Spontaneous pulmonary artery thrombosis in neonates is rare and can be life-threatening. Clinical presentation may mimic pulmonary hypertension or CHD. Further, not all children present with identifiable risk factors. We report the case of two infants with pulmonary artery thromboses who underwent rapid diagnosis and therapy, one with percutaneous intervention and the other with anticoagulation. We also conducted a literature review to highlight the importance of early identification and referral to a centre capable of performing appropriate medical and interventional therapies.