Determining patterns of vascular function and structure in wild-type transthyretin cardiac amyloidosis. A comparative...

Area of Science:

• Cardiovascular Medicine
• Nephrology
• Vascular Biology

Background:

• The effects of wild-type transthyretin-related cardiac amyloidosis (ATTRwt) on peripheral vascular measures are not well understood.
• ATTRwt shares a similar cardiac phenotype with other conditions, necessitating comparative studies of vascular dysfunction.

Purpose of the Study:

• To investigate peripheral vascular dysfunction patterns in patients with ATTRwt.
• To compare vascular measures in ATTRwt patients against reference populations and those with similar cardiac conditions like AL amyloidosis and heart failure with preserved ejection fraction (HFpEF).

Main Methods:

• Peripheral vascular assessments were performed on treatment-naïve ATTRwt patients (n=32).
• Comparisons were made with a non-amyloidosis reference group (n=32), systemic AL amyloidosis patients (n=32), cardiac AL amyloidosis (AL-HF, n=23), and HFpEF patients (n=16).
• Methods included carotid ultrasonography, flow-mediated dilation (FMD), arterial stiffness, and aortic hemodynamics (Tr/HR).

Main Results:

• ATTRwt patients exhibited lower peripheral and aortic blood pressure (BP) and a longer heart rate-adjusted time of return of reflected waves (Tr/HR) compared to the reference group, AL, AL-HF, and HFpEF.
• Flow-mediated dilation (FMD) was lower in ATTRwt compared to AL-HF.
• ROC analysis demonstrated Tr/HR's high sensitivity and specificity in discriminating ATTRwt from AL-HF and HFpEF.

Conclusions:

• ATTRwt patients possess a distinct peripheral vascular signature characterized by lower BP, prolonged Tr/HR, and preserved FMD relative to the reference population.
• This vascular fingerprint differs significantly from that observed in AL-HF and HFpEF, suggesting unique pathophysiological mechanisms.
• The findings highlight the potential of Tr/HR and FMD in differentiating ATTRwt from other cardiac conditions.