736 Mechanism behind pre- and postejection velocity spikes in normal left ventricular myocardium
| Autor: | T. Vartdal, A. Opdahl, E. Pettersen, T. Edvardsen, O.A. Smiseth, E. Lyseggen, Espen W. Remme, T. Helle-Valle |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Aortic valve
medicine.medical_specialty Cardiac cycle business.industry Speckle tracking echocardiography General Medicine Sonomicrometry medicine.anatomical_structure Internal medicine Mitral valve medicine Left ventricular myocardium Cardiology Radiology Nuclear Medicine and imaging Wall motion Systole Cardiology and Cardiovascular Medicine business |
| Zdroj: | European Journal of Echocardiography. 7:S123-S123 |
| ISSN: | 1525-2167 |
| DOI: | 10.1016/s1525-2167(06)60459-9 |
| Popis: | s S123 Eur J Echocardiography Abstracts Supplement, December 2006 736 Mechanism behind preand postejection velocity spikes in normal left ventricular myocardium E.W. Remme 1 ; O.A. Smiseth 1 ; T. Helle-Valle 1 ; A. Opdahl 1 ; E. Pettersen 1 ; T. Vartdal 1 ; T. Edvardsen 1 ; E. Lyseggen 1 1Rikshospitalet-Radiumhospitalet Medical Center, Cardiology (Ifkf) Dept., Oslo, Norway Background: The velocity trace of normal left ventricular (LV) wall motion has distinct waves corresponding to the different phases of the cardiac cycle. However, there are two unexplained velocity spikes in the trace one just before and one just after the ejection wave. We hypothesize that the preand postejection velocity spikes are due to early-systolic shortening and late-systolic lengthening that is interrupted by mitral (MVC) and aortic valve closure (AVC), respectively. Methods and results: LV longand short-axis diameters were measured by sonomicrometry in 11 anesthetised dogs. Myocardial shortening started prior to MVC (21±10 ms). There was excellent agreement between MVC and interruption of the initial shortening during early systole (4±7 ms) where the interruption was defined as peak deceleration of shortening. Onset of lengthening preceded AVC by (31±15 ms). Interruption of the late systolic lengthening, defined as peak deceleration of lengthening, corresponded (0±3 ms) to AVC. We further investigated if abolishing aortic and mitral valve closure by stenting the valves would eliminate the preand postejection velocity spikes in separate experiments. Stenting of the mitral valve essentially abolished the preejection velocity spike, and stenting the aortic valve essentially abolished the postejection velocity spike. In a group of 10 healthy individuals LV longitudinal and radial shortening were measured by speckle tracking echocardiography. Peak deceleration of the early systolic shortening coincided (2±14 ms) with MVC, while peak deceleration of late systolic lengthening coincided (5±12 ms) with AVC. Conclusion: This study support the hypothesis that the normal LV preand postejection velocity spikes are attributed to mitral and aortic valve closure that temporarily interrupt early systolic shortening and late systolic lengthening, respectively. |
| Databáze: | OpenAIRE |
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