Assessment of left ventricular mechanics in right ventricular overload using in silico rat models

Abstract Background To preserve cardiac function in overload conditions, the RV adapts by developing muscular hypertrophy through progressive tissue remodelling. This process may lead to a vicious cycle with detrimental effects on RV diastolic and systolic function, as seen in pulmonary arterial hypertension (PAH) patients [1]. However, how RV overload affects LV function and remodelling remains an open question [2]. Computational models of cardiac physiology offer an opportunity for investigating mechanisms difficult or impossible to analyse otherwise due to the existence of overlapping factors and technical limitations. Aim This study aims to assess the acute effects of RV overload and increased myocardial passive stiffness on the LV mechanical properties in an anatomically-based computational model of healthy rat heart. Methods A computational simulation pipeline of cardiac mechanics based on the Holzapfel-Ogden model has been implemented using MR images from a healthy rat. Whereas LV function was modelled realistically using catheter measurements conducted on the same subject than the MR imaging, RV function was based on representative literature values for healthy and PAH rats with RV overload. The following cases were defined (Fig. 1): CTRL, with normal RV function; PAH1, with 30% increase in RV ESV (end-systolic volume) and 15% increase in RV ESP (end-systolic pressure) in comparison to CTRL; and PAH2, with 60% increase in RV ESV and 30% increase in RV ESP compared to CTRL. The cardiac cycle was simulated for all cases whilst fitting the experimentally measured LV pressure and volume values from a healthy rat, which allowed quantifying the effects of RV overload on LV function. Results The increase of average circumferential strain in the LV correlated with the degree of RV overload simulated (CTRL: −8.7%, PAH1: −8.9%, PAH2: −9.2%), whilst average radial (CTRL: 35.2%, PAH1: 34.8%, PAH2: 30.3%) and longitudinal strains decreased (CTRL: −7.7%, PAH1: −7.4%, PAH2: −6.6%), as seen in Fig.2. However, regional differences in strain were significant: under RV overload conditions, circumferential strain increased in the septum (−3.5% difference in PAH2 vs. CTRL) but lower values were observed in the lateral wall (+1.7% difference in PAH2 vs. CTRL). Cardiac function of case PAH2 was simulated also with increased myocardial passive stiffness (2.67 kPa instead of 1.34 kPa) which presented a mild strain increase in the mid LV ventricle in comparison to PAH2 with normal stiffness (circumferential strain: −0.8%, radial strain: +0.5%, longitudinal strain: −0.2%). Conclusion Our study provides mechanistic evidence on how RV overload and increased passive myocardial stiffness causes a redistribution of strain and fibre stress in the LV, which may play a significant role in LV remodelling and function. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): K.G. Jebsen Center for Cardiac Research Figure 1. Pressure – volume loops Figure 2. Mean mid-LV strains

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Biventricular pacing during cardiac magnetic resonance imaging

EP Europace ◽

10.1093/europace/euz289 ◽

2019 ◽

Cited By ~ 1

Author(s):

Hajnalka Vago ◽

Csilla Czimbalmos ◽

Roland Papp ◽

Liliana Szabo ◽

Attila Toth ◽

...

Keyword(s):

Cardiac Magnetic Resonance ◽

Magnetic Resonance ◽

Circumferential Strain ◽

Biventricular Pacing ◽

Radial Strain ◽

Left Ventricular ◽

Volume Index ◽

Lv Function ◽

Resonance Imaging

Abstract Aims We aimed to assess the effect of cardiac resynchronization on left ventricular (LV) function, volumes, geometry, and mechanics in order to demonstrate reverse remodelling using cardiac magnetic resonance (CMR) with resynchronization on. Methods and results New York Heart Association (NYHA) Class II–III patients on optimal medical therapy with LV ejection fraction (LVEF) ≤35%, and complete LBBB with broad QRS (>150 ms) were prospectively recruited. Cardiac magnetic resonance examination was performed at baseline and at 6-month follow-up, applying both biventricular and AOO pacing. The following data were measured: conventional CMR parameters, remodelling indices, global longitudinal, circumferential, radial strain, global dyssynchrony [mechanical dispersion (MD) defined as the standard deviation of time to peak longitudinal/circumferential strain in 16 LV segments], and regional dyssynchrony (maximum differences in time between peak septal and lateral transversal displacement). Thirteen patients (64 ± 7 years, 38% male) were enrolled. Comparing the baseline and follow-up CMR parameters measured during biventricular pacing, significant increase in LVEF, and decrease in LV end-diastolic volume index (LVEDVi) and LV end-systolic volume index (LVESVi) were found. Left ventricular remodelling indices, global longitudinal, circumferential, and radial strain values showed significant improvement. Circumferential MD decreased (20.5 ± 5.5 vs. 13.4 ± 3.4, P < 0.001), while longitudinal MD did not change. Regional dyssynchrony drastically improved (362 ± 96 vs. 104 ± 66 ms, P < 0.001). Applying AOO pacing resulted in an immediate deterioration in LVEF, LVESVi, circumferential strain, global and regional dyssynchrony. Conclusion Cardiac magnetic resonance imaging during biventricular pacing is feasible and enables a more precise quantification of LV function, morphology, and mechanics. As a result, it may contribute to a better understanding of the effects of resynchronization therapy and might improve responder rate in the future.

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Abstract 1879: Global Lv Strain Is An Accurate Measure For Scar Extent After Myocardial Infarct. A Comparison Of Longitudinal, Circumferential And Radial Strain Measurements

Circulation ◽

10.1161/circ.116.suppl_16.ii_403 ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Trond Vartdal ◽

Ola Gjesdal ◽

Thomas Helle-Valle ◽

Ketil Lunde ◽

Einar Hopp ◽

...

Keyword(s):

Longitudinal Strain ◽

Roc Analysis ◽

Circumferential Strain ◽

Myocardial Infarct ◽

Radial Strain ◽

Late Enhancement ◽

Left Ventricular ◽

Lv Function ◽

Transmural Infarct ◽

First Myocardial Infarction

Purpose: Recent progress by speckle tracking echocardiography (STE) provides the opportunity to assess left ventricular (LV) function in 3 dimensions. We studied LV longitudinal, circumferential and radial strain and calculated which strain parameter that correlated best to myocardial scar mass in patients with chronic ischemic heart disease. Methods: 40 patients (aged 58 ± 10 years, 9 women) were studied 8.5 ± 5.4 months after a first myocardial infarction. LV infarct mass was estimated by late enhancement MRI and compared to global LV strain. Global LV strain is calculated by averaging all segmental peak systolic strain values by STE in a 16 segment model. Longitudinal strain was assessed from 3 apical views, and circumferential- and radial strain from 3 short axis slices (apical, mid and basal). Results: In average, 7.9 ± 4.1 segments and a total of 34 ± 27g were infarcted. Transmural infarct (≥50% transmural) was found in 25 patients. All global strains correlated significantly with infarct mass (figure ). In a ROC analysis, longitudinal strain was superior to identify substantial (≥30g) myocardial infarcts (sensitivity = 0.80, specificity = 0.85). Circumferential strain was best to identify minor (≥5g) myocardial infarcts (sensitivity = 0.82, specificity = 0.86). Conclusion: Assessment of strain in all 3 major dimensions reflects decreased LV function due to ischemic myocardium. Global longitudinal- and circumferential- strains are excellent markers to identify patients with myocardial infarct. Figure: Correlation plots

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Cardiac function is normal in most patients recovered from COVID-19

European Heart Journal ◽

10.1093/eurheartj/ehab724.0265 ◽

2021 ◽

Vol 42 (Supplement_1) ◽

Author(s):

J Tangen ◽

P Aukrust ◽

A Barrat-Due ◽

M Troseid ◽

I Christoffer Olsen ◽

...

Keyword(s):

Cardiac Function ◽

Global Longitudinal Strain ◽

Normal Function ◽

Left Ventricular ◽

Lv Function ◽

Myocardial Inflammation ◽

Slight Reduction ◽

Free Wall ◽

Very High Frequency ◽

Rv Function

Abstract Background There are conflicting results regarding impaired cardiac function in patients that have recovered from COVID-19. Cardiovascular magnetic resonance (CMR) studies have revealed a very high frequency of cardiac involvement (78%) and ongoing myocardial inflammation (60%) in patients recently recovered from COVID-19. Findings are advocating further investigation of the long-term myocardial consequences of COVID-19 disease. Purpose We aimed to investigate left ventricular (LV) and right ventricular (RV) function by a comprehensive echocardiographic study in patients recovered from COVID-19 infection 3 months after admission to hospital. Methods All patients (n=92) had been hospitalized for COVID-19 and were examined with echocardiography three months after hospitalization. They were 59±13 years, and 43% were women. LV function was assessed by ejection fraction (EF) and global longitudinal strain (GLS) and RV function was measured by fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE) and RV GLS free wall. Tricuspid regurgitation pressure gradient was measured to estimate pulmonary artery pressure. Results LV EF was 63±6% and LV GLS was −18.6±2.2%. All patients had normal EF >53%, but 10 showed signs of subtle impaired LV function by LV GLS (≥ −16%). Only two of these did not have hypertension, LV hypertrophy, diabetes or other preexisting diagnosis of heart disease explaining subtle LV dysfunction. All had normal RV FAC (48±7%) and TAPSE (2.3±0.3 cm). We found modestly impaired RV longitudinal function (RV GLS free wall >−25%) in 30% patients, but none had RV GLS worse than −20%. One-third of all patients with reduced RV GLS had signs of elevated pulmonary arterial pressures, which might impact the assessment of RV function. Conclusions Traditional echocardiographic parameters showed normal function in all hospitalized COVID-19 patients three months after hospital admittance. Approximately one-third had subtle ventricular dysfunction detected by sensitive echocardiographic methods, but these findings could mostly be explained by systemic or pulmonary hypertension. We cannot, however, exclude that a slight reduction in cardiac function in a minority of our patients was caused by the COVID-19 infection. FUNDunding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): National Clinical Therapy Research in the Specialist Health Services, Norway

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Abstract 2823: Right Ventricular Septal Versus Apical Pacing: Long Term Impact On Left Ventricular Synchrony And Function

Circulation ◽

10.1161/circ.118.suppl_18.s_781-d ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Arnold Ng ◽

Christine Allman ◽

Jane Vidaic ◽

Hui Tei ◽

Andrew P Hopkins ◽

...

Keyword(s):

Right Ventricular ◽

Circumferential Strain ◽

Radial Strain ◽

Left Ventricular ◽

Volume Index ◽

Lv Function ◽

Systolic Volume ◽

Septal Pacing ◽

Normal Controls

Background: Right ventricular (RV) septal pacing has been advocated as an alternative to RV apical pacing to avoid long term detrimental effects. There is conflicting evidence on the benefits of RV septal pacing. No studies have previously compared left ventricular (LV) strain and dyssynchrony between different pacing sites and utilized echocardiography to determine pacing sites. Methods: 55 patients (22 normal controls, 17 RV septal and 17 RV apical pacing) were recruited. LV circumferential and radial strain were determined in the midventricular short axis views. Circumferential and radial strain synchrony, and longitudinal systolic (SDTs) and diastolic (SDTe) dyssynchrony indices were determined. Echocardiographic determination of pacing sites were compared with ECG and chest x-ray (CXR). Results: The median pacing durations were 436 days for RV septal and 2398 days for RV apical pacing. Mean QRS duration were significantly shorter for septal than apical pacing and normal controls (139.8 ± 22.6 vs. 162.4 ± 22.9 vs. 85.9 ± 15.2 msec respectively, p < 0.001). LV mass index, end-systolic volume index and ejection fraction were more impaired in RV septal than apical pacing (108.2 ± 27.2 vs. 91.5 ± 15.4 g/m 2 , 21.3 ± 3.7 vs. 19.4 ± 9.3mL/m 2 , 47.6 ± 8.5 vs. 54.2 ± 7.8% respectively, all p < 0.05). RV septal pacing was associated with more impaired circumferential strain (p < 0.001) and worse circumferential strain dyssynchrony (p = 0.02) than apical pacing and normal controls. There were no significant differences in radial strain, radial strain dyssynchrony or SDTs. RV septal pacing consisted of a heterogeneous group of different pacing sites on echocardiography, and there was only modest agreement between echocardiographic, ECG and CXR determinations of pacing sites. Conclusions: RV septal pacing was associated with poorer long term LV function and greater dyssynchrony than RV apical pacing and normal controls.

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Impact of BMI z-score On Left Ventricular Mechanics in a Pediatric Population

10.21203/rs.3.rs-1024256/v1 ◽

2021 ◽

Author(s):

Justine Paysal ◽

Etienne Merlin ◽

Emmanuelle Rochette ◽

Daniel Terral ◽

Stephane Nottin

Keyword(s):

Pediatric Population ◽

Global Longitudinal Strain ◽

Left Ventricular ◽

Female Adolescents ◽

Lv Function ◽

Z Score ◽

Ventricular Mechanics ◽

Lv Mass ◽

Left Ventricular Mechanics ◽

Longitudinal Strains

Abstract Background: Adolescent weight disorders ranging from anorexia nervosa (AN) to obesity (OB) can impact the heart by causing opposite alterations in its morphology, suggesting a direct impact of BMI on the heart. Cardiac function is relatively preserved as assessed by standard ultrasound methods. However, few studies have used speckle-tracking echocardiography (STE), which can detect subtle alterations of left ventricular (LV) function by evaluating deformations. The aim of this study was to assess the link between BMI z-score of female adolescents and myocardial function. Methods: Ninety-one female adolescents comprising 26 AN patient (age 14.6 ± 1.9 y), 28 OB patients (age 13.2 ± 1.4 y), and 37 controls (age 14.0 ± 2.0 y) underwent STE to assess LV morphology and myocardial regional deformations. Findings: The BMI z-score of our population ranged from −4.6 to 5.2. LV morphological remodeling was significantly and positively correlated with BMI z-score (R² = 0.456, p < 0.0001 for LV mass). Global longitudinal strain (LS) and regional LS recorded at the mid and apical levels were significantly correlated with BMI z-score (R² = 0.196, p = 0.0001 and R² = 0.274, p < 0.0001 respectively for apical and medial LS). Circumferential strains and twisting mechanics were not correlated with BMI z-score. Fibrinogen and SBP were the main variables explaining the alteration of longitudinal strains. Conclusion: A impact of BMI z-score on LV mechanics was observed especially on medial and apical LS. Neither circumferential nor twisting mechanics were altered by BMI z-score in female adolescents.

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Myocardial deformation in patients with a single left ventricle using 2D cardiovascular magnetic resonance feature tracking: a case–control study

The International Journal of Cardiovascular Imaging ◽

10.1007/s10554-021-02230-2 ◽

2021 ◽

Author(s):

Fabian Strodka ◽

Jana Logoteta ◽

Roman Schuwerk ◽

Mona Salehi Ravesh ◽

Dominik Daniel Gabbert ◽

...

Keyword(s):

Cardiovascular Magnetic Resonance ◽

Magnetic Resonance ◽

Left Ventricle ◽

Feature Tracking ◽

Systolic Function ◽

Radial Strain ◽

Left Ventricular ◽

Lv Function ◽

Significant Difference ◽

Lv Volumes

AbstractVentricular dysfunction is a well-known complication in single ventricle patients in Fontan circulation. As studies exclusively examining patients with a single left ventricle (SLV) are sparse, we assessed left ventricular (LV) function in SLV patients by using 2D-cardiovascular magnetic resonance (CMR) feature tracking (2D-CMR-FT) and 2D-speckle tracking echocardiography (2D-STE). 54 SLV patients (11.4, 3.1–38.1 years) and 35 age-matched controls (12.3, 6.3–25.8 years) were included. LV global longitudinal, circumferential and radial strain (GLS, GCS, GRS) and strain rate (GLSR, GCSR, GRSR) were measured using 2D-CMR-FT. LV volumes, ejection fraction (LVEF) and mass were determined from short axis images. 2D-STE was applied in patients to measure peak systolic GLS and GLSR. In a subgroup analysis, we compared double inlet left ventricle (DILV) with tricuspid atresia (TA) patients. The population consisted of 19 DILV patients, 24 TA patients and 11 patients with diverse diagnoses. 52 patients were in NYHA class I and 2 patients were in class II. Most SLV patients had a normal systolic function but median LVEF in patients was lower compared to controls (55.6% vs. 61.2%, p = 0.0001). 2D-CMR-FT demonstrated reduced GLS, GCS and GCSR values in patients compared to controls. LVEF correlated with GS values in patients (p < 0.05). There was no significant difference between GLS values from 2D-CMR-FT and 2D-STE in the patient group. LVEF, LV volumes, GS and GSR (from 2D-CMR-FT) were not significantly different between DILV and TA patients. Although most SLV patients had a preserved EF derived by CMR, our results suggest that, LV deformation and function may behave differently in SLV patients compared to healthy subjects.

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Effects of avertin versus xylazine-ketamine anesthesia on cardiac function in normal mice

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.281.5.h1938 ◽

2001 ◽

Vol 281 (5) ◽

pp. H1938-H1945 ◽

Cited By ~ 70

Author(s):

Chari Y. T. Hart ◽

John C. Burnett ◽

Margaret M. Redfield

Keyword(s):

Cardiac Function ◽

Diastolic Pressure ◽

Systolic Function ◽

Pressure Rise ◽

Left Ventricular ◽

Lv Function ◽

Ketamine Anesthesia ◽

The Difference ◽

And Function ◽

Derivatives Of

Anesthetic regimens commonly administered during studies that assess cardiac structure and function in mice are xylazine-ketamine (XK) and avertin (AV). While it is known that XK anesthesia produces more bradycardia in the mouse, the effects of XK and AV on cardiac function have not been compared. We anesthetized normal adult male Swiss Webster mice with XK or AV. Transthoracic echocardiography and closed-chest cardiac catheterization were performed to assess heart rate (HR), left ventricular (LV) dimensions at end diastole and end systole (LVDd and LVDs, respectively), fractional shortening (FS), LV end-diastolic pressure (LVEDP), the time constant of isovolumic relaxation (τ), and the first derivatives of LV pressure rise and fall (dP/d t max and dP/d t min, respectively). During echocardiography, HR was lower in XK than AV mice (250 ± 14 beats/min in XK vs. 453 ± 24 beats/min in AV, P < 0.05). Preload was increased in XK mice (LVDd: 4.1 ± 0.08 mm in XK vs. 3.8 ± 0.09 mm in AV, P < 0.05). FS, a load-dependent index of systolic function, was increased in XK mice (45 ± 1.2% in XK vs. 40 ± 0.8% in AV, P < 0.05). At LV catheterization, the difference in HR with AV (453 ± 24 beats/min) and XK (342 ± 30 beats/min, P < 0.05) anesthesia was more variable, and no significant differences in systolic or diastolic function were seen in the group as a whole. However, in XK mice with HR <300 beats/min, LVEDP was increased (28 ± 5 vs. 6.2 ± 2 mmHg in mice with HR >300 beats/min, P < 0.05), whereas systolic (LV dP/d t max: 4,402 ± 798 vs. 8,250 ± 415 mmHg/s in mice with HR >300 beats/min, P < 0.05) and diastolic (τ: 23 ± 2 vs. 14 ± 1 ms in mice with HR >300 beats/min, P < 0.05) function were impaired. Compared with AV, XK produces profound bradycardia with effects on loading conditions and ventricular function. The disparate findings at echocardiography and LV catheterization underscore the importance of comprehensive assessment of LV function in the mouse.

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Abstract 1874: Circumferential and Radial Left Ventricular Mechanics in Elderly Canines with Hypertensive Heart Disease

Circulation ◽

10.1161/circ.116.suppl_16.ii_401-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Josef Korinek ◽

Brian P Shapiro ◽

Carolyn S Lam ◽

Donna M Meyer ◽

Margaret M Redfield

Keyword(s):

Heart Disease ◽

Ejection Fraction ◽

Myocardial Dysfunction ◽

Radial Strain ◽

Hypertensive Heart Disease ◽

Wall Stress ◽

Strain Imaging ◽

Left Ventricular ◽

Doppler Imaging ◽

Ventricular Mechanics

Introduction: Cross-sectional studies in patient with hypertensive heart disease (HHD) and heart failure with normal ejection fraction (HFnlEF) suggested impairment of longitudinal myocardial mechanics as assessed by tissue Doppler imaging. It has been suggested that enhanced circumferential, and/or radial LV mechanics or LV remodeling compensates for depression in longitudinal function and thus, preserves EF in HHD or HFnlEF. Hypothesis : We hypothesized that if longitudinal performance is depressed, whether due to increased afterload or to intrinsic myocardial dysfunction, circumferential and radial LV mechanics would also be effected. To test this hypothesis, we used an aged canine model of hypertension. Methods: Elderly dogs (n=22) underwent bilateral renal wrapping to induce hypertension. 2D echocardiography (mid-short axis views) was performed before and 8 weeks after renal wrapping; peak radial (PR) and peak circumferential (PC) regional strains were measured by speckle tracking averaging data from 6 segments. Ejection fraction (EF), LV mass index (LVMI), systolic blood pressure (SBP), and circumferential wall stress (CWS) were assessed as well. Results : See table . PR correlated with PC (r=0.65), EF (r=0.67), LWMI (r=0.71) and CWS (r=0.58) (p<0.005 for all). PC correlated also with EF (r=0.60), LWMI (r=0.49) and CWS (r=0.48) (p<0.01 for all). The relationship between EF and CWS (r 2 =0.64, p<0.001) was modified by the addition of either PC (r 2 =0.74, p for PC =0.005) or PR strain(r 2 =0.69, p for PR =0.04). Conclusions : These data show that development of hypertension with LV hypertrophy does not enhance but impairs circumferential and radial LV mechanics as assessed with strain imaging, and that like EF, circumferential and radial strain are related to afterload (wall stress). However, both confer additional information regarding contractility. Conclusions regarding myocardial function based on strain imaging must account for its load dependence.

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Dietary Calanus oil recovers metabolic flexibility and rescues postischemic cardiac function in obese female mice

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00191.2019 ◽

2019 ◽

Vol 317 (2) ◽

pp. H290-H299 ◽

Cited By ~ 3

Author(s):

Kirsten M. Jansen ◽

Sonia Moreno ◽

Pablo M. Garcia-Roves ◽

Terje S. Larsen

Keyword(s):

Fatty Acid ◽

Cardiac Function ◽

Glucose Oxidation ◽

Myocardial Metabolism ◽

Dietary Supplementation ◽

Left Ventricular ◽

Lv Function ◽

Marine Oil ◽

Normal Chow ◽

Postischemic Recovery

The aim of this study was to find out whether dietary supplementation with Calanus oil (a novel marine oil) or infusion of exenatide (an incretin mimetic) could counteract obesity-induced alterations in myocardial metabolism and improve postischemic recovery of left ventricular (LV) function. Female C57bl/6J mice received high-fat diet (HFD, 45% energy from fat) for 12 wk followed by 8-wk feeding with nonsupplemented HFD, HFD supplemented with 2% Calanus oil, or HFD plus exenatide infusion (10 µg·kg−1·day−1). A lean control group was included, receiving normal chow throughout the whole period. Fatty acid and glucose oxidation was measured in ex vivo perfused hearts during baseline conditions, while LV function was assessed with an intraventricular fluid-filled balloon before and after 20 min of global ischemia. HFD-fed mice receiving Calanus oil or exenatide showed less intra-abdominal fat deposition than mice receiving nonsupplemented HFD. Both treatments prevented the HFD-induced decline in myocardial glucose oxidation. Somewhat surprising, recovery of LV function was apparently better in hearts from mice fed nonsupplemented HFD relative to hearts from mice fed normal chow. More importantly however, postischemic recovery of hearts from mice receiving HFD with Calanus oil was superior to that of mice receiving nonsupplemented HFD and mice receiving HFD with exenatide, as expressed by better pressure development, contractility, and relaxation properties. In summary, dietary Calanus oil and administration of exenatide counteracted obesity-induced derangements of myocardial metabolism. Calanus oil also protected the heart from ischemia, which could have implications for the prevention of obesity-related cardiac disease. NEW & NOTEWORTHY This article describes for the first time that dietary supplementation with a low amount (2%) of a novel marine oil (Calanus oil) in mice is able to prevent the overreliance of fatty acid oxidation for energy production during obesity. The same effect was observed with infusion of the incretin mimetic, exanatide. The improvement in myocardial metabolism in Calanus oil-treated mice was accompanied by a significantly better recovery of cardiac performance following ischemia-reperfusion. Listen to this article’s corresponding podcast at https://ajpheart.podbean.com/e/dietary-calanus-oil-energy-metabolism-and-cardiac-function/ .

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Clinical validation of three cardiovascular magnetic resonance techniques to measure strain and torsion in patients with suspected coronary artery disease

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/s12968-020-00684-2 ◽

2020 ◽

Vol 22 (1) ◽

Author(s):

Johan Kihlberg ◽

Vikas Gupta ◽

Henrik Haraldsson ◽

Andreas Sigfridsson ◽

Sebastian I. Sarvari ◽

...

Keyword(s):

Coronary Artery Disease ◽

Cardiovascular Magnetic Resonance ◽

Coronary Artery ◽

Magnetic Resonance ◽

Circumferential Strain ◽

Myocardial Strain ◽

Radial Strain ◽

Left Ventricular ◽

Operating Characteristics ◽

Artery Disease

Abstract Background Several cardiovascular magnetic resonance (CMR) techniques can measure myocardial strain and torsion with high accuracy. The purpose of this study was to compare displacement encoding with stimulated echoes (DENSE), tagging and feature tracking (FT) for measuring circumferential and radial myocardial strain and myocardial torsion in order to assess myocardial function and infarct scar burden both at a global and at a segmental level. Method 116 patients with a high likelihood of coronary artery disease (European SCORE > 15%) underwent CMR examination including cine images, tagging, DENSE and late gadolinium enhancement (LGE) in the short axis direction. In total, 97 patients had signs of myocardial disease and 19 had no abnormalities in terms of left ventricular (LV) wall mass index, LV ejection fraction, wall motion, LGE or a history of myocardial infarction. Thirty-four patients had myocardial infarct scar with a transmural LGE extent (transmurality) that exceeded 50% of the wall thickness in at least one segment. Global circumferential strain (GCS) and global radial strain (GRS) was analyzed using FT of cine loops, deformation of tag lines or DENSE displacement. Results DENSE and tagging both showed high sensitivity (82% and 71%) at a specificity of 80% for the detection of segments with > 50% LGE transmurality, and receiver operating characteristics (ROC) analysis showed significantly higher area under the curve-values (AUC) for DENSE (0.87) than for tagging (0.83, p < 0.001) and FT (0.66, p = 0.003). GCS correlated with global LGE when determined with DENSE (r = 0.41), tagging (r = 0.37) and FT (r = 0.15). GRS had a low but significant negative correlation with LGE; DENSE r = − 0.10, FT r = − 0.07 and tagging r = − 0.16. Torsion from DENSE and tagging had a weak correlation (− 0.20 and − 0.22 respectively) with global LGE. Conclusion Circumferential strain from DENSE detected segments with > 50% scar with a higher AUC than strain determined from tagging and FT at a segmental level. GCS and torsion computed from DENSE and tagging showed similar correlation with global scar size, while when computed from FT, the correlation was lower.

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