Surrogate Estimation of Left Ventricular Ejection Fraction from Carotid Artery Wall Dynamics

The accurate assessment of left ventricular ejection fraction (LVEF) is essential for evaluating cardiac function, particularly in clinical settings where traditional imaging methods may have limitations. This feasibility study explores the potential of carotid diameter and carotid flow velocity waveform analysis as a surrogate for LVEF assessment. Carotid artery dimensions and flow velocity were recorded using ultrasound Duplex mode to capture diameter and velocity waveforms. Key parameters such as end-diastolic diameter, peak systolic diameter, systolic duration, diastolic duration, peak systolic velocity, and end-diastolic velocity were extracted for analysis. The study included 26 participants (16 males and 10 females), and carotid-derived LVEF surrogates were compared with LVEF measurements obtained via echocardiography using the E-Point Septal Separation (EPSS) method. Linear regression analysis revealed a strong correlation between carotid-derived LVEF surrogate and echocardiography-based LVEF (R = 0.78), which was significantly improved (R = 0.85) after incorporating carotid stiffness index β, resulting in reduced bias. This study demonstrates the feasibility of carotid diameter and flow velocity waveform analysis as a promising non-invasive tool for surrogate estimation of LVEF. The inclusion of β enhances the correlation, highlighting its potential as a reliable method for assessing ventricular ejection fraction in clinical settings. Further research is necessary to validate this approach across diverse populations.