End-systolic Wall Thickness Research Articles

Myocardial viability under various ischemic burdens in chronic total occlusions: A stress-cardiac magnetic resonance study

ObjectivesThis study aimed to analyze each myocardial segment's ischemic burden, scarring, function, and viability by late gadolinium enhancement (LGE) imaging and stress-MRI using adenosine. Materials and methodsSemi-quantitative and qualitative parameters of myocardial segments were obtained by stress-MRI. Moreover, segments without perfusion defect were defined as the no ischemic group, segments with a perfusion defect of ≤50% were defined as a low ischemic burden group, and segments with a perfusion defect of >50% were defined as a high ischemic burden group. “Segmental wall thickening (SWT)” was defined as the absolute difference between the end-diastolic and end-systolic wall thickness. Finally, viability was defined by dysfunctional myocardium (<3 ​mm segmental wall thickening [SWT]) and ≤50% late gadolinium enhancement (LGE). ResultsA total of 445 segments in the CTO territory were analyzed, scar tissue was found in the CTO territory, with LGE evident in 18.2% of CTO segments totaling >50%. Among the different ischemic burden groups, there were significant differences in LGE volume (p ​< ​0.01), and the trend of SWT was consistent with the degree of myocardial ischemia. The incidence of ≤50% LGE and viable myocardium was higher in segments of the no ischemia and low ischemic burden groups. However, there was no significant difference in the incidence of dysfunctional myocardial segments among the three groups (P ​> ​0.05). ConclusionsStress MRI parameters can accurately and detailly assess myocardial viability and function, so multi-parameter joint assessment of CTO patients by stress MRI may help in treatment decisions.

Preconditioning with selective autoretroperfusion: In vivo and in silico evidence of washout hypothesis.

Prompt reperfusion of coronary artery after acute myocardial infarction (AMI) is crucial for minimizing heart injury. The myocardium, however, may experience additional injury due to the flow restoration itself (reperfusion injury, RI). The purpose of this study was to demonstrate that short preconditioning (10min) with selective autoretroperfusion (SARP) ameliorates RI, based on a washout hypothesis. AMI was induced in 23 pigs (3 groups) by occluding the left anterior descending (LAD) artery. In SARP-b (SARP balloon inflated) and SARP-nb (SARP balloon deflated) groups, arterial blood was retroperfused for 10min via the great cardiac vein before releasing the arterial occlusion. A mathematical model of coronary circulation was used to simulate the SARP process and evaluate the potential washout effect. SARP restored left ventricular function during LAD occlusion. Ejection fraction in the SARP-b group returned to baseline levels, compared to SARP-nb and control groups. Infarct area was significantly larger in the control group than in the SARP-b and SARP-nb groups. End-systolic wall thickness was preserved in the SARP-b compared to the SARP-nb and control groups. Analyte values (pH, lactate, glucose, and others), measured every 2min during retroperfusion, suggest a "washout" effect as one important mechanism of action of SARP in reducing infarct size. With SARP, the values progressively approached baseline levels. The mathematical model also confirmed a possible washout effect of tracers. RI can be ameliorated by delaying restoration of arterial flow for a brief period of time while pretreating the infarction with SARP to restore homeostasis via a washout mechanism.

Cornus officinalis Sieb. et Zucc. Alleviates Mitochondrial Abnormalities and Heart Failure through AMPK

Background: Traditional Chinese medicine (TCM) has clear advantages in stabilizing patients with heart failure (HF) and improving cardiac functions. Aims: This study aimed to investigate the role of Cornus officinalis Sieb. et Zucc. (Cor) in HF. Settings and Design: Rats with HF were treated with Cor or Cor with an adenosine monophosphate-activated protein kinase (AMPK) inhibitor, dorsomorphin dihydrochloride (Dor). Materials and Methods: The weight and echocardiography findings of the rats were examined. AMPK and p-AMPK expression levels were assessed using Western blots, mitochondrial changes were evaluated using transmission electron microscopy (TEM), and adenosine triphosphate (ATP) levels were detected in each group. Finally, the targets of Cor were analyzed using HERB ( http://herb.ac.cn ). Statistical Analysis Used: A Student’s t-test was used to compare two groups, and a one-way analysis of variance was performed for intergroup comparison. A p &lt; 0.05 indicated that the difference was statistically significant. Results: Compared with that of the Sham group, the body weight of the Model group decreased; left ventricular end diastolic diameter (LVIDd) and left ventricular end systolic diameter (LVIDs) increased; and left ventricular end diastolic posterior wall thickness (LVPWd), left ventricular end systolic posterior wall thickness (LVPWs), left ventricular ejection fraction (EF), and stroke volume (SV) decreased. These effects were reversed by the Cor treatment. Western blot analysis indicated p-AMPK levels were higher in the Model group than those in the Sham group. After Cor treatment, p-AMPK levels increased but later decreased after treatment with Dor. In addition, myocardial mitochondrial abnormalities were reduced and ATP levels increased in the Cor group compared with the Model group, which were reversed by Dor. Lastly, Cor was found to target AMPK pathway-related genes. Conclusion: Cor exerts protective effects on HF by activating AMPK to improve mitochondrial function.

Abstract 13978: Biologic versus Imaging Markers Predicting Readmission and Death in Heart Failure With Preserved Ejection Fraction

Introduction: Increased B-type Natriuretic Peptide (NT-proBNP) levels have been associated with adverse outcomes in patients with heart failure with preserved ejection fraction (HFpEF). Global longitudinal strain (GLS) and wall stress (WS) are frequently reported to be abnormal in these patients as well, but studies examining how structural changes in those with HFpEF affect morbidity and mortality have been scarce. Hypothesis: NT-proBNP is a stronger predictor of death and heart failure readmissions in HFpEF patients when compared to GLS and WS. Methods: We conducted a retrospective study of 237 patients admitted with acute decompensated heart failure, all with EF &gt; 50. Average age was 78 + 11, 69% of patients were female, and average BMI was 29 + 13. GLS was measured using speckled tracing echocardiography and WS was calculated from systolic blood pressure, end-systolic left ventricular (LV) dimension, and end-systolic posterior wall thickness. Results: During a follow-up period of 2 years, 55 patients died and 55 were readmitted with the diagnosis of acute decompensated heart failure. Mean NT-proBNP among all patients was 9982 + 16268, mean GLS -17.84 + 4.52, and mean WS was 52.27 + 25.23. 129 patients had an abnormal or borderline GLS of &gt;-18, whereas nearly all patients (230) had an abnormal WS of &lt;109. (See table for results.) Conclusion: GLS and WS are reduced in a significant proportion of HFpEF patients. However, our data suggests that compared to echocardiographic indices of LV systolic function, biomarkers have a stronger short-term prognostic value.

Transthoracic Echocardiography to Assess Post-Resuscitation Left Ventricular Dysfunction After Acute Myocardial Infarction and Cardiac Arrest in Pigs

One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, approximately 70% of patients die before hospital discharge due to post-resuscitation myocardial and cerebral dysfunction. In experimental models, myocardial dysfunction after cardiac arrest, characterized by an impairment in both left ventricular (LV) systolic and diastolic function, has been described as reversible but very little data are available in cardiac arrest models associated with AMI in pigs. Transthoracic echocardiography is the first-line diagnostic test for the assessment of myocardial dysfunction, structural changes and/or AMI extension. In this pig model of ischemic cardiac arrest, echocardiography was done at baseline and 2-4 and 96 hours after resuscitation. In the acute phase, the examinations are done in anesthetized, mechanically ventilated pigs (weight 39.8 ± 0.6 kg) and ECG is recorded continuously. Mono- and bi-dimensional, Doppler and tissue Doppler recordings are acquired. Aortic and left atrium diameter, end-systolic and end-diastolic left ventricular wall thicknesses, end-diastolic and end-systolic diameters and shortening fraction (SF) are measured. Apical 2-, 3-, 4-, and 5-chamber views are acquired, LV volumes and ejection fraction are calculated. Segmental wall motion analysis is done to detect the localization and estimate the extent of myocardial infarction. Pulsed Wave Doppler echocardiography is used to record trans-mitral flow velocities from a 4-apical chamber view and trans-aortic flow from a 5-chamber view to calculate LV cardiac output (CO) and stroke volume (SV). Tissue Doppler Imaging (TDI) of LV lateral and septal mitral anulus is recorded (TDI septal and lateral s', e', a' velocities). All the recordings and measurements are done according to the recommendations of the American and European Societies of Echocardiography Guidelines.

Association between myocardial wall thickness and left ventricular functional recovery after catheter ablation of atrial fibrillation in patients with reduced ejection fraction

Abstract Background Catheter ablation of atrial fibrillation (AFCA) is an effective treatment to develop left ventricular (LV) functional recovery. However, the degree of recovery differs between individuals due to the different extent of myocardial fibrosis and scarring. Purpose To examine whether pre-ablation LV wall thickness (WT) and its regional heterogeneity predict LV functional recovery after AFCA in patients with LV systolic dysfunction. Methods Of 3682 consecutive patients who underwent first-time AFCA between January 2012 and September 2020 in our institution, 174 (age, 63±10 years; male, 83%; ischemic cardiomyopathy, 14%) with a baseline LV ejection fraction (LVEF) of &amp;lt;40% were retrospectively evaluated. They were subjected to 256-slice MDCT scanning at baseline and 3 months after AFCA. Baseline WT was evaluated by 16-segment model. Mean and standard deviation (SD) of 16 regional WT were calculated in both end-systolic and end-diastolic phase. Results LVEF significantly improved from 30±7% to 57±17% (p&amp;lt;0.001) after AFCA. Increase in LVEF (delta-LVEF) was positively correlated with baseline end-diastolic WT (r=0.31, p&amp;lt;0.001) and negatively correlated with SD of end-systolic WT (r=−0.21, p=0.007). Independent of WT measurements, delta-LVEF was negatively correlated with LV end-diastolic volume (r=−0.42, p&amp;lt;0.001). We created a scoring system to predict the degree of wall motion recovery using the median value of the 3 variables; assigned 1 point each for end-diastolic WT &amp;gt;7.4mm, SD of end-systolic WT &amp;lt;1.61mm, and LV end-diastolic volume &amp;lt;125ml. The model successfully predicted improvement in LVEF after AFCA (0 point (N=13) vs. 1 point (N=72) vs. 2–3 point (N=89), 11±16% vs. 20±17% vs. 33±12%, p&amp;lt;0.001). Conclusion Myocardial WT and its regional heterogeneity as well as LV end-diastolic volume predicted functional recovery after AFCA in patients with reduced LVEF. Funding Acknowledgement Type of funding sources: None.

Association of smoking with indicators of the structure and function of left ventricle of the heart in middle-aged men

Aim. Evaluation of the association of smoking (status, intensity and duration) with indicators of the structure and function of the left ventricle of the heart in a sample of middle-aged men.Material and methods. This study is part of a 32-year prospective cohort observation of men from childhood (11-12 years). 301 (30.0%) representatives of the original population sample aged 41-44 years were included in the study. The examination included a survey on intensity of smoking, anthropometry, measuring blood pressure, pulse rate, echocardiography, and blood lipid analysis.Results. 301 men aged 41-44 included 92 (30.6%) men who had never smoked, 73 (24.3%) men smoked in the past and 136 (45.2%) men currently smoke. 75% of current smokers started smoking before age 19, of which 32.3% started smoking before age 15. The duration of smoking cessation among former smokers was 14.4 (12.5; 16.2) years. The average duration of smoking [average (95% confidence interval)] among former smokers was 14.4 (12.5; 16.2), for current smokers – 25.3 (24.6; 26.0) years. Current smoking was statistically significantly associated with higher mean values of the left ventricular myocardium mass (LVMM), the left ventricular myocardial mass index (LVMMI), the end-systolic and end-diastolic interventricular septum thickness (IVSTs/IVSTd), the end-systolic left ventricular posterior wall thickness (LVPWs), and the intensity and duration of current smoking were associated with higher values of the relative wall thickness of the left ventricle, the end-diastolic interventricular septum thickness, the end-systolic interventricular septum thickness, and with low values of the left ventricular stroke volume index (LV SVI). Multiple regression analysis showed that current smoking has an independent effect on the left ventricular myocardium mass, the left ventricular myocardial mass index and the end-diastolic interventricular septum thickness, and the duration and intensity of smoking has an effect on the index of the left ventricular stroke volume index.Conclusion. Current smoking, duration and intensity in middle-aged men is associated with unfavorable changes in indicators of the structure and function of the left ventricle of the heart. Efforts for primary prevention of smoking should begin as early as childhood and continue into adolescence and young adulthood.

An Optimized Model of Hypertrophic Preconditioning Confers Cardioprotection in the Mouse

BackgroundConventional models of hypertrophic preconditioning (C-HP) can be established surgically through transverse aortic constriction (TAC) → deconstriction (De-TAC) → reconstriction (Re-TAC) characterized by dynamic afterload while it exerts technical difficulty on operators and poses high mortality during perioperative period in mice. We aimed to introduce an optimized method for obtaining a hypertrophic preconditioning (O-HP) model for further study on cardiac hypertrophy. MethodsNinety mice were divided into four groups: sham, TAC, C-HP, and O-HP. The sham group was exerted on three-time thoracotomies. The TAC group experienced twice thoracotomies and one TAC operation. C-HP and O-HP groups were given TAC, De-TAC, and Re-TAC operation at day 0, day 3, and day 7 in conventional and optimized method, respectively. We optimized the operating procedure in O-HP mice compared with the C-HP group by (1) leaving a ∼3-cm suture fixed in the subcutaneous layer after aortic constriction in TAC surgery (2) using two small forceps to untie the constriction knot instead of cutting it in the De-TAC operation. Ultrasound biomicroscopy was used for hemodynamics and cardiac function detection. Four weeks after the third surgery, all mice were sacrificed and pathology was analyzed among four groups. ResultsFour weeks after Re-TAC, the survival of O-HP mice was 63.3% while that of C-HP was 26.7%. Ultrasound biomicroscopy showed a successful establishment of HP models. C-HP and O-HP mice had improved cardiac structure and function indicated by left ventricular end-systolic diameter, left ventricular end-systolic posterior wall thickness, left ventricular ejection fraction, and left ventricular fractional shortening than the TAC group. Pathological analysis showed O-HP as well as C-HP had less hypertrophy than the TAC mice. ConclusionsOur results provide a rapid, safe, efficient, and reproducible method for optimized establishment of the HP model, which will facilitate studies for early intervention and prevention of left ventricular hypertrophy and heart failure.

Assessment of Structure, Function, and Rhythm of the Heart with Echocardiography and Electrocardiography in Adolescent Swimmers.

The aim of this study was to evaluate the cardiac parameters by using electrocardiography and echocardiography in adolescent swimmers. Twenty-two adolescent swimmers and 22 gender- and age-matched sedentary controls admitted to our center between November 2018 and May 2019 were included in this study. In addition to demographical characteristics, participants were assessed via a 12-lead electrocardiography and two-dimensional echocardiography for cardiac function. On the echocardiography, end-systolic and end-diastolic interventricular septum, end-systolic and end-diastolic left ventricular posterior wall thicknesses, left atrial width, Tricuspid E, left ventricular mass and left ventricular mass index were higher in the swimmers when compared to the sedentary controls (P < 0.05). On the electrocardiography, Tp-e duration which reflects ventricular transmural repolarization, and Tp-e/QT and Tp-e/corrected QT ratios were higher in the swimmers than the sedentary controls (P < 0.05). In conclusion, swimming exercise in children leads to concentric thickening of left ventricle and induces an increase in Tp-e duration, and Tp-e/QT and Tp-e/corrected QT ratios, which are the novel markers for risk of ventricular arrhythmias.

The regulatory mechanism of Raf/MEK/ERK pathway on the rat cardiac hypertrophy induced by transverse aortic constriction

To investigate the mRNA, protein expression levels and the phosphorylation levels of key factors in rapidly accelerated fibrosarcoma/mitogen-activated protein kinase kinase/extracellular regulated protein kinases (Raf/MEK/ERK) pathway, and to clarify the regulatory function of Raf/MEK/ERK pathway in myocardial hypertrophy. Twenty SD rats were divided into sham-operated group and model group. The myocardial hypertrophy model was established by transverse aortic constriction (TAC). At 12 weeks after TAC, blood samples were collected from the submandibular vein, and the serum was separated to detect the content of N terminal pro B type natriuretic peptide (NT-proBNP). After that, the rats were subjected to echocardiography and hemodynamic measurement. Then the pathological changes of myocardial tissue were observed. And the levels of mRNA, protein expression and the phosphorylation of key factors in Raf/MEK/ERK pathway were detected in myocardial tissue. Compared with sham-operated group, left ventricular end-diastolic interventricular septal thickness (IVSd), left ventricular end-systolic interventricular septal thickness (IVSs), left ventricular end-diastolic posterior wall thickness (LVPWd) and left vebtricular end-systolic posterior wall thickness (LVPWs) in TAC model group were increased significantly (P＜0.05,P＜0.01), left ventricular end-systolic diameter (LVIDs) was decreased significantly (P＜0.01), LV Mass and LW(LV Mass/Weight)were increased significantly (P＜0.05, P＜0.01). The levels of heart rate (HR), left ventricular pressure maximal rate of rise (+dp/dtmax), left ventricular pressure maximal rate of fall (-dp/dtmax) were decreased significantly (P＜0.01). The serum level of NT-proBNP in TAC rat was increased significantly (P＜0.01). The myocardial cells in TAC model group were arranged disorderly, myocardial cell hypertrophy, cytoplasm were increased significantly, and inflammatory cells infiltrated. A large amount of collagen fibers were deposited and large area of myocardial cells were stained blue in TAC rat. The expression levels of phospho-c-Raf (Ser259) and phospho-c-Raf (Ser338) in myocardial tissue were significantly increased (P＜0.01), meanwhile the expression levels of phospho- MEK1/2(Ser217/Ser221) and phospho-ERK1/2 (Thr202/Tyr204) were also significantly increased (P＜0.01). The regulatory role of Raf / MEK / ERK pathway in cardiac hypertrophy may be through the activation of phosphorylation of c-raf, MEK1, Mek2, ERK1 and ERK2 at specific sites.

Reference Ranges for Left Ventricular Curvedness and Curvedness-Based Functional Indices Using Cardiovascular Magnetic Resonance in Healthy Asian Subjects

Curvature-based three-dimensional cardiovascular magnetic resonance (CMR) allows regional function characterization without an external spatial frame of reference. However, introduction of this modality into clinical practice is hampered by lack of reference values. We aim to establish normal ranges for 3D left ventricular (LV) regional parameters in relation to age and gender for 171 healthy subjects. LV geometrical reconstruction and automatic calculation of regional parameters were implemented by in-house software (CardioWerkz) using stacks of short-axis cine slices. Parameter normal ranges were stratified by gender and age categories (≤44, 45–64, 65–74 and 75–84 years). Our software had excellent intra- and inter-observer agreement. Ageing was significantly associated with increases in end-systolic (ES) curvedness (CES) and area strain (AS) with higher rates of increase in males, end-diastolic (ED) and ES wall thickness (WTED, WTES) with higher rates of increase in females, and reductions in ED and ES wall stress indices (σi,ED) with higher rates of increase in females. Females exhibited greater ED curvedness, CES, σi,ED and AS than males, but smaller WTED and WTES. Age × gender interaction was not observed for any parameter. This study establishes age and gender specific reference values for 3D LV regional parameters using CMR without additional image acquisition.

Echocardiographic Findings in a Cohort of Perinatally HIV-Infected Adolescents Compared with Uninfected Peers from the Cape Town Adolescent Antiretroviral Cohort

Little is known about the cardiac health of perinatally HIV-infected (PHIV+) adolescents on antiretroviral therapy (ART) in sub-Saharan Africa. The authors examined cardiac structure and function in PHIV+adolescents on ART compared with HIV-uninfected (HIV-) adolescents. Echocardiography was performed on PHIV+ and age- and sex-frequency-matched HIV- adolescents enrolled in the Cape Town Adolescent Antiretroviral Cohort. Participants were eligible if they were 9 to 14years of age and had been on ART for ≥6months. Overall, 474 PHIV+adolescents (median age, 12years; 51% boys; mean age at ART initiation, 5years) and 109 HIV- adolescents (median age, 11.8years; 45% boys) were included. The mean duration on ART was 7years, with 37% starting treatment before 2years of age. Compared with HIV- adolescents, PHIV+adolescents had higher median Z scores for left ventricular (LV) internal end-diastolic dimension, LV end-systolic posterior wall thickness, and end-systolic interventricular septal thickness. PHIV+adolescents had a lower median Z score for right ventricular internal end-diastolic dimension as compared with HIV- adolescents. There was no difference in ejection fraction or diastolic function between groups. Later initiation of ART (after 6years) was associated with increased risk for LV hypertrophy (odds ratio, 2.9; 95% CI, 1.3-6.6; P=.01) compared with those who started ART earlier. PHIV+adolescents with World Health Organization stage IV HIV infection were at increased risk (odds ratio, 2.2; 95% CI, 1.0-4.6; P=.05) of having LV diastolic dysfunction compared with those with less advanced clinical disease. This study revealed subtle differences in echocardiographic parameters between PHIV+ and HIV- adolescents. Although these were not clinically significant, starting ART at an older age was a significant risk factor for LV hypertrophy, while more advanced clinical disease was associated with LV diastolic dysfunction.

Echocardiographic Evaluation of Females with Asthma

Objective: To evaluate ventricular functions and atrial conduction times in females with mild-to-moderate asthma Design: Prospective cohort study Place &amp; duration of the study: Kars Harakani State Hospital, Department of Respiratory Diseases, March to August 2019 Methodology: One hundred and sixteen patients with mild-to-moderate asthma and fifty healthy subjects enrolled. Basic characteristics, blood variables and echocardiographic parameters were compared between two groups. Results: CRP (p=0.017), CAR (p=0.01), eosinophil count (p=0.001) were higher and albumin (p=0.001) was lower in the asthma group. End-systolic diameter (p=0.029), interventricular septum thickness (p=0.022) and posterior wall thickness (p=0.027) were higher in the group with asthma. Emax (p=0.040) and E/A mitral (p=0.040) decreased in asthmatic females. Aortic diameters consist of sinus (p=0.041), sinutubular junction (p=0.037) and ascending aorta (p=0.006) increased significantly and lateral/tricuspid AEMD prolonged (p=0.038) in the patients with asthma. In the asthma group, RV free wall thickness was higher (p=0.043). Conclusion: LV end-systolic diameter, wall thickness, diastolic functions, aortic diameters, lateral/tricuspid AEMD and RV free wall thickness were affected by asthma in females. Key words: asthma, females, echocardiography Special Issue of Health Sciences DOI: 10.7176/JSTR/6-03-06

Left ventricular myocardial remodeling in dogs with mitral valve endocardiosis.

Background and Aim:Left ventricular myocardial remodeling could play an important role in the progression of chronic heart failure (CHF) syndrome in dogs with mitral valve endocardiosis. The aim of this study was to evaluate the left ventricular myocardial remodeling in dogs with mitral valve endocardiosis and to study the dependence of the incidence of this pathological phenomenon on the functional class (FC) of progression of the CHF syndrome.Materials and Methods:A total of 108 afflicted dogs and 36 clinically healthy dogs were examined using transthoracic echocardiography. The following structural and geometric parameters of the left ventricular remodeling were evaluated: Myocardial mass and its index, sphericity index at the end of systole and diastole, end-systolic and end-diastolic relative wall thickness, and integral remodeling index.Results:In all clinically healthy dogs, a normal type of the left ventricular chamber geometry was revealed, whereas, in dogs with mitral valve endocardiosis, the normal geometry of the left ventricle occurred in 56.4%, eccentric hypertrophy in 24.1%, concentric remodeling in 10.2%, and concentric hypertrophy in 9.3% of the cases. In patients with endocardiosis, there was no dilatation type of cardiac remodeling observed.Conclusion:When compared to the clinically healthy animals, the dogs with mitral valve endocardiosis presented with indicators of structural and geometric remodeling, such as increased myocardial mass, myocardial mass index, and sphericity index at the end of systole and diastole, as well as relatively reduced integral systolic index of remodeling and systolic relative thickness of the walls of the heart. The parameters of the left ventricular myocardial remodeling correlated significantly with the FC of CHF syndrome.

Acupuncture at PC6 prevents cardiac hypertrophy in isoproterenol-treated mice.

To investigate the effect of acupuncture at PC6 on cardiac hypertrophy in isoproterenol (ISO)-treated mice. 48 male C57BL/6 mice underwent subcutaneous injection of ISO for 14 days and were randomly divided into four groups (n=12 each) that remained untreated (ISO group), received verum manual acupuncture (MA) treatment at PC6 (ISO+MA(PC6) group), sham MA at location on the tail not corresponding to any traditional acupuncture point (ISO+MA(tail) group), or propranolol (ISO+PR group). An additional 12 mice were given an injection of phosphate-buffered saline (PBS) and formed a healthy control (Normal) group. After performing echocardiography and measuring the ratio of heart weight (HW)/tibia length (TL) at 14 days, all mice were euthanased. Morphological examination was performed following haematoxylin and eosin and Masson's staining of heart tissues. Ultrastructural changes were observed by electron microscopy. Cardiac protein expression of atrial natriuretic peptide (ANP) and tumour necrosis factor α (TNFα) were measured by immunohistochemical (IHC) staining and Western blotting. Compared with the untreated model group, acupuncture at PC6 lowered the heart rate, reduced the ratio of HW/TL, improved the left ventricular (LV) anterior wall thickness (LVAWd), LV end-diastolic anterior wall thickness (LVAWs), LV end-systolic posterior wall thickness (LVPWd), LV end-diastolic posterior wall thickness (LVPWs), and fractional shortening (FS) as observed by echocardiography (ISO+MA(PC6) vs. ISO groups: P<0.05). Moreover, evidence from morphological studies demonstrated that acupuncture at PC6 inhibited myocardial hypertrophy and collagen deposition, and normalised the ultrastructural changes. In addition, ANP and TNFα expression were attenuated in the verum acupuncture group compared with the untreated model group (ISO+MA(PC6) vs. ISO groups: P<0.05). The results demonstrated that acupuncture at PC6 attenuates sympathetic overactivity. Additionally, it may improve cardiac performance by reversing adverse cardiac remodelling. Acupuncture has potential as a treatment for sympathetic hypertension.

Association between hippuric acid and left ventricular hypertrophy in maintenance hemodialysis patients

BackgroundLeft ventricular hypertrophy (LVH) is one of the most common cardiac abnormalities in patients with end-stage renal disease. Hippuric acid (HA), a harmful uremic toxin, is known to be elevated in patients with uremia, and serum HA levels are associated with neurological symptoms, metabolic acidosis, and accelerated renal damage associated with chronic kidney disease. However, the pathophysiological role of HA in patients with uremia remains unclear. We investigated the association between serum HA levels and echocardiographic measurements in patients undergoing hemodialysis (HD) treatment. MethodsEighty consecutive patients treated at a single HD center (44 males, 36 females; mean age 66 y, mean HD duration 6 y) were included in this study. Comprehensive echocardiography was performed after HD. Blood samples were obtained before HD. ResultsPearson's correlation analysis revealed that serum HA levels were positively correlated with diastolic blood pressure, serum creatinine, left ventricular mass index, end diastolic interventricular septal thickness, left ventricular end-diastolic diameter, left ventricular end systolic diameter, end systolic left ventricular posterior wall thickness, and left atrium diameter, and negatively correlated with age. Furthermore, the HD patients with LVH had higher median serum HA levels than those without LVH (34.2 vs. 18.1 μg/ml, p = 0.003). Multiple logistic regression analysis revealed that HA was independently associated with LVH even after adjusting for known biomarkers. Moreover, the receiver operator characteristics curve of HA showed that a HA level of >26.9 μg/ml was associated with LVH. ConclusionsHA was significantly associated with LVH. HA could be a novel biomarker of left ventricular overload, which is closely associated with an increased risk of death in HD patients.

Left Ventricle Function During Therapeutic Hypothermia with Beta1-Adrenergic Receptor Blockade.

Therapeutic hypothermia is an established treatment in patients resuscitated from cardiac arrest. It is usually well-tolerated circulatory, but hypothermia negatively effects myocardial contraction and relaxation velocities and increases diastolic filling restrictions. A significant proportion of resuscitated patients are treated with long-acting beta-receptor blocking agents' prearrest, but the combined effects of hypothermia and beta-blockade on left ventricle (LV) function are not previously investigated. We hypothesized that beta1-adrenergic receptor blockade (esmolol infusion) exacerbates the negative effects of hypothermia on active myocardial motions, affecting both systolic and diastolic LV function. A pig (n = 10) study was performed to evaluate the myocardial effects of esmolol during hypothermia (33°C) and during normothermia, at spontaneous and pacing-increased heart rates (HRs). LV function was assessed by a LV pressure transducer, an epicardial ultrasonic transducer (wall thickness, wall thickening/thinning velocity) and an aortic ultrasonic flow-probe (stroke volume, cardiac output). The data were compared using a paired two-tailed Students t-test, and also analyzed using a linear mixed model to handle dependencies introduced by repeated measurements within each subject. The significance level was p ≤ 0.05. The effects of hypothermia and beta blockade were distinct and additive. Hypothermia reduced myocardial motion velocities and increased diastolic filling restrictions, but end-systolic wall thickness increased, and stroke volume and dP/dtmax (pumping function) were maintained. In contrast, esmolol predominantly affected systolic pumping function, by a negative inotropic effect. In combination, hypothermia and esmolol reduced myocardial velocities in systole and diastole by ∼40%, compared with normothermia without esmolol, inducing in combination both systolic and diastolic LV function impairment. The cardiac dysfunction deteriorated at increased HRs during hypothermia. Beta1-adrenergic receptor blockade (esmolol) exacerbates the negative effects of hypothermia on active myocardial contraction and relaxation. The combination of hypothermia with beta-blockade induces both systolic and diastolic LV function impairment.

Predictors of left ventricular remodeling after ST-elevation myocardial infarction

Adverse left ventricular (LV) remodeling after acute ST-elevation myocardial infarction (STEMI) is associated with morbidity and mortality. We studied clinical, biochemical and angiographic determinants of LV end diastolic volume index (LVEDVi), end systolic volume index (LVESVi) and mass index (LVMi) as global LV remodeling parameters 4 months after STEMI, as well as end diastolic wall thickness (EDWT) and end systolic wall thickness (ESWT) of the non-infarcted myocardium, as compensatory remote LV remodeling parameters. Data was collected in 271 patients participating in the GIPS-III trial, presenting with a first STEMI. Laboratory measures were collected at baseline, 2 weeks, and 6–8 weeks. Cardiovascular magnetic resonance imaging (CMR) was performed 4 months after STEMI. Linear regression analyses were performed to determine predictors. At baseline, patients were 21% female, median age was 58 years. At 4 months, mean LV ejection fraction (LVEF) was 54 ± 9%, mean infarct size was 9.0 ± 7.9% of LVM. Strongest univariate predictors (all p < 0.001) were peak Troponin T for LVEDVi (R2 = 0.26), peak CK-MB for LVESVi (R2 = 0.41), NT-proBNP at 2 weeks for LVMi (R2 = 0.24), body surface area for EDWT (R2 = 0.32), and weight for ESWT (R2 = 0.29). After multivariable analysis, cardiac biomarkers remained the strongest predictors of LVMi, LVEDVi and LVESVi. NT-proBNP but none of the acute cardiac injury biomarkers were associated with remote LV wall thickness. Our analyses illustrate the value of cardiac specific biochemical biomarkers in predicting global LV remodeling after STEMI. We found no evidence for a hypertrophic response of the non-infarcted myocardium.

Mild and Short-Term Caloric Restriction Prevents Obesity-Induced Cardiomyopathy in Young Zucker Rats without Changing in Metabolites and Fatty Acids Cardiac Profile.

Caloric restriction (CR) ameliorates cardiac dysfunction associated with obesity. However, most of the studies have been performed under severe CR (30–65% caloric intake decrease) for several months or even years in aged animals. Here, we investigated whether mild (20% food intake reduction) and short-term (2-weeks) CR prevented the obese cardiomyopathy phenotype and improved the metabolic profile of young (14 weeks of age) genetically obese Zucker fa/fa rats. Heart weight (HW) and HW/tibia length ratio was significantly lower in fa/fa rats after 2 weeks of CR than in counterparts fed ad libitum. Invasive pressure measurements showed that systolic blood pressure, maximal rate of positive left ventricle (LV) pressure, LV systolic pressure and LV end-diastolic pressure were all significantly higher in obese fa/fa rats than in lean counterparts, which were prevented by CR. Magnetic resonance imaging revealed that the increase in LV end-systolic volume, stroke volume and LV wall thickness observed in fa/fa rats was significantly lower in animals on CR diet. Histological analysis also revealed that CR blocked the significant increase in cardiomyocyte diameter in obese fa/fa rats. High resolution magic angle spinning magnetic resonance spectroscopy analysis of the LV revealed a global decrease in metabolites such as taurine, creatine and phosphocreatine, glutamate, glutamine and glutathione, in obese fa/fa rats, whereas lactate concentration was increased. By contrast, fatty acid concentrations in LV tissue were significantly elevated in obese fa/fa rats. CR failed to restore the LV metabolomic profile of obese fa/fa rats. In conclusion, mild and short-term CR prevented an obesity-induced cardiomyopathy phenotype in young obese fa/fa rats independently of the cardiac metabolic profile.

Left Ventricle Segmentation Using a Combination of Region Growing and Graph Based Method

Background: Left ventricle segmentation plays an essential role in computation of cardiac functional parameters such as ventricular end diastolic and end systolic volumes, ejection fraction, myocardial mass, and wall thickness and also wall motion analysis. Manual segmentation is also time consuming and suffers from inter and intra observer variability. Several approaches have been proposed that segment the left ventricle (LV) by automatic and semi-automatic methods, but the problem is still open due to the huge shape variety of the left ventricle and motion artifact. Materials and Methods: A robust semi-automatic approach is hereby presented for addressing the left ventricle segmentation problem. The presented method combines region information of the left ventricle with gradient and edge information in a graph framework. The LV region information is captured using our previously presented region growing method and is embedded into livewire framework. Results: The modified livewire that is presented here shows a great success in quantitative criteria over the publically available MICCAI 2009 left ventricle segmentation challenge database that contains 45 normal and abnormal cases. We have computed dice metric (DM) and average perpendicular distance (APD) for the proposed method and it outperformed the state of the art results over all papers that used the same database. Validation metrics, dice metric and average perpendicular distance were computed as 0.95 mm and 1.48 mm versus those of 0.87 - 0.93 mm and 1.76 - 1.81 mm obtained by other methods, respectively. Conclusion: Using semi-automatic approaches for cardiac segmentation yields satisfying results and this is because of incorporating radiologist’s experiences into the segmentation procedure. Maintaining image information to reduce user interaction is our goal for further researches.