Left Ventricular Measurements Research Articles

M-Mode Echocardiography in Canine Veterinary Practice: A Comprehensive Review of Left Ventricular Measurements in 44 Different Dog Breeds.

This review article focuses on the use of canine M-mode in veterinary medicine, specifically in assessing the left ventricle measurements in several breeds. It traces the historical development of echocardiography techniques, including A-mode, B-mode, and motion mode (M-mode), which provide accurate unidimensional records of cardiac structures. This article highlights the significance of M-mode measurements in diagnosing stage B2 of MMVD, where left ventricular end-diastolic internal diameter corrected with body weight (LVIDdN) is essential for identifying cardiac enlargement. It also explains the role of M-mode in diagnosing DCM, outlining criteria such as left ventricular dilatation. The authors emphasize the importance of breed-specific reference values for echocardiographic measurements due to variations in somatotype among dogs. This review provides a comprehensive table summarizing M-mode measurements of the left ventricle for 44 different dog breeds, including interventricular septum thickness, left ventricular internal diameter, and left ventricular posterior wall thickness during systole and diastole. This review's methodology involves compiling data from various scientific literature sources, providing an extensive tabular representation of M-mode measurements for different breeds, ages, and sexes. Overall, this review highlights the critical role of M-mode echocardiography in diagnosing and managing cardiac diseases in dogs, underscores the importance of breed-specific reference values, and presents a comprehensive summary of M-mode measurements for various dog breeds, aiding both clinicians and researchers.

Pregnancy-induced physiological hypertrophic preconditioning attenuates pathological myocardial hypertrophy by activation of FoxO3a.

Previous studies show a woman's pregnancy is correlated with post-reproductive longevity, and nulliparity is associated with higher risk of incident heart failure, suggesting pregnancy likely exerts a cardioprotection. We previously reported a cardioprotective phenomenon termed myocardial hypertrophic preconditioning, but it is unknown whether pregnancy-induced physiological hypertrophic preconditioning (PHP) can also protect the heart against subsequent pathological hypertrophic stress. We aimed to clarify the phenomenon of PHP and its mechanisms. The pluripara mice whose pregnancy-induced physiological hypertrophy regressed and the nulliparous mice underwent angiotensin II (Ang II) infusion or transverse aortic constriction (TAC). Echocardiography, invasive left ventricular hemodynamic measurement and histological analysis were used to evaluate cardiac remodeling and function. Silencing or overexpression of Foxo3 by adeno-associated virus was used to investigate the role of FoxO3a involved in the antihypertrophic effect. Compared with nulliparous mice, pathological cardiac hypertrophy induced by Ang II infusion, or TAC was significantly attenuated and heart failure induced by TAC was markedly improved in mice with PHP. Activation of FoxO3a was significantly enhanced in the hearts of postpartum mice. FoxO3a inhibited myocardial hypertrophy by suppressing signaling pathway of phosphorylated glycogen synthase kinase-3β (p-GSK3β)/β-catenin/Cyclin D1. Silencing or overexpression of Foxo3 attenuated or enhanced the anti-hypertrophic effect of PHP in mice with pathological stimulation. Our findings demonstrate that PHP confers resistance to subsequent hypertrophic stress and slows progression to heart failure through activation of FoxO3a/GSK3β pathway.

A task-unified network with transformer and spatial–temporal convolution for left ventricular quantification

Quantification of the cardiac function is vital for diagnosing and curing the cardiovascular diseases. Left ventricular function measurement is the most commonly used measure to evaluate the function of cardiac in clinical practice, how to improve the accuracy of left ventricular quantitative assessment results has always been the subject of research by medical researchers. Although considerable efforts have been put forward to measure the left ventricle (LV) automatically using deep learning methods, the accurate quantification is yet a challenge work as a result of the changeable anatomy structure of heart in the systolic diastolic cycle. Besides, most methods used direct regression method which lacks of visual based analysis. In this work, a deep learning segmentation and regression task-unified network with transformer and spatial–temporal convolution is proposed to segment and quantify the LV simultaneously. The segmentation module leverages a U-Net like 3D Transformer model to predict the contour of three anatomy structures, while the regression module learns spatial–temporal representations from the original images and the reconstruct feature map from segmentation path to estimate the finally desired quantification metrics. Furthermore, we employ a joint task loss function to train the two module networks. Our framework is evaluated on the MICCAI 2017 Left Ventricle Full Quantification Challenge dataset. The results of experiments demonstrate the effectiveness of our framework, which achieves competitive cardiac quantification metric results and at the same time produces visualized segmentation results that are conducive to later analysis.

Perinatal factors impacting echocardiographic left ventricular measurement in small for gestational age infants: a prospective cohort study

IntroductionInfants born small for gestational age (SGA) have an increased risk of developing various cardiovascular complications. While many influencing factors can be adjusted or adapt over time, congenital factors also have a significant role. This study, therefore, seeks to explore the effect of perinatal factors on the left ventricular (LV) parameters in SGA infants, as assessed immediately after birth.Methods and materialsThis single-center prospective cohort study, conducted between 2014 and 2018, involved healthy SGA newborns born > 35 weeks’ gestation, delivered at New York-Presbyterian Brooklyn Methodist Hospital, and a gestational age (GA)-matched control group of appropriate for gestational age (AGA) infants. Data analysis was performed using multivariate linear regression in STATA.ResultsThe study enrolled 528 neonates, 114 SGA and 414 AGA. SGA infants exhibited a mean GA of 38.05 weeks (vs. 38.54), higher male representation (69.3% vs. 51.5%), lower birth weight (BW) (2318g vs 3381g), lower Apgar scores at birth, and a higher rate of neonatal intensive care unit admission compared to AGA infants (41.2% vs.18.9%; p<0.001). Furthermore, SGA infants were more likely to be born to nulliparous women (63.16% vs. 38.16%; p<0.001), with lower body mass index (BMI) (29.8 vs. 31.7; p=0.004), a lower prevalence of gestational maternal diabetes (GDM) (14.9 % vs. 35.5%; p<0.001), and a higher prevalence of preeclampsia (18.4 % vs. 6.52%; p<0.001). BW was identified as the most significant predictor affecting most LV parameters in this study (p<0.001), except shortening fraction, asymmetric interventricular septal hypertrophy and Inter-ventricular septal thickness/LV posterior wall ratio (IVS/LVPW). Lower GA (coefficient = -0.09, p=0.002), insulin use in GDM (coefficient = 0.39, p=0.014), and low APGAR scores at 1 minute (coefficient = -0.07, p<0.001) were significant predictors of IVS during diastole (R-squared [R2]=0.24). High maternal BMI is marginally associated with LVPW during systole (R2=0.27, coefficient = 0.01, p=0.050), while male sex was a significant predictor of LV internal dimension during diastole (R2=0.29, p=0.033).ConclusionThis study highlights the significant influence of perinatal factors on LV parameters in SGA infants, with BW being the most influential factor. Although LV morphology alone may not predict future cardiovascular risk in the SGA population, further research is needed to develop effective strategies for long-term cardiovascular health management in this population.

Chemotherapy-related cardiac dysfunction: the usefulness of myocardial work indices.

The role of left ventricular global longitudinal strain (GLS) in the diagnosis of subclinical cardiac damage induced by anticancer drugs is now consolidated. Considering some strain disadvantages such as the dependence on the haemodynamic loading conditions, the aim of our study was to investigate the usefulness of non-invasive myocardial work indices (MWI) derived from pressure-strain analysis, in the early diagnosis of cardiotoxicity. We enrolled 61 consecutive patients with breast cancer undergoing adjuvant treatment with anthracycline-containing chemotherapy followed by taxane + trastuzumab. Patients underwent a cardiological evaluation with 2D echocardiography including measurement of the left ventricular ejection fraction (LVEF) and other conventional parameters of systolic and diastolic function, GLS and MWI at baseline (T0), 3 months (T1) and 6 months (T2) after starting chemotherapy. At T1 and T2, we did not find a significant reduction in LVEF but we found a significant reduction in GLS and MWI (p value < 0.05). In addition, at T2, 31% of patients developed subclinical cardiac dysfunction defined as a relative decrease ≥ 12% of GLS from baseline. Global work index (GWI), global constructive work (GCW) and global work efficiency (GWE) decreased significantly in both patients with subclinical dysfunction and in those without subclinical dysfunction (p value < 0.05). Patients with subclinical dysfunction at T2 showed lower values of GCW at T0. MWI changed significantly during chemotherapy and appeared to alter precociously compared to GLS. Therefore, a multiparametric approach including left ventricular GLS and MWI measurements should be used in the evaluation of patients undergoing cardiotoxic antineoplastic treatment.

Preoperative left ventricular diastolic dimension index is associated with outcomes after HeartMate 3 implantation.

We investigated the association between indexed left ventricular diastolic dimension and clinical outcomes after HeartMate 3 implantation. We retrospectively reviewed patients implanted with the HeartMate 3 at our centre between November 2014 and September 2021. Left ventricular diastolic dimension was assessed via preoperative transthoracic echocardiography and left ventricular diastolic dimension index was calculated as left ventricular diastolic dimension/body surface area. The primary outcome was a composite of death or readmission due to right heart failure or stroke. The cut-off left ventricular diastolic dimension index value most closely associated with outcomes was determined by receiver-operating characteristic curve and restricted cubic spline analyses. Left ventricular diastolic dimension index measurements were available for 252 of 253 (99.6%) patients. Using a left ventricular diastolic dimension index cut-off value of 33.5 mm/m2, the cohort was divided: left ventricular diastolic dimension index ≤ (n = 131) or > (n = 121) 33.5 mm/m2. While there were no significant differences in age, INTERMACS level and preoperative haemodynamics between groups, patients with smaller left ventricular diastolic dimension index were more likely to have a larger body surface area (2.1 vs 1.9 m2, P < 0.001), ischaemic cardiomyopathy [64 (49%) vs 40 (33%), P = 0.01] and smaller left atrium volume index [40.5 (32.3-54.0) ml/m2 vs 54.0 (43.0-66.8) ml/m2, P < 0.001]. Smaller left ventricular diastolic dimension index patients had significantly worse survival (74% vs 88%, log-rank P = 0.009) and freedom from adverse events (55% vs 73%, log-rank P = 0.005) at 3-year follow-up. Smaller left ventricular diastolic dimension index was independently associated with the composite outcome (Hazard ratio 2.24, P = 0.002). Smaller preoperative left ventricular diastolic dimension index is associated with worse outcomes in patients undergoing HeartMate 3 implantation.

Gender differences in two-dimensional and three-dimensional speckle tracking echocardiography left ventricular measurements among healthy preschool pediatric population

BackgroundSpeckle-tracking echocardiography (STE) is an upcoming echocardiographic modality to measure global as well as segmental left ventricular systolic function expressed numerically as strain values independent of angle and ventricular geometry. We conducted this prospective study on 200 healthy preschool children with structurally normal hearts, to determine gender-based differences in two-dimensional (2D) global longitudinal strain (GLS) and three-dimensional (3D) GLS.ResultsAge-matched 104 males and 96 females were included, 2D GLS results for the males showed longitudinal strain ranging from − 18.1 to − 29.8 with a mean of − 21.7202 ± 5.094322, while for females 2D GLS ranged from − 18.1 to − 30.7 with a mean of − 22.0646 ± 2.167802, also 3D GLS values were measured and compared based on gender, where 3D GLS in males ranged from − 18 to − 24 with a mean value of 20.49 ± 1.28, while for females ranged from − 17 to − 30 with a mean value of 20.47 ± 1.755. The gender-based difference for both 2D GLS and 3D GLS showed non-significant P values.ConclusionIn healthy subjects below 6 years, 2D STE and 3D STE values showed no difference between males and females, unlike the adult population, to the best of our knowledge, this is one of the few studies in the literature that aims at comparing these measurements in the healthy pediatric group. In routine clinical practice, these values may be used to assess myocardial function or the early signs of malfunction.

Enhanced detection of severe aortic stenosis via artificial intelligence: a clinical cohort study

ObjectiveWe developed an artificial intelligence decision support algorithm (AI-DSA) that uses routine echocardiographic measurements to identify severe aortic stenosis (AS) phenotypes associated with high mortality.Methods631 824 individuals with 1.08 million...

Left Ventricular Ejection Fraction Measurements Using Two-Dimensional Transthoracic Echocardiography Compared With Cardiac Magnetic Resonance Imaging in a Large Animal Infarct Model

Left Ventricular Ejection Fraction Measurements Using Two-Dimensional Transthoracic Echocardiography Compared With Cardiac Magnetic Resonance Imaging in a Large Animal Infarct Model

Consistency of left ventricular ejection fraction measurements in the early time course of STEMI.

Early after ST-segment elevation myocardial infarction (STEMI), initial LV reshaping and hypokinesia may affect analysis of LV function. Concomitant microvascular dysfunction may affect LV function as well. To perform a comparative evaluation of left ventricular ejection fraction (LVEF) and stroke volume (SV) by different imaging modalities to assess LV function early after STEMI. LVEF and SV were assessed using serial imaging within 24 h and 5 days after STEMI using cineventriculography (CVG), 2-dimensional echocardiography (2DE), 2D/3D cardiovascular magnetic resonance (CMR) (2D/3D) in 82 patients. 2D analyses of LVEF using CVG, 2DE and 2D CMR yielded uniform results within 24 h and 5 days of STEMI. SV assessment between CVG and 2DE was comparable, whereas values for SV were higher using 2D CMR (p < 0.01 all). This was due to higher LVEDV measurements. LVEF by 2D versus 3D CMR was comparable, 3D CMR yielded higher volumetric values. This was not influenced by infarct location or infarct size. 2D analysis of LVEF yielded robust results across all imaging techniques implying that CVG, 2DE, and 2D CMR can be used interchangeably early after STEMI. SV measurements differed substantially between imaging techniques due to higher intermodality-differences of absolute volumetric measurements.

The impact of real-time guiding by deep learning on test-retest variability of automated left ventricular systolic function measurements

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Norwegian University of Science and Technology, St. Olavs University Hospital, Central-Norway Health Authority. Background Left ventricular (LV) ejection fraction (EF) and left ventricular volumes are key parameters for characterisation of cardiac function. Test-retest variability of EF and LV end-diastolic volume (EDV) are dependent on image quality and analyses. Foreshortened LV recordings cause inaccuracies in estimation of EF and EDV. Real-time guiding of LV length using deep learning (DL) could improve standardization of image acquisition and reduce variability of automated analyses of EF (auto-EF) and EDV (auto-EDV). Purpose To study the impact of real-time feedback of LV length using a robust deep-learning (DL) software during echocardiography on variability of automated analyses of EF (auto-EF) and EDV (auto-EDV). Methods Patients with mixed cardiac pathology were consecutively included if they were in sinus rhythm without need for contrast. Three consecutive echocardiograms were performed; the first and second by two of three experienced sonographers (Sonographer 1 and 2) and the third (reference) by one of four cardiologists in random order, all affiliated to an EACVI accredited echocardiographic laboratory. All exams included the standard apical views, and the reference exams also included tri-plane recordings of the LV. All measurements were done retrospectively using automated algorithm for measuring. LV volumes were measured in four- and two-chamber views and averaged by the method of discs’ formula. LV EF was calculated as biplane measurements. The coefficients of variation (CV) between sonographers and cardiologists were compared for both LV EF and end-diastolic LV volume from biplane measurements. One-way ANOVA was used to estimate within-patient variation for automated and manual measurements. Results A total of 47 patients (47% women) were included with mean (SD) age 64 (15) years. There was no significant difference in CV for neither auto-EF nor auto-EDV using the DL tool (Table) compared to standard care. Manual and automated measurements of LV volumes and EF correlated well with R 0.91 and R 0.74, respectively (only data for EF shown in the figure). Conclusion Real-time guiding did not significantly reduce variation of automated analyses of LV volumes and EF when used by experienced sonographers. Further studies are needed to evaluate the effect of real-time guiding to optimize LV acquisition in inexperienced users.

Prognostic value of myocardial strain on cardiac magnetic resonance imaging in patients with non-ischemic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Myocardial strain measurements using feature tracking imaging (FTI) on cardiac magnetic resonance (CMR) has emerged as a reliable method for evaluating myocardial function. However, the prognostic value of left ventricular strain measurements on CMR remains unclear in patients with nonischemic cardiomyopathy (NICM). Purpose The purpose of this meta-analysis is to evaluate the association of myocardial strain measurements with adverse outcomes in patients with NICM. Methods A literature search was conducted for studies reporting on the association of left ventricular global longitudinal strain (LVGLS), left ventricular global circumferential strain (LVGCS), and left ventricular global radial strain (LVGRS) using FTI on CMR with cardiovascular outcomes on long term follow-up in patients with NICM. The primary endpoint was major adverse cardiac events (MACE). The search included the following databases: Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar. The search was not restricted to time or publication status. Results A total of 6 studies with 1004 participants (251 with MACE and 753 without MACE) met inclusion criteria. Mean follow-up duration was 39 months. Mean ejection fraction was 27%. Baseline LVGLS, LVGCS, and LVGRS were significantly lower in NICM patients who subsequently experienced MACE on follow-up compared to patients without MACE (SMD −0.58, 95% CI −1.01, −0.15; p&amp;lt;0.01; SMD −0.58, 95% CI −0.96, −0.21; p&amp;lt;0.01; SMD −0.43, 95% CI −0.81, −0.05; p = 0.03). Conclusions Myocardial strain measurement using FTI on CMR may represent a useful clinical tool for risk stratification of NICM patients at risk for adverse cardiac events.

Automated Detection of Apical Foreshortening in Echocardiography Using Statistical Shape Modelling

Automated detection of foreshortening, a common challenge in routine 2-D echocardiography, has the potential to improve quality of acquisitions and reduce the variability of left ventricular measurements. Acquiring and labelling the required training data is challenging due to the time-intensive and highly subjective nature of foreshortened apical views. We aimed to develop an automatic pipeline for the detection of foreshortening. To this end, we propose a method to generate synthetic apical-four-chamber (A4C) views with matching ground truth foreshortening labels. A statistical shape model of the four chambers of the heart was used to synthesise idealised A4C views with varying degrees of foreshortening. Contours of the left ventricular endocardium were segmented in the images, and a partial least squares (PLS) model was trained to learn the morphological traits of foreshortening. The predictive capability of the learned synthetic features was evaluated on an independent set of manually labelled and automatically curated real echocardiographic A4C images. Acceptable classification accuracy for identification of foreshortened views in the testing set was achieved using logistic regression based on 11 PLS shape modes, with a sensitivity, specificity and area under the receiver operating characteristic curve of 0.84, 0.82 and 0.84, respectively. Both synthetic and real cohorts showed interpretable traits of foreshortening within the first two PLS shape modes, reflected as a shortening in the long-axis length and apical rounding. A contour shape model trained only on synthesized A4C views allowed accurate prediction of foreshortening in real echocardiographic images.

Feasibility of CMR Imaging during Biventricular Pacing: Comparison with Invasive Measurement as a Pathway towards a Novel Optimization Strategy.

This prospective pilot study assessed the feasibility of cardiovascular magnetic resonance (CMR) imaging during biventricular (BIV) pacing in patients with a CMR conditional cardiac resynchronization therapy defibrillator (CRT-D) and compared the results with invasive volume measurements. Ten CRT-D patients underwent CMR imaging prior to device implantation (baseline) and six weeks after device implantation, including CRT-on and CRT-off modes. Left ventricular (LV) function, volumes, and strain measurements of LV dyssynchrony and dyscoordination were assessed. Invasive pressure-volume measurements were performed, matching the CRT settings used during CMR. Post-implantation imaging enabled reliable cine assessment, but showed artefacts on late gadolinium enhancement images. After six weeks of CRT, significant reverse remodeling was observed, with a 22.7 ± 11% reduction in LV end-systolic volume during intrinsic rhythm (CRT-off). During CRT-on, the LV ejection fraction significantly improved from 27.4 ± 5.9% to 32.2 ± 8.7% (p < 0.01), and the strain assessment showed the abolition of the left bundle branch block contraction pattern. Invasively measured and CMR-assessed LV hemodynamics during BIV pacing were significantly associated. Post-CRT implantation CMR assessing acute LV pump function is feasible and provides important insights into the effects of BIV pacing on cardiac function and contraction patterns. LV assessment during CMR may constitute a future CRT optimization strategy.

The impact of intravenous ferric carboxymaltose on reverse electrical remodeling following cardiac resynchronization therapy

Abstract Funding Acknowledgements Type of funding sources: None. Background The effect of intravenous ferric carboxymaltose (FCM) on reverse electrical remodeling (RER) in patients with heart failure with reduced ejection fraction (HFrEF) following cardiac resynchronization therapy (CRT) implantation is unknown. Purpose The current study aims to examine the effect of iron replacement with intravenous FCM on RER in CRT-implanted patients with HFrEF and iron deficiency. Methods The present study retrospectively analyzed 65 patients with successful CRT-D device implantation between March 2017 and January 2020 with iron deficiency (defined as ferritin &amp;lt;100 μg/L) at implantation. Follow-up data were obtained from the 6-month routine follow-up visits of patients following CRT implantation. Demographic characteristics, laboratory results, medical history, medication details, functional status, information on whether intravenous FCM therapy was administered during CRT device implantation, echocardiographic left ventricular (LV) measurements, baseline electrocardiogram (ECG) recorded before CRT device implantation, and follow-up ECG were collected for analysis for each study patient. From baseline to 6-month follow-up, the change in intrinsic QRS duration (without biventricular pacing) was calculated as a primary endpoint, and the change in LV ejection fraction (LVEF) was assessed as a secondary endpoint of the study. Results Thirty-five of 65 patients were in the FCM group, while the remaining 30 study participants were in the non-FCM. The two study groups were similar regarding baseline characteristics, except for ferritin levels, which were minimally significantly lower in the FCM group (10.7±5.0μg/L vs 13.5 ±3.9μg/L, p= 0.012). At the 6-month follow-up, both mean ferritin levels increased significantly in the FCM group compared to baseline (from 10.7±5.0 to 86.5±7.6μg/L, p &amp;lt; 0.0001), while these levels were not significantly increased in the non-FCM group (from 13.5±3.9 to 14.1±4.2μg/L, p = 0.962). There was a significant reduction in intrinsic QRS durations compared to baseline at 6-month follow-up after CRT implantation in both FCM and non-FCM group (from 148.4±5.3 to 138.0±5.1ms, p &amp;lt; 0.0001; from 149.8±5.0 to 146.8±4.6ms, p &amp;lt; 0.0001, respectively). The change in intrinsic QRS duration from baseline to 6-month follow-up was significantly greater in the FCM group than in the non-FCM group (-10.4±2.2ms vs -3±2.9ms, p &amp;lt; 0.0001). At the 6-month follow-up, the change in LVEF from baseline was significantly higher in the FCM group than in the non-FCM group (+3.6±1.6% vs -0.1±1.7%, p &amp;lt; 0.0001). The change in ferritin level was negatively correlated with the change in intrinsic QRS duration (r = -0.725, p &amp;lt; 0.0001), whereas there was a positive correlation between the change in ferritin level and the change in LVEF (r = 0.712, p &amp;lt; 0.0001). Conclusions Treatment with FCM was induced RER and improvement in LVEF in HFrEF patients with iron deficiency following CRT implantation.

Real-time guiding by deep learning during echocardiography to reduce left ventricular foreshortening and measurement variability.

Apical foreshortening leads to an underestimation of left ventricular (LV) volumes and an overestimation of LV ejection fraction and global longitudinal strain. Real-time guiding using deep learning (DL) during echocardiography to reduce foreshortening could improve standardization and reduce variability. We aimed to study the effect of real-time DL guiding during echocardiography on measures of LV foreshortening and inter-observer variability. Patients (n = 88) in sinus rhythm referred for echocardiography without indication for contrast were included. All participants underwent three echocardiograms. The first two examinations were performed by sonographers, and the third by cardiologists. In Period 1, the sonographers were instructed to provide high-quality echocardiograms. In Period 2, the DL guiding was used by the second sonographer. One blinded expert measured LV length in all recordings. Tri-plane recordings by cardiologists were used as reference. Apical foreshortening was calculated at the end-diastole. Both sonographer groups significantly foreshortened the LV in Period 1 (mean foreshortening: Sonographer 1: 4 mm; Sonographer 2: 3 mm, both P < 0.001 vs. reference) and reduced foreshortening in Period 2 (2 and 0 mm, respectively. Period 1 vs. Period 2, P < 0.05). Sonographers using DL guiding did not foreshorten more than cardiologists (P ≥ 0.409). Real-time guiding did not improve intra-class correlation (ICC) [LV end-diastolic volume ICC, (95% confidence interval): DL guiding 0.87 (0.77-0.93) vs. no guiding 0.92 (0.88-0.95)]. Real-time guiding reduced foreshortening among experienced operators and has the potential to improve image standardization. Even though the effect on inter-operator variability was minimal among experienced users, real-time guiding may improve test-retest variability among less experienced users. ClinicalTrials.gov, Identifier: NCT04580095.

PO-02-235 MOVING BEYOND QRS DURATION: QRS VOLTAGE-TIME-INTEGRAL (AREA) IS A SUPERIOR PREDICTOR OF CLINICAL RESPONSE TO CARDIAC RESYNCHRONIZATION THERAPY

Cardiac resynchronization therapy (CRT) can alleviate left ventricular (LV) electrical dyssynchrony mediated systolic heart failure (HF). 15% reduction in LV end systolic volume (LVESV) with CRT is a validated surrogate of improved clinical outcomes. Prolonged baseline QRS duration (QRSd) is the only conventional quantitative ECG criteria to assess left ventricular electrical dyssynchrony. In addition to QRS duration, we evaluated the baseline QRS voltage-time-integral (VTI) and its reduction after CRT as predictors of LV reverse remodeling. We included 595 patients (68.1±11.5 yr., 32.6% women, 43.9% ischemic cardiomyopathy) who underwent CRT-defibrillator implant for clinical indications 2012-2019 and analyzed their ECGs before and after CRT. Orthogonal X, Y, Z leads were reconstructed from 12-lead ECG using Kors’s matrix. VTIQRS-X, Y ,Z and VTIQRS-3D were obtained from integration over the duration of QRS in X, Y, Z, and root-mean-squared (3D) ECGs respectively. We reviewed echocardiogram reports to obtain LV measures before and 3-12 months after CRT, including ejection fraction (LVEF), internal dimensions in diastole (LVIDd) and systole (LVIDs), end-diastolic (LVEDV) and LVESV. We used linear regression models to evaluate ECG variables as predictors of change in LV measures. We further used unadjusted and multivariable-adjusted logistic regression models to predict ≥15% reduction in LVESV from ECG variables. Baseline LVEF was 25.8±8.3%, LVIDd 5.7±0.9 cm, LVIDs 4.8±0.9 cm, LVEDV 164±67 and LVESV 109±56 mL. QRSd reduced from 153±26 to 137±22 ms with CRT. VTIQRS-3D and VTIQRS-Z of 104±49 and 75±44 respectively improved to 67±34 and 33±24 μVs. Baseline and change in VTIQRS-Z and VTIQRS-3D were more significantly associated with change in echo variables as compared to baseline and change in QRSd (Table 1). ≥15% reduction in LVESV was independently predicted by baseline VTIQRS-Z ≥71 μVs (OR 2.0, 95% CI 1.3-3.0, p=0.0009) and Δ VTIQRS-Z ≥42 μVs (OR 2.1, 1.4-3.1, p=0.004). In patients undergoing CRT, baseline QRS VTI from Z (anteroposterior) axis ECG ≥71 μVs independently predicted 2 times higher odds of salutary reverse LV remodeling post CRT. Further, a reduction in VTIQRS-Z ≥42 μVs also predicted more than 2 times odds of revrse remodeling. VTIQRS-Z is a superior automatically calculable quantitative summary ECG marker for CRT patient selection and prognostication as compared to QRS duration.

PO-03-044 EFFECT OF V1 PACED MORPHOLOGY DURING IMPLANTATION OF LEFT BUNDLE BRANCH AREA PACEMAKERS ON ECHOCARDIOGRAPHIC OUTCOMES

Left bundle branch area pacing (LBBAP) is an established form of physiologic pacing. Our group has reported on positive structural remodeling associated with LBBAP, but it is unknown whether implantation characteristics of LBBAP are predictive of subsequent ventricular function. To evaluate the effects of implant morphology and LBBAP on heart function as measured by standard 2D-echocardiography. Consecutive patients undergoing LBBAP implantation between Jan 2019 and July 2022 at Virginia Commonwealth University were analyzed. Ejection fraction (EF%), left ventricular end-diastolic dimension (LVIDd), and end-systolic dimension (LVIDs) as a function of paced morphology in V1 (qR, RSR, QS) were recorded. Patients with moderate to severe valvular regurgitation were evaluated irrespective of paced morphology. Regurgitation severity was coded on a three point scale, with moderate as ‘2’ and severe as ‘3’. A total of 247 patients with LBBAP had echocardiographic data and implant morphology available, with mean ventricular pacing burden of 67%. Mean follow up duration was 613 days ± 478 days. 29 patients had QS morphology at implant, with mean pre-implant EF of 56.8% ± 9.7% vs 57.0% ± 8.1% after implantation (p=0.821). In the 145 patients with qR morphology the mean pre and post-EF was 54.8% ± 10.8% vs 55.5% ± 7.9% (p=0.400). In the 73 patients with rSR morphology the pre-implant EF was 55.2% ± 10.9% vs 54.5% ± 10% (p=0.257). Left ventricular cavity measurements can be found in Table 1. In patients with moderate to severe tricuspid regurgitation (n=25) the mean severity was 2.16 ± 0.37 prior to LBBAP, and decreased to 1.28 ± 0.93 post-implant (p<0.001). Patients with moderate to severe MR (n=37) likewise decreased regurgitant severity from 2.16 ± 0.37 to 1.46 ± 0.83 (p<0.001). V1 paced morphology at time of implant was not associated with significant change in post-procedural systolic function or left ventricular dimensions. Conduction system pacing via LBBAP was associated with improved valvular regurgitation.

An integrated signature of extracellular matrix proteins and a diastolic function imaging parameter predicts post-MI long-term outcomes.

Patients suffering from acute myocardial infarction (AMI) are at risk of secondary outcomes including major adverse cardiovascular events (MACE) and heart failure (HF). Comprehensive molecular phenotyping and cardiac imaging during the post-discharge time window may provide cues for risk stratification for the outcomes. In a prospective AMI cohort in New Zealand (N = 464), we measured plasma proteins and lipids 30 days after hospital discharge and inferred a unified partial correlation network with echocardiographic variables and established clinical biomarkers (creatinine, c-reactive protein, cardiac troponin I and natriuretic peptides). Using a network-based data integration approach (iOmicsPASS+), we identified predictive signatures of long-term secondary outcomes based on plasma protein, lipid, imaging markers and clinical biomarkers and assessed the prognostic potential in an independent cohort from Singapore (N = 190). The post-discharge levels of plasma proteins and lipids showed strong correlations within each molecular type, reflecting concerted homeostatic regulation after primary MI events. However, the two molecular types were largely independent with distinct correlation structures with established prognostic imaging parameters and clinical biomarkers. To deal with massively correlated predictive features, we used iOmicsPASS + to identify subnetwork signatures of 211 and 189 data features (nodes) predictive of MACE and HF events, respectively (160 overlapping). The predictive features were primarily imaging parameters, including left ventricular and atrial parameters, tissue Doppler parameters, and proteins involved in extracellular matrix (ECM) organization, cell differentiation, chemotaxis, and inflammation. The network signatures contained plasma protein pairs with area-under-the-curve (AUC) values up to 0.74 for HF prediction in the validation cohort, but the pair of NT-proBNP and fibulin-3 (EFEMP1) was the best predictor (AUC = 0.80). This suggests that there were a handful of plasma proteins with mechanistic and functional roles in predisposing patients to the secondary outcomes, although they may be weaker prognostic markers than natriuretic peptides individually. Among those, the diastolic function parameter (E/e' - an indicator of left ventricular filling pressure) and two ECM proteins, EFEMP1 and follistatin-like 3 (FSTL3) showed comparable performance to NT-proBNP and outperformed left ventricular measures as benchmark prognostic factors for post-MI HF. Post-discharge levels of E/e', EFEMP1 and FSTL3 are promising complementary markers of secondary adverse outcomes in AMI patients.

Most Common Risk Factors Associated with Peripartum Cardiomyopathy amongst Kurdish Population

Background: Peripartum cardiomyopathy (PPCM) is idiopathic cardiomyopathy that presents during the last trimester or the first several months after delivery and it is a serious complication of pregnancy. Objectives: The aim was to assess the most common risk factors seen among pregnant women leading to PPCM and factors that are associated with better outcomes after therapy. Materials and Methods: A total of 20 patients who presented to the outpatient cardiology clinic and fulfilled the diagnostic criteria of the European Society of Cardiology were recruited to participate in the study. A detailed history was obtained and left ventricular measurements were evaluated using M-mode, 2-dimentional, and Simpson methods to estimate the ejection fraction. Data were analyzed using the Statistical Package for the Social Sciences. Results: Mean age at diagnosis was 34.7 ± 5.2 years. Multiparous women constituted 60% of the study sample. Gestational age at presentation ranged between 28 and 38 weeks, with a mean of 32.9 ± 2.6. Being overweight was a common feature as 60% of patients had above-normal body mass index. Family history was reported in 50% of patients, followed by passive smoking (35%), hypertension (25%), thyroid disorders (30%), and type II diabetes mellitus (20%). The mean left ventricular ejection fraction at the time of diagnosis was 32.3% ± 6.7% with an increase to 44.2% ± 8.9% at follow-up. Younger patients were more likely to regain normal left ventricular function following diagnosis (P = 0.005). Conclusion: These preliminary results strongly demonstrate that advanced maternal age, anemia, multiparity, and family history were the most common risk factors seen among our population.