Related Experiment Video
Updated: Sep 10, 2026
Transthoracic Speckle Tracking Echocardiography for the Quantitative Assessment of Left Ventricular Myocardial Deformation
Published on: October 20, 2016
Ventricular-arterial coupling during exercise and tilt assessed using a pulse wave velocity-to-global longitudinal
Skye H T Ling1, Lea Nguyen1, Jessica N Jasiak1
1Department of Kinesiology and Health Sciences, University of Waterloo, Waterloo, Ontario, Canada.
Abstract:
Ventricular-arterial coupling (VAC) is commonly assessed using the echocardiography-derived ratio of arterial elastance to end-systolic elastance (Ea/Ees), a convenient but global construct that collapses ventricular and arterial properties into a single lumped parameter. A proposed index, combining pulse wave velocity and global longitudinal strain (PWV/GLS), provides a mechanistically-grounded representation of coupling by directly integrating measures of arterial stiffness and myocardial deformation. This study compared the ability of Ea/Ees and PWV/GLS to discriminate between acute physiological stress conditions. Twenty healthy young adults (10 females; 23±2 years) completed a randomized crossover graded cycling protocol (25W, 75W, and fixed heart rate ~130 bpm) in supine and 20° head-up tilt (HUT). HUT induced changes in ventricular volume loading, thereby challenging inherent assumptions underlying Ea/Ees. Ea/Ees progressively declined with increasing exercise intensity (main effect of stage p<0.01; all p<0.05 from previous stage), reflecting increased left ventricular elastance (Ees) relative to arterial load (Ea). Ea/Ees showed no detectable differences between supine and HUT either at rest or at any exercise stage (interaction p > 0.05). In contrast, PWV/GLS was less sensitive to exercise intensity (all stages only different from baseline p < 0.05) but showed a difference from supine to HUT at rest (p < 0.01). These findings support a context-dependent approach to VAC assessment: Ea/Ees reflects volumetric-pressure coupling during exercise, whereas PWV/GLS was responsive to fluid shifts and preload changes, supporting its potential as an alternative VAC measure that captures arterial wave propagation and myocardial deformation when the assumption of a negligible V0 is challenged.
Related Concept Videos
01:25Assessment of apical radial pulse
The A-R pulse assessment involves simultaneous evaluation of the apical and radial pulses. When the apical and radial pulse rates vary, this assessment helps identify a pulse deficit.
Pre-Procedural Preparation
01:19Assessing Blood pressure using a doppler ultrasound
Pre-Procedural Guidelines for Doppler Ultrasound Blood Pressure Assessment:
Preparation of Equipment:
01:25Assessment of the Cardiovascular System IV: Auscultation
Normal Heart Sounds
S1 (First Heart Sound)-
S1 is made by the closure of the mitral and tricuspid valves (atrioventricular valves), marking the beginning of systole.
S2 (Second Heart Sound)-
S2 is made by the closure of the aortic and pulmonic valves (semilunar valves), marking the end of the systole.
01:17Assessment of apical pulse
Assessing the apical pulse is a critical nursing procedure, particularly indicated for:
01:11Assessment of radial pulse
The radial pulse, located at the wrist, is often the preferred site for assessing peripheral pulse because of its accessibility and dependability. The process of determining the radial pulse involves several steps:
01:25Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...