CONTACTLESS measurement of left ventricular ejection time (LVET) demonstrates comparable accuracy to echocardiography (ECG), while enabling automated cardiovascular assessment, according to new research.
LVET, a key marker of systolic cardiac function, is typically measured using ECG technology, which may become limited based on operator availability in time-strapped clinical settings. This new study introduces a contactless method of measuring LVET using a laser Doppler vibrometer (LDV) directed at the jugular notch.
Comparable Results Observed in LDV and ECG
A cohort of 238 participants underwent both LDV and ECG assessments. The researchers observed that participant LVET values obtained through LDV were statistically equivalent to reference ECG measurements (±25 milliseconds).
The mean values of both assessments were closely aligned: 304 ms (±21) using the LDV method compared to 309 ms (±25) for ECG, with a mean difference of -4.75 ms (±19) and percentage error of 4.93%.
These findings suggest that contactless LDV measurement of LVET can provide clinically reliable cardiovascular data without the need for specialised equipment operators or physical sensors.
Automated Analysis Enables Scalable Cardiovascular Screening
The researchers developed a deep learning model to automate extraction of the LVET from jugular notch signals. The model achieved a mean absolute error of 8.08 ms, demonstrating consistent perform across patient subgroups.
By combining rapid LVET extraction and automated analysis, the researchers propose that contactless LDV measurement may become a feasible tool for high-throughput cardiovascular screening and triage in clinical practice.
Detecting Differences in Valvular Pathology
Exploratory analysis further supported the clinical utility of the approach. The LVET index derived from contactless LDV measurements was significantly prolonged in patients with aortic stenosis and aortic insufficiency compared with low-risk control patients.
These findings demonstrate that contactless LDV measurement of LVET can also detect clinically meaningful differences associated with valvular pathology, reinforcing its potential as a cardiovascular screening and triage tool.
While further validation is required, these advances represent a significant step toward integrating contactless cardiovascular monitoring into routine clinical screening. Future research may also help determine whether contactless LDV can be extended to measure additional cardiac parameters beyond LVET.
Reference
Gonzalez-Billandon J et al. Automated measurement of left ventricular ejection time via contactless suprasternal notch laser vibrometry. Sci Rep. 2026; DOI: 10.1038/s41598-026-51677-7
Featured image: Chaikom on Adobe Stock
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