Differential left ventricular remodelling and longitudinal function distinguishes low flow from normal-flow preserved...

Area of Science:

• Cardiology
• Echocardiography
• Clinical Medicine

Background:

• Identifying severe aortic stenosis (AS) with preserved left ventricular ejection fraction, low flow, and low gradients (LFLG) is challenging.
• Previous studies conflict on whether LFLG AS patients have significant concentric remodeling and decreased survival or features similar to moderate AS.

Purpose of the Study:

• To compare clinical characteristics, echocardiographic features, and survival in LFLG AS patients versus normal-flow, low-gradient (NFLG) severe AS and moderate AS.
• To identify predictors of survival in LFLG AS patients.

Main Methods:

• Retrospective comparison of LFLG AS (n=38), NFLG severe AS (n=75), and moderate AS (n=70) cohorts.
• Analysis of clinical data, echocardiographic parameters (end-diastolic volume index, relative wall thickness (RWT), septal mitral annular displacement), and New York Heart Association (NYHA) functional class.
• Cox proportional hazards analysis for survival predictors.

Main Results:

• LFLG AS patients exhibited lower end-diastolic volume index, higher RWT, and reduced septal mitral annular displacement compared to NFLG and moderate AS groups.
• NYHA class III/IV symptoms were most frequent in the LFLG group.
• Three-year survival was significantly lower in LFLG AS compared to NFLG and moderate AS, with no difference between NFLG and moderate AS.

Conclusions:

• Patients with preserved ejection fraction LFLG AS demonstrate significant concentric remodeling and impaired longitudinal function, predicting poor long-term survival.
• Higher NYHA class, increased RWT, and reduced septal displacement independently predicted survival in LFLG AS.
• Normal-flow, low-gradient AS patients have outcomes comparable to moderate AS.