scholarly journals High frame rate speckle tracking echocardiography to assess diastolic function

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
K Papangelopoulou ◽  
M Orlowska ◽  
S Bezy ◽  
A Petrescu ◽  
A Werner ◽  
...  
Keyword(s):  
Diastolic Function ◽  
Temporal Resolution ◽  
Speckle Tracking ◽  
Reference Method ◽  
Left Ventricular ◽  
Frame Rate ◽  
Doppler Imaging ◽  
Diastolic Filling ◽  
High Frame Rate ◽  
Custom Made

Abstract Background Left ventricular (LV) strain rate (SR) during isovolumic relaxation (SRIVR) and early diastolic filling (SRe) has previously been shown to correlate with the invasive gold standard for LV diastolic function (i.e. the time constant of LV pressure decay tau). However, the translation of these biomarkers to the clinic has been hampered by technical limitations. Indeed, conventional speckle tracking (STE) is limited by its temporal resolution, whereas tissue Doppler imaging (TDI) is angle-dependent, labor-intensive and thus rarely used clinically nowadays. Purpose The aim of this study was to show that these limitations could be overcome by using a recently proposed STE algorithm operating on high frame rate (HFR) imaging data. Methods 37 subjects (age: 64±12, 81% male) were included in the study; 16 had cardiac amyloidosis, 12 were undergoing clinically indicated left and/or right heart cardiac catheterization and 9 were healthy volunteers. Since the sequence of left ventricular activation and thus the repolarization process (i.e. relaxation) starts at mid septum, we measured SRIVR and SRe in the mid septal segment in an apical 4 chamber view using a commercially available clinical system with: (1) TDI (frame rate (FR) ∼142 Hz); (2) STE (FR ∼65 Hz). Moreover, subjects were scanned with HD-PULSE, an experimental high frame ultrasound scanner (FR ∼915 Hz) and then a manually placed contour was tracked during the cardiac cycle by a custom-made 2D HFR STE algorithm, to compute and extract SRIVR and SRe from the mid septum. Since TDI is considered the reference method to assess SR, conventional as well as HFR STE values were correlated against the TDI SR values. Results In 3 subjects, SRIVR could not be reliably assessed with the clinical STE approach, which we attributed to the relatively low temporal resolution of the images; all other measurements could be made in all subjects. For both biomarkers, HFR STE values correlated better with the TDI reference measurements than the clinical STE estimates (Fig.1). The latter estimates showed a systematic underestimation (bias −0.19 1/s (p<0.01) and −0.46 1/s (p<0.01) for SRIVR and SRe respectively) while no significant bias was observed for the HFR STE values. Similarly, the limits of agreement of the HFR STE values were narrower (−0.45 to +0.54 1/s and −0.94 to +0.86 1/s) than those of the clinical STE measurements (−0.85 to +0.48 1/s and −1.32 to +0.41 1/s). Conclusions These results show that HFR STE offers a reliable way to assess novel biomarkers of diastolic function in a user-friendly manner and can therefore facilitate their incorporation to the clinical practice. FUNDunding Acknowledgement Type of funding sources: None.

scholarly journals Speckle-Tracking Echocardiography With Novel High Frame-Rate Imaging

2021 ◽  
Author(s):  
Kana Fujikura ◽  
Mohammed Makkiya ◽  
Muhammad Farooq ◽  
Yun Xing ◽  
Wayne Humphrey ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Speckle Tracking ◽  
Speckle Tracking Echocardiography ◽  
Myocardial Strain ◽  
Left Ventricular ◽  
Frame Rate ◽  
High Frame Rate ◽  
Echocardiographic Images ◽  
The Impact ◽  
Normal Lvef

Background: global longitudinal strain (GLS) measures myocardial deformation and is a sensitive modality for detecting subclinical myocardial dysfunction and predicting cardiac outcomes. The accuracy of speckle-tracking echocardiography (STE) is dependent on temporal resolution. A novel software enables relatively high frame rate (Hi-FR) (~200 fps) echocardiographic images acquisition which empowers us to investigate the impact of Hi-FR imaging on GLS analysis. The goal of this pilot study was to demonstrate the feasibility of Hi-FR for STE. Methods: In this prospective study, we acquired echocardiographic images using clinical scanners on patients with normal left ventricular systolic function using Hi-FR and conventional frame rate (Reg-FR) (~50 FPS). GLS values were evaluated on apical 4-, 2- and 3-chamber images acquired in both Hi-FR and Reg-FR. Inter-observer and intra-observer variabilities were assessed in Hi-FR and Reg-FR. Results: There were 143 resting echocardiograms with normal LVEF included in this study. The frame rate of Hi-FR was 190 ± 25 and Reg-FR was 50 ± 3, and the heart rate was 71 ± 13. Strain values measured in Hi-FR were significantly higher than those measured in Reg-FR (all p < 0.001). Inter-observer and intra-observer correlations were strong in both Hi-FR and Reg-FR. Conclusions: We demonstrated that strain values were significantly higher using Hi-FR when compared with Reg-FR in patients with normal LVEF. It is plausible that higher temporal resolution enabled the measurement of myocardial strain at desired time point. The result of this study may inform clinical adoption of the novel technology. Further investigations are necessary to evaluate the value of Hi-FR to assess myocardial strain in stress echocardiography in the setting of tachycardia.

scholarly journals Shear wave elastography: can we discover elevated diastolic filling pressures?

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
AE Werner ◽  
S Bezy ◽  
M Orlowska ◽  
G Kubiak ◽  
J Duchenne ◽  
...  
Keyword(s):  
Diastolic Function ◽  
Shear Wave ◽  
Propagation Velocity ◽  
Shear Wave Elastography ◽  
Left Ventricular ◽  
Filling Pressure ◽  
Frame Rate ◽  
Diastolic Filling ◽  
High Frame Rate ◽  
Echocardiographic Parameters

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): University Hospitals (Uz) Leuven Background  The assessment of the left ventricular diastolic function is complex, as there is no single invasive parameter that provides a direct measurement of myocardial relaxation, myocardial compliance, or – as a surrogate - LV filling pressure. Estimation of diastolic function is therefore based on the combination of several parameters. Shear wave (SW) elastography is a novel method based on high frame rate echocardiography. SWs occur after mechanical excitation of the myocardium, e.g. after mitral valve closure (MVC), and their propagation velocity is directly related to myocardial stiffness (MS). Purpose The aim of this study was to investigate if velocities of natural shear waves are related to MS at end-diastole (ED) and, thus, could be used to estimate left ventricular end-diastolic pressures (LVEDP) as marker of diastolic function. Methods So far, we have prospectively enrolled 42 patients with a wide range of diastolic function, scheduled for heart catheterization so that LV filling pressures could be invasively measured. Patients with severe aortic stenosis, mitral stenosis of any degree and a more than moderate mitral regurgitation, as well as regional myocardial abnormalities or dysfunction in the anteroseptal wall were excluded. Echocardiography was performed immediately after catheterization. SW elastography in parasternal long axis views of the left ventricle (LV) was performed using an experimental scanner (HD-PULSE) at 1100 ± 250 frames per second. Tissue acceleration maps were extracted from an anatomical M-mode line along the midline of the LV septum. The SW propagation velocity at MVC was measured as the slope on the M-mode acceleration map (Figure A). Standard echocardiographic parameters of diastolic function were obtained with a high end ultrasound machine. Results SW velocities at ED correlated well with the invasively measured LVEDP (r = 0.74, p < 0.001, Figure B). In comparison, classical echocardiographic parameters correlated only weakly with LVEDP (E/A: r = 0.398, p = 0.02, Figure C; E/E’: r = 0.204, p = 0.247, Figure D). For the detection of an elevated LVEDP above 15 mmHg, a cut off value for the SW velocity at MVC of 4.395 m/s (Figure A) was associated with a sensitivity of 91.3% and a specificity of 90.9%. Conclusions End-diastolic shear wave velocities, measured by high frame rate shear wave elastography, showed a significant correlation with the end-diastolic filling pressure of the LV and allowed to differentiate normal from elevated filling pressure which indicates a potential clinical value of the new method for a non-invasive and direct assessment of LV diastolic function. More patients will be included to confirm these findings. Abstract Figure.

Shear wave elastography: can we estimate filing pressures?

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A.E Werner ◽  
S Bezy ◽  
M Orlowska ◽  
G Kubiak ◽  
W Desmet ◽  
...  
Keyword(s):  
Diastolic Function ◽  
Shear Wave ◽  
Propagation Velocity ◽  
Shear Wave Elastography ◽  
Left Ventricular ◽  
Filling Pressure ◽  
Frame Rate ◽  
Funding Source ◽  
High Frame Rate ◽  
Non Invasive

Abstract Background The assessment of the left ventricular diastolic function is complex, as there is no single non-invasive parameter that provides a direct measurement of myocardial relaxation, myocardial compliance, or – as a surrogate - LV filling pressure. Estimation of diastolic function is therefore based on the combination of many parameters. Shear wave (SW) elastography (SWE) is a novel method based on high frame rate echocardiography. SWs occur after mechanical excitation of the myocardium, e.g. after mitral valve closure (MVC), and their propagation velocity is directly related to myocardial stiffness (MS). Purpose The aim of this study was to investigate if velocities of natural shear waves are related to MS at end diastole (ED) and, thus, could be used to estimate left ventricular end-diastolic pressures (LVEDP) as marker of diastolic function. Methods So far, we have prospectively enrolled 30 patients with a wide range of diastolic function, scheduled for heart catheterization so that LV filling pressures could be invasively measured. Patients with severe aortic stenosis, mitral stenosis of any degree and a more than moderate mitral regurgitation, as well as regional myocardial abnormalities or dysfunction in the anteroseptal wall were excluded. Echocardiography was performed immediately after catheterization. SW elastography in parasternal long axis views of the left ventricle (LV) was performed using an experimental scanner (HD-PULSE) at 1100±250 frames per second. Tissue acceleration maps were extracted from an anatomical M-mode line along the midline of the LV septum. The SW propagation velocity at MVC was measured as the slope on the M-mode acceleration map (Figure A). Results SW velocities at ED correlated very well with the invasively measured LVEDP (r=0.815, p<0.001, Figure B). In comparison, classical echocardiographic parameters correlated only weakly or not with LVEDP (E/A: r=0.528, p=0.036, Figure C; E/e': r=−0.169, p=0,531, Figure D) with LVEDP. For the detection of an elevated LVEDP above 15 mmHg, a cut off value for the SW velocity at MVC of 3.75 m/s was associated with a Sensitivity of 92.9% and a Specificity of 83.3%. Conclusions End-diastolic shear wave velocities, measured by high frame rate shear wave elastography, showed a significant correlation with the end-diastolic filling pressure of the LV indicating a potential clinical value of the new method for a non-invasive and direct assessment of LV diastolic function. More patients will be included to confirm these findings. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Fonds Wetenschappelijk Onderzoek Flanderen (Research Foundation Flanders)

Validation of novel biomarkers to assess cardiac diastolic function extracted using a high frame rate speckle tracking algorithm

2021 ◽  
Author(s):  
Konstantina Papangelopoulou ◽  
Marta Orlowska ◽  
Stephanie Bezy ◽  
Aniela Petrescu ◽  
Annegret Werner ◽  
...  
Keyword(s):  
Diastolic Function ◽  
Speckle Tracking ◽  
Tracking Algorithm ◽  
Frame Rate ◽  
High Frame Rate ◽  
Novel Biomarkers

Impact of marathon running on cardiac structure and function in recreational runners

2004 ◽  
Vol 108 (1) ◽  
pp. 73-80 ◽  
Author(s):  
Gregory WHYTE ◽  
Keith GEORGE ◽  
Robert SHAVE ◽  
Ellen DAWSON ◽  
Claire STEPHENSON ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Diastolic Function ◽  
Limit Of Detection ◽  
Left Ventricular ◽  
Doppler Imaging ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Diastolic Filling ◽  
Lv Function ◽  
Marathon Running ◽  
Recreational Runners

The present study examined the relationship between LV (left ventricular) function, markers of cardiac-specific damage and markers of oxidative stress in recreational runners following a marathon. Runners (n=52; 43 male and nine female; age, 35±10 years; height, 1.74±0.08 m; body mass, 75.9±8.9 kg) were assessed pre- and immediately post-marathon. LV function was assessed using standard M-mode two-dimensional Doppler echocardiography and TDI (tissue-Doppler imaging) echocardiography. Serum was analysed for cTnT (cardiac troponin-T), TEAC (Trolox equivalent antioxidant capacity; a measure of total antioxidant capacity), MDA (malondealdehyde) and 4-HNE (4-hydroxynonenal). A strong relationship was observed between standard and TDI echocardiography for all functional measures. Diastolic function was altered post-marathon characterized by a reduction in E (peak early diastolic filling: 0.79±0.11 compared with 0.64±0.16 cm/s; P<0.001), an increase in A (peak late diastolic filling: 0.48±0.11 compared with 0.60±0.12 cm/s; P<0.001) and a resultant decrease in E/A (ratio of E to A; 1.71±0.48 compared with 1.10±0.31; P<0.001). Ejection fraction remained unchanged post-marathon. Thirty-two runners presented with cTnT values above the lower limit of detection for the assay (0.01 μg/l), and 20 runners presented post-marathon with cTnT values above the acute myocardial infarction cut-off value (0.05 μg/l). No significant correlations were observed between cTnT and any functional measurements. MDA (2.90±1.58 compared with 3.59±1.47 μmol/l) and TEAC (1.80±0.12 compared with 1.89±0.21 mmol/l) were significantly increased post-marathon, but were unrelated to changes in function or cTnT. In conclusion, the present study demonstrated a reduction in diastolic function and widespread evidence of minimal cardiac damage following a marathon in recreational runners. The mechanism(s) underpinning the altered function and appearance of cTnT appear unrelated to reactive oxygen species.

P4582The role of TDI diastolic measurements for prognostic prediction early and late after surgical ventricular reconstruction

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Iliuta
Keyword(s):  
Diastolic Function ◽  
Left Ventricular ◽  
Doppler Imaging ◽  
Function Evaluation ◽  
Diastolic Filling ◽  
Lv Function ◽  
Surgical Ventricular Reconstruction ◽  
Ventricular Reconstruction ◽  
The Impact ◽  
Dimension Index

Abstract Aim 1. To evaluate the impact of preoperative left ventricular (LV) diastolic performance on early and late outcomes in patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG) and surgical ventricular reconstruction (SVR). 2. To investigate LV diastolic function dynamics according to the results of tissue Doppler imaging (TDI) in these patients. 3. To assess the echographic predictors for persistence of the restrictive LV diastolic filling pattern (LVDFP) late after CABG and SVR. Material and method Prospective study on 157 pts with LV systolic dysfunction (LVEF <30%) who underwent CABG and SVR, evaluated including TDI preoperatively, early (<1 month), medium (3 and 12 months) and late postoperatively (mean 4,8 years). Statistical analysis used SYSTAT and SPSS. The primary outcome was the time to death from any cause or hospitalization for cardiac causes. Results 1. The preoperative restrictive LVDFP was an independent and predominant predictor for increasing the early and late postoperative risk of cardiovascular events (p=0.001). At 5 years postoperatively, cardiovascular event-free survival was significantly higher in pts with nonrestrictive LVDFP (75%) compared with restrictive LVDFP (55,74%) (p<0.0001). 2. Conventional transmitral diastolic Doppler indices before and after CABG +SVR remained unchanged. TDI showed significant improvement before and in 3 and 12months postoperatively of both LV systolic (S: 6.1±0.9, 7.5±1.1 and 7.3±1.2 cm/sec, p<0.01) and diastolic function (e': 7.2±1.8, 8.3±1.4 and 8.8±1.5 cm/sec; E/e' ratio: 17.8±2.1, 13.1±1.7 and 11.3±1.8; Vp 3.2±0.55, 2.4±0.28 and 1.9±0.26, p<0.01). 3. The evolution of LVEF, LV end-diastolic volume (LVEDV) and mitral regurgitation (MR) severity was different in nonrestrictive group (early and late postoperatively these variables improved) compared with restrictive group (late after surgery the variables deteriorated: LVEF from 27±8% to 22±6%, LVEDV from 181±49 to 234±63 cm3 and MR degree from 0.9±0.6 to 1.8±0.7; p<0.005). 4. Regression analysis identified as predictors for persistence of a restrictive LVDFP late after surgery: E/E' ratio >14 (RR=19.3), LA dimension index >30 mm/m2 (RR=9.2), LVEDV >200 cm3 (RR=9.6), severe PHT (RR=11.4), 2 degree MR (RR=14.8). Conclusions 1. TDI evaluation demonstrate significant improvement of LV systolic diastolic function in CABG + SVR pts, regardless of transmitral flow pattern. TDI is more sensitive and preload independent method of LV function evaluation. 2. The preoperative LVDFP has an independent and incremental prognostic value in CABG+SVR pts, strongly related to higher mortality with aggravation of LV systolic function, MR severity or LV remodeling. This might be attributable to deterioration of diastolic function induced by SVR. 3. Late after CABG+SVR the restrictive LVDFP persistence was predicted by: E/E' ratio >14, LA dimension index >30 mm/m2, LVEDV >200 cm3, severe PHT and 2 degree MR.

scholarly journals 420 Vortex formation in the pre-ejection phase in the left ventricle

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
A Daae ◽  
M Wigen ◽  
L Lovstakken ◽  
A Stoylen
Keyword(s):  
Left Ventricle ◽  
Speckle Tracking ◽  
Plane Waves ◽  
Vortex Formation ◽  
Left Ventricular ◽  
Frame Rate ◽  
Doppler Imaging ◽  
High Temporal Resolution ◽  
Lateral Part ◽  
Ejection Phase

Abstract Funding Acknowledgements Central Norway Regional Health Authority Background/Introduction: Vortex formation during left ventricular filling have been described since the 1980’s. We have investigated vortices in the left ventricle (LV) in healthy adults with a new technology based on high frame rate vector flow imaging (VFI) using blood speckle tracking. Purpose In this study we investigated the intraventricular flow pattern during the pre-ejection period. Material and methods We examined 21 healthy volunteers with a GE E95 ultrasound scanner, both in ordinary clinical mode and with an experimental setup. The latter was developed to achieve high frame rates by utilizing plane waves in combination with ECG-gating over multiple (5-6) heart cycles, allowing continuous acquisition of &gt; 3500 FPS. Blood speckle tracking followed by model based regularization was used to obtain vector flow velocity measurements. Results During the pre-ejection phase we observed blood flow from the apex to the basis of the LV along the septum. At the base, the flow is deflected. A basal vortex is then created just above the mitral valve, which persists into the isovolumetric contraction (IVC). The lateral part of the vortex is then seen as an apically directed flow during IVC, as shown in the illustration. The vortex is also visible in the first phase of the ejection; the part of the blood in the LV not passing through the aortic valve is deflected and continues to conserve this vortex. These findings correspond to patterns found in colour M-Mode (CMM), showing a column of blood toward the apex in the IVC/early ejection phase. Time from peak R to the first sighting of this IVC vortex, and to the pre-ejection spike in tissue Doppler imaging (TDI), are similar, as reported in table 1. Conclusion(s): Our imaging setup allows for a very high temporal resolution (&gt;3500 FPS), and enables VFI using blood speckle tracking, without using a contrast agent. We observed an intraventricular vortex during pre-ejection and into early ejection, with the same direction as the later vortices seen in filling. Initiation of this vortex may be conserved energy from late filling. This vortex is simultaneous with the pre-ejection spike in TDI. We postulate that this IVC vortex contributes to the closing of the anterior mitral leaflet in the IVC. As we also observe this vortex during the early ejection phase, we believe it may conserve rotational energy into early filling. Table 1 Timing of the IVC vortex and the pre-ejection spike in TDI Mean Median SD Min Max Time between R and the basal vortex during IVS (ms) 16,7 16 15,1 -13 47 Time between R and the pre-ejection spike TDI (ms) 16,3 21 14,4 -10 36 Abstract 420 Figure.

scholarly journals Does breathing technique improve diastolic function of left ventricular?

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
GS Smyrnova ◽  
TM Babkina
Keyword(s):  
Diastolic Function ◽  
Standard Therapy ◽  
Early Recognition ◽  
Diastolic Heart Failure ◽  
Hypertensive Heart Disease ◽  
Left Ventricular ◽  
Doppler Imaging ◽  
Diastolic Filling ◽  
Clinical Disorder ◽  
Yogic Breathing

Abstract Funding Acknowledgements Type of funding sources: None. Background. Diastolic heart failure (HF) is an important clinical disorder mainly seen in the elderly patients with hypertensive heart disease. Early recognition and appropriate therapy of diastolic dysfunction is advisable to prevent further progression of the illness. There is no specific therapy to improve diastolic function directly. Mechanisms by which yoga may improve cardiac function and reduce myocardial stress are speculated at this time. Purpose. The study’s purpose was to analyze the effects of full yogic breathing on diastolic function of left ventricular in patients with HF. Methods. One hundred and two patients with chronic HF (males, 62%; mean age, 68.2 ± 4.5 years) were randomly assigned to full yogic breathing training plus standard therapy (n = 48) or standard therapy alone (n = 54). Patients in both groups were assessed at baseline and 6 months after randomization. Echocardiographic evaluation of diastolic function has been performed by measurement of transmitral flow parameters including the early (E) and late (A) diastolic filling velocities, the E/A ratio, and the E deceleration time (DT) with conventional pulsed wave Doppler. The medial and lateral early diastolic mitral annular velocities, and the E/Ea ratio were also assessed by tissue Doppler imaging. Results. There were no significant differences in demographic and baseline characteristics between participants. By the end of the observation period significant diastolic function improvements were observed in yogic breathing group. E/A ratio (from 1.02 ± 0.9 to 1.13 ± 0.7; from 1.01 ± 0.7 to 1.08 ± 0.8) was increased, whereas E DT (from 238 ± 16 to 216 ± 17 ms; from 229 ± 20 to 221 ± 19 ms) and E/Ea ratio (from 9.87 ± 1.34 to 8.71 ± 0.79; from 9.77 ± 1.26 to 9.36 ± 0.68) were decreased in yogic breathing group compared with standard therapy alone group. Conclusion. Yoga breathing practice for 6 months showed a significant improvement in diastolic function of left ventricular.

scholarly journals Speckle-Tracking Echocardiography with Novel Imaging Technique of Higher Frame Rate

2021 ◽  
Vol 10 (10) ◽  
pp. 2095
Author(s):  
Kana Fujikura ◽  
Mohammed Makkiya ◽  
Muhammad Farooq ◽  
Yun Xing ◽  
Wayne Humphrey ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Speckle Tracking ◽  
Speckle Tracking Echocardiography ◽  
Systolic Function ◽  
Myocardial Strain ◽  
Left Ventricular Systolic Function ◽  
Left Ventricular ◽  
Frame Rate ◽  
Normal Left Ventricular ◽  
Echocardiographic Images

Background: The accuracy of speckle-tracking echocardiography (STE) depends on temporal resolution. The goal of this study was to demonstrate the feasibility of relatively high frame rate (rHi-FR) (~200 fps) for STE. Methods: In this prospective study, echocardiographic images were acquired using clinical scanners on patients with normal left ventricular systolic function using rHi-FR and conventional frame rate (Reg-FR) (~50 FPS). GLS values were evaluated on apical 4-, 2- and 3-chamber images acquired in both rHi-FR and Reg-FR. Inter-observer and intra-observer variabilities were assessed in rHi-FR and Reg-FR. Results: There were 143 echocardiograms evaluated in this study. The frame rate of rHi-FR was 190 ± 25 and Reg-FR was 50 ± 3, and the heart rate was 71 ± 13. Absolute strain values measured in rHi-FR were significantly higher than those measured in Reg-FR (all p < 0.001). Inter-observer and intra-observer correlations were strong in both rHi-FR and Reg-FR. Conclusions: We demonstrated that absolute strain values were significantly higher using rHi-FR when compared with Reg-FR. It is plausible that higher temporal resolution enabled the measurement of myocardial strain at desired time point. Further investigations are necessary to evaluate the value of rHi-FR to assess myocardial strain in the setting of tachycardia.

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