Differentiating Left Ventricular Remodeling in Aortic Stenosis From Systemic Hypertension.

Area of Science:

• Cardiovascular Imaging
• Cardiac Mechanics
• Geometric Remodeling

Background:

• Left ventricular (LV) hypertrophy is common in aortic stenosis (AS) and systemic hypertension (HTN).
• Differentiating the causes of LV hypertrophy between AS and HTN is clinically challenging.
• Understanding distinct geometric remodeling patterns is crucial for diagnosis and management.

Purpose of the Study:

• To investigate the 3-dimensional geometric remodeling patterns in severe AS.
• To compare AS remodeling with systemic hypertension (HTN) and healthy controls.
• To evaluate changes in AS remodeling post-aortic valve replacement (AVR).

Main Methods:

• Utilized cine cardiac magnetic resonance (CMR) in 91 subjects (36 AS, 19 HTN, 36 controls).
• Performed principal component analysis on 3D meshes from CMR scans to identify geometric signatures.
• Compared conventional metrics of shape, strain, and scar across groups.

Main Results:

• Identified a unique AS remodeling signature: increased wall thickness, LV left-right axis shift, and decreased short-axis eccentricity.
• Systemic hypertension (HTN) showed increased septal thickness.
• The combined signature effectively differentiated AS from HTN (AUC=0.792).
• LV left-right axis shift was irreversible post-AVR and predicted LV mass regression (R²=0.339).

Conclusions:

• Distinct LV remodeling signatures can differentiate the etiology of LV hypertrophy.
• LV axis shift is a characteristic, irreversible feature of AS remodeling.
• This axis shift may represent an adaptive mechanism and predicts postoperative LV mass regression.