Ultra-high frame rate ultrasound reveals scar after myocardial infarcation

In his PhD thesis, Lars Christian Naterstad Lervik has shown that ultra-high frame rate tissue Doppler imaging is feasible and clinically useful.


MAIN RESULTS:

  1. Ultra-high-frame-rate tissue Doppler imaging provides additional information to conventional tissue Doppler imaging in early and late systole.
  2. Ultra-high frame rate imaging identifies scarred myocardium and differentiated transmural from non-transmural distribution of myocardial scar on a segmental level.
  3. Analysis of strain rate by data from ultra-high frame rate tissue Doppler imaging is feasible in a larger number of segments compared with strain rate by conventional tissue Doppler imaging.

THESIS DEFENCE:

Thesis: Ultra-high frame rate tissue Doppler imaging, technical feasibility and first clinical experiences
Candidate: Lars Christian Naterstad Lervik
Time: November 23, 2017 at 12:15
Place: Medical Technical Research Centre, St. Olavs Hospital: Auditorium MTA
Link to university website (in Norwegian)


SUMMARY:

(1) Lervik and co-workers describe a new tissue Doppler imaging method with a frame rate of 1200 frames per second in a four-chamber apical view. Feasibility of the new method was confirmed in ten healthy volunteers, as peak annular velocities and time to peak S′ intervals were in good agreement with measurements from conventional tissue Doppler imaging. The ultra-high frame rate method also provided additional information in early and late systole, as it was able to separate the timing of electrical activation, start of mechanical contraction, mitral valve closure and start of ejection.

(2) Retrospective spectral Doppler from ultra-high frame rate imaging enables assessment of strain rate without the influence of clutter seen by convensional tissue Doppler imaging. In 20 patients with a recent myocardial infarction the new method was the only one that differentiated transmural from non-transmural distribution of myocardial scar on a segmental level. The method also had several other advantages compared to the conventional method.


REFERENCES:

Brekke, B., Nilsen, L. C., Lund, J., Torp, H., Bjastad, T., Amundsen, B. H., Støylen, A., & Aase, S. A. (2014). Ultra-high frame rate tissue Doppler imagingUltrasound in medicine & biology40(1), 222-231.

Lervik, L. C. N., Brekke, B., Aase, S. A., Lønnebakken, M. T., Stensvåg, D., Amundsen, B. H., Torp, H., & Støylen, A. (2017). Myocardial Strain Rate by Anatomic Doppler Spectrum: First Clinical Experience Using Retrospective Spectral Tissue Doppler from ULTRA-HIGH FRAME RATE IMAGINGUltrasound in Medicine & Biology