Abstract 13750: Cardiac Magnetic Resonance to Predict Coronary Artery Compression in Patients Undergoing Transcatheter Pulmonary Valve Implantation Into Conduits

Introduction: Transcatheter pulmonary valve implantation (TPVi) is a widely available option to treat right ventricular outflow tract (RVOT) conduits, but coronary artery compression is an absolute contraindication. Cardiac magnetic resonance (CMR) may evaluate coronary anatomy, but its utility in predicting coronary compression is not well established. Hypothesis: CMR prior to TPVi can accurately predict coronary compression risk. Methods: We analyzed all patients with a recent CMR (≤ 12 months) and attempted TPVi in an RVOT conduit at 9 centers from 2007-2016. A core lab reviewed all CMRs for the shortest orthogonal distance from a coronary artery to the conduit, the shortest distance from a coronary artery to the most stenotic area of the conduit, and subjective assessment of coronary compression risk. Receiver operating characteristic curve was used to determine optimal predictive distances. Univariate and independent associations of the distances and qualitative assessment with coronary compression were examined using logistic regression. Results: Of 231 patients (62% male, median age 19.0 years), TPVi was successful in 198 (86%); in 24 (10%) balloon testing (documented coronary compression or high risk) precluded implantation. Distance to the RV to PA conduit ≤ 2.1 mm (area under the curve [AUC] 0.70) and distance to most stenotic area ≤ 13.1 mm (AUC 0.69) predicted coronary compression (Table). Subjective assessment had the highest AUC (0.78), with 96% negative predictive value. Both distances and qualitative assessment remained independently associated with coronary compression when controlling for abnormal coronary anatomy. Conclusions: CMR can predict the risk of coronary compression during TPVi in RVOT conduits but cannot completely exclude the risk of coronary compression. CMR may assist in patient selection and counselling families prior to TPVi, although balloon testing prior to TPVi remains essential.