NPPA and atrial fibrillation: Localized atrial amyloid deposits derived from atrial natriuretic peptide are associated with atrial fibrillation, notably postoperatively,9,38 and become ubiquitous with age, being present at autopsy in 80% of people >70 years of age.39,40 The significance and causality of atrial natriuretic peptide amyloid deposits remain unknown.