Multimodality imaging methods and systemic biomarkers in classical low-flow low-gradient aortic stenosis: Key...

Area of Science:

• Cardiology
• Medical Imaging
• Biomarkers

Background:

• Elevated B-type natriuretic peptide (BNP) and high-sensitivity troponin I (hsTnI) are linked to poorer outcomes in patients with low-flow, low-gradient aortic stenosis (LFLG-AS).
• Understanding the relationship between these biomarkers and cardiac structure/function is crucial for risk stratification in LFLG-AS.

Purpose of the Study:

• To evaluate multimodality imaging findings in relation to systemic biomarkers, specifically high-sensitivity troponin I (hsTnI) and B-type natriuretic peptide (BNP) levels.
• To assess cardiac remodeling and fibrosis in patients with LFLG-AS based on hsTnI and BNP levels.

Main Methods:

• A prospective study included 49 LFLG-AS patients undergoing coronary angiography, cardiac magnetic resonance (CMR) with T1 mapping, echocardiography, and dobutamine stress echocardiography.
• Patients were stratified into three groups based on median hsTnI and BNP levels: Group 1 (low levels), Group 2 (intermediate levels), and Group 3 (high levels of both biomarkers).

Main Results:

• Group 3 patients exhibited lower valvuloarterial impedance and left ventricular ejection fraction (LVEF) on echocardiography compared to other groups.
• CMR revealed progressive increases in right and left ventricular volumes and worsening LVEF and right ventricular EF from Group 1 to Group 3.
• Myocardial fibrosis, assessed by extracellular volume fraction (ECV) and indexed ECV (iECV), significantly increased from Group 1 to Group 3.

Conclusions:

• Higher levels of BNP and hsTnI in LFLG-AS patients are associated with more pronounced multi-modality imaging evidence of cardiac remodeling.
• Elevated BNP and hsTnI levels indicate increased myocardial fibrosis in LFLG-AS, suggesting a worse cardiac phenotype.