Global diastolic strain rate for the assessment of left ventricular relaxation and filling pressures.
BACKGROUND
Diastolic strain rate (SR) measurements that comprise all left ventricular (LV) segments are advantageous over myocardial velocity for assessment of diastolic function. Mitral early diastolic velocity (E)/SR ratio during the isovolumetric relaxation (IVR) period can be used to estimate LV filling pressures.


RESULTS
Simultaneous echocardiographic imaging and LV pressure measurements (7F catheters) were performed in 7 adult dogs. Loading conditions were altered by saline infusion and caval occlusion, and lusitropic state was changed by dobutamine and esmolol infusion. A curve depicting global SR was derived from each of the 3 apical views, and SR was measured during IVR (SR(IVR)) and early LV filling (SR(E)). SR(IVR) had a strong correlation with time constant of LV pressure decay during the IVR period (tau) (r=-0.83, P<0.001), whereas SR(E) was significantly related to LV end-diastolic pressure (r=0.52, P=0.005) in the experimental stages where tau was <40 ms. In 50 patients with simultaneous right heart catheterization and echocardiographic imaging, mitral E/SR(IVR) ratio had the best correlation with mean wedge pressure (r=0.79, P<0.001), as well as in 24 prospective patients (r=0.84, P=0.001). E/SR(IVR) was most useful in patients with ratio of E to mitral annulus early diastolic velocity (E/Ea ratio) 8 to 15 and was more accurate than E/Ea in patients with normal ejection fraction and regional dysfunction (both P<0.01).


CONCLUSIONS
Global SR(IVR) by 2-dimensional speckle tracking is strongly dependent on LV relaxation. E/SR(IVR) can predict LV filling pressures with reasonable accuracy, particularly in patients with normal ejection fraction and in those with regional dysfunction.
Wang
Jianwen
J
Department of Cardiology and Methodist DeBakey Heart Center, The Methodist Hospital, Houston, Tex 77030, USA.
Khoury
Dirar S
DS
Thohan
Vinay
V
Torre-Amione
Guillermo
G
Nagueh
Sherif F
SF
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000328:Adult; D000368:Aged; D000617:Aminoglycosides; D000818:Animals; D006328:Cardiac Catheterization; D002316:Cardiotonic Agents / Q000494:pharmacology; D003971:Diastole / Q000187:drug effects / Q000502:physiology*; D004280:Dobutamine / Q000494:pharmacology; D004285:Dogs; D015150:Echocardiography, Doppler / Q000379:methods*; D053281:Enediynes; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000502:physiology; D008955:Models, Cardiovascular; D011237:Predictive Value of Tests; D011412:Propanolamines / Q000494:pharmacology; D011669:Pulmonary Wedge Pressure; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology*; D017725:Ventricular Pressure / Q000187:drug effects / Q000502:physiology*
D000319:Adrenergic beta-Antagonists; D000617:Aminoglycosides; D002316:Cardiotonic Agents; D053281:Enediynes; D011412:Propanolamines; D004280:Dobutamine; C036604:esmolol; C047543:esperamicin A1