#Cardiosky #Echosky Basal shortening during IVR isn't "wasted work", the simultaneous stretching the apical part sets up a pressure gradient/volume displacement, creating an apical momentum facilitating flow during early filling
🇳🇴Asbjørn Støylen🇩🇰
@strain-rate.bsky.social
Professor emeritus of cardiovascular physiology at NTNU, Trondheim. Academic tweets now on bluesky. Myocardial imaging / mechanics. #EchoSky #CardioSky #MedSky https://folk.ntnu.no/stoylen/strainrate/ Other interests: #Birds Nature, environment, history
#Cardiosky #Echosky Do strain - pressure loops measure myocardial stroke work? No. SW = mean ventricular SBP - mean ventricular DBP x SV. GLS do not correlate with SV across a normal population. Why? SV increases with body (and heart) size. GLS decreases with body (and heart) size.
LA reservoir strain (LARS) is NOT a measure of atrial compliance (distensibility) as atrial distension is due to LV contraction, not pressure, hence the proxy for LA pressure / LARS is NOT a measure of LA stiffness.
#Cardiosky #Echosky The north wind is just as cold blowing from the front or the back. AV-plane motion does not change interpretation when seen from the atrium or the ventricle. And what is the physiological meaning of MAPSE relative to atrial size??? On LA strain during ventricular systole.
#Cardiosky Atrial contraction strain. Numerator is AV-plane motion during atrial systole, expressing volume injected into the ventricle (i.e. the A wave). Denominator is atrial length, but as volume is partly a function of ventricular EDP, ventricular compliance is a confounder.
2024 was a blast in cardiovascular imaging congresses led by EACVI. Be ready for #EACVI2025: 📍Vienna 📅11-13 Dcember 👨👩👦👦#EuroeEcho, #EuroCMR and #ICNC-CT together Help us to shape the programme and be part of it 👉https://escardio.formstack.com/forms/eacvi_2025_call_for_sessions #cardiosky
#Cardiosky Contractility cannot be measured by cardial imaging; all imaging measures shortening (=volume reduction), which is load dependent. Myocardial contraction is not shortening, during systole there is both contraction without shortening, and shortening without contraction.
#Cardiosky Regional strain pressure loops. Do they add information to regional strain? (Spoiler alert: they don't)
#Cardiosky. Being both pre-and afterload dependent, myocardial stroke work is not a contractility measure. As GLS do not correlate with SV, Strain pressure loops do not measure stroke work.
#Cardiosky 1: “Longitudinal strain” is not the real longitudinal shortening, as it adds the effect of inward tracking. 2: The inward gradient of longitudinal strain is an artefact of feature tracking.
US anti-vax stance to blame for continent-wide surge in measles, say experts
#Cardiosky. Blood speckle tracking. No longer only visualisation. Validation of quantitative intraventricular pressure gradient measurement. Congratulation. academic.oup.com/ehjcimaging/...
Intraventricular pressure difference estimation based on blood speckle tracking—invasive validation and early clinical application
AbstractAims. Ventricular relaxation creates an intraventricular pressure difference (IVPD) and resultant diastolic suction. Non-invasive estimation by ech
academic.oup.com
#Cardiosky Attempt to estimate LA pressure from echo. The formula uses among other measures tau, non invasive estimated from among other IVRT. But IVRT depends both on tau and LAP. How is that for circular reasoning? doi.org/10.1093/ehjc...
Imaging-based method to quantify left ventricular diastolic pressures
AbstractAims. To establish an imaging-based method to quantify left ventricular (LV) diastolic pressures.Methods and results. In 115 patients suspected of
doi.org
#Cardiosky Regional strain pressure loops. Do they add information to regional strain? (Spoiler alert: they don't)
#Cardiosky Contractility cannot be measured by cardial imaging; all imaging measures shortening (=volume reduction), which is load dependent. Myocardial contraction is not shortening, during systole there is both contraction without shortening, and shortening without contraction.
#Cardiosky. Being both pre-and afterload dependent, myocardial stroke work is not a contractility measure. As GLS do not correlate with SV, Strain pressure loops do not measure stroke work.
#Cardiosky When has normal EF been equivalent to normal LV function?!??
American Society of Echocardiography@ase360.bsky.social · last yr.Heart failure with preserved ejection fraction is a heterogeneous entity including different phenotypes of near normal, normal, and supernormal left ventricular function. The aim of this study was to assess the value of resting LV elastance using TTE to identify HFpEF phenotypes. bit.ly/4kLUJc4
#Cardiosky Atrial contraction strain. Numerator is AV-plane motion during atrial systole, expressing volume injected into the ventricle (i.e. the A wave). Denominator is atrial length, but as volume is partly a function of ventricular EDP, ventricular compliance is a confounder.
#Cardiosky Atria fills during ventricular ejection and early ventricular diastole. In ventr. ejection, atria expand by apical AV-plane motion driven by ventricular shortening. In early diastole, atria fill by ventricular transverse recoil/expansion, as the atria are compressed longitudinally.
#Cardiosky #Echosky The north wind is just as cold blowing from the front or the back. AV-plane motion does not change interpretation when seen from the atrium or the ventricle. And what is the physiological meaning of MAPSE relative to atrial size??? On LA strain during ventricular systole.
#Cardiosky #Echosky Atrial filling and emptying is related to ventricular systolic and diastolic ventricular function, as volume changes are mainly a function of AV-plane motion within a relatively unchanged outer heart contour
#Cardiosky #Echosky I have collected some recent posters from Bluesky / Twitter and some diagrams from the strain rate website in a compendium on Left ventricular mechanics. It can bee downloaded (free) as *.pdf. from the strain rate front page. stoylen.folk.ntnu.no/strainrate/
Animations will still be in *.GIF format, so they will run on web browsers, and can be embedded in presentations. Pictures and animations are still free to use, with due credit. Strain and strain rate are the concepts of myocardial deformation. My basic views are still that
stoylen.folk.ntnu.no
#Cardiosky #Echosky LV ejection is a complex interaction between LV contraction - relaxation, flow acceleration - deceleration and artery - ventricular coupling.
#Cardiosky #Echosky Pre ejection velocity -occurs before MVC, and is not isovolumic. -is true ventricular contraction, not atrial recoil -is the true LV electromechanical activation timepoint. -peak pre ejection velocity or acceleration is not an LV contractility measure
