Postoperative Reverse Remodeling and Symptomatic Improvement in Normal-Flow Low-Gradient Aortic Stenosis After Aortic...

Area of Science:

• Cardiology
• Cardiac Surgery
• Cardiovascular Imaging

Background:

• Severe aortic stenosis (AS) presents with reduced aortic valve area and normal stroke volume index.
• Normal-flow low-gradient (NFLG) AS poses a controversial indication for aortic valve replacement (AVR).
• Preoperative and postoperative left ventricular (LV) remodeling and symptomatic benefit in NFLG AS remain unclear.

Purpose of the Study:

• To compare preoperative and postoperative LV remodeling and myocardial fibrosis in patients with NFLG AS versus normal-flow high-gradient AS.
• To assess the symptomatic benefit of AVR in NFLG AS patients.
• To identify predictors of reverse remodeling after AVR.

Main Methods:

• Eighty-seven patients with severe AS and normal stroke volume index undergoing AVR were analyzed.
• Echocardiography, cardiac MRI, 6-minute walk test, and natriuretic peptide levels were measured pre- and post-AVR.
• Patients were stratified into NFLG and normal-flow high-gradient groups.

Main Results:

• 38% of patients had NFLG AS.
• NFLG patients had less severe AS (larger aortic valve area index) and lower LV mass index pre-AVR.
• Post-AVR, NFLG patients showed smaller reductions in LV mass index and natriuretic peptides, but similar symptomatic improvement compared to normal-flow high-gradient patients.
• Normal-flow high-gradient status independently predicted LV mass index changes.

Conclusions:

• NFLG AS is associated with less severe AS and LV remodeling compared to normal-flow high-gradient AS.
• NFLG patients exhibit reduced reverse remodeling post-AVR but achieve comparable symptomatic relief.
• These findings suggest differential management strategies may be warranted for NFLG AS.