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Background: Biventricular (BiV) pacing increases transmural repolarization heterogeneity due to epicardial to endocardial conduction from the left ventricular (LV) lead. However, limited evidence is available on concomitant changes in ventricular depolarization and repolarization and long-term outcomes of BiV pacing. Therefore, we investigated associations of BiV pacing-induced concomitant changes in ventricular depolarization and repolarization with mortality (i.e., LV assist device, heart transplantation, or all-cause mortality) and sustained ventricular arrhythmia endpoints., Methods: Consecutive BiV-defibrillator recipients with digital preimplantation and postimplantation electrocardiograms recorded between 2006 and 2015 at Duke University Medical Center were included. We calculated changes in QRS duration and corrected JT (JTc) interval and split them by median values. For simplicity, these variables were named QRS decreased (≤ -12 ms), QRS increased (> -12 ms), JTc decreased (≤22 ms), and JTc increased (> 22 ms) and subsequently used to construct four mutually exclusive groups., Results: We included 528 patients (median age, 68 years; male, 69%). No correlation between changes in QRS duration and JTc interval was observed (P = .295). Compared to QRS decreased /JTc increased , increased risk of the composite mortality endpoint was associated with QRS decreased /JTc decreased (hazard ratio [HR] = 1.62; 95% confidence interval [CI] = 1.09-2.43), QRS increased /JTc decreased (HR = 1.86; 95% CI = 1.27-2.71), and QRS increased /JTc increased (HR = 2.25; 95% CI = 1.52-3.35). No QRS/JTc group was associated with excess sustained ventricular arrhythmia risk (P = .400)., Conclusion: Among BiV-defibrillator recipients, QRS decreased /JTc increased was associated with the most favorable long-term survival free of LV assist device, heart transplantation, and sustained ventricular arrhythmias. Our findings suggest that improved electrical resynchronization may be achieved by assessing concomitant changes in ventricular depolarization and repolarization., (© 2020 Wiley Periodicals LLC.)

Echocardiography is a key tool in the management of patients with pulmonary arterial hypertension (PAH), but many potential parameters could be used to assess response to therapy. In this retrospective study of 48 patients with severe PAH at baseline, we examined echocardiographic variables before and after initiation of PAH-specific therapy to evaluate which measures of right ventricular (RV) function best correlated with clinical response to therapy as assessed by 6-minute walk distance (6MWD) and 3-year all-cause mortality. Tricuspid annular plane systolic excursion (TAPSE), mid-RV and basal-RV diameters, RV systolic pressure, and RV global longitudinal strain were all found to significantly improve after initiation of a PAH therapy. Decreases in right atrial area (r = -0.50, p = 0.002) and mid-RV diameter (r = -0.36, p = 0.03) were most strongly correlated with improvement in 6MWD. Pretreatment values of RA area (hazard ratio [HR] per 1 SD: 2.72; 95% confidence interval [CI] 1.58, 4.69), mid-RV diameter (HR 2.03; 1.20, 3.45), basal-RV diameter (HR 2.27; 1.40, 3.70), and RV global longitudinal strain (HR 2.36; 1.22, 4.56) were all associated with mortality risk. 6MWD and TAPSE were the 2 variables for which pretreatment measures (6MWD - HR 0.35; 0.17, 0.72; TAPSE - HR 0.41; 0.21, 0.82) and change with treatment (6MWD - HR 0.26; 0.10, 0.64; TAPSE - HR 0.40; 0.21, 0.77) were both significantly associated with 3-year mortality. Change in RV systolic pressure with treatment was significantly associated with mortality (HR 2.55; 1.23, 5.28,) but pretreatment baseline had no association (HR 1.48; 0.72, 3.06). Although many echocardiographic parameters change with initiation of PAH treatment, the strong association of both baseline TAPSE and change in TAPSE with mortality supports the ongoing use of TAPSE as an important measure in the assessment of disease severity and treatment response in PAH., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The association of a Classical left bundle branch block (LBBB) contraction pattern and better outcome after cardiac resynchronization therapy (CRT) has only been studied using vendor-specific software for echocardiographic speckle-tracked longitudinal strain analysis. The purpose of this study was to assess whether a Classical LBBB contraction pattern on longitudinal strain analysis using vendor-independent software is associated with clinical outcome in CRT recipients with LBBB., Methods: This was a retrospective cohort study including CRT recipients with LBBB, heart failure, and left ventricular (LV) ejection fraction ≤35%. Speckle-tracked echocardiographic longitudinal strain analysis was performed retrospectively on echocardiograms using vendor-independent software. The presence of a Classical LBBB contraction pattern was determined by consensus of two readers. The primary end point was a composite of time to death, heart transplantation or LV assist device implantation. Secondary outcome was ≥15% reduction in LV end-systolic volume. Intra- and inter-reader agreement of the longitudinal strain contraction pattern was assessed by calculating Cohen's κ., Results: Of 283 included patients, 113 (40%) were women, mean age was 66 ± 11 years, and 136 (48%) had ischemic heart disease. A Classical LBBB contraction pattern was present in 196 (69%). The unadjusted hazard ratio for reaching the primary end point was 1.93 (95% confidence interval, 1.36-2.76, p < 0.001) when comparing patients without to patients with a Classical LBBB contraction pattern. Adjusted for ischemic heart disease and QRS duration < 150 milliseconds the hazard ratio was 1.65 (95% confidence interval, 1.12-2.43, p = 0.01). Of the 123 (43%) patients with a follow-up echocardiogram, 64 of 85 (75%) of patients with a Classical LBBB contraction pattern compared to 13 of 38 (34%) without, had ≥15% reduction in LV end-systolic volume (p < 0.001). Cohen's κ were 0.86 (95% confidence interval, 0.71-1.00) and 0.42 (95% confidence interval, 0.30-0.54) for intra- and inter-reader agreement, respectively., Conclusion: Using vendor-independent strain software, a Classical LBBB contraction pattern is associated with better outcome in CRT recipients with LBBB, but inter-reader agreement for the classification of contraction pattern is only moderate.

Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500-1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis., (Copyright © 2018 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

The introduction of transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of patients with severe aortic stenosis (AS). However, despite the great clinical success of TAVI, less is known about the cardiac hemodynamics and structural changes to post-TAVI. We analyzed patients with AS who had a transthoracic echocardiography at most 6 months before index TAVI and follow-up transthoracic echocardiography 9 to 18 months later, performed at Duke University Medical Center from 2012 to 2014. A total of 152 TAVI patients with a median age of 81 years (median interquartile range 74 to 86) were included. TAVI resulted in the reduction of left ventricle (LV) mass index (g/m 2 ), median (interquartile range) 130 (115 to 157) pre versus 106 (85 to 135) post, p <0.001; LV end-diastolic volume (ml) 127 (105 to 143) pre versus 120 (100 to 143) post, p = 0.013; and LV end-systolic volume (ml) 55 (38 to 77) pre versus 45 (40 to 65) post, p = 0.027. TAVI also significantly improved LV global longitudinal strain (%) -14.4 (-11.3, -15.5) pre versus -14.8 (-12.2, -16.6) post (p <0.001, respectively). Post-TAVI LV mass regression was predicted by baseline LV mass and LV global longitudinal strain whereas post-TAVI LV ejection fraction was predicted by baseline LV ejection fraction, LV mass, and post-TAVI paravalvular leak. In conclusion, TAVI results in significant cardiac hemodynamic, geometrical, and functional changes at approximately 1-year postprocedure for patients with AS. Better baseline myocardial structure and function leads to more reverse remodeling., (Copyright © 2018. Published by Elsevier Inc.)

Transmit beamforming has a strong impact on several factors that govern image quality, field-of-view, and frame-rate in ultrasound imaging. For cardiac applications, the visualization of fine structures and the ability to track their motion is equally important. Consequently, beamforming choices for echocardiography aim to optimize these trade-offs. Acoustic clutter can dramatically impact image quality and degrade the diagnostic value of cardiac ultrasound imaging. Clutter levels, however, are closely tied to the choice of beamforming configuration. This study aims to quantify the impact of transmit beamforming on clutter levels under in vivo conditions. The performance of focused as well as plane wave transmit configurations in fundamental and harmonic modes is evaluated under matched conditions. Contrast between the cardiac chambers and the interventricular septum is used as a surrogate for the level of clutter in a given imaging scenario. Under in vivo conditions, contrast was found to improve incrementally across the four beamforming configurations in the following order: fundamental-plane, fundamental-focused, harmonic-plane, and harmonic-focused. Using the fundamental-focused configuration as a reference, the harmonic-plane and harmonic-focused cases showed improvements in median contrast of 2.97 dB and 6.1 dB, respectively, while the fundamental-plane case showed a contrast deterioration of 1.23 dB. Contrast was also found to vary systematically as a function of imaging depth. Median contrast for the right ventricle (shallow chamber) was measured to be 2.96 dB lower than that in the left ventricle (deep chamber).

Background: Right ventricular peak systolic longitudinal strain (RVLS) has emerged as an approach for quantifying right ventricular function in diseases such as pulmonary hypertension and congenital heart disease. A major limitation in applying RVLS is that strain imaging and analysis are proprietary, which may result in systematic differences from vendor to vendor. The goal of this study was to test the reproducibility of right ventricular strain analysis among selected vendor-specific software (VSS) and vendor-independent software (VIS) on images obtained from different ultrasound scanners, as would be common in clinical practice or in a multicenter clinical trial., Methods: In this prospective, single-center study, 35 patients (5 healthy subjects and 30 with pulmonary hypertension) each underwent two echocardiographic scans, one using GE (Vivid E9) and the other using Philips (iE33) ultrasound systems. Images were analyzed using both VSS and VIS (TomTec) software for determination of RVLS. A repeated-measures analysis of variance was used to assess for any systematic differences among methods, as well as effects of scanner and software and a possible interaction between scanner and software for each strain measurement., Results: Differences for global strains were not statistically significant among VSS packages (P ≥ .05), but some differences were noted between VSS and VIS. Wide variability between regional peak strain measurements was noted, but no systematic differences were found., Conclusions: Global RVLS values between VSS systems are not significantly different but may differ slightly from VIS. When comparing regional strain between VSS and VIS analyses, there is widespread variability without clear systematic differences., (Copyright © 2018 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

We compared the incidence of left ventricular systolic dysfunction (LVSD) among patients with left bundle branch block (LBBB) to a matched cohort of patients with a narrow QRS duration <120 ms (NQRS). We hypothesized patients with preserved ejection fraction (EF) ≥50% and LBBB would have higher incidence of LVSD compared with a matched population of NQRS patients. Patients with LBBB on electrocardiogram within 30 days of a baseline echocardiogram with EF ≥50%, who had at least 1 follow-up echocardiogram ≥6 months later, were matched 1:1 on risk factors for cardiomyopathy to patients with NQRS. Incident LVSD was defined as a decline in EF to ≤45% on follow-up echocardiogram, or heart transplant, receipt of a cardiac device for LVSD (defibrillator or biventricular pacemaker), or implantation of a left ventricular assist device ≥6 months post baseline echocardiogram. Relative risk was calculated using conditional Poisson regression techniques. The final study cohort consisted of 188 patients, 94 with LBBB and 94 with NQRS. On follow-up, progression to LVSD was noted in 36% of LBBB patients and 10% of NQRS patients. The relative risk for LVSD in patients with LBBB was 3.78 (95% confidence interval = 1.98 to 7.19). In conclusion, there is a strong association between LBBB and the subsequent development of LVSD independent of common risk factors for cardiomyopathy., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: In patients with suspected native valve infective endocarditis, current guidelines recommend initial transthoracic echocardiography (TTE) followed by transesophageal echocardiography (TEE) if clinical suspicion remains. The guidelines do not account for the quality of initial TTE or other findings that may alter the study's diagnostic characteristics. This may lead to unnecessary TEE when initial TTE was sufficient to rule out vegetation., Methods: The objective of this study was to determine if the use of a strict definition of negative results on TTE would improve the performance characteristics of TTE sufficiently to exclude vegetation. A retrospective analysis of patients at a single institution with suspected native valve endocarditis who underwent TTE followed by TEE within 7 days between January 1, 2007, and February 28, 2014, was performed. Negative results on TTE for vegetation were defined by either the standard approach (no evidence of vegetation seen on TTE) or by applying a set of strict negative criteria incorporating other findings on TTE. Using TEE as the gold standard for the presence of vegetation, the diagnostic performance of the two transthoracic approaches was compared., Results: In total, 790 pairs of TTE and TEE were identified. With the standard approach, 661 of the transthoracic studies had negative findings (no vegetation seen), compared with 104 studies with negative findings using the strict negative approach (meeting all strict negative criteria). The sensitivity and negative predictive value of TTE for detecting vegetation were substantially improved using the strict negative approach (sensitivity, 98% [95% CI, 95%-99%] vs 43% [95% CI, 36%-51%]; negative predictive value, 97% [95% CI, 92%-99%] vs 87% [95% CI, 84%-89%])., Conclusions: The ability of TTE to exclude vegetation in patients is excellent when strict criteria for negative results are applied. In patients at low to intermediate risk with strict negative results on TTE, follow-up TEE may be unnecessary., (Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background: Speckle-tracking strain is almost universally cited as being independent of angle of insonation, but there are minimal confirmatory studies, and this claim may not be consistent with the known limitations of ultrasound axial and lateral spatial resolution. The aim of this study was to assess the influence of angle and depth on longitudinal peak systolic strain (LPS)., Methods: Thirty-four healthy pediatric subjects (age range, 6-18 years; 47% male) with normal cardiac anatomy and good image quality were prospectively imaged. Angular comparisons of LPS were investigated by examining interangle reproducibility on the basis of one standard and one alternative image acquisition relative to intraobserver reproducibility of two standard views of the same left ventricular segments. A single-window comparison was used to evaluated septal LPS: standard apical four-chamber versus right ventricular centered four-chamber. Two paired standard and alternative window comparisons were as follows: (1) four-chamber: standard apical versus subcostal; and (2) three-chamber: standard apical versus parasternal long-axis., Results: The global LPS intraobserver difference using the paired standard and alternative window comparisons was lower than the interangle difference in global LPS (-1.0 ± 0.1% vs -2.1 ± 2.4%). Intraobserver reproducibility was significantly higher than interangle reproducibility (intraclass correlation coefficient = 0.9 vs 0.29, P < .001). Similar results were found in the segmental strain analysis. Interangle reproducibility was significantly decreased compared with intraobserver reproducibility in the septal single-window comparison. Target depth assessment demonstrated a systematic bias between the near-field and far-field segments., Conclusions: Echocardiographically derived LPS values were modestly dependent on angle of insonation and target depth in this pediatric population. Normal strain ranges derived from standard apical images should not be applied to strain derived from sub-costal images, off-axis apical imaging, or applications in which a standard window cannot be defined., (Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background: Right ventricular (RV) function is a strong predictor of mortality in pulmonary hypertension (PH), but two-dimensional (2D) echocardiography-derived assessments of RV function that could aid in risk assessment and management of patients with PH are of limited utility. RV longitudinal peak systolic strain (RVLS) derived from 2D speckle-tracking echocardiography is a relatively novel method for quantifying RV function but typically is derived from a single apical four-chamber view of the right ventricle and may have inherent limitations. The objective of this study was to determine the utility of regional and global RVLS calculated from multiple views of the right ventricle to comprehensively assess RV function in a cohort of patients with PH., Methods: Regional and global RVLS were obtained from multiple views of the right ventricle (centered on the right ventricle-focused apical position) in 40 patients with PH, defined as a mean pulmonary artery pressure ≥ 25 mm Hg, most of whom also had pulmonary capillary wedge pressures ≤ 15 mm Hg and were thus defined as having pulmonary arterial hypertension. This was compared with other 2D echocardiography-derived parameters of RV function and functional parameters., Results: Global RVLS calculated from multiple views had a superior correlation with 6-min walk distance compared with other parameters of RV function, including tricuspid annular plane systolic excursion, RV myocardial performance index, and fractional area change. Although global RVLS calculated from multiple views displayed a similar correlation with 6-min walk distance as global RVLS calculated from a single four-chamber view, analysis of regional strains provided by multiple views identified distinct patterns of RV dysfunction, consisting of global, free wall, or septal dysfunction, that were associated with specific clinical characteristics., Conclusions: Global RVLS derived from multiple right ventricle-focused views yields a comprehensive quantitative assessment of regional and global RV function that correlates moderately with functional parameters and may be useful in the assessment of PH. Distinct patterns of regional RV dysfunction are associated with different clinical characteristics., (Copyright © 2014 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Background: Although quantitative right ventricular (RV) strain analysis may be useful in congenital and acquired heart disease populations with RV failure, a comprehensive, standardized approach is lacking. An 18-segment RV strain analysis obtained from three standardized RV apical echocardiographic images was used to determine the feasibility, normal values, and reproducibility of the method in normal adults., Methods: Forty healthy, prospectively enrolled volunteers with no cardiac histories and normal QRS durations underwent echocardiography optimized for strain analysis including three RV apical views. Two-dimensional speckle-tracking longitudinal strain analysis was performed using EchoPAC software. Eleven retrospectively identified subjects with RV disease were included as a pilot population. All had been imaged using the same protocol including the three RV apical views., Results: All control subjects had normal anatomic morphology and function by echocardiography. Feasibility of the RV strain analysis was good (adequate tracking in 696 of 720 segments [97%]). RV global peak systolic strain was -23 ± 2%. Peak strain was highest in the RV free wall and lowest in the septum. Dyssynchrony indices demonstrated no dyssynchrony using left ventricular criteria. Reproducibility of most strain measures was acceptable. This methodology identified important disease not seen in the four-chamber apical view alone in the pilot population of 11 patients with RV disease. Strain patterns and values were different from those in the control population, indicating that differences do exist from normal., Conclusions: Eighteen-segment RV strain analysis is feasible, with strain measures falling into discrete ranges in this normal population. Those with RV disease illustrate the potential utility of this approach. These data indicate that this model can be used for more detailed studies evaluating abnormal RV populations, in which its full potential can be assessed., (Crown Copyright © 2014. Published by Mosby, Inc. All rights reserved.)

Short-lag spatial coherence (SLSC) imaging is a novel beamforming technique that reduces acoustic clutter in ultrasound images. A clinical study was conducted to investigate clutter reduction and endocardial border detection in cardiac SLSC images. Individual channel echo data were acquired from the left ventricle of 14 volunteers, after informed consent and institutional review board approval. Paired B-mode and SLSC images were created from these data. Contrast, contrast-to-noise, and signal-to-noise ratios were measured in paired images, and these metrics were improved with SLSC imaging in most cases. Three cardiology fellows rated the visibility of endocardial segments in randomly ordered B-mode and SLSC cine loops. SLSC imaging offered 22%-33% improvement (p < 0.05) in endocardial border visibility when B-mode image quality was poor (i.e., 80% or more of the endocardial segments could not be visualized by the three reviewers). The percentage of volunteers with poor-quality images was decreased from 21% to 7% with the SLSC beamformer. Results suggest that SLSC imaging has the potential to improve clinical cardiac assessments that are challenged by clutter., (2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved)

Unlabelled: Aim The presence of septal hypertrophy in hypertrophic cardiomyopathy (HCM) is common. To date, there has been no accepted classification of septal morphology in HCM. Furthermore, the possible relationship between septal morphology and clinical features of HCM is undefined., Methods and Results: Seventy-five consecutive adult patients with HCM were enrolled. Septal morphologies were retrospectively categorized into one of four patterns of hypertrophy based on transthoracic echocardiography. Left ventricular diastolic function by Doppler echocardiography and late gadolinium enhancement (LGE) by magnetic resonance imaging were assessed in all patients. Patients were followed for a mean of 45 ± 32 months. Catenoid septum was the most common morphologic subtype (46 of 75, 61%), followed by simple sigmoid (22 of 75, 29%), neutral (4 of 75, 5%), and apical (3 of 75, 4%). Inter-observer reproducibility of septal classifications was high (κ = 0.95). Patients with the catenoid subtype presented at a younger age, had worse diastolic function, and high rates of LGE. The presence of catenoid septal morphology was independently associated with LGE in multivariable logistic regression analysis. Implantable cardioverter-defibrillator implantation for prevention of sudden cardiac death occurred only in patients with this septal morphology., Conclusion: We propose a simple, reproducible classification system of patterns of septal hypertrophy in HCM. These patterns of hypertrophy are associated with significant differences in clinical, haemodynamic, and myocardial characteristics. Further studies are needed to evaluate the relationship between septal morphology and outcome or response to therapies in HCM.

Background: PR interval prolongation is associated with poor outcome after cardiac resynchronization therapy (CRT) among patients with left bundle branch block (LBBB) but the mechanisms are unknown. We investigated clinical outcomes, electrocardiogram (ECG), and echocardiogram changes after CRT by PR interval. Methods: This is a retrospective study of CRT recipients with a baseline ejection fraction ≤35% and ECG showing sinus rhythm and LBBB. Patients were stratified by baseline PR interval quartile and the primary combined endpoint was time to heart transplantation, left ventricular assist device (LVAD) implantation, or death. ECG, echocardiogram, and clinical variables were compared to identify mechanisms for observed differences in outcomes. Results: Of 291 eligible patients, the mean age was 65 years, 60% were male, and 19% had prior atrial fibrillation. Patients with PR prolongation (quartile 4, PR > 200 ms) more frequently had a history of atrial fibrillation, coronary artery bypass graft surgery, prior implantable cardioverter defibrillator implantation, and use of amiodarone than patients in PR quartiles 1‐3. A PR > 200ms was associated with an adjusted hazard ratio of 1.7 (95% CI: 1.1‐2.5) for the primary endpoint. Patients with PR > 200 ms had less reduction in QRS duration and QRS area after CRT while having more increase in QT and QTc intervals than patients with PR ≤ 200 ms. No major differences were observed in echocardiography by baseline PR interval quartiles. Conclusions: PR prolongation predicts shorter survival free of heart transplantation or LVAD implantation in patients with LBBB. This may be due to inadequate ventricular resynchronization. [ABSTRACT FROM AUTHOR]