Left Ventricle Sphericity Research Articles

Pressure-dimension index and left ventricular sphericity index following HeartMate II and HeartMate 3 implantation.

This study aimed to compare the changes in the left ventricle (LV) and right ventricle (RV) geometry and performance after the implantation of HeartMate II (HMII) and HeartMate 3 (HM3). In addition, we investigated whether the echocardiographic parameters LV sphericity index (LVSI) and the novel pressure-dimension index (PDI) can predict post-operative right ventricular failure (RVF). Between 2012 and 2020, 46 patients [HMII (n=22) and HM3 (n=24)] met the study's criteria and had echocardiography tests pre-operatively, 6 and 12months post-operatively. The LVSI and PDI were calculated together with the standard LV and RV echocardiographic parameters. The mean follow-up was 24±7months. In both groups, the LV end-diastolic diameter (LVEDD) significantly decreased 12months post-operatively compared with the pre-operative values (HMII: 6.4±1.4cm vs. 5.7±0.9cm, P=0.040; HM3: 6.7±1.3cm vs. 5.5±0.9cm, P<0.01, respectively). RV function 12months post-operatively was better in the HM3 group than in the HMII group, as indicated by a significantly higher RV fractional area change (RVFAC) in the HM3 group than in the HMII group 12months post-operatively (35±12% vs. 26±16%, P=0.039), significantly higher tricuspid annular plane systolic excursion (TAPSE) in the HM3 group 12months post-operatively compared with the HMII group (13.9±1.9mm vs. 12.0±2.1mm, P=0.002), and the tissue Doppler estimated tricuspid annular systolic velocity (TASV) was also significantly higher in the HM3 group 12months post-operatively compared with the HMII group (11.5±2.7mm/s vs. 9.9±1.5mm/s, P=0.020). The LVSI value was significantly higher 12months post-operatively in the HMII group than in the HM3 group (1.2±0.4 vs. 0.8±0.2, P=0.001, respectively), indicating worse geometric changes. The PDI decreased 12months post-operatively in the HM3-group compared with the baseline (3.4±1.4mmHg/cm2 vs. 2.0±0.8mmHg/cm2, P<0.001). In the univariate and multivariate analyses, only the pre-operative PDI was a predictor of post-operative RVF [odds ratio: 3.84 (95% CI: 1.53-18.16, P=0.022)]. The area under the curve for pre-operative PDI was 0.912. The 2year survival was significantly better in the HM3 group (log-rank, P=0.042). The design of HM3 offered better geometrical preservation of the LV and enabled normal PDI values, leading to improved RV function, as indicated by better RVFAC, TAPSE, and TASV values. The use of pre-operative PDI as an additional tool for established risk scores might offer a better pre-operative predictor of RVF.

Evaluation of Left Ventricular Remodelling in Patients with Anterior Myocardial Infarction According to Sphericity and Conicity Indices and their Association with Left Ventricular Function

Background:&#x0D; Following cardiac damage, a complex process known as left ventricular adverse remodelling occurs, which is characterized by alterations in the left ventricle (LV)'s structure, form, and function. The study aims at assessing the significance of the LV sphericity index in quantifying LV geometric alterations, as well as the conicity index's significance in recognizing regional variations in LV geometry and evaluating its relation to the heart's systolic and diastolic function.&#x0D; Methods and Methods: A total of 50 individuals with anterior myocardial infarction (MI) participates in this cross-sectional study. Sphericity (SI) and conicity indices (CI) are calculated using the ratios of the short axis and long axis, and the apical to short LV axis, respectively. Then measurements of the LV's systolic and diastolic functioning are done.&#x0D; Results: The sphericity index and systolic parameters display a statistically significant negative correlation (P&lt;0.05). The conicity index and systolic parameters show a statistically non-significant negative correlation (P&gt;0.05).&#x0D; The relation between CI and SI with LV diastolic parameters reveal a positive correlation, but it was statistically non-significant (p&gt;0.05). Only the left atrial volume index (LAVI) was statistically significant with SI (p&lt;0.05).&#x0D; Conclusion: This study concludes that LV indices are a simple, non-invasive measure of LV remodelling, whether locally by CI or globally by SI, and can reflect the LV's systolic and diastolic performance based on correlation studies.

Extreme cardiac remodelling observed in elite endurance athletes: analysis of myocardial deformation and estimated hemodynamic forces

Abstract Funding Acknowledgements Type of funding sources: None. Background Athletes of endurance disciplines present the highest level of cardiac remodelling often generating concerns for differential diagnosis with cardiomyopathies. In addition to standard morpho-functional evaluation, left ventricle (LV) myocardial deformation (MD) and estimated intra-ventricular hemodynamic forces (HDFs) are emerging diagnostic tools, particularly in heart failure patients. In the athletic population MD data are scarce while HDFs are lacking. Purpose To describe MD and HDFs evaluated by CMR feature-tracking in a cohort of endurance Olympic athletes and to evaluate the possible relationship with LV geometry. Methods A group of endurance Olympic athletes evaluated prior the Olympic games and with unremarkable cardiac pre-participation screening tests was enrolled. All athletes underwent CMR without contrast administration. Cine images were post-processed to evaluate end-diastolic and end-systolic LV volumes, ejection fraction (LVEF), global longitudinal and circumferential strain (GLS and GCS) and estimated HDFs by a dedicated feature-tracking software. HDFs were measured in apex-base (AB) and latero-septal (LS) directions, over the entire cardiac cycle, in systole and diastole. LS/AB ratio was also derived to determine forces distribution. Athletes were divided in subgroups according to the 3D sphericity index (&amp;lt; 40% or 40%). A group of sedentary subjects was enrolled as a control group. Results 109 endurance Olympic athletes (62% male; mean age 26 ± 5 years) and 21 sedentary subjects were enrolled. Athletes with increased sphericity index (≥40%) were 61 (56%) and presented with greater EDV, ESV and lower LVEF compared to those without increased sphericity and controls (Table). No significant differences were found between athletes and controls regarding LV-GLS and GCS. HDFs distribution was not different between groups and even athletes with a more spherical LV shape showed an HDFs diastolic ratio comparable to those of athletes with lower sphericity index and control. Conclusion Although more than half of endurance athletes presented with altered geometry (increased sphericity index), strain parameters and hemodynamic forces were not different from sedentary controls and those athletes without increased sphericity. The use of advanced parameters to evaluate cardiac function could be used as a tool to confirm the benign nature of cardiac adaptation due to intense exercise training.

Sex-differences in associations of LV structure and function measured by echocardiography with long-term risk of mortality and cardiovascular morbidity.

Three-dimensional echocardiography (3DE) measures of the left ventricle (LV) predict outcomes in high risk individuals, but their prognostic value in the general population is unknown. We aimed to establish whether 3DE was associated with mortality and morbidity in a multi-ethnic community-based sample, if associations differed by sex, and explored potential mechanisms explaining sex differences. 922 individuals (69.7 ± 6.2 years; 717 men) from the SABRE study underwent a health examination including echocardiography. Associations between 3DE LV measures (ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), LV remodeling index (LVRI) and LV sphericity index (LVSI), and all-cause mortality and a composite cardiovascular endpoint [comprising new onset (non)fatal coronary heart disease, heart failure hospitalization, new-onset arrhythmias and cardiovascular mortality] were determined using multivariable Cox regression over a median follow-up of 8 years (all-cause mortality) and 7 years (composite cardiovascular endpoint). There were 123 deaths and 151 composite cardiovascular endpoints. Lower EF, higher LV volumes and LVSI were associated with increased all-cause mortality, and higher LV volumes were associated with the composite cardiovascular endpoint independent of potential confounders. Associations between LV volumes, LVRI, LVSI, and mortality differed by sex (p interaction <0.1). In men increased LV volumes and LVSI and decreased LVRI and EF were associated with higher mortality, but associations were null or reversed in women (hazard ratios (95% CI) men vs. women: EDV 1.25 (1.05, 1.48) vs. 0.54 (0.26, 1.10); ESV, 1.36 (1.12, 1.63) vs. 0.59 (0.33, 1.04); LVRI, 0.79 (0.64, 0.96) vs. 1.70 (1.03, 2.80); LVSI, 1.27 (1.05, 1.54) vs. 0.61 (0.32, 1.15); and EF, 0.78 (0.66, 0.93) vs. 1.27 (0.69, 2.33). Similar sex differences were observed for associations with the composite cardiovascular outcome. Adjustment for LV diastolic stiffness and arterial stiffness marginally attenuated these differences. 3DE measures of LV volume and remodeling are associated with all-cause mortality and cardiovascular morbidity; however, some associations differ by sex. Sex-differences in LV remodeling patterns may influence mortality and morbidity risk in the general population.

Deep learning-enabled analysis of medical images identifies cardiac sphericity as an early marker of cardiomyopathy and related outcomes

Quantification of chamber size and systolic function is a fundamental component of cardiac imaging. However, the human heart is a complex structure with significant uncharacterized phenotypic variation beyond traditional metrics of size and function. Examining variation in cardiac shape can add to our ability to understand cardiovascular risk and pathophysiology. We measured the left ventricle (LV) sphericity index (short axis length/long axis length) using deep learning-enabled image segmentation of cardiac magnetic resonance imaging data from the UK Biobank. Subjects with abnormal LV size or systolic function were excluded. The relationship between LV sphericity and cardiomyopathy was assessed using Cox analyses, genome-wide association studies, and two-sample Mendelian randomization. In a cohort of 38,897 subjects, we show that a one standard deviation increase in sphericity index is associated with a 47% increased incidence of cardiomyopathy (hazard ratio [HR]: 1.47, 95% confidence interval [CI]: 1.10-1.98, p= 0.01) and a 20% increased incidence of atrial fibrillation (HR: 1.20, 95% CI: 1.11-1.28, p<0.001), independent of clinical factors and traditional magnetic resonance imaging (MRI) measurements. We identify four loci associated with sphericity at genome-wide significance, and Mendelian randomization supports non-ischemic cardiomyopathy as causal for LV sphericity. Variation in LV sphericity in otherwise normal hearts predicts risk for cardiomyopathy and related outcomes and is caused by non-ischemic cardiomyopathy. This study was supported by grants K99-HL157421 (D.O.) and KL2TR003143 (S.L.C.) from the National Institutes of Health.

Abstract 14453: Deep Learning Enabled Measurement of Cardiac Sphericity Predicts Disease Risk Among Subjects With Normal Left Ventricular Size and Function

Introduction: Cardiac imaging primarily focuses on measurements of chamber size and function. Quantitative assessment of morphology may provide additional prognostic information. Left ventricle (LV) sphericity has been proposed as one metric but has not been studied in large populations and is poorly characterized in patients with normal LVs. We aimed to assess the clinical relevance and genetic drivers of sphericity among individuals with normal LV size and systolic function using deep learning enabled phenotyping of cardiac MRIs. Methods: The study cohort consisted of UK Biobank participants with normal LV ejection fraction, LV end-systolic, and end-diastolic volumes by MRI. A fully convolutional neural network was used to perform image segmentation of cardiac chambers. The main exposure was the LV sphericity index, defined as the ratio of short-axis to long-axis lengths of the smallest rectangle encompassing the LV in a 4-chamber view. Risk for incident outcomes were measured using Cox analysis. Genome-wide association study (GWAS) was performed using HAIL software with standard quality-control. Genetic correlations were measured using linkage-disequilibrium score regression. Causal inference was performed using two-sample Mendelian randomization (MR). Results: We identified 38,897 subjects with normal LV volumes and ejection fraction. Mean age was 55 ± 8, and 54% were female. After adjusting for age, sex, BMI, hypertension, and pulse-rate, a 1 standard deviation increase in sphericity index was associated with increased risk of atrial fibrillation (HR 1.31, 95% CI 1.23-1.38, P &lt;2x10 -16 ) and cardiomyopathy (HR 1.62, 95% CI 1.29-2.02, P 2.4x10 -5 ). GWAS of sphericity index identified 4 loci at genome-wide significance, with 3 candidate genes previously implicated in cardiac development and conduction. Sphericity index showed a genetic correlation with cardiomyopathy ( rg 0.42, P 0.01) but not with atrial fibrillation ( rg 0.04, P 0.5). Bidirectional MR analyses supported cardiomyopathy as being causal for sphericity but not the reverse. Conclusion LV sphericity in subjects with normal size and function is genetically mediated and may reflect subclinical manifestations of cardiomyopathic risk prior to LV remodeling by standard measures.

The Role of Extracellular Matrix in the Experimental Acute Aortic Regurgitation Model in Rats

Mechanisms involved in cardiac remodelling by aortic regurgitation (AR) and the moment when cardiac dysfunction begins are largely unknown. This study aimed to investigate cardiac morphology and function after 1, 4, 8, and 12 weeks of experimental AR in Wistar rats. Extracellular matrix was also investigated as the potential mechanism that underlies the AR remodelling process. Male Wistar rats underwent surgical acute AR (AR group, n=51) or a sham surgery (sham group, n=32). After the procedure, serial transthoracic echocardiograms were performed at 1, 4, 8, and 12 weeks. Morphometry of cardiac tissue and the activities of metalloproteinase 2 (MMP-2) and tissue metalloproteinase inhibitor-1 (TIMP-1) were analysed. Statistical analysis was performed by two-way ANOVA. Significance level was 5%. The AR group presented an increase in the sphericity index (week 1); an increase in the left atrium, left ventricular mass index, TIMP-1 and MMP-2 activities, and collagen fraction (week 4); an increase in myocyte area (week 8); and a reduction in fraction shortening (week 12). First, the chamber became more spherical; second, MMP-2 and TIMP-1 were activated and this may have contributed to hypertrophy and atrial enlargement, until systolic dysfunction occurred. This study showed a sequence of abnormalities that preceded myocardial dysfunction in an experimental model of AR. First, haemodynamic volume overload led to a more spherical left ventricle chamber. Second, MMP-2 and TIMP-1 transitorily increased and may have contributed to atrial enlargement, eccentric hypertrophy, and systolic dysfunction.

Loss of left ventricular rotation is a significant determinant of functional mitral regurgitation

AimTo evaluate insufficient rotational movement of the left ventricle (LV) as a potential novel mechanism for functional regurgitation of the mitral valve (FMR). Methods and resultsWe compared reference subjects and patients with LV dysfunction (LVD, ejection fraction EF < 50%) with and without FMR (regurgitant volume RVol>10 ml). Subjects without structural mitral valve pathology undergoing cardiac MRI were evaluated. Delayed enhancement, global LV remodeling parameters, systolic twist and torsion were measured (using manual and novel automated cardiac MRI tissue-tracking). The study included 117 subjects with mean ± SD age 50.4 ± 17.8 years, of which 30.8% were female. Compared to subjects with LVD without FMR (n = 31), those with FMR (n = 37) had similar clinical characteristics, diagnoses, delayed enhancement, EF, and longitudinal strain. Subjects with FMR had significantly larger left ventricles (EDVi:136.6 ± 41.8 vs 97.5 ± 26.2 ml/m, p < 0.0001) with wider separation between papillary muscles (21.1 ± 7.6 vs 17.2 ± 5.7 mm, p = 0.023). Notably, they had lower apical (p < 0.0001) but not basal rotation and lower peak systolic twist (3.1 ± 2.4° vs 5.5 ± 2.5°, p < 0.0001) and torsion (0.56 ± 0.38°/cm vs 0.88 ± 0.52°/cm, p = 0.004). In a multivariate model for RVol including age, gender, twist, LV end-diastolic volume, sphericity index and separation between papillary muscles, only gender, volume and twist were significant. Twist was the most powerful correlate (beta −2.23, CI -3.26 to −1.23 p < 0.001). In patients with FMR, peak systolic twist negatively correlates with RVol (r = −0.73, p < 0.0001). ConclusionReduced rotational systolic LV motion is significantly and independently associated with RVol among patients with FMR, suggesting a novel pathophysiological mechanism and a potential therapeutic target.

Fetal Echocardiography in Predicting Postnatal Outcome in Borderline Left Ventricle.

Prenatal prediction of postnatal univentricular versus biventricular circulation in patients with borderline left ventricle (bLV) remains challenging. This study investigated prenatal fetal echocardiographic parameters and postnatal outcome of patients with a prenatally diagnosed bLV. We report a retrospective study of bLV patients at four prenatal centers with a follow-up of one year. BLV was defined as z-scores of the left ventricle (LV) between -2 and -4. Single-ventricle palliation (SVP), biventricular repair (BVR), and no surgical or catheter-based intervention served as the dependent outcome. Prenatal ultrasound parameters were used as independent variables. Cut-off values from receiver operating characteristic curves (ROC) were determined for significant discrimination between outcomes. A total of 54 patients were diagnosed with bLV from 2010 to 2018. All were live births. Out of the entire cohort, 8(15 %) received SVP, 34 (63 %) BVR, and 12 (22 %) no intervention. There was no significant difference with regard to genetic or extracardiac anomalies. There were significantly more patients with endocardial fibroelastosis (EFE) in the SVP group compared to the BVR group (80 % vs. 10 %), (p < 0.001). Apex-forming LV (100 % vs. 70 %) and lack of retrograde arch flow (20 % vs. 80 %) were associated with no intervention (p < 0.001). With respect to BVR vs. SVP, the LV sphericity index provided the highest specificity (91.7 %) using a cutoff value of ≤ 0.5. The majority of bLV patients maintained biventricular circulation. EFE, retrograde arch flow, and LV sphericity can be helpful parameters for counseling parents and further prospective studies can be developed.

On the Left Ventricular Remodeling of Patients with Stenotic Aortic Valve: A Statistical Shape Analysis.

The left ventricle (LV) constantly changes its shape and function as a response to pathological conditions, and this process is known as remodeling. In the presence of aortic stenosis (AS), the degenerative process is not limited to the aortic valve but also involves the remodeling of LV. Statistical shape analysis (SSA) offers a powerful tool for the visualization and quantification of the geometrical and functional patterns of any anatomic changes. In this paper, a SSA method was developed to determine shape descriptors of the LV under different degrees of AS and thus to shed light on the mechanistic link between shape and function. A total of patients underwent computed tomography (CT) for the evaluation of valvulopathy were segmented to obtain the LV surface and then were automatically aligned to a reference template by rigid registrations and transformations. Shape modes of the anatomical LV variation induced by the degree of AS were assessed by principal component analysis (PCA). The first shape mode represented nearly 50% of the total variance of LV shape in our patient population and was mainly associated to a spherical LV geometry. At Pearson’s analysis, the first shape mode was positively correlated to both the end-diastolic volume (, ) and end-systolic volume (, and ), suggesting LV impairment in patients with severe AS. A predictive model built with PCA-related shape modes achieved better performance in stratifying the occurrence of adverse events with respect to a baseline model using clinical demographic data as risk predictors. This study demonstrated the potential of SSA approaches to detect the association of complex 3D shape features with functional LV parameters.

Abstract 16631: Predictors of Left Ventricular Dysfunction in Patients After Anatomic Repair of Congenitally Corrected Transposition of the Great Arteries

Introduction: After anatomic repair (AR) of congenitally corrected transposition of the great arteries (ccTGA), the left ventricle (LV) is re-established as the systemic ventricle. As such, LV dysfunction is an important factor in long-term patient morbidity. While predictors exist for successful AR, little is known regarding measures of LV function before and after AR, and no known predictors exist of worsening global longitudinal strain (GLS). Methods: All patients with ccTGA who survived to discharge after AR at a single institution from 2000-2018 were included. Pre-operative and discharge echocardiograms were reviewed and GLS analysis was performed. LV sphericity index was measured to determine the degree of ventricular septal shift; a lower index denotes more septal bowing into the LV. Logistic regression was used to identify factors associated with worsened GLS after AR. Results: Of 91 survivors (65% male), 51 underwent Senning/arterial switch (ASO) and 40 had Senning/Rastelli. Mean LV ejection fraction (EF) decreased from 66% to 61% after AR (p = 0.0003) with 26% having LVEF less than or equal to 55% (increased from 4% pre-op, p = 0.0003). Mean LV GLS was normal pre-op (-20.0% ± SD 4.1%) but worsened following AR (-16.5% ± 4.6%; p &lt;.0001); abnormal LV GLS (&gt; -18%) increased to 62% (vs 32% pre-op, p &lt;.0001). More patients undergoing Senning/ASO (78%) had abnormal LV GLS at discharge compared to those with a Senning/Rastelli (22%) (odds ratio [OR] 9.3, p &lt;.0001). Abnormal pre-op GLS (OR 5.8, p = 0.002) and lower LV sphericity index (OR 1.05, p = 0.01) were also significantly associated with worsening GLS at discharge. In multivariable analysis, all three remained independently associated with worsened LV GLS. Age at AR, ventricular looping, LV posterior wall thickness, and reintervention prior to discharge were not associated with changed LV GLS at discharge. Conclusions: Following AR of ccTGA, LVEF decreases but remains in the normal range, while LV GLS detects abnormalities. Risk factors for worsening GLS include abnormal pre-op LV GLS, lower LV sphericity index, and a Senning/ASO repair. Lower LV sphericity index, or more septal shift into the LV, may represent a “less trained” LV, highlighting the need for careful patient selection for AR.

Left Ventricular Sphericity Index is a reproducible bedside echocardiographic measure of geometric change between acute phase Takotsubo's syndrome and acute anterior myocardial infarction.

•TS and AMI are separate cardiac conditions with similar clinical presentations.•TS have a higher LVSI than AMI, indicating a more spherical left ventricle.•LVSI may be utilised acutely to assist differentiation of acute phase TS and AMI.

Sex differences in the evolution of left ventricle remodeling in rats with severe volume overload

BackgroundAortic valve regurgitation (AR) results in left ventricle (LV) volume overload (VO) leading to its dilation and hypertrophy (H). We study a rat model of severe AR induced by puncturing one or two leaflets using a catheter. Most of our studies were conducted in male animals. Recently, we started investigating if sex dimorphism existed in the AR rat model. We observed that AR females developed as much LVH as males but morphological remodeling differences were present. A head-to-head comparison of LV morphological and functional changes had never been performed in AR males (M) and females (F) using the latest modalities in cardiac imaging by echocardiography.MethodsWe performed a longitudinal study to evaluate the development of LV hypertrophy caused by chronic AR in male and female rats over 6 months. Sham-operated (sham) animals were used as controls.ResultsLV diastolic volumes (EDV) increased more over 6 months in sham males than in females (38% vs. 23% for EDV, both p < 0.01). AR resulted in significant LV dilation for both sexes (54% vs. 51% increase in EDV) vs. baseline values. Since normal cardiac growth was less in females, dilation from AR was relatively more important for them (88% (M) vs. 157% (F) increase in EDV over sham). AR caused LV wall thickening in both males and females. It happened sooner for AR females and was more important than in males (25% (M) vs. 56% (F) increase in septum thickness at 2 months and 10% (M) vs. 30% (F) at 6 months). We then evaluated if AR was associated with changes in LV strain using speckle-tracking 2D echocardiography. Global longitudinal strain remained similar between AR and sham animals. Circumferential strain was negatively modulated by AR but only in females and early after VO induction (13% (M) vs. 26% (F)).ConclusionAR resulted in more LV dilation and quicker wall thickening in female AR rats compared to males. Global circumferential strain was negatively modulated in AR females but not in males. AR also seemed to lead to a more spherical LV shape in females whereas; it kept mostly an ellipsoid shape in males. This can influence validity of mass estimation of the dilated LV in females by echocardiography.

Quantitative Assessment of Left Ventricular Dysfunction in Fetal Ebstein's Anomaly and Tricuspid Valve Dysplasia

Fetal Ebstein's anomaly and tricuspid valve dysplasia (EA/TVD) are associated with high perinatal mortality relative to pulmonary atresia with intact ventricular septum (PAIVS), despite both requiring redistribution of the cardiac output (CO) to the left ventricle (LV). LV dysfunction is suspected to contribute to adverse outcomes in EA/TVD. We sought to examine global and segmental LV function in fetal EA/TVD with comparison to normal controls and PAIVS. We hypothesized that LV dysfunction in EA/TVD is associated with abnormal LV remodeling and interventricular mechanics. We retrospectively identified 63 cases of fetal EA/TVD (40 with retrograde ductal flow) and 22 cases of PAIVS encountered from 2004 to 2015 and compared findings to 77 controls of comparable gestational age. We measured the combined CO and global LV function using two-dimensional, Doppler-derived, deformational (six-segmental vector velocity imaging) and dyssynchrony indices (DIs; SD of time to peak), and a novel global DI. EA/TVD fetuses demonstrated abnormal LV global systolic function with reduced ejection fraction, fractional area change, and CO, while in PAIVS we observed a normal ejection fraction, fractional area change, and CO. PAIVS, but not EA/TVD, demonstrated increased LV sphericity, suggestive of remodeling, and associated enhanced radial function in the third trimester. In contrast, while EA/TVD fetuses had normal LV segmental longitudinal strain, there was abnormal radial segmental deformation and LV dyssynchrony with increased SD of time to peak and DI. Fetal EA/TVD is associated with a lack of spherical remodeling and presence of mechanical dyssynchrony, which likely contribute to reduced CO and ejection fraction. Clinical monitoring of LV function is warranted in fetal EA/TVD. Further studies incorporating quantification of LV function into prediction models for adverse outcomes are required.

Dilated hypertrophy: a distinct pattern of cardiac remodeling in preterm infants.

Young adults born preterm have remodeled hearts, i.e., altered cardiac shape and size with impaired cardiac function. At present, the natural history and pattern of prematurity related cardiac remodeling are not clearly established. The aim of this study was to compare the left ventricle (LV) geometry and function of preterm infants at 36 weeks postmenstrual age (PMA) with gestation matched newborn infants. LV end diastolic volume index (LV EDVI), LV mass index (LVMI), relative wall thickness (RWT), and sphericity index (SI) were prospectively obtained with echocardiography. LV geometry was classified according to the Gaasch method. LV function was assessed by determining ejection fraction (EF), longitudinal strain (LS), mitral annulus systolic motion (s'), and estimated LV filling pressure (E/e'). Eighty-three preterm infants between 23 and 29 weeks gestation, and 40 infants of 36 weeks gestation at birth were analysed. LV EDVI, LVMI, SI, LS, s', and E/e' were higher in preterm group while RWT and EF were comparable between groups. LV showed normal geometry in 55.4%, physiological enlargement in 23% and dilated hypertrophy in 21.6% preterm infants. At 36 week, preterm infants have significantly dilated, hypertrophied, and more spherical LV with impaired diastolic function compared with PMA matched newborn infants.

Papillary muscles contribute significantly more to left ventricular work in dilated hearts.

Left ventricular (LV) dilatation results in increased sphericity and affects position and orientation of papillary muscles (PMs), which may influence their performed work. The aim of this study was to assess the contribution of PM to LV function and its changes with dilatation. Fifteen sheep were investigated. Ten animals were subjected to 8 weeks of rapid (180 bpm) pacing, inducing LV dilatation. Five animals served as controls. High-resolution gated computed tomography was performed to assess LV volumes, left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), sphericity index, and PM angle, width and fractional shortening. 18F-fluorodeoxyglucose positron emission tomography (PET) was used to measure glucose metabolism as surrogate of regional myocardial work. Spatial resolution of PET images was maximized by electrocardiogram- and respiratory-gating. 18F-fluorodeoxyglucose uptake was measured in PM and compared with remaining left ventricular myocardium (MYO) to obtain a PM/MYO ratio. Animals with dilated heart had a more spherical left ventricle, with reduced LVEF (P < 0.0001) and GLS (P < 0.0001). In dilated hearts, PET analysis revealed a higher contribution of both PM to LV myocardial work (P < 0.0001); and PM angle towards LV wall correlated with PM work, together with PM width and the LV sphericity index. Sphericity index and posterior PM angle were strongest determinants of posterior PM/MYO ratio (R2 = 0.754; P < 0.0001), while anterior PM/MYO was mostly determined by sphericity index and the PM width (R2 = 0.805; P < 0.0001). In dilated hearts, PM contribute relatively more to LV myocardial work. We hypothesize that this is caused by the more cross-sectional orientation of the subvalvular apparatus, which leads to a higher stress on the PM compared with the spherical LV walls. The reduced cross-sectional area of the PM may further explain their increased stress.

3D Morphological Changes in LV and RV During LVAD Ramp Studies

ObjectivesThe purpose of this study was to investigate the differential impact of the 2 most commonly available left ventricular assist device (LVAD) types on the right ventricle (RV) and left ventricle (LV) using 3-dimensional (3D) echocardiography-based analysis of ventricular morphology. BackgroundLVADs have emerged as common therapy for advanced heart failure. Recent data suggest that the heart responds differently to speed settings in the 2 main devices available (HeartMate II [HMII], St Jude Medical, Pleasanton, California, and HVAD, HeartWare International, Framingham, Massachusetts). The authors hypothesized that 3D echocardiographic assessment of LV and RV volumes and shape would help describe the differential impact of the 2 LVAD types on the heart. MethodsSimultaneous 3D echocardiography, ramp test, and right heart catheterization were performed in 31 patients with LVADs (19 with HMII and 12 with HVAD). Device speed was increased stepwise (8,000 to 12,000 for HMII and 2,300 to 3,200 revolutions per minute for HVAD). 3D echocardiographic full-volume LV and RV datasets were acquired, and endocardial surfaces were analyzed using custom software to calculate LV sphericity, conicity (perfect sphere/cone = 1) and RV septal and free-wall curvature (0 = flat; <0 = concave; >0 = convex). ResultsFor both devices, cardiac output increased and wedge pressure decreased with increasing speed. In HMII, LV volumes progressively decreased (meanΔ = 127 ml) as the LV became less spherical and more conical, whereas the RV volume initially remained stable, but subsequently increased at higher speeds (meanΔ = 60 ml). Findings for the HVAD were similar, but less pronounced (LV:meanΔ = 51 ml, RV:meanΔ = 22 ml), and the LV remained significantly more spherical even at high speeds. On average, in HMII patients, the RV septum became more convex (bulging into the LV) at the highest speeds whereas in HVAD patients, there was no discernable change in the RV septum. ConclusionsThe heart responds differently to pump speed changes with the 2 types of LVAD, as reflected by the volume and shape changes of both the LV and RV. Our study suggests that adding RV assessment to the clinical echo-ramp study may better optimize LVAD speed. Further study is needed to determine whether this would have an impact on patient outcomes.

Functional geometry of the left ventricle in dilated cardiomyopathy before and after resynchronization therapy

Aim. To analyse quantitative parameters of functional geometry of the left ventricle (LV) in patients with dilated cardiomyopathy (DCMP), to assess the changes in cardiac resynchronization therapy (CRT) and to reveal the relation of functional geometry of LV and its contractility. Material and methods. In DCMP patients group, who were directed to CRT according to the Guidelines of Russian Arhythmologists Society 2013, echocardiographic study was performed before and after CRT (at 5th day). Based on two-dimensional LV pictures the parameters were assessed in the cycle, as segmented kinetics of wall contraction, LV shape dynamics: sphericity index, Hibson, conicity of apical zone, Fourier shape complexity. Results. In DCMP patients the decrease of global ejection fraction <35% was followed with a decrease of systolic change of all sectoral squares of LV and enhancement of dimensional heterogeneity and asynchronicity of regional wall motion during cardiac cycle comparing to controls. There was negative correlation revealed between the proposed index of non-homogeneity and global ejection fraction. All shape indexes point to more spherical shape of LV in DCMP. However, opposite to controls, DCMP patients lack dynamical changes of shape indexes during cardiac cycle, that witnesses on significant disorders of wall motion coordination in cycle. After CRT there is significant re-coordination of LV wall motion, followed by restoration of non-homogeneity pattern of segmental kinetics, decrease of nonhomogeneity indexes and of asynchronicity and appearance of the dynamics of shape indexes changes during cardiac cycle. It was shown that end-systolic indexes of sphericity shape complexity of Fourier make it to separate patients who respond or does not on therapy, by clinical parameters. Changes of sphericity index between end diastole and end systole <3,5% selects patients with the highest prognostic significance comparing with other parameters. Conclusion. Disorders of functional geometry of the LV, particularly an increase of non-homogeneity and asynchronicity parameters of the regional motion of the wall, decrease of dynamical changes of LV sphericity indexes, might influence contractility and pumping function of the heart, and have diagnostic significance in selection of patients responding to CRT.

Posterior leaflet segment 2 plication in ischemic mitral regurgitation repair.

To evaluate the medium-term results of plication of posterior leaflet segment 2 in addition to ring annuloplasty in patients with functional ischemic mitral regurgitation. The study included 136 patients who underwent mitral valve repair with plication of posterior leaflet segment 2 for ischemic mitral regurgitation between 2004 and 2012. The direction and correlation of left ventricle sphericity and tethering area were established by Pearson correlation analysis in patients with or without recurrent mitral regurgitation in the medium term. Medium-term survival was 91.9% and freedom from moderate or severe mitral regurgitation was 89.6%. In medium-term follow-up, transthoracic echocardiography found a significant decrease in tethering area, coaptation height, and distance between the commissures compared to the pre-surgery values (p = 0.0001 in all). The distance between the papillary muscles was reduced compared to the pre-surgery period but it was not significant (p = 0.204). Pearson correlation analysis found no significant correlation between the tethering area and left ventricle sphericity in patients without recurrent mitral regurgitation (r = 0.15, p = 0.36), a highly positive correlation (r = 0.44, p < 0.001) in patients with mild recurrent mitral regurgitation, and a moderately positive correlation (r = 0.71, p < 0.01) in patients with moderate or severe recurrent mitral regurgitation. The tethering area, coaptation height, and distance between the commissures decreased significantly, thus posterior leaflet segment 2 plication in addition to ring annuloplasty may be the optional procedure to ensure freedom from moderate or severe mitral regurgitation.

Comparative assessment of the indices of the left ventricle post-infarction remodelling of the left ventricle and its dependence on the strategy of acute myocardial infarction management

Comparative assessment of the indices of post-infarction remodelling of the left ventricle was carried out in the patients with myocardium reperfusion (thrombolytic therapy) and without reperfusion. ECG was performed for all patients on admission to the hospital and then 3 and 6 months later. The results obtained demonstrated that after the acute period of myocardial infarction there was no difference between the parameters under control. At the same time the results of dynamic monitoring confirmed that later on the patients felt some peculiarities during the left ventricle remodelling process. Three months later there was an increase of the left ventricle sphericity index during the systoly in the patients of group II. Six months later the patients of group II showed significant difference in five indices of remodelling versus the patients on thrombolitic therapy.