肺动脉闭塞可引起病人猝死，小肺动脉闭塞不引起严重的影响。对于心肺系统受损的人肺中动脉分支可引起梗死。肺梗死是出血性梗死，由于肺是双重血液供应的，支气管动脉可继续供血，但不能阻止梗死的发生。
Occlusion of main pulmonary arteries can kill the patient suddenly. Occlusion of small pulmonary arteries has no major immediate effect. Occlusion of a medium-sized branch of pulmonary artery can lead to a pulmonary infarction in a person with compromised cardiac or respiratory status. A pulmonary infarct is hemorrhagic because of the dual blood supply from the non-occluded bronchial arteries which continue to supply blood, but do not prevent the infarction.