Histological assessment of cardiac amyloidosis in patients undergoing transcatheter aortic valve replacement

Area of Science:

• Cardiology
• Pathology
• Biomarker Discovery

Background:

• Co-prevalence of aortic stenosis (AS) and cardiac amyloidosis (CA) varies significantly in existing literature.
• Transcatheter aortic valve replacement (TAVR) provides an opportunity to study this co-prevalence.
• Histological analysis is crucial for accurate diagnosis of co-existing conditions.

Purpose of the Study:

• To determine the histological co-prevalence of AS and CA in patients undergoing TAVR.
• To develop a predictive algorithm for identifying AS patients with concomitant CA.
• To investigate clinical and proteomic differences between patients with AS alone and those with both AS and CA.

Main Methods:

• Prospective, monocentric study analyzing endomyocardial biopsies from 162 TAVR patients.
• Histological examination using H&E, EVG, and Congo red staining.
• Analysis of clinical parameters, serum biomarkers (proteomics), and development of a screening algorithm.

Main Results:

• The co-prevalence of AS and CA was found to be 4.9%.
• Patients with concomitant CA exhibited higher NT-proBNP, lower voltage-to-mass ratio, and lower transaortic gradients.
• Concomitant CA was associated with increased risk of post-procedural acute kidney injury and sudden cardiac death (SCD).
• A proposed algorithm using clinical parameters achieved 66.6% sensitivity and 98.1% specificity for CA screening in AS patients.

Conclusions:

• The actual co-prevalence of AS and CA is lower than previously suggested.
• AS patients with concomitant CA have a higher risk of SCD, despite good overall 1-year survival.
• A novel multimodal algorithm can effectively screen for CA in AS patients using routine clinical data.
• Proteomic biomarkers show potential for future diagnostic improvements.