What does this mean other anomalies of pulmonary artery and pulmonary circulation with collateral flow?

Partial description: That sounds like only part of a larger description? Anomalies usually refers to a congenital or birth defect. Collateral flow means blood is reaching its target tissue by alternate routes. Taken all together, my guess is: there is some congenital obstruction or diversion of blood from the right ventricle thru the lungs that, nonetheless, has found a way to get through.