Non-invasive pressure-volume analysis: a novel method for evaluating ventricular function in patients with aortic...

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Imaging

Background:

• Conventional echocardiography (ejection fraction, global longitudinal strain) lacks comprehensive assessment of left ventricular (LV) function under varying loading conditions.
• Pressure-volume (PV) analysis offers detailed cardiac function and energetics but requires invasive measurements, limiting clinical use.
• Development of a clinically accessible, non-invasive PV loop analysis method is needed.

Purpose of the Study:

• To develop and validate a non-invasive method for pressure-volume loop analysis.
• To assess changes in myocardial function and energetics using this novel non-invasive technique.
• To compare the diagnostic capabilities of non-invasive PV analysis with conventional echocardiography.

Main Methods:

• Simultaneous 3D echocardiography and invasive LV pressures were acquired during transcatheter aortic valve replacement (TAVR).
• Echocardiogram-derived volume-time traces were combined with invasive and non-invasively estimated LV pressures to construct PV loops.
• PV loops were analyzed pre- and post-TAVR to evaluate myocardial function and energetics.

Main Results:

• Non-invasive LV pressure estimations showed high correlation with invasive measurements for stroke work (r=0.95, ICC=0.95).
• Post-TAVR, significant improvements were observed in ventricular efficiency and ventriculo-arterial coupling, with decreased energy consumption.
• Conventional echocardiographic parameters (LV EF, GLS) showed no significant changes post-TAVR, unlike PV analysis findings.

Conclusions:

• Non-invasive PV loop analysis is validated and clinically accessible for patients with aortic stenosis.
• This method detects changes in myocardial energetics and ventriculo-arterial interaction missed by conventional echocardiography.
• Non-invasive PV analysis holds significant potential for both clinical practice and research in cardiology.