21 year-old healthy female volunteer. Streamline visualization in a right ventricular (RV) systolic phase. Right atrial (RA) filling primarily during systole, which is characterized by a single clockwise vortical flow pattern (A, curved dashed arrow). Simultaneously, smooth flow patterns are present in the main (MPA), right (RPA), and left (LPA) pulmonary arteries (B, curved solid arrows). Color-coding was achieved with respect the absolute acquired velocities.