Left Ventricular Volume Measurements Research Articles

405 Automated Assessment Of Global Left Ventricular Function And Mass By Cine Computed Tomography Angiography

Introduction: Cine Cardiovascular Computed Tomography Angiography (CTA) provides exceptional spatial resolution for the assessment of left ventricular (LV) contractile function. However, reliable measurement of LV volume and myocardial mass (LVM) over different cardiac phases imposes a major burden for manual delineation. We propose an artificial intelligent (AI) system to automatically segment the LV and LVM from Cine CTA images and compare the results with Cine Cardiovascular Magnetic Resonance (CMR) measurements.

Assessment of subclinical left ventricular systolic dysfunction and structural changes in patients with chronic obstructive pulmonary disease.

Patients with chronic obstructive pulmonary disease (COPD) can develop left ventricular (LV) systolic dysfunction and geometric changes due to several reasons. To investigate subclinical LV systolic dysfunction and structural features in patients with COPD, and its correlation with the severity of airway obstruction, identified by GOLD classification. We studied 52 patients with COPD and 29 age and sex-matched controls, without any cardiac disease. In addition to conventional echocardiographic evaluation speckle tracking echocardiography (STE)-based strain imaging were performed to analyse sub-clinical LV systolic dysfunction. Also LV volumes were measured by using three-dimensional real time echocardiography (3DRTE). All patients underwent spirometry. Conventional echocardiographic parameters (LV wall thickness and diameters, LV EF) and LV volume measurements were similar between the groups. LV global longitudinal peak systolic strain (-14.76 ± 2.69% to -20.27 ± 1.41%, P < 0.001) and strain rate (0.75 ± 0.25 1/s to 1.31 ± 0.41 1/s, P < 0.001) were significantly impaired in patients, compared to controls demonstrating sub-clinical ventricular systolic dysfunction. Significant positive correlation was obtained between LV strain/strain rate and spirometry parameters (FEV1, FEV%, FEV1/FVC, PEF%) (r = 0.78/0.68, P < 0.001; r = 0.83/0.70, P < 0.001); r = 0.74/0.55, P < 0.001; r = 0.72/0.65, P < 0.001 respectively). In addition, there was significant negative correlation between LV strain/strain rate and GOLD classification (r = -0.80/ -0.69, P < 0.001 respectively). Subclinical LV systolic dysfunction can occur in COPD patients despite normal EF. STE is a technique that provides additional information for detailed evaluation of subtle changes in LV myocardial contractility, significantly associated with the severity of the disease in COPD patients.

A Lumped Two-Compartment Model for Simulation of Ventricular Pump and Tissue Mechanics in Ischemic Heart Disease.

Introduction: Computational modeling of cardiac mechanics and hemodynamics in ischemic heart disease (IHD) is important for a better understanding of the complex relations between ischemia-induced heterogeneity of myocardial tissue properties, regional tissue mechanics, and hemodynamic pump function. We validated and applied a lumped two-compartment modeling approach for IHD integrated into the CircAdapt model of the human heart and circulation. Methods: Ischemic contractile dysfunction was simulated by subdividing a left ventricular (LV) wall segment into a hypothetical contractile and noncontractile compartment, and dysfunction severity was determined by the noncontractile volume fraction (). Myocardial stiffness was determined by the zero-passive stress length ( and nonlinearity () of the passive stress-sarcomere length relation of the noncontractile compartment. Simulated end-systolic pressure volume relations (ESPVRs) for 20% acute ischemia were qualitatively compared between a two- and one-compartment simulation, and parameters of the two-compartment model were tuned to previously published canine data of regional myocardial deformation during acute and prolonged ischemia and reperfusion. In six patients with myocardial infarction (MI), the was automatically estimated using the echocardiographic LV strain and volume measurements obtained acutely and 6 months after MI. Estimated segmental values at the baseline and 6-month follow-up were compared with percentage late gadolinium enhancement (LGE) at 6-month follow-up. Results: Simulation of 20% of shifted the ESPVR rightward while moderately reducing the slope, while a one-compartment simulation caused a leftward shift with severe reduction in the slope. Through tuning of the , , and , it was found that manipulation of the alone reproduced the deformation during acute ischemia and reperfusion, while additional manipulations of and were required to reproduce deformation during prolonged ischemia and reperfusion. Out of all segments with LGE>25% at the follow-up, the majority (68%) had higher estimated at the baseline than at the follow-up. Furthermore, the baseline correlated better with percentage LGE than did at the follow-up. Conclusion: We successfully used a two-compartment model for simulation of the ventricular pump and tissue mechanics in IHD. Patient-specific optimizations using regional myocardial deformation estimated the in a small cohort of MI patients in the acute and chronic phase after MI, while estimated values closely approximated the extent of the myocardial scar at the follow-up. In future studies, this approach can facilitate deformation imaging–based estimation of myocardial tissue properties in patients with cardiovascular diseases.

Comparison of left ventricular subclinical systolic dysfunction between hemodialysis patients and renal transplant recipients using real time three-dimensional echocardiography.

The relationship between chronic kidney disease and development of heart failure is a well-known clinical entity. Systolic dyssynchrony index (SDI_16) is a new diagnostic tool for detection of subclinical left ventricular (LV) systolic dysfunction by using three-dimensional echocardiography (3DE). We aimed to investigate this parameter in patients with end-stage renal disease who were receiving hemodialysis and patients with renal transplant compared to healthy control subjects. Forty-five hemodialysis patients, 45 patients with renal transplant and 45 age-sex matched healthy control subjects included in the study. All participants were evaluated with 3DE in the interdialytic phase for measurement of LV volumes, ejection fraction and SDI_16 parameter. Both LV diastolic and systolic volumes were significantly higher in hemodialysis group compared to renal transplant group and healthy controls, but this finding did not translate to a statistically significant difference for LVEF measurements between groups (58.71 ± 3.53 vs. 57.17 ± 2.97 vs. 59.23 ± 3.26, p = .16 for renal transplant and hemodialysis and healthy control groups, respectively). Mean value of SDI_16 parameters was significantly higher in hemodialysis group compared to renal transplant group (7.93 ± 2.50 vs. 3.72 ± 1.71, p < .001) and healthy controls (7.93 ± 2.50 vs. 3.00 ± .99, p < .001); whereas, it was similar between renal transplant group and control subjects (3.72 ± 1.71 vs. 3.00 ± .99, p = .10). SDI_16 was significantly higher in hemodialysis patients compared to patients with renal transplant and healthy controls.

Physiological trend analysis of a novel cardio-pulmonary model during a preload reduction manoeuvre

Background and objective: Mechanical ventilation causes adverse effects on the cardiovascular system. However, the exact nature of the effects on haemodynamic parameters is not fully understood. A recently developed cardio-vascular system model which incorporates cardio-pulmonary interactions is compared to the original 3-chamber cardiovascular model to investigate the exact effects of mechanical ventilation on haemodynamic parameters and to assess the trade-off of model complexity and model reliability between the 2 models.Methods: Both the cardio-pulmonary and three chamber models are used to identify cardiovascular system parameters from aortic pressure, left ventricular volume, airway flow and airway pressure measurements from 4 pigs during a preload reduction manoeuvre. Outputs and parameter estimations from both models are contrasted to assess the relative performance of each model and to further investigate the effects of mechanical ventilation on haemodynamic parameters.Results: Both models tracked measurements accurately as expected. There was no identifiable increase in error from the added complexity of the cardio-pulmonary model, with both models having a mean average error below 0.5% for all pigs. Identified left ventricle and vena cava elastances of the 3-chamber model was found to diverge exponentially with PEEP from identified left ventricle and vena cava elastances of the cardio-pulmonary model. The r2 of the fit for each pig ranged from 0.888 to 0.998 for left ventricle elastance divergence and from 0.905 to 0.999 for vena cava elastance divergence. All other identified parameters showed no significant difference between models.Conclusions: Despite the increase in model complexity, there was no loss in the cardio-pulmonary model’s ability to accurately estimate haemodynamic parameters and reproduce system dynamics. Furthermore, the cardio-pulmonary model was able to demonstrate how mechanical ventilation affected parameter estimations as PEEP was increased. The 3-chamber model was shown to produce parameter estimations which diverged exponentially with PEEP, while the cardiopulmonary model estimations remained more stable, suggesting its ability to produce more physiologically accurate parameter estimations under higher PEEP conditions.

Normalisation of diabetic heart pump function at decreased functional load.

Aim To study left ventricular (LV) hemodynamics in presence of decreased blood inflow to the heart as well as changes in myocardial content of energy metabolites in diabetic rats.Material and methods Diabetic cardiomyopathy is characterized by impaired heart contractility and by transition of cardiomyocyte energy metabolism fatty acids exclusively as a source of energy. This reduces the efficiency of energy utilization and increases the heart vulnerability to hypoxia. This study was performed on rats with type 1 diabetes mellitus induced by administration of streptozotocin (60 mg/kg). The LV pump function was studied with a catheter that allows simultaneous measurement of LV pressure and volume in each cardiac cycle.Results Blood glucose was approximately sixfold increased at 2 weeks. Heart failure was detected with decreases in ejection fraction by 27%, minute volume by 39%, and stroke work by 41%. Systolic dysfunction was based on a decrease in LV peak ejection velocity by more than 50%. Furthermore, the LV developed pressure and contractility index were within the normal range, while 1.5 times increased arterial stiffness was the factor that hampered ejection. The sum of adenine nucleotides was decreased by 21%, the ATP content was decreased by 29%, and also creatine phosphate formation was reduced in the myocardium of diabetic rats. Lactate content in the diabetic myocardium was increased almost threefold, which indicated mobilization of aerobic glycolysis. With the reduced preload, equal diastolic volume (0.3 ml), and equal blood pressure (60 mm Hg), the diabetic heart pump function did not differ from the control.Conclusion In type 1 diabetes mellitus, decreases in functional load and oxygen consumption normalize the myocardial pump function with disturbed energy metabolism.

Assessment of left ventricular systolic function using two- and three-dimensional speckle tracking echocardiography among healthy preschool-age pediatric children

BackgroundAccurate measurements of left ventricular (LV) volumes and function are important in the management of patients with various cardiac abnormalities. Two-dimensional (2D) speckle tracking echocardiography (STE) is shown to be accurate in detecting subclinical myocardial dysfunction when most of the conventional echocardiography parameters were normal. Three-dimensional (3D) echocardiography is a new noninvasive imaging technique that has been shown to be accurate in determining cardiac volume and performance. Establishment of normal range values of 3D STE over a different range of ages is crucial before applying this recent technology in clinical applications. This study aimed to assess feasibility of 3D LV STE and establish normal values for the LV systolic function among healthy Egyptian preschool-age pediatric population using 2D and 3D STE.ResultsA total of 200 subjects (95%) met the criteria for 2DSTE analysis, 10 were excluded from the 2D analysis and 180 subjects (85%) met the criteria for 3D STE analysis. Regarding the 2D STE GLS, the mean was -22.1345 ± 2.166%, GCS was f -19.02 ± 1.23%, and GRS was 42.25 ± 2.35%. There was a strongly positive significant correlation between age and 2D values of GLS (P = 0.001). The GCS showed a weakly positive nonsignificant correlation with age (P = 0.28), while GRS showed a strongly negative significant correlation with age (P = 0.001). Regarding the 3D STE data, GLS mean was -20.48 ± 1.526%, GCS mean was -13.90 ± 2.05%, while GRS mean was 47.21 ± 2.382%. 3D GLS values had a strongly positive significant correlation with age (P = 0.001). While GCS showed a weakly positive nonsignificant correlation (P = 0.955), GRS showed a strongly negative significant correlation (P = 0.001). Linear correlation analysis of 2D and 3D values of strain showed that GLS had a strongly positive significant correlation (P = 0.001), while GCS showed a weakly positive nonsignificant correlation (P = 0.161) and GRS showed a strongly positive significant correlation (P = 0.001).Conclusions3D global strain analysis using the 3D STE is feasible in the preschool-age pediatric population. Results were almost concordant with previous observations in most of the values except for GCS, especially 3D values which could be attributed to different vendor system used and different ethnicity. Further studies are required to reinforce these data using the GE vendor machine.

Strain-based characterization of electromechanical tissue properties using patient-specific simulation of dyssynchronous hearts: a pilot study

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Dutch Heart Foundation (ERA-CVD JTC2018 grant 2018T094; Dr. Dekker Program grant 2015T082 to J.L.) and the Netherlands Organisation for Scientific Research (NWO- ZonMw, VIDI grant 016.176.340 to J.L.) Background/Introduction Interpretation of regional strain patterns in patients with failing hearts is often challenging due to presence of different underlying tissue abnormalities, including electrical conduction delay and myocardial infarction (MI). Purpose To test whether an automatic strain-based computer simulation algorithm can differentiate between electrical and ischemic contractile dysfunction in patients with mechanical dyssynchrony. Methods Three heart failure patients with reduced left ventricular ejection fraction (33 ± 3%) and wide QRS (160 ± 7ms, LBBB morphology) were retrospectively included, two with and one without MI. Longitudinal strain patterns obtained in 18 myocardial segments using speckle tracking echocardiography (STE) and left ventricular (LV) volume measurements were used as an input to the patient-specific simulation algorithm, which automatically optimizes a set of global and regional myocardial tissue parameters such that the regional strain patterns and global volumes simulated by the CircAdapt model of the human heart and circulation were similar to the strains and volumes measured in the patients. As output, the patient-specific simulations revealed onset time of mechanical activation (relative to first activated segment) and relative severity of contractile dysfunction in all 18 segments. We compared predicted mechanical activation delays and segmental contractile dysfunction values with independent measurements of QRS width and transmurality of late gadolinium enhancement (LGE), respectively. Results The model was able to reproduce the dyssynchronous regional strain patterns as measured in the patients (Figure 1: representative example). In all patients, significant septal—to-lateral wall mechanical activation delays (33-55ms) were predicted (Figure 2: blue bullseye plot of same patient used for figure 1), matching the presence of electrical activation delays on the patient’s ECGs (i.e. wide QRS and LBBB morphology). Furthermore, all simulations predicted a global loss of contractile dysfunction, matching the low ejection fractions reported in those patients. The simulations of the two patients with MI predicted more severe contractile dysfunction (&amp;gt;60%) in the regions with transmural LGE (Figure 2: red bullseye plot versus gold standard LGE-MRI image of same patient used for figure 1). Conclusion This pilot study demonstrated the ability of an automatic patient-specific simulation algorithm to differentiate between electrical and ischemic myocardial disease substrates in heart failure patients with electrical conduction abnormalities with and without MI. Future studies will investigate whether this computer algorithm can improve diagnosis of patients with mechanical dyssynchrony. Abstract Figure 1 Abstract Figure 2

Semi-automated left ventricular endocardial detection versus hand-tracing in the measurement of left ventricular volumes and ejection fraction in daily clinical practice

Abstract Background The common method of assessing left ventricle (LV) volumes and ejection fraction (EF) is hand-tracing Biplane Simpson method. Alternatively, ultrasound vendors offer different semi-automated LV endocardial border detection software with anatomical intelligence to assess LV volumes and EF. By using speckle-tracking technique, this software tracks the LV endocardium throughout the cardiac cycle and computes the LV volumes in every image frame using the disk summation method from which a volume-curve is generated, and the EF is calculated using the maximum and minimum volumes obtained. Data on the performance of this method in comparison with the hand-tracing Biplane Simpson method in daily clinical practice is scarce. Purpose To determine the accuracy of LV volumes and EF using semi-automated LV endocardial detection tracing, and to compare the reproducibility of this method with the hand-tracing Biplane Simpson method, among operators with varying level of experience in echocardiography. Methods This was a single center retrospective observational study, conducted in year 2020. 127 patients, aged &amp;gt;18 years, who underwent clinically indicated transthoracic echocardiography were recruited. The echocardiographic images were analyzed independently in a blinded fashion by 3 operators – a sonographer, a fellow-in-training and a cardiologist specialized in echocardiography. The LV volumes and EF were first measured using hand-tracing Biplane Simpson method, then repeated using semi-automated tracing at a different time and the operator were blinded to the initial hand-tracing measurements. Results The mean age of patients was 50±16 years, 35.4% were male, mean body surface area was 1.62±0.18m2, 92.1% were in sinus rhythm, and 61.4% had good acoustic window. Table 1 shows the LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF, measured using different method, by the 3 operators. There were excellent correlation and agreement between semi-automated tracing measurements and hand-tracing measurements of LV EDV (r=0.985, LOA [mean ± 1.96 SD] 16.9 ml, ICC 0.991), ESV (r=0.990, LOA 12.7 ml, ICC 0.994) and EF (r=0.962, LOA 7.43%, ICC 0.967) by experienced cardiologist. The limit of agreement (LOA) between cardiologist and sonographer for semi-automated tracing measurement of LV EDV, ESV and EF were 29.13 ml, 19.74 ml and 9.25% respectively, which was comparable with that of hand-tracing measurement. The agreement between cardiologist and fellow-in-training for semi-automated tracing measurement of LV volumes and EF was slightly better than hand-tracing method, with a LOA of 25.60 ml, 17.48 ml and 7.08%, for EDV, ESV and EF respectively (Table 2). Conclusion In daily clinical practice, measurement of LV volumes and EF using semi-automated LV endocardial tracing method is accurate and demonstrates comparable reproducibility with hand-tracing Biplane Simpson method among operators with different level of experience in echocardiography. Funding Acknowledgement Type of funding sources: None.

Myocardial Function in Premenopausal Women Treated With Ovarian Function Suppression and an Aromatase Inhibitor

BackgroundPremenopausal women with high-risk hormone receptor (HR)-positive breast cancer often receive ovarian function suppression (OFS) with aromatase inhibitor therapy; however, abrupt menopause induction, together with further decrements in estrogen exposure through aromatase inhibition, may affect cardiovascular microcirculatory function. We examined adenosine-induced changes in left ventricular (LV) myocardial T1, a potential subclinical marker of LV microcirculatory function in premenopausal women undergoing treatment for breast cancer.MethodsTwenty-one premenopausal women (14 with HR-positive breast cancer receiving OFS with an aromatase inhibitor and 7 comparator women with triple-negative breast cancer [TNBC] who had completed primary systemic therapy) underwent serial resting and adenosine cardiovascular magnetic resonance imaging measurements of LV myocardial T1 and LV volumes, mass, and ejection fraction. All statistical tests were 2-sided.ResultsAfter a median of 4.0 months (range = 3.1-5.7 months), the stress to resting ratio of LV myocardial T1 declined in women with HR-positive breast cancer (−1.3%, 95% confidence interval [CI] = −3.4% to 0.7%) relative to those with TNBC (3.2%, 95% CI = −1.2% to 7.6%, P = .02). After accounting for age, LV stroke volume, LV ejection fraction, diastolic blood pressure, and breast cancer subtype women with HR-positive breast cancer experienced a blunted T1 response after adenosine relative to women with TNBC (difference = −4.7%, 95% CI = −7.3% to −2.1%, Pdifference = .002).ConclusionsOver the brief interval examined, women with HR-positive breast cancer receiving OFS with an aromatase inhibitor experienced reductions in adenosine-associated changes in LV myocardial T1 relative to women who received nonhormonal therapy for TNBC. These findings suggest a possible adverse impact on LV myocardial microcirculatory function in premenopausal women with breast cancer receiving hormone deprivation therapy.

Quantitative Analyses of the Left Ventricle Volume and Cardiac Function in Normal and Infarcted Yucatan Minipigs

(1) Background: The accuracy of the left ventricular volume (LVV) and contractility measurements with cardiac magnetic resonance imaging (CMRI) is decreased if the papillary muscles are abnormally enlarged, such as in hypertrophic cardiomyopathy in human patients or in pig models of human diseases. The purpose of this work was to establish the best method of LVV quantification with CMRI in pigs. (2) Methods: The LVV in 29 Yucatan minipig hearts was measured using two different techniques: the “standard method”, which uses smooth contouring along the endocardial surface and adds the papillary volume to the ventricular cavity volume, and the “detailed method”, which traces the papillary muscles and trabeculations and adds them to the ventricular mass. (3) Results: Papillary muscles add 21% to the LV mass in normal and infarcted hearts of Yucatan minipigs. The inclusion or exclusion of these from the CMRI analysis significantly affected the study results. In the normal pig hearts, the biggest differences were found in measurements of the LVV, ejection fraction (EF), LV mass and indices derived from the LV mass (p < 0.001). The EF measurement in the normal pig heart was 11% higher with the detailed method, and 19% higher in the infarcted pig hearts (p < 0.0001). The detailed method of endocardium tracing with CMRI closely represented the LV mass measured ex vivo. (4) Conclusions: The detailed method, which accounts for the large volume of the papillary muscles in the pig heart, provides better accuracy and interobserver consistency in the assessment of LV mass and ejection fraction, and might therefore be preferable for these analyses.

The impact of mild ischemic mitral regurgitation in the occurrence of congestive heart failure

Ischemic mitral regurgitation (IMR) is a common complication of myocardial infarction, leading to left ventricular (LV) dysfunction and remodeling. Its presence is associated with an increased risk for death and heart failure. The aim of this study was to evaluate the impact of a mild degree (effective regurgitant orifice area < 20 mm 2 ) of IMR on heart failure (HF). This is a retrospective, study including 210 patients who had been hospitalized in a cardiology intensive care unit for myocardial infarction from September 2018 to March 2020, 36 patients with mild IMR were compared to 40 patients without IMR (controls), measuring LV volumes, ejection-fraction, and the degree of mitral regurgitation and incidence of HF events. The main age was 59.3 ± 7.02 sex ratio: 2.86 (74.1% male, 25.9% female) 32.3% of patients had de novo heart failure of which 29.2% with mild IMR. Patients with IMR had a significantly higher incidence of HF than controls (72% vs. 34%, P = 0.001), a significant increase in LV end-diastolic and end-systolic volumes, ( P = 0.004) and lower ejection-fractions ( P = 0.0002). The culprit artery was left anterior descending artery in 54.4%. The presence of IMR, even mild in degree, has an impact on the progression of the post-infarction ventricular dysfunction and a higher rate of HF.

To Vent or Not to Vent: A Loaded Question During Venoarterial Extracorporeal Membrane Oxygenation Support for Cardiogenic Shock

To Vent or Not to Vent: A Loaded Question During Venoarterial Extracorporeal Membrane Oxygenation Support for Cardiogenic Shock

Compensatory Changes of the Diastole under Conditions of Inflow Restriction to the Heart.

This work was designed to study changes in the mechanical properties of rat myocardium during short-term (2-3 sec) compression of the lower vena cava. A catheter was inserted into the left ventricle, allowing simultaneous measurement of left-ventricular volume and pressure. The decrease in the left-ventricular end-diastolic volume caused by inflow restriction was accompanied by less pronounced decrease in the left-ventricular stroke volume and maximum rate of left-ventricular pressure development. This was coincided with accelerated relaxation and deeper fall of the minimum left-ventricular diastolic pressure. The lower was left-ventricular end-systolic volume, the greater was the degree of these changes. It is assumed that the "restoring force" that naturally appears under conditions of low filling of the left ventricle is determined by elastic N2B part of the titin molecule that is compressed during strong shortening of myofibrils and accelerates their return to the previous length during relaxation. As a result of better filling of the left ventricle, the heart can maintain left-ventricular stroke volume at the appropriate level.

Left ventricle assessment by three-dimensional HeartModel software in different types of mitral valve prolapse (Barlow's disease and fibroelastic deficiency) with severe mitral regurgitation.

Mitral valve prolapse (MVP) is the most common cause of isolated mitral regurgitation (MR) requiring surgical repair. Therapeutic interventions should be considered before irreversible left ventricular (LV) dysfunction in asymptomatic patients. Measurement of LV volume and function is very important. Because of two-dimensional (2D) echocardiography limitations, three-dimensional (3D) measurement is preferred on the strength of its speed, accuracy, and reproducibility, which are comparable with those of magnetic resonance imaging (MRI). This study was conducted between April 2018 and February 2019 on 50 patients with different MVP types and severe MR scheduled for valve surgery at Rajaie Cardiovascular Research Center, Tehran, Iran, with the aid of the HeartModelAnatomical intelligence (A.I.) (EPIQ 7: new 3D software) for measurement of LV volume indices and function. Patients with the Barlow syndrome had a greater drop in LV ejection fraction (LVEF) than those with fibroelastic deficiency (FED) (57.05% ± 6.00% vs. 65.00% ± 4.08%; P = 0.001). LV volume was larger in patients with flail mitral valve (MV) than in those with non-flail MV (165 cc vs. 118 cc; P = 0.001). LVEF declined more in patients with the involvement of both leaflets than in those with the involvement of the anterior leaflet alone (56.00% ± 7.10% vs. 57.70% ± 4.30%; P = 0.021). The LVEF drop was more remarkable in patients with the Barlow syndrome (both flail and non-flail MV) than in those with FED. It is, therefore, advisable that such patients be monitored more meticulously via the 3D HeartModelA.I. method in terms of LVEF and LV size to prevent irreversible effects on LV function and to reduce mortality.

Global longitudinal strain in patients with severe aortic stenosis: a comparison between cardiac magnetic resonance imaging feature tracking and speckle tracking echocardiography

Abstract Funding Acknowledgements Type of funding sources: None. Background Global longitudinal strain (GLS) by echocardiography is a sensitive method for measuring left ventricular (LV) function, and of better prognostic value in valvular heart disease than ejection fraction (EF). Cardiac magnetic resonance imaging (CMR) is the most accurate method for measuring LV volume and EF, but GLS has not been possible to measure by CMR until recently. Purpose This study compares GLS obtained by CMR and echocardiography in patients with severe aortic valve stenosis. Normal values for GLS by CMR are reported as well. Methods GLS was measured in 32 patients with severe aortic valve stenosis with speckle tracking echocardiography, using GE Vivid E95 (n = 15) and Philips EPIQ (n = 17) ultrasound machines, as well as with CMR (Avanto 1.5T FIT, Siemens Medical Solutions). For normal values, GLS was measured by CMR in 9 healthy controls. Endo- and epicardial borders of two, three and four chamber cine images were traced for CMR GLS using dedicated software (Qstrain 2.0, Medis, NL). Both CMR and Vivid E95 measured midmyocardial strain, whereas the EPIQ AutoStrain method measures endomyocardial strain. Absolute values of GLS are reported. Pearson correlation coefficient was calculated and paired Student’s t-test was used for comparisons. Results A significant correlation (r = 0.45, p = 0.01) was found between echocardiographic and CMR GLS (Figure). GLS by Vivid E95 had a very good correlation with CMR GLS (r = 0.84, p = 0.0001), whereas GLS by Philips EPIQ did not correlate significantly (r = 0.14, p = 0.01). In patients with aortic stenosis and healthy controls, the average GLS by CMR was 18.3 ± 3% and 20.9 ± 2% respectively. The average GLS by CMR was comparable to that obtained by GE Vivid E95 (17.3 ± 4% vs. 17.2 ± 3%, p = 0.92), and higher than by Philips EPIQ (19.2 ± 2% vs. 15.4 ± 2%, p &amp;lt; 0.0001). Conclusion This study shows that GLS by CMR is feasible and correlates with GLS obtained by echocardiography, especially when quantifying midmyocardial strain. Echocardiographic GLS values based on endomyocardial strain were lower. Patient characteristics Age 75 ± 14 y NYHA 1 1 (3 %) NYHA 2 20 (67 %) NYHA 3 8 (27 %) NYHA 4 1 (3 %) CMR EF 66 ± 8 % AVA 0.7 ± 0.2 cm&amp;sup2; NYHA = NYHA class of symptoms, EF = ejection fraction by CMR, AVA = aortic valve area by echocardiography Abstract Figure. GLS by CMR vs. Echocardiography

Comparison between cardiac magnetic resonance and speckle-tracking echocardiography in prediction of cardiac resynchronization therapy outcomes

Background Cardiac resynchronization therapy (CRT) improves quality of life, exercise tolerance, and myocardial function in a considerable number of patients with heart failure (HF) and left bundle branch block. In addition, CRT decreases HF hospitalizations and overall mortality. However, structural, morbidity, and mortality improvements after CRT rate between 40 and 60%.Objective To compare the role of the cardiac magnetic resonance (CMR) and speckle-tracking echocardiography (STE) in expectation of response to CRT.Patients and methods We investigated the predictors of CRT response using CMR measurement of left ventricular (LV) volumes and function, CMR-derived mechanical dyssynchrony, scar percentage, and its relation to the site of LV lead implantation, in comparison with STE in prediction of CRT outcomes.Results A total of 35 patients with HF planned for CRT were included. Echocardiography was used to define the response to CRT (15% reduction in LV end-systolic volume 6 months after implantation). At follow-up, 18 (51.43%) patients were categorized as responders. Echocardiographic speckle-tracking radial strain analysis showed a significant LV dyssynchrony in responders versus nonresponders (radial mid-anteroseptal and posterior wall delays were 245.1 ms and 80.7 ms, respectively) (P<0.0001). LV radial dyssynchrony, as measured by CMR-feature tracking, was significantly higher in responders versus nonresponders (mean of SDt-16 of radial strain were 232.7 ms vs. 180.4 ms, P<0.0001), and median of radial mid-anteroseptal-to-inferolateral wall delay was 375 vs. 125.4 ms, P<0.0001). Late contrast-enhanced CMR was performed for scar assessment. It was noticed that scar percentage of LV mass was much higher in nonresponders (median 6.2 vs. 0%) (P=0.005).Conclusion CMR imaging offers the unique opportunity to predict the CRT outcomes by measurement of LV volumes, LV mechanical dyssynchrony (that well correlated with that of STE), and the total scar percentage and distribution in a single examination.

Automated Measurements of Left Ventricular Ejection Fraction and Volumes Using the EchoPAC System

Automated Measurements of Left Ventricular Ejection Fraction and Volumes Using the EchoPAC System

Quantitative assessment of left ventricular volume and function by transthoracic and transesophageal echocardiography, ultrasound velocity dilution, and gated magnetic resonance imaging in healthy foals.

To compare measurements of left ventricular volume and function derived from 2-D transthoracic echocardiography (2DE), transesophageal echocardiography (TEE), and the ultrasound velocity dilution cardiac output method (UDCO) with those derived from cardiac MRI (cMRI) in healthy neonatal foals. 6 healthy 1-week-old Standardbred foals. Foals were anesthetized and underwent 2DE, TEE, and cMRI; UDCO was performed simultaneously with 2DE. Images acquired by 2DE included the right parasternal 4-chamber (R4CH), left apical 4- and 2-chamber (biplane), and right parasternal short-axis M-mode (M-mode) views. The longitudinal 4-chamber view was obtained by TEE. Measurements assessed included left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), ejection fraction, stroke volume (LVSV), cardiac output (CO), and cardiac index (CI). Bland-Altman analyses were used to compare measurements derived from biplane, R4CH, and M-mode images and UDCO with cMRI-derived measurements. Repeatability of measurements calculated by 3 independent reviewers was assessed by the intraclass correlation coefficient. Compared with cMRI, all 2DE and TEE modalities underestimated LVEDV and LVESV and overestimated ejection fraction, CO, and CI. The LVSV was underestimated by the biplane, R4CH, and TEE modalities and overestimated by UDCO and M-mode methods. However, the R4CH-derived LVSV, CO, and CI were clinically comparable to cMRI-derived measures. Repeatability was good to excellent for measures derived from the biplane, R4CH, M-mode, UDCO, and cMRI methods and poor for TEE-derived measures. All assessed modalities yielded clinically acceptable measurements of LVEDV, LVESV, and function, but those measurements should not be used interchangeably when monitoring patient progress.

Abstract 14082: The Effect of Diagnostic Ultrasound Mediated High Mechanical Impulses on Cardiac Output During an Ultrasound Enhancing Agent Infusion

Introduction: Diagnostic ultrasound high mechanical index (MI) impulses are used during an ultrasound enhancing agent (UEA) infusion to improve endocardial border resolution and study myocardial perfusion. They have also been shown to cause endothelial shear, resulting in prolonged increases in ATP release and augment microvascular flow. The potential for these high MI impulses to alter cardiac output (CO) are unknown. Hypothesis: To study the impact of high MI impulses on CO Methods: Fifty one patients (mean age 63±15 years; 41% female) referred for contrast echocardiography underwent very low MI imaging with intermittent high MI impulses (1.6-1.7 Megahertz) in three different apical windows during either a Definity (Lantheus Medical) or Lumason (Bracco Diagnostics) infusion or bolus. CO was determined from Doppler measurements of left ventricular outflow tract stroke volume and heart rate. Mean contrast enhanced biplane left ventricular ejection fraction (LVEF) was 53±15%; (range 10-75%). CO from baseline without contrast (COwoC) and baseline after contrast (COwC) before high MI impulses were compared to CO after contrast and after high MI impulses (COaHMI). All CO measurements were made by an independent reviewer blinded to time of measurement (before or after high MI impulses). Results: Although heart rate did not change before and after intermittent high MI impulse administration, COaHMI increased significantly when compared to COwoC and COwC (p&lt; 0.001 for both comparisons; Figure). In nine patients (18%), CO increased by more than 20%. In patients with LVEF &lt; 40% COwC was 2.4±0.8 liters per minute (LPM) and COaHMI increased to 2.7± 0.8 LPM (p=0001). In patients with LVEF≥40%, COwC was 3.4±1.06 LPM while COaHMI increased to 3.8± 1.2 LPM (p=0.00001). Conclusions: Application of diagnostic guided high MI impulses during a commercially available microbubble infusion significantly increases CO irrespective of underlying left ventricular systolic function.