MRI assessment of LV relaxation by untwisting rate: a new isovolumic phase measure of τ

2001 ◽  
Vol 281 (5) ◽  
pp. H2002-H2009 ◽  
Author(s):  
Sheng-Jing Dong ◽  
Paul S. Hees ◽  
Cynthia O. Siu ◽  
James L. Weiss ◽  
Edward P. Shapiro
Keyword(s):  
Diastolic Function ◽  
Left Atrial ◽  
Independent Predictor ◽  
Aortic Pressure ◽  
Left Ventricular ◽  
Resonance Imaging ◽  
Relaxation Time Constant ◽  
Tagged Magnetic Resonance Imaging ◽  
Independent Assessment ◽  
Isovolumic Relaxation

Most noninvasive measures of diastolic function are made during left ventricular (LV) filling and are therefore subject to “pseudonormalization,” because variation in left atrial (LA) pressure may confound the estimation of relaxation rate. Counterclockwise twist of the LV develops during ejection, but untwisting occurs rapidly during isovolumic relaxation, before mitral opening. We hypothesized that the rate of untwisting might reflect the process of relaxation independent of LA pressure. Recoil rate (RR), the velocity of LV untwisting, was measured by tagged magnetic resonance imaging and regressed against the relaxation time constant (τ), recorded by catheterization, in 10 dogs at baseline and after dobutamine, saline, esmolol, and methoxamine treatment. RR correlated closely (average r = −0.86) with τ and was unaffected by elevated LA pressure. Multiple regression showed that τ, but not LA or aortic pressure, was an independent predictor of RR ( P < 0.0001, P = 0.99, and P = 0.18, respectively). The rate of recoil of torsion, determined wholly noninvasively, provides an isovolumic phase, preload-independent assessment of LV relaxation. Use of this novel parameter should allow the detailed study of diastolic function in states known to affect filling rates, such as aging, hypertension, and congestive heart failure.

P613Cardiac magnetic resonance imaging derived left ventricular mechanical function in patients with atrial fibrillation and left atrial low voltage zones

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
S Ulbrich ◽  
R S Schoenbauer ◽  
B Kirstein ◽  
J Tomala ◽  
Y Huo ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Atrial Fibrillation ◽  
Magnetic Resonance ◽  
Stroke Volume ◽  
Left Atrial ◽  
Low Voltage ◽  
Left Ventricular ◽  
Left Ventricular Stroke Volume ◽  
Resonance Imaging ◽  
Ventricular Filling

Abstract Background The relation of left atrial low voltage zones (LVZ) to left ventricular function in patients undergoing pulmonary vein isolation (PVI) is not known. Objective To explore the relationship of left atrial low voltage zones (LVZ) on left ventricular function in patients with atrial fibrillation. Methods From June to Nov. 2018, 107 (mean age 67y, 70 men, 73 persistent AF) consecutive patients with symptomatic AF underwent a PVI with LVZ mapping. Before PVI the left ventricular ejection fraction (EF) and stroke volume (SV) were measured by cardiac magnetic resonance imaging (CMR). From feature-tracking of CMR-cine images left ventricular global, systolic and diastolic longitudinal strains (GLS), circumferential strains (GCS) and radial strains (GRS) were calculated. Results Of 59 patients CMR scanning in sinus rhythm was performed, LVZ were present in 24 patients. LVEF was significantly lower in patients with left atrial LVZ (62±9% vs. 55±15%) (p=0,03). Left ventricular stroke volume was significantly decreased by the extent of LVZ (94±23 vs. 72±21ml), (p=0,03). The left ventricular diastolic strains during ventricular filling (caused by atrial contraction) of GLS (r=−0,52), GCS (r=−0,65) and GRS (r=−0,65) were highly signifcantly correlated to the occurence and extent of LVZ (each p<0,001 respectively). The only systolic ventricular strain was GLS, which decreased (r=−0,3, p=0,03) by the occurance of atrial low voltage. Conclusion The active, atrial part of diastolic left ventricular filling properties is impaired by the occurrence and extent of left atrial LVZ. In patients with left atrial LVZ the left ventricular stroke volume and ejection fraction is decreased already in sinus rhythm. It seems possible that atrial mechanical dysfunction and presence of atrial low voltage maybe predicted by LV diastolic strain analysis.

Abstract 649: Increased Left Ventricular Filling Pressure is Associated with Left Atrial Thrombus in Patients with Atrial Fibrillation.

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Katsuomi Iwakura ◽  
Hiroshi Ito ◽  
Atsunori Okamura ◽  
Yasushi Koyama ◽  
Motoo Date ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Diastolic Function ◽  
Left Atrial ◽  
Multivariate Logistic Regression Analysis ◽  
Left Ventricular ◽  
Filling Pressure ◽  
Diastolic Filling ◽  
Ventricular Filling Pressure ◽  
Lv Diastolic Dysfunction ◽  
Ventricular Filling

Patients with atrial fibrillation (AF) are frequently associated with reduced left ventricular (LV) diastolic dysfunction. It is still unclear whether reduced diastolic function is associated with the risk of left atrial (LA) thrombus in AF. The ratio of transmitral E velocity to mitral annular velocity (e′) is an echocardiographic estimate of diastolic LV filling pressure even under AF rhythm. We investigated whether reduced LV diastolic function is associated with the risk of LA thrombus in AF patients, using E/e′ ratio as an index. We enrolled consecutive 405 patients with non-valvular, paroxysmal or chronic AF, who underwent both transthoracic- (TTE) and transesophagial echocardiography (TEE) examination within a month. We measured LA and LV dimensions, LV ejection fraction (%EF), wall thickness, E and e′ velocities on TTE, and determined E/e′ ratio. LA appendage thrombus was found in 33 patients (8.1%). Patients with LA thrombus showed lower e′ velocity (5.3±1.8 vs. 7.0±2.2 cm/s, p<.0001) and higher E/e′ ratio (17.2±9.2 vs. 11.5±5.9, p<.0001) than those without it. Using 12.4 as an optimal cutoff point, E/e′ predicted LA thrombus with 70% sensitivity and 70% specificity (AUC=0.72). Odds ratio for LA thrombus in patients in the highest quartile of E/e′ was 6.38 (3.06–13.9). Multivariate logistic regression analysis indicated that the highest quartiles of E/e′ ratio was an independent predictor of LA thrombus among echocardiographic parameters, along with LA dimension and %EF, whereas e′ was not. LA appendage flow velocity was significantly correlated with E/e′ ratio (p<.0001), implying that increased diastolic filling pressure could be associated with impaired blood flow within LA. Increased LV filling pressure increased the risk of LA thrombus in patients with AF, partially through impaired LA hemodynamics. E/e′ ratio on TTE could be useful for detecting high-risk patients for LA thrombus.

scholarly journals P934 Left atrial strain association with left ventricular diastolic function

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
I Rodriguez Sanchez ◽  
A Anton ◽  
J J Onaindia ◽  
S Velasco ◽  
J Florido ◽  
...  
Keyword(s):  
Ejection Fraction ◽  
Diastolic Function ◽  
Left Atrial ◽  
Normal Function ◽  
Left Ventricular ◽  
P Value ◽  
Peak Strain ◽  
Progressive Decrease ◽  
Significant Group ◽  
Global Peak

Abstract Objectives to evaluate the relationship between left atrial (LA) peak strain and left ventricular (LV) diastolic function and determine whether LA strain could be used to detect elevated filling pressures in a population of patients with preserved LV ejection fraction (LVpEF). Background the assessment of diastolic function is complex and multiparameter. 2016 ASE and EACVI algorithm has simplified this approach, but there are still patients with discrepant values leading to an indeterminate diagnosis, specially in patients with preserved ejection fraction. Methods we prospectively included 129 patients in our cohort. Inclusion criteria were LVEF &gt; 50% and sinus rhythm. Patients with atrial fibrillation, significant mitral valvulopathy or poor quality imaging were excluded. Two-dimensional speckle tracking was used to measure peak LA strain in all LA segments (using apical 4 chamber, 2 chamber and 3 chamber views). We evaluated the association of LA global peak strain and LA 4 chamber peak strain with the different categories of diastolic function according to the 2016 ASE and EACVI algorithm. Results Both LA global peak strain and 4 chamber LA peak strain showed a progressive decrease with worsening diastolic dysfunction (DD) severity (Table 1). A global LA peak strain cutoff value of 28,35% was very accurate to differentiate normal from elevated filling pressures (normal function or grade 1 DD from grades 2 and 3 DD). Diagnostic accuracy: 80.20%; area under the curve: 0,80 (0,72-0,88); A significant group of patients (21,1%) could not be categorized using 2016 algorithm. Conclusions Both LA global peak strain and 4 chamber LA peak strain demonstrated a progressive decrease with worsening DD severity. Global LA peak strain value of 28,35% was an accurate cutoff to differenciate patients with normal vs elevated filling pressures. LA strain values and diastolic function Total LA global peak STRAIN LA 4C STRAIN N (%) p-value p-value Total 129 30.90 %(11.77) 30.43 (12.36) Diastole &lt;0.0001 &lt;0.0001 Normal function 36 (28.13) 39.72% (9.59) 39.98 (10.59) Indeterminate Diastolic Function 23 (17.97) 31.07% (7.97) 30.19 (7.50) Indeterminate DD 4 (3.13) 30.68 % (6.72) 29.75 (7.31) grade 1 DD 22 (17.19) 32.69 % (12.54) 32.98 (14.46) grade 2 DD 36 (28.13) 23.90 % (9.32) 23.53 (9.49) grade 3 DD 7 (5.47) 15.43 % (5.72) 15.85 (7.32)

scholarly journals Genetic inhibition of calcineurin induces diastolic dysfunction in mice with chronic pressure overload

2009 ◽  
Vol 297 (5) ◽  
pp. H1814-H1819 ◽  
Author(s):  
Ricardo J. Gelpi ◽  
Shumin Gao ◽  
Peiyong Zhai ◽  
Lin Yan ◽  
Chull Hong ◽  
...  
Keyword(s):  
Diastolic Dysfunction ◽  
Diastolic Function ◽  
Systolic Function ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Aortic Banding ◽  
Lv Systolic Function ◽  
Calcineurin Inhibition ◽  
Lv Diastolic Function ◽  
Isovolumic Relaxation

Calcineurin is a Ca2+/calmodulin-dependent protein phosphatase that induces myocardial growth in response to several physiological and pathological stimuli. Calcineurin inhibition, induced either via cyclosporine or genetically, can decrease myocardial hypertrophy secondary to pressure overload without affecting left ventricular (LV) systolic function. Since hypertrophy can also affect LV diastolic function, the goal of this study was to examine the effects of chronic pressure overload (2 wk aortic banding) in transgenic (Tg) mice overexpressing Zaki-4β (TgZ), a specific endogenous inhibitor of calcineurin, on LV diastolic function. As expected, in the TgZ mice with calcineurin inhibitor overexpression, aortic banding reduced the degree of LV hypertrophy, as assessed by LV weight-to-body weight ratio (3.5 ± 0.1) compared with that in non-Tg mice (4.6 ± 0.2). LV systolic function remained compensated in both groups with pressure overload. However, the LV end-diastolic stress-to-LV end-diastolic dimension ratio, an index of diastolic stiffness and LV pressure half-time and isovolumic relaxation time, two indexes of isovolumic relaxation, increased significantly more in TgZ mice with aortic banding. Protein levels of phosphorylated phospholamban (PS16), sarco(endo)plasmic reticulum Ca2+-ATPase 2a, phosphorylated ryanodine receptor, and the Na+/Ca2+ exchanger were also reduced significantly ( P < 0.05) in the banded TgZ mice. As expected, genetic calcineurin inhibition inhibited the development of LV hypertrophy with chronic pressure overload but also induced LV diastolic dysfunction, as reflected by both impaired isovolumic relaxation and increased myocardial stiffness. Thus genetic calcineurin inhibition reveals a new mechanism regulating LV diastolic function.

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