 The study plans to enroll subjects with alpha-1 antitrypsin deficiency-associated lung disease PiZZ phenotype to perform a cross-over randomized controlled trial RCT of aspirin compared to placebo to test the hypotheses that aspirin is effective in improving blood flow in the lungs and reducing damage to the endothelial cells. Subjects will be randomized to receive aspirin or placebo for 2 weeks. There will be a 2-week washout period, then the participant will be crossed over to receive the other treatment those who received aspirin first will receive the placebo and those who received the placebo first will receive aspirin. 