METHODS: The CS-CMR acquires 2 long-axis and 3 short-axis cine in 1 single breath-hold. To measure RV ejection fraction (RVEF(CS)) and RV volumes, a non-model-based 3D reconstruction software was used (figure). For comparison, a conventional stack of multi-breath-hold short axis cine was acquired. As a reference for the RV stroke volume (RVSV), pulmonary antegrade flow was measured by phase-contrast CMR in the main and both pulmonary branch arteries.
RESULTS: Seventeen patients with no more than trace tricuspid regurgitation with different CHD lesions were included (age 32±14 years; 7 (41%) females, 4 tetralogy of Fallot, 5 Ross, 4 pulmonary stenosis, 2 ventricular and 2 atrial septal defect). CS derived RV enddiastolic volume, RVSV and RVEF were significantly lower than those determined by the standard short axis cines (table). The agreement of RVSV(CS) with total antegrade pulmonary flow determined either in the main pulmonary artery (MPA) or by the sum of antegrade flow in both pulmonary branch arteries (PPA) was superior to that of RVSV(standard) (table).
CONCLUSIONS: CS-CMR allows evaluation of the RV function and volumes in CHD patients. The preliminary data show that the CS-CMR appears to better determine RV stroke volume than standard short axis cines as it avoids misalignment of the different long and short axis cine loops.