Poor R-wave progression associates with cerebral amyloid deposition: A potential link between heart and brain.

BackgroundAmyloid deposition is a key pathologic hallmark of Alzheimer's disease (AD). Since cardiac amyloidosis also involves abnormal amyloid accumulation, shared proteinopathy mechanisms may underlie both conditions.ObjectiveWe investigated whether brain amyloidosis on PET imaging is associated with electrocardiogram (EKG) findings of cardiac involvement by AD pathology.MethodsWe included 191 participants (mean age 66 ± 13.0 years) in our analysis, who underwent amyloid PET imaging and EKG within one year. EKG abnormalities (including low QRS voltage, poor R-wave progression (PRWP), bundle branch block, and sinus bradycardia) were assessed for associations with brain amyloid deposition, quantified in Centiloids, and cognitive function. A subset (n = 164) also underwent 18F-MK6240 tau PET, and the relationship between these EKG abnormalities and tau deposition was also assessed.ResultsPRWP was associated with greater brain amyloid deposition (coefficient = 45 ± 12.15, p < 0.001) and worse cognition on the Clinical Dementia Rating scale (coefficient = 0.22 ± 0.098, p = 0.027). There was a trend for higher likelihood of cortical tau deposition with PRWP (odds ratio = 3.66, p = 0.05). Sinus bradycardia was associated with higher likelihood of cortical tau deposition (odds ratio = 2.81, p = 0.009). Other EKG abnormalities were not significantly associated with brain amyloid/tau deposition or cognition.ConclusionsPRWP and sinus bradycardia were found to be associated with AD pathology in the brain. These findings warrant further investigation into how cardiac electrophysiologic abnormalities may reflect a possible link between brain and cardiac pathologies or AD-associated cardiac dysfunction.