a novel 3D turbo spin echo (TSE) MRI sequence in these patients.
Methods: ACHD patients presenting for MRI with prior interventions underwent an additional T1-weighted 3D dark blood navigator respiratory gated TSE scan on a1.5 Tesla system. Type of CHD, prior CT, radiation dose, length of time between examinations, and luminal diameters on each study were obtained. Continuous variables analyzed using Student’s t-test and Bland-Altman plots.
Results: Eleven patients underwent both MRI and CT. Diagnoses were coarctation of the aorta (n=6) and tetralogy of Fallot (n=5) with intervention in the aorta or pulmonary arteries respectively. Average radiation dose was 19.57mSv; average time between CT and MRI was 99 ± 160 days. Luminal diameters of stented vessels correlated closely between TSE MRI and CT (r2= .85) with a small bias toward overestimation with MRI (mean 22.4 +/− 4.3 mm and 20.9 +/− 3.7 mm, p< .01). There were no cases of in-stent stenosis demonstrated by CT.
Conclusion: Metallic artifact is significantly reduced with 3D navigator respiratory gated TSE MRI allowing visualization of anatomy in the vicinity of stents, providing a potential method for assessment of complex anatomy without radiation exposure or use of contrast agents. Further studies of this technique are warranted, particularly in patients with in-stent stenosis.