Postnatal neonatal myocardial adaptation is associated with loss of tolerance to tachycardia: a simultaneous invasive and noninvasive assessment

Doppler studies at rest suggest left ventricular (LV) diastolic function rapidly improves from the neonate to infant. Whether this translates to its response to hemodynamic challenges is uncertain. We sought to explore the impact of early LV maturation on its ability to tolerate atrial tachycardia. As tachycardia reduces filling time, we hypothesized that the neonatal LV would be less tolerant of atrial tachycardia. Landrace cross piglets of two age groups (1–3 days; NPs; 14–17 days, YPs; n = 7/group) were instrumented for an atrial pacing protocol (from 200 to 300 beats/min) and assessed by invasive monitoring and echocardiography. NPs maintained their LV output and blood pressure, whereas YPs did not. Although negative dP/d t in NPs at baseline was lower than that of YPs (−1,599 ± 83 vs. −2,470 ± 226 mmHg/s, respectively, P = 0.007), with increasing tachycardia negative dP/d t converged between groups and was not different. Both groups had similar preload reduction during tachycardia; however, NPs maintained shortening fraction while YPs decreased (NPs: 35.4 ± 1.4 vs. 31.8 ± 2.2%, P = 0.35; YPs: 31.4 ± 0.8 vs. 22.9 ± 0.8%, P < 0.001). Contractility measures did not differ between groups. Peak LV twist and untwisting rate also did not differ; however, NPs tended to augment LV twist through increased apical rotation and YPs through increasing basal rotation ( P = 0.009). The NPs appear more tolerant of atrial tachycardia than the YPs. They have at least similar diastolic performance, enhanced systolic performance, and different LV twist mechanics, which may contribute to improved tachycardia tolerance of NPs.

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Abstract 17892: Strain Rate is Affected by Heart Rate in Younger Heart: A Simultaneous Invasive and Noninvasive in vivo Piglet Model

Circulation ◽

10.1161/circ.132.suppl_3.17892 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Etienne Fortin-Pellerin ◽

Lisa K Hornberger ◽

James Y Coe ◽

Lindsay Mills ◽

Jesus Serrano-Lomelin ◽

...

Keyword(s):

Heart Rate ◽

Strain Rate ◽

Atrial Tachycardia ◽

Young Infant ◽

Left Ventricular ◽

Baseline Heart Rate ◽

Force Frequency ◽

Filling Time ◽

Frequency Relationship ◽

The Impact

Introduction: In adult human and pig hearts, left ventricular (LV) systolic strain rate (SR) has been shown to be independent of heart rate (HR) in atrial tachycardia. It has been hypothesized that any increase in contractility related to the force-frequency relationship is balanced by a decrease in contractility due to reduced filling time and preload at higher HRs. In this study, we explore the impact of atrial tachycardia on SR of the young infant heart using a simultaneous invasive and noninvasive piglet model to determine whether SR of the immature heart is similarly not influenced by increasing HR. Methods: Under general anesthesia (propofol, isoflurane), 1 - 15 day old piglets were instrumented intravascularly with Millar high-fidelity and pacing catheters in the left ventricle and right atrium, respectively. After stabilization, invasive hemodynamic and echocardiography parameters were acquired at baseline, and at 200, 230 and 260bpm. Basal circumferential SR was analyzed off-line by speckle tracking (frame rates 247±7 Hz). Each animal was its own control and repeated measure ANOVA was used for comparison, data is expressed as mean ± SE. Results: Fourteen piglets of mean age 8.5±1.8 days, weight 3.6±0.5kg and baseline heart rate of 152±5bpm were assessed. Baseline LV systolic SR was -1.53±0.13 1/s and dP/dt 1656±115mmHg/s. With pacing, LV SR increased significantly (p = 0.002). The increase in SR mirrored the increase in contractility assessed invasively by dP/dt (p<0.001). M-mode LV end diastolic dimension decreased from baseline to 260bpm (73±9.9% of baseline value, p < 0.001) consistent with reduced preload with tachycardia. Conclusion: Our study suggests that in the younger heart, SR is augmented by atrial tachycardia itself even in the presence of decreased preload. This is in keeping with preservation of the force frequency relationship. Given our findings, HR should be taken into account when assessing contractility using SR in young patients.

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Abstract 4197: Does Relative Wall Thickness or Left Ventricular Mass Index Best Predict Mortality Risk in Patients With Preserved Systolic Function?

Circulation ◽

10.1161/circ.118.suppl_18.s_841 ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Dharmendrakumar A Patel ◽

Carl J Lavie ◽

Sangeeta Shah ◽

Yvonne Gilliland ◽

Richard V Milani

Keyword(s):

Wall Thickness ◽

Systolic Function ◽

Age Groups ◽

Left Ventricular ◽

Relative Wall Thickness ◽

Prognostic Impact ◽

Geometric Patterns ◽

Lv Mass ◽

Mortality Table ◽

The Impact

Background: Several studies have indicated that left ventricular (LV) geometric patterns predict cardiovascular events. However, little data is available that compares the relative prognostic impact of LV mass index (LVMI) and relative wall thickness (RWT) on mortality in a large cohort of patients with preserved systolic function. Methods: The impact of LVMI and RWT on mortality during an average follow-up of 1.7±1.0 years was examined in a sample of 47,701 patients (mean age: 61.6 ± 15.4; females=54.6 %) with preserved ejection fraction(EF), as well as in age groups of <50 yrs(n=10,864; mean age=39.9 ± 8.1; females=58.4 %), 50 –70 yrs (n=20,181; mean age=59.9 ± 5.7; females=52.2 %) and >= 70 yrs (n=16,836; mean age=77.7 ± 5.5; females=55.1 %). Results: With increasing age (<50, 50 –70, >=70 yrs), both LVMI (78.5 ± 23.4, 84.3 ± 25.4, 90.3 ± 27.6; p<0.0001) and RWT (0.37 ± 0.08, 0.41 ± 0.08, 0.43 ± 0.09; p<0.0001) as well as mortality (2.2%, 5.0%, 14.2%; p<0.0001) showed significant linear trends and were independent predictors of mortality (Table , Figure ). Conclusion: Although, both LVMI and RWT were independently associated with increased mortality in all groups, RWT was by far the strongest independent predictor of all-cause mortality, especially in younger patients.

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Maturational patterns of left ventricular rotational mechanics in pre-term infants through 1 year of age

Cardiology in the Young ◽

10.1017/s1047951120001912 ◽

2020 ◽

Vol 30 (9) ◽

pp. 1238-1246

Author(s):

Gloria C. Lehmann ◽

Philip T. Levy ◽

Meghna D. Patel ◽

Timothy Sekarski ◽

HongJie Gu ◽

...

Keyword(s):

Repeated Measures ◽

Neonatal Period ◽

Ductus Arteriosus ◽

Left Ventricular ◽

Term Infants ◽

Apical Rotation ◽

Cardiopulmonary Complications ◽

Rotational Mechanics ◽

The Impact ◽

Over Time

AbstractBackground:Pre-mature birth impacts left ventricular development, predisposing this population to long-term cardiovascular risk. The aims of this study were to investigate maturational changes in rotational properties from the neonatal period through 1 year of age and to discern the impact of cardiopulmonary complications of pre-maturity on these measures.Methods:Pre-term infants (<29 weeks at birth, n = 117) were prospectively enrolled and followed to 1-year corrected age. Left ventricular basal and apical rotation, twist, and torsion were measured by two-dimensional speckle-tracking echocardiography and analysed at 32 and 36 weeks post-menstrual age and 1-year corrected age. A mixed random effects model with repeated measures analysis was used to compare rotational mechanics over time. Torsion was compared in infants with and without complications of cardiopulmonary diseases of pre-maturity, specifically bronchopulmonary dysplasia, pulmonary hypertension, and patent ductus arteriosus.Results:Torsion decreased from 32 weeks post-menstrual age to 1-year corrected age in all pre-term infants (p < 0.001). The decline from 32 to 36 weeks post-menstrual age was more pronounced in infants with cardiopulmonary complications, but was similar to healthy pre-term infants from 36 weeks post-menstrual age to 1-year corrected age. The decline was due to directional and magnitude changes in apical rotation over time (p < 0.05).Conclusion:This study tracks maturational patterns of rotational mechanics in pre-term infants and reveals torsion declines from the neonatal period through 1 year. Cardiopulmonary diseases of pre-maturity may negatively impact rotational mechanics during the neonatal period, but the myocardium recovers by 1-year corrected age.

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P784 Cardiac remodelling in elite rowers - insights from novel echocardiographic techniques

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jez319.443 ◽

2020 ◽

Vol 21 (Supplement_1) ◽

Author(s):

G Kleinnibbelink ◽

N M Panhuyzen-Goedkoop ◽

H G Hulshof ◽

A P J Van Dijk ◽

K P George ◽

...

Keyword(s):

Exercise Training ◽

Elite Athlete ◽

Left Ventricular ◽

Cardiac Remodelling ◽

Physiological Adaptation ◽

Training Volume ◽

Short Term ◽

Apical Rotation ◽

Elite Rowers ◽

The Impact

Abstract Funding Acknowledgements No financial support Background Chronic exercise training leads to cardiac remodelling; the so-called Athlete’s Heart. Previous studies are often limited by a cross-sectional design whilst longitudinal training studies are often constrained to the assessment of non-athletes. Echocardiography provides comprehensive assessment of mechanics and may give additional insight into short-term changes in training volume in the elite athlete. Purpose To examine the impact of a short-term (9 months) increase in training volume on cardiac structure and mechanics in elite international competing rowers. Methods As part of the work-up to the 2012 Olympic Games, twenty-seven elite rowers (26.4 ± 3.7 years, 19 male) underwent baseline echocardiography prior to and post (9-months) a planned increase in training volume. Conventional echocardiographic indices including mechanics of all cardiac chambers were assessed. Results In response to increased training volume, there was a significant increase in left ventricular (LV) size (IVSd 9.2 ± 1.2 to 9.7 ± 1.1 mm, p = 0.001; PWd 8.3 ± 1.3 to 8.7 ± 1.4 mm, p = 0.013), LVIDd (56.5 ± 4.6 to 57.9 ± 4.2 mm, p = 0.001), and LVMi (90.2 ± 17.8 to 100.8 ± 17.1 g/m2, p = 0.000), see table. There was a significant increase in LV twist (9.2 ± 4.5 to 11.2 ± 4.7 °, p = 0.04; basal rotation -4.4 ± 3.1 to -4.5 ± 3.4 °, p = 0.84; apical rotation 5.8 ± 3.4 to 7.1 ± 3.7 °, p = 0.011), see figure, however, there were no changes in any other conventional indices of function or any other cardiac mechanics. There was a significant increase in left atrial (LA) volume (58.8 ± 15.2 to 65.3 ± 17.6 mm, p = 0.01) whilst no changes were observed in right heart structure. Conclusion An increase in exercise training volume in elite rowers across 9-months induced mild balanced structural remodelling of the LV and LA with a concomitant increase in LV twist. Contradictory to findings in non-athletes, there was no increase in right ventricular or atrial structure or function which may be representative of the elite athlete status and possibly already at threshold for physiological adaptation. Abstract P784 Figure.

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Effects of coupled pacing on cardiac performance during acute atrial tachycardia and fibrillation: an old therapy revisited for a new reason

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00393.2003 ◽

2003 ◽

Vol 285 (6) ◽

pp. H2630-H2638 ◽

Cited By ~ 6

Author(s):

Hirotsugu Yamada ◽

David O. Martin ◽

Kent A. Mowrey ◽

Neil L. Greenberg ◽

Don W. Wallick

Keyword(s):

Atrial Tachycardia ◽

Left Ventricular ◽

Cardiac Performance ◽

Ventricular Rate ◽

Atrial Pacing ◽

Stroke Work ◽

End Diastolic Volume ◽

Work Area ◽

Pressure Development ◽

Ventricular Activation

Atrial tachycardia (AT) and fibrillation (AF) result in rapid ventricular rates that are detrimental to optimal cardiac function. The purpose of this study was to determine whether the application of a coupled pacing (CP) regimen would improve ventricular function by decreasing the ventricular rate of mechanical contractions (VRMCs). We simulated AT by pacing either atrium at a rate that resulted in a rapid but regular ventricular rate in seven anesthetized dogs. AF was induced by increasing the atrial pacing rate until atrial activation did not follow the pacing. After the induction of either AT or AF, we applied CP after each intrinsic ventricular activation. We measured the VRMCs and left ventricular (LV) pressures and volumes via a pressure-conductance catheter. The marked reductions in VRMCs during CP resulted in increases in LV end-diastolic volume. The CP resulted in virtually no mechanical contractions, whereas the strength of contractions from the normal electrical activation increased. The increases in the positive LV rate of pressure development over time and LV ejection fraction during CP were the result of postextrasystolic potentiation. The average stroke work (area of the pressure-volume loops) increased as a result of CP during both AT and AF. Despite the large increases in stroke volume (≅2×) during CP, the changes in cardiac output were moderate because the VRMCs markedly decreased (≅½). We conclude that CP therapy may be a viable therapy for slowing the heart rate and improving cardiac performance in patients with AT and AF.

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Abstract 3186: Right Ventricular Apical Pacing Impairs Left Ventricular Apical and Basal Rotation and Induces Apical-Basal Rotation Dyssynchrony

Circulation ◽

10.1161/circ.116.suppl_16.ii_716-a ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Ken Matsuoka ◽

Masami Nishino ◽

Masahiko Hara ◽

Shinpei Nakatani ◽

Akihito Hashimoto ◽

...

Keyword(s):

Right Ventricular ◽

Systolic Dysfunction ◽

Pacemaker Implantation ◽

Acute Effect ◽

Tissue Doppler ◽

Left Ventricular ◽

Doppler Imaging ◽

Apical Rotation ◽

Av Conduction ◽

Basal Rotation

Backgrounds: Although right ventricular apical (RVA) pacing has been reported to result in asynchronous patterns of left ventricular (LV) contraction reducing the LV ejection fraction (EF), LV torsion in RVA pacing has been unknown. We hypothesized that RVA pacing impairs rotation of LV apex and base and synchrony between LV apical and basal rotation, leading to the reduction of LV torsion. Methods: We studied 30 adult patients with sick sinus syndrome who had undergone DDD pacemaker implantation. Right ventricular pacing leads were positioned at the right ventricular apex. Changing from the intrinsic AV conduction to RVA pacing, we assessed the acute effect on echocardiac parameters; LV EF, tissue Doppler imaging (TDI) derived intraventricular delay, LV rotation and torsion, and LV apical-basal rotation dyssynchrony. Results: Results were shown in a table . Changing from the intrinsic AV conduction to RVA pacing, LV EF reduced (P=0.0003) and TDI derived intraventricular delay prolonged (P<0.0001). During RVA pacing, values of peak rotation in LV apex and LV base were significantly lower than those during intrinsic AV conduction (P=0.007 and 0.003, respectively). Correspondingly, LV torsion decreased significantly (P<0.0001). During the intrinsic AV conduction, LV apex and base rotated at the almost same time, while, during RVA pacing, LV basal rotation was delayed as compared to LV apical rotation. Consequently, apical-basal rotation dyssynchrony during RVA pacing was significantly longer than that during the intrinsic AV conduction (P=0.02). Conclusion: RVA pacing decreases LV rotation and torsion and induces LV apical-basal rotation dyssynchrony, resulting in partially LV systolic dysfunction. Comparison between Intrinsic AV Conduction and RVA Pacing

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Left Ventricular Apical Rotation, but Not Basal Rotation is Impaired in Patients with Dilated Cardiomyopathy

Journal of Cardiac Failure ◽

10.1016/j.cardfail.2005.08.225 ◽

2005 ◽

Vol 11 (9) ◽

pp. S292 ◽

Cited By ~ 2

Author(s):

Eizo Akagawa ◽

Kazuya Murata ◽

Hideki Kunichika ◽

Yasuyuki Hadano ◽

Nobuaki Tanaka ◽

...

Keyword(s):

Dilated Cardiomyopathy ◽

Left Ventricular ◽

Apical Rotation ◽

Basal Rotation

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Dissecting myocardial mechanics in patients with severe aortic stenosis: 2-dimensional vs 3-dimensional-speckle tracking echocardiography

10.21203/rs.2.14188/v3 ◽

2020 ◽

Author(s):

Xiaojun Bi ◽

Darwin F Yeung ◽

Husam M. Salah ◽

Maria C. Arciniegas Calle ◽

Jeremy J. Thaden ◽

...

Keyword(s):

Aortic Stenosis ◽

Speckle Tracking ◽

Speckle Tracking Echocardiography ◽

Normal Values ◽

Left Ventricular ◽

3 Dimensional ◽

Arterial Impedance ◽

Apical Rotation ◽

2D And 3D ◽

The Impact

Abstract Background: Aortic stenosis (AS) causes left ventricular (LV) pressure overload, leading to adverse LV remodeling and dysfunction. Identifying early subclinical markers of LV dysfunction in patients with significant AS is critical as this could provide support for earlier intervention, which may result in improved long-term outcomes. We therefore examined the impact of severe AS and its consequent increase in LV afterload on myocardial deformation and rotational mechanics by 2-dimensional (2D) and 3-dimensional (3D) speckle-tracking echocardiography. Methods: We prospectively measured various strain parameters in 168 patients (42% female, mean age 72±12 years) with severe AS and LV ejection fraction (EF) ≥50%, and compared them to normal values found in literature. 2D and 3D images were analyzed for global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), basal rotation, apical rotation, and peak systolic twist. We further assessed the degree of concordance between 2D and 3D strain, and examined their association with measures of LV preload and afterload. Results: Patients with severe AS exhibited significantly lower GLS and GRS but higher GCS, apical rotation, and twist by 2D and 3D echocardiography compared with published normal values (P=0.003 for 3D twist,P<0.001 for all others). Agreement between 2D- and 3D-GLS by concordance correlation coefficient was 0.49 (95% confidence interval: 0.39-0.57). GLS was correlated with valvulo-arterial impedance, a measure of LV afterload (r=0.34, p<0.001 and r=0.23, p=0.003, respectively). Conclusion: Patients with severe AS demonstrated lower-than-normal GLS and GRS but appear to compensate with higher-than-normal GCS, apical rotation, and twist in order to maintain a preserved LVEF. GLS showed a modest correlation with valvulo-arterial impedance.

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P333 Left ventricular rotational abnormalities in hypereosinophilic syndrome as assessed by three-dimensional speckle-tracking echocardiography

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jez319.186 ◽

2020 ◽

Vol 21 (Supplement_1) ◽

Author(s):

A Nemes ◽

A Kormanyos ◽

I Marton ◽

P Domsik ◽

A Kalapos ◽

...

Keyword(s):

Speckle Tracking ◽

Speckle Tracking Echocardiography ◽

Hypereosinophilic Syndrome ◽

Three Dimensional ◽

Organ Damage ◽

Left Ventricular ◽

Diagnostic Methods ◽

Control Group ◽

Apical Rotation ◽

Basal Rotation

Abstract Introduction Hypereosinophilic syndrome (HES) is a very heterogeneous group of disorders with varied etiologies characterized by peripheral eosinophilia and eosinophilic tissue/end-organ damage. In the present study, the ability of a novel non-invasive clinical tool, three-dimensional speckle-tracking echocardiography (3DSTE) was investigated to reveal any change in left ventricular (LV) rotational mechanics in clinically asymptomatic HES patients without manifest organ damage as determined by conventional diagnostic methods. Methods The present study comprised 13 patients established diagnosis of HES. However, one patient with idiopathic HES has been excluded due to insufficient image quality. The remaining patient population contained 11 cases with idiopathic HES and one patient with acute T-lymphoma associated HES (mean age: 59.7 ± 13.7 years, 8 males). The control group consisted of 36 healthy volunteers (mean age: 52.9 ± 8.3 years, 23 males). All HES patients and controls underwent complete two-dimensional Doppler echocardiography and 3DSTE. Results Both LV apical rotation (4.86 ± 1.92 degree vs. 10.07 ± 3.92 degree, p < 0.0001) and LV twist (8.52 ± 2.79 degree vs. 14.41 ± 4.26 degree, p < 0.0001) showed significant deteriotations in most of HES patients. In 2 subjects absence of LV twist called as LV „rigid body rotation’ (RBR) was detected. One patient had 1.77 degree counterclockwise (abnormally directed) LV basal rotation and 14.29 degree counterclockwise (normally directed) LV apical rotation resulting in 12.59 degree LV apico-basal gradient. The other patient had normally directed -2.09 degree LV basal rotation and almost zero (-0.27 degree) LV apical rotation resulting in 1.82 degree LV apico-basal gradient. Conclusions Reduced LV apical rotation and twist could be demonstrated in HES. LV-RBR could be detected in some HES patients.

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Comparison of left ventricular rotational mechanics between term and extremely premature infants over the first week of age

Open Heart ◽

10.1136/openhrt-2020-001458 ◽

2021 ◽

Vol 8 (1) ◽

pp. e001458

Author(s):

Aisling Smith ◽

Neidin Bussmann ◽

Phillip Levy ◽

Orla Franklin ◽

Naomi McCallion ◽

...

Keyword(s):

Preterm Infants ◽

Premature Infants ◽

Left Ventricular ◽

Strong Positive Correlation ◽

Term Infants ◽

Time Points ◽

Apical Rotation ◽

Extremely Preterm ◽

Basal Rotation ◽

Rotational Mechanics

ObjectiveLeft ventricle (LV) rotational mechanics is an emerging tool to characterise LV function, but warrants further evaluation in neonates. The aim of this study was to compare LV rotational mechanics between term and extremely preterm babies over the first week of age.MethodsIn this prospective study, we serially assessed LV rotational parameters in 50 term infants and compared them with a historical dataset of 50 preterm infants born <29 weeks gestation. LV basal and apical rotation, LV twist, LV twist/untwist rate and torsion were derived using two-dimensional speckle tracking echocardiography at three time points over the first week of age.ResultsThere was no change in LV twist, LV torsion, basal rotation or apical rotation in term infants over the study period (all p>0.05). LV twist and torsion were higher in preterm infants, and increased over time. In preterm infants, basal rotation evolved from anticlockwise to clockwise rotation. Apical rotation remained anticlockwise in both groups (all p>0.05). LV twist rate (LVTR) and untwist rate was higher in preterm infants and increased over the three time points (all p>0.05). There was a strong positive correlation between LV torsion and LV untwist rate (LVUTR) in the entire cohort during the third scan.ConclusionTerm infants exhibit minimal LV twist which remains unchanged over the first week of age. This is in contrast to premature infants who demonstrate increasing indices of twist, torsion, LVTR and LVUTR over the first week, likely as a compensatory mechanism for reduced LV compliance.

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