Mechanical Wave Analysis at High Frame-Rate Echocardiography: Feasibility, Determinants, and Normal Ranges

Area of Science:

• Cardiovascular Imaging
• Biomedical Engineering
• Physiology

Background:

• High-frame-rate echocardiography detects mechanical waves (MW), offering potential to assess tissue properties.
• Current clinical application is limited by potential overlap between normal MW ranges and pathological conditions like LV dysfunction.

Purpose of the Study:

• To determine the feasibility, normal ranges, and determinants of MW velocities in healthy individuals and cardiac patients.
• To assess the clinical utility of MW measurements in diagnosing cardiac pathology.

Main Methods:

• Recruited asymptomatic participants and patients for high-frame-rate echocardiography.
• Acquired MW signals (atrial kick, aortic valve closure, mitral valve closure) from standard echocardiographic views.
• Utilized manual and automated methods for measurement, with outlier removal and classification into normal/abnormal groups.

Main Results:

• Manual MW measurement was feasible in 77-91% of cases, outperforming automated methods.
• MW velocities showed little correlation with hemodynamic or cardiac function markers.
• Atrial kick MW velocity was the only parameter significantly different between normal and abnormal echocardiogram groups.

Conclusions:

• Mechanical wave measurement, particularly atrial kick, is a feasible addition to echocardiography.
• Normal ranges for MW velocities are wide, limiting their diagnostic specificity.
• MW velocities do not appear significantly altered in cases of subclinical cardiac dysfunction.