MAPT and Alzheimer disease: An early pathology study observed an association between LAD and AD pathologies67 while clinical studies showed an association between AF and AD.68 A recent clinical study further showed an association between atrial volume/atrial cardiopathy with increased cerebral Aβ load.69 A possible explanation for such findings is that LAD and heart–brain dysfunctions may associate with cerebral hypoperfusion, hence affecting BBB integrity and neurovascular unit function, resulting in Aβ/tau accumulation (Figure 2).70