Mohammed Mustafa

Background The electrocardiogram (ECG) is routinely used in patients with suspected infiltrative cardiomyopathies; heart diseases characterized by the abnormal deposition of pathological substances in the myocardium. This study presents a review of ECG features attributable to various infiltrative cardiomyopathies and analyzes the prevalence and overlap of electrocardiographic abnormalities in patients with adjudicated CHF. Results The study included 573 consecutive CHF patients without severe aortic stenosis, further stratified by LV hypertrophy (LVH) and preserved or decreased LV ejection fraction. Comprehensive ECG analysis revealed at least one ECG abnormality typically associated with infiltrative cardiomyopathies in 95% of patients, and more than one ECG abnormality in 70%. An average number of ECG abnormalities was 2.2 ± 1.2 per patient. There was substantial overlap in ECG abnormalities in individual patients, particularly those attributable to Fabry’s disease and hemochromatosis (51.5%) or cardiac amyloidosis (46.1%), and hemochromatosis and cardiac amyloidosis (44.2%). Prevalence of various ECG abnormalities was similar across various patient demographics and co-morbidities, including LVH status and/or history of CAD which did not increase the number of ECG abnormalities (2.155 ± 1.238 vs. 2.228 ± 1.192 in patients without CAD history, p = 0.969). Patients with reduced LV ejection fraction had a higher prevalence of widened QRS and premature ventricular complexes. Conclusion ECG abnormalities attributable to infiltrative cardiomyopathies are common in heart failure patients, with a significant overlap in findings classically attributed to various infiltrative cardiomyopathies. The presence of LVH and decreased LV ejection fraction do not significantly affect the prevalence of ECG abnormalities.

HIV-associated neurocognitive disorder (HAND) and Alzheimer’s disease (AD) are two neurocognitive disorders with overlapping clinical presentations and pathophysiology. The two have been thought to be two separate entities. However, the introduction and widespread use of antiretroviral therapy (ART) has altered the clinical manifestations of HAND, shifting from a pattern of subcortical dementia to one more akin to cortical dementia, resembling AD. Thus, the line between the two disease entities is not clear-cut. In this review, we discuss the concept of Alzheimer’s disease-like dementia (ADLD) in HIV, which describes this phenomenon. While the mechanisms of HIV-associated ADLD remain to be elucidated, potential mechanisms include HIV-specific pathways, including epigenetic imprinting from initial viral infection, persistent and low viral load (which can only be detected by ultra-sensitive PCR), HIV-related inflammation, and putative pathways underlying traditional AD risk factors. Importantly, we have shown that HIV-specific microRNAs (miRs) encapsulated in extracellular vesicles (EV-miRs) play an important role in mediating the detrimental effects in the cardiovascular system. A useful preclinical model to study ADLD would be to expose AD mice to HIV-positive EVs to identify candidate EV-miRs that mediate the HIV-specific effects underlying ADLD. Characterization of the candidate EV-miRs may provide novel therapeutic armamentaria for ADLD.