Left Ventricular Cardiac Function Research Articles

Long-term consumption of artificial sweeteners does not affect cardiovascular health and survival in rats.

BackgroundRecent epidemiological cohort studies have suggested that consumption of artificial sweeteners (AS) is associated with adverse cardiovascular events and mortality. However, these population association studies cannot establish a causal relationship. In this study we investigated the effect of long-term (1-year) consumption of AS (Equal and Splenda, two commonly used AS) on cardiovascular health and survival in rats.MethodsAdult Sprague-Dawley rats (both sexes, 4–5 months old) were randomized into the following 3 groups: control (n = 21), AS Equal (n = 21) and Splenda (n = 18). In the AS groups, Equal or Splenda was added to the drinking water (2-packets/250 ml), while drinking water alone was used in the control rats. The treatment was administered for 12 months. Cardiovascular function and survival were monitored in all animals.ResultsIt was found that rats in the AS groups consistently consumed more sweetened water than those in the control group. AS did not affect body weight, non-fasting blood cholesterol, triglycerides, blood pressure or pulse wave velocity. There were no significant differences in left ventricular wall thicknesses, chamber dimension, cardiac function or survival. AS did not affect heart rate or atrial effective refractory period. However, rats in both Equal and Splenda groups had prolonged PR intervals (63 ± 5ms in Equal, 68 ± 6 ms in Splenda, vs 56 ± 8 ms in control, p < 0.05) and a tendency of increased atrial fibrillation inducibility.ConclusionLong-term consumption of AS does not affect cardiovascular structure, function or survival but may cause some electrophysiological abnormalities with prolonged PR intervals and a tendency of increased atrial fibrillation inducibility in rats.

Protective effect of a chronic hypobaric hypoxic environment at high altitude on cardiotoxicity induced by doxorubicin in rats: a 7 T magnetic resonance study.

Doxorubicin (DOX)-induced cardiotoxicity (DIC), a major clinical problem, has no effective preventive therapies. We hypothesized that left ventricular (LV) systolic function would be improved in a chronic hypobaric hypoxia environment at high altitude. The purpose of this study was to investigate whether cardiovascular magnetic resonance could reveal the cardioprotective effect of chronic hypobaric hypoxia on DIC. In total, 60 rats were randomly assigned to 1 of 6 groups (n=10 per group): the P group (plain), PD group (plain + DOX), HH group (high altitude), HHD4 group (high altitude + DOX for 4 weeks), HHD8 group (high altitude + DOX for 8 weeks), and HHD12 group (high altitude + DOX for 12 weeks). The rats were transported to either Yushu (altitude: 4,250 m) or Chengdu (altitude: 500 m) where they underwent intraperitoneal injection of DOX (5 mg/kg/week for 3 weeks) or saline. Preclinical 7 T cardiovascular magnetic resonance was performed at weeks 4, 8, and 12. Tissue tracking was used to measure LV cardiac function and to analyze global and segmental strains. Subsequently, histological and oxidative stress tests were performed to evaluate the protective effect of a high-altitude environment on DIC. The left ventricular ejection fraction (LVEF) and global and regional strains in the middle, apical, anterior, septal, inferior, and lateral segments (all P<0.05) were improved in the HHD4 group compared with the PD group. The global strain was significantly greater in absolute value in the HHD8 and HHD12 groups than in the HHD4 group (all P<0.05). Additionally, histological and enzyme-linked immunosorbent assay evaluations supported the in vivo results. A chronic hypobaric and hypoxic environment at high altitude partially prevented cardiac dysfunction and increased global and regional strain in DIC rat models, thereby minimizing myocardial injury and fibrosis. In addition, by increasing the total duration of chronic hypobaric hypoxia, the global strain was further increased, which was likely due to reduced oxidative stress.

Meta-Analysis of Catheter Ablation versus Medical Therapy for Heart Failure Complicated with Atrial Fibrillation.

Objective To compare the efficacy of catheter ablation and medical therapy in patients with heart failure and atrial fibrillation. Methods We searched randomized controlled trials comparing catheter ablation versus medical therapy for heart failure and atrial fibrillation through PubMed, MEDLINE, Embase, Cochrane Clinical Trials Database, Web of Science, and China National Knowledge Infrastructure. Articles were investigated for their methodological quality using the Cochrane Collaboration risk of the bias assessment tool. Forest plots, funnel plots, and sensitivity analysis were also performed on the included articles. Results were expressed as risk ratio (RR) and mean difference (MD) with 95% confidence intervals. Results Nine (9) studies were included in this study with 1131 patients. Meta-analysis showed a reduction in all-cause mortality from catheter ablation compared with medical therapy (RR = 0.53, 95% CI = 0.37 to 0.76; P=0.0007) and improved left ventricular ejection fraction (LVEF) (MD = 6.45, 95% CI = 3.49 to 9.41; P < 0.0001), 6-minute walking time (6MWT) (MD = 28.32, 95% CI = 17.77 to 38.87; P < 0.0001), and Minnesota Living with Heart Failure Questionnaire (MLHFQ) score (MD = 8.19, 95% CI = 0.30 to 16.08; P=0.04). Conclusion Catheter ablation had a better improvement than medical treatment in left ventricular ejection fraction, cardiac function, and exercise ability for atrial fibrillation and heart failure patients.

Effect of L-carnitine on left ventricular remodeling and cardiac function after PCI in patients with acute myocardial infarction.

article: Effect of L-carnitine on left ventricular remodeling and cardiac function after PCI in patients with acute myocardial infarction - Minerva Surgery 2022 August;77(4):403-6 - Minerva Medica - Journals

Cardiovascular outcomes after simultaneous pancreas kidney transplantation compared to kidney transplantation alone: a propensity score matching analysis

BackgroundCoronary heart disease due to arteriosclerosis is the leading cause of death in type 1 diabetic patients with end-stage renal disease (ESRD). The aim of this study was to evaluate the effect of simultaneous pancreas kidney transplantation (SPKT) compared to kidney transplantation alone (KTA) on survival, cardiovascular function and metabolic outcomes.MethodsA cohort of 127 insulin-dependent diabetes mellitus (IDDM) patients with ESRD who underwent either SPKT (n = 100) or KTA (n = 27) between 1998 and 2019 at the University Hospital of Leipzig were retrospectively evaluated with regard to cardiovascular and metabolic function/outcomes as well as survival rates. An additional focus was placed on the echocardiographic assessment of systolic and diastolic cardiac function pretransplant and during follow-up. To avoid selection bias, a 2:1 propensity score matching analysis (PSM) was performed.ResultsAfter PSM, a total of 63 patients were identified; 42 patients underwent SPKT, and 21 patients received KTA. Compared with the KTA group, SPKT recipients received organs from younger donors (p < 0.05) and donor BMI was higher (p = 0.09). The risk factor-adjusted hazard ratio for mortality in SPKT recipients compared to KTA recipients was 0.63 (CI: 0.49–0.89; P < 0.05). The incidence of pretransplant cardiovascular events was higher in the KTA group (KTA: n = 10, 47% versus SPKT: n = 10, 23%; p = 0.06), but this difference was not significant. However, the occurrence of cardiovascular events in the SPKT group (n = 3, 7%) was significantly diminished after transplantation compared to that in the KTA recipients (n = 6, 28%; p = 0.02). The cardiovascular death rate was higher in KTA recipients (19%) than in SPK recipients with functioning grafts (3.3%) and comparable to that in patients with failed SPKT (16.7%) (p = 0.16).In line with pretransplant values, SPKT recipients showed significant improvements in Hb1ac values (p = 0.001), blood pressure control (p = < 0.005) and low-density lipoprotein/high-density lipoprotein (LDL/HDL) ratio (p = < 0.005) 5 years after transplantation. With regard to echocardiographic assessment, SPKT recipients showed significant improvements in left ventricular systolic parameters during follow-up.ConclusionsNormoglycaemia and improvement of lipid metabolism and blood pressure control achieved by successful SPKT are associated with beneficial effects on survival, cardiovascular outcomes and systolic left ventricular cardiac function. Future studies with larger samples are needed to make predictions regarding cardiovascular events and graft survival.

107 Real-Time Computer Vision TTE Analytics using Existing Ultrasound Workflows

Real time ‘AI’ applications utilizing point-of-care ultrasound are often commercialized, expensive and do not work with existing ultrasound machines and workflows, hampering the reach of effective computer vision techniques to assist at the bedside for diagnostic and teaching purposes. The purpose of this study is to evaluate whether formal transthoracic echocardiogram studies can be used for transfer learning on ED echocardiogram views and to build a portable model for real-time cardiac function categorization at the bedside that works with existing ultrasound equipment. The ultimate goal of the project is to create a portable hardware and software solution that works with existing ED ultrasound machines and workflows. A previously described three-dimensional convolutional neural network (CNN), trained on 10, 030 formal transthoracic echocardiogram apical 4-chamber (A4C), was adapted for use in the ED. Expert sonographer tracings were used through weak supervision to generate frame-level semantic segmentations of the left ventricle to output video of cardiac function over time. 1123 ED A4C videos from July 2020 to December 2020 were intermixed by labeling them into four categories (‘normal,’ ‘slightly reduced,’ ‘moderately reduced,’ ‘severely reduced’) by board certified emergency physicians and consensus labeling was done by an ultrasound division faculty member. Given variability of ED A4C videos and to assist with CNN training, an interpretability label (‘yes,’ ‘partial,’ ‘no’) was also obtained corresponding to all, some, and none of the beats complete and clinically interpretable. These labeled videos were intermixed with the formal echocardiogram video set and the CNN was retrained to provide binary output (normal vs hypo- contractile) and segmented video of left ventricular cardiac function over time. Receiver operating characteristic curves (ROC) were generated to assess diagnostic ability. Finally, the video output port of an ultrasound machine was used to generate model outputs (label and segmented video) available to providers in near real-time (<0.2 seconds to create model output) using inexpensive hardware at the bedside. An initial set of 133 A4C videos were evaluated by the model before any retraining was done with a ROC of 0.81 (95% CI: 0.77 - 0.85) for a binary classifier. After intermixing the remaining ED videos and retraining the CNN, an improved ROC of 0.91 (95% CI: 0.89 - 0.94) was observed for a binary classifier. For test set A4C videos that the model deemed interpretable, segmented videos accurately demonstrated contractility by shading left ventricular cardiac function. A three-dimensional CNN trained on a cardiology echocardiogram dataset can be retrained using ED A4C videos to provide high discriminatory value and be adapted for existing ED ultrasound machines and workflows providing an inexpensive tool for real-time feedback at the bedside. Along with categorical labeling, segmented video output can help with uptake of and understanding model output, potentially lowering the barrier to entry to ED echocardiography for providers lacking formal ultrasound training and providing guidance to trainees.

Abstract P500: Naltrindole And Naltrindole Derivatives Exhibit Potent Cardioprotection In Myocardial Ischemia Reperfusion Injury

Previously, naltrindole (NTI; selective delta opioid receptor antagonist) was shown to improve post-reperfused cardiac function and reduced infarct size when given prior to ischemia (I)/ reperfusion (R) in ex-vivo rat hearts. Conversely, naloxone (NX, broad-spectrum opioid antagonist) and nor-binaltrophine (BNI, selective kappa receptor antagonist) were similar to control hearts. In this study, the effects of NTI derivatives naltriben (NTB, delta receptor antagonist) and guanidonaltrindole (GNTI, kappa receptor antagonist) were compared to NTI, BNI, and NX. Isolated hearts from male SD rats (300g) were subjected to global I(30min)/R(45min). Treatments were given 5 min before I (preconditioning) and during the first 5 min of R. Left ventricular (LV) cardiac function was measured using a pressure transducer. At the end of reperfusion, infarcted heart tissue was compared to total tissue weight. Data were evaluated using ANOVA. As shown in Table 1, NTI, NTB, and GNTI significantly improved post-reperfused cardiac function and reduced infarct size compared to control hearts. NTI and NTB elicited direct effects on cardiac function when given during preconditioning in contrast to all other study groups and were the most robust at reducing infarct size and restoring post reperfusion cardiac function. The negative inotropic effects of NTI and NTB were correlated with a decrease in the rise of ischemic pressure. GNTI also elicited significant improvement in post-reperfused cardiac function and reduction of infarct size compared to BNI which suggests a separate cardioprotective mechanism that this NTI derivative may exert in contrast to kappa opioid receptor inhibition. Results suggest that NTI and derivatives, GNTI and NTB, are cardioprotective against I/R injury resulting in reduced ischemic peak pressure (NTI/NTB) and infarct size. In future studies, we will examine the mechanism of the protective effects of NTI and derivatives in hearts subjected to I/R injury.

Estrogen normalizes maternal HFD-induced cardiac hypertrophy in offspring by regulating AT2R.

Our previous study has demonstrated maternal high-fat diet (HFD) caused sex-dependent cardiac hypertrophy in adult male, but not female offspring. The present study tested the hypothesis that estrogen normalizes maternal HFD-induced cardiac hypertrophy by regulating angiotensin II receptor (ATR) expression in adult female offspring. Pregnant rats were divided into the normal diet (ND) and HFD (60% kcal fat) groups. Ovariectomy (OVX) and 17β-estradiol (E2) replacement were performed on 8-week-old female offspring. Maternal HFD had no effect on left ventricular (LV) wall thickness, cardiac function and molecular markers of cardiac hypertrophy function in sham groups. However, maternal HFD caused cardiac hypertrophy of offspring in OVX groups, which was abrogated by E2 replacement. In addition, maternal HFD had no effect on ERα and ERβ in sham groups. In contrast, HFD significantly decreased ERα, but not ERβ in OVX groups. In sham groups, there was no difference in the cardiac ATR type 1 (AT1R) and ATR type 2 (AT2R) between ND and HFD offspring. HFD significantly increased AT2R, but not AT1R in OVX groups. Furthermore, maternal HFD resulted in decreased glucocorticoid receptors (GRs) binding to the glucocorticoid response elements at the AT2R promoter, which was due to decreased GRs in hearts from OVX offspring. These HFD-induced changes in OVX groups were abrogated by E2 replacement. These results support a key role of estrogen in the sex difference of maternal HFD-induced cardiac hypertrophy in offspring, and suggest that estrogen protects female offspring from cardiac hypertrophy in adulthood by regulating AT2R.

Long‐term Consumption of Artificial Sweeteners Does not Affect Cardiovascular Function but May Cause Cardiac Electrophysiological Abnormalities in Rats

Introduction Artificial sweeteners are commonly used as sugar substitutes. Because they have virtually no calories, they are believed to be useful in combatting obesity, metabolic syndrome, and diabetes. However, there is still uncertainty about their potential health problems. Recent population studies have suggested that consumption of artificial sweeteners was associated with adverse cardiovascular events - in particular, increasing coronary artery disease, stroke and all-cause mortality. Nevertheless, those population association studies cannot establish a causal relationship. We hypothesized that long-term consumption of artificial sweeteners could cause cardiovascular dysfunction. Thus, in this study we investigated the effect of long-term (1 year) consumption of artificial sweeteners (Equal and Splenda, 2 commonly used artificial sweeteners) in drinking water on cardiovascular health in rats. Methods Adult Sprague-Dawley rats (both sexes, 4-5 months old) were randomized into the following 3 groups: control group (n=21), artificial sweetener Equal group (n=21) and Splenda group (n=18). In the artificial sweetener groups, Equal or Splenda (at concentration of 2 packs per cup of water) was added to the drinking water, while drinking water alone was used in the control rats. The treatment was administered for 12 months. At the end of the treatment, blood pressure, pulse wave velocity (an index of arterial stiffness), left ventricular pressure and cardiac function were measured using catheter approach and echocardiography. ECG and cardiac electrophysiology was determined using intracardiac catheter approach. Blood glucose and lipids levels were also measured. Results Rats consistently consumed more sweetened water in both Equal and Splenda groups than that in the control group (e.g., 45±6ml in control, 72±5ml in Equal and 74±14ml in Splenda groups at 2 week treatment, P<0.01). The body weight was comparable among the 3 groups. The blood pressure and pulse wave velocity were not altered after 1-year treatment. There were no significant differences in left ventricular wall thicknesses, chamber dimension and cardiac function evaluated with cardiac echocardiography and left ventricular hemodynamic at the end of the experiment. There were no differences in blood lipids and glucose levels. Artificial sweeteners did not affect heart rate and atrial effective refractory period. However, rats in both Equal and Splenda groups had longer PR intervals (63±5ms in Equal, 68±6 ms in Splenda, vs 56±8ms in control, p<0.01) and a tendency of increased atrial fibrillation inducibility (60% in Equal, 70% in Splenda vs 31% in control). The survival (15/21 in Equal, 10/18 in Splenda, and 16/21 in control) was not significantly affected by the 1-year treatment. Conclusions Long-term consumption of artificial sweeteners in drinking water did not affect blood glucose and lipids levels. The artificial sweeteners did not affect blood pressure and cardiovascular function but caused some electrophysiological abnormalities with prolonged PR interval and a tendency of increased atrial fibrillation inducibility in rats. The 1-year survival was not significantly affected in these animals.

Naltrindole Exhibits Robust Cardioprotection in Myocardial Ischemia Reperfusion Injury

The predominant opioid receptor subtypes in heart tissue are delta and kappa opioid receptors. Activation of delta and kappa opioid receptors during preconditioning have been shown to reduce infarct size in myocardial ischemia reperfusion (I/R) injury. This cardioprotective effect has been abolished with naloxone (NX), a broad-spectrum opioid receptor antagonist (e.g., delta, kappa, and mu). Previously, we demonstrated that a novel tripeptide, structurally similar to other delta or kappa opioid peptide receptor agonists, when given prior to global ischemia, significantly reduced infarct size and improved post-reperfused cardiac function using a Langendorf rat I/R heart ex vivo model. To identify the opioid receptor subtype responsible for tripeptide's cardioprotective effects, we used naltrindole (NTI), a selective delta opioid receptor antagonist. The cardioprotective effects of tripeptide were blocked by NX, but not NTI. To determine whether the cardioprotective effects of the combination was due to tripeptide or NTI, the effects of NTI and NX were evaluated individually in the same model. Male Sprague-Dawley rats (~300g) were subjected to global I(30min)/R(50min). NX (10 μM, n=6) or NTI (5 μM, n=8) or H2O vehicle (control n= 10) were given to hearts 5 min prior to ischemia and during the first 5 min of reperfusion in a Langendorf perfused model. Left ventricular (LV) cardiac function indices were measured using a pressure transducer. At the end of reperfusion (50min), hearts were frozen, sectioned (2 mm), and stained with 1% triphenyltetrazolium chloride (TTC). Infarcted heart tissue was compared to total tissue weight. Data were evaluated using ANOVA Student-Newman-Keuls post-hoc analysis. Control hearts (n=10) exhibited increased final LV end diastolic pressure (LVEDP) of 60±5 mmHg from baseline values (~8mmHg for all groups) and a mean infarct size of 36 ± 3% at 50 min post-reperfusion. NX showed no significant cardioprotective effect, since final LVEDP (64 ± 5%) and infarct size (35 ± 5%) was similar to control hearts. Surprisingly, the selective delta opioid antagonist, NTI, remarkably improved final LVEDP to 17 ± 3mmHg to near baseline values and reduced infarct size to 7 ± 2% compared to control and NX hearts (both p<0.01). The results indicate that NTI can prevent ischemic injury and restore post-reperfused heart function to pre-ischemic levels. In future studies, we will examine the intracellular mechanisms of NTI responsible for preventing myocardial ischemic injury.

Possible diverse contribution of coronary risk factors to left ventricular systolic and diastolic cavity sizes

It is generally believed that risk factors damage the coronary arteries, cause myocardial ischemia, and consequently change the shape of the heart. On the other hand, each of the risk factors may also have a negative effect on the heart. However, it is very difficult to examine the effects of each of these risk factors independently. Therefore, it is necessary to select an appropriate statistical method and apply it efficiently. In this study, the effects of coronary risk factors on left ventricular size and cardiac function were investigated using structure equation modeling (SEM), and were shown as Bayesian SEM-based frequency polygons using selected two-dimensional contours. This study showed that each risk factor directly affected the shape of the heart. Because vascular risk and heart failure risk are likely to evolve at the same time, managing risk factors is very important in reducing the heart failure pandemic.

Correlations of circulating miR-26b level with left ventricular hypertrophy and cardiac function in elderly patients with hypertension.

Objectives:To study the correlations of circulating miR-26b level with left ventricular hypertrophy (LVH) and cardiac function in elderly patients with hypertension.Methods:A total of 132 eligible patients were divided into low and high miR-26b level groups. Their baseline clinical data and biochemical indices were compared. The correlations between miR-26b level and echocardiographic parameters were studied by Pearson’s analysis. Factors affecting LVH were explored by multivariate logistic regression analysis. The role of miR-26b in diagnosing LVH was predicted by receiver operating characteristic curve.Results:The relative expression level of miR-26b was 4.56-16.93, with a median of 7.62. The two groups had similar baseline clinical data and biochemical indices (P>0.05). Compared with high miR-26b level group, interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), left ventricular mass index (LVMI) and number of LVH cases in low miR-26b level group significantly increased (P<0.05), and mitral ratio of peak early to late diastolic filling velocity (E/A) decreased (P<0.05). Circulating miR-26b level was negatively correlated with IVST, LVPWT and LVMI (P<0.0001), and positively correlated with E/A (P<0.0001). The proportion of cardiac hypofunction cases in low miR-26b level group significantly exceeded that of high miR-26b level group (P<0.05). Age and increased IVST, LVPWT and LVMI were independent risk factors for LVH (P<0.05), and elevated miR-26b level was a protective factor (P<0.05). AUC was 0.836, and the optimal cutoff value was 8.83, with high sensitivity and specificity.Conclusions:MiR-26b level is negatively correlated with LVH and positively correlated with left ventricular diastolic function in elderly hypertensive patients. It is a protective factor for LVH complicated with diastolic dysfunction and a potential biomarker for diagnosis.

Water-soluble lectin (WSMoL) from Moringa oleifera seeds treatment recovers glycemic levels and improves left ventricular ejection fraction on Type-2 Diabetes mice model.

Moringa oleifera, a plant widely used in traditional medicine as well as for water purification, contains a lectin on its seeds named WSMoL which modulates several immune characteristics and has shown cardiac safe properties. Here, we tested the hypothesis that WSMoL is able to recover fasting glucose levels and to improve the cardiac left ventricular (LV) function in a type 2 diabetes mellitus (T2DM) mice model. T2DM was induced in adult C57BL/6 mice by combining a high fat diet and low doses of Streptozotocin. Mice were randomly divided in two groups: i. received WSMoL for 21 consecutive days by gavage (T2DM + WSMoL) and ii. received saline solution (T2DM). Metabolic parameters and LV function were assessed. WSMoL was able to reduce fasting blood glucose levels in T2DM mice after 2 weeks of treatment, when compared to T2DM untreated group. Regarding to cardiac LV function, the T2DM + WSMoL group depicted ejection fraction values comparable to non-diabetic group. Our results show: i. WSMoL treatment presented a potent hypoglycemic effect decreasing insulin resistance and ii. WSMoL was able to improve cardiac LV ejection fraction. Collectively, the results presented here show WSMoL as a potential hypoglycemic agent to be tested in T2DM patients.

Quercetin Reverses Cardiac Systolic Dysfunction in Mice Fed with a High-Fat Diet: Role of Angiogenesis.

Global consumption of high-fat diets (HFD) is associated with an increased incidence of cardiometabolic syndrome and cardiac injury, warranting identification of cardioprotective strategies. Cardioprotective effects of quercetin (Q) have mostly been evaluated in ischemic heart disease models and attributed to senolysis. We hypothesized that Q could alleviate murine cardiac damage caused by HFD by restoring the myocardial microcirculation. C57BL/6J mice were fed standard chow or HFD for 6 months and then treated with Q (50 mg/kg) or vehicle 5-day biweekly for 10 additional weeks. Left ventricular (LV) cardiac function was studied in vivo using magnetic resonance imaging, and intramyocardial fat deposition, microvascular density, oxidative stress, and senescence were analyzed ex vivo. Additionally, direct angiogenic effects of Q were studied in vitro in HUVECs. HFD increased body weight, heart weight, total cholesterol, and triglyceride levels, whereas Q normalized heart weight and triglycerides. LV ejection fraction was lower in HFD vs. control mice (56.20 ± 15.8% vs. 73.38 ± 5.04%, respectively, P < 0.05), but improved in HFD + Q mice (67.42 ± 7.50%, P < 0.05, vs. HFD). Q also prevented cardiac fat accumulation and reduced HFD-induced cardiac fibrosis, cardiomyocyte hypertrophy, oxidative stress, and vascular rarefaction. Cardiac senescence was not observed in any group. In vitro, ox-LDL reduced HUVEC tube formation activity, which Q effectively improved. Quercetin may directly induce angiogenesis and decrease myocardial oxidative stress, which might account for its cardioprotective effects in the murine HFD-fed murine heart independently from senolytic activity. Furthermore, its beneficial effects might be partly attributed to a decrease in plasma triglycerides and intramyocardial fat deposition.

Surgical treatment of congenital left ventricular diverticulum.

BackgroundCongenital left ventricular diverticulum (LVD) is a rare cardiac malformation. Its prevalence rate is less than 0.1% of the congenital heart diseases requiring surgery. Some scholars suggest that all LVD should be actively removed to prevent possible risks, including diverticulum rupture, arterial embolism, and malignant arrhythmia. However, others believe that asymptomatic LVD can be followed up without immediate surgery. We reviewed and reported the diagnosis, clinical features, and surgical treatment of four cases of congenital LVD to provide clinical experience and a reference for the treatment of such patients.MethodsFour patients (aged 3–32 years old) were diagnosed with congenital LVD and received surgical treatment at the Department of Cardiovascular Surgery of PLA General Hospital, Beijing, China from September 2009 to July 2019. All four patients had complete long-term postoperative follow-up data, including echocardiogram, enhanced cardiac computed tomography (CT), and electrocardiogram to monitor changes in left ventricular structure, heart function, and heart rhythm.ResultsIn the first case, the fibrodiverticulum under the aortic valve squeezed the right ventricular outflow tract and the right main coronary artery; the morphology of the right ventricle and coronary artery returned to normal after surgery. The second patient was complicated with a huge lipoma in the apex of the left ventricle and underwent lipoma resection during LVD resection surgery. The third and fourth cases had muscular diverticula in the left ventricular apexes and received LVD removal surgery. All four patients recovered well after surgery and their left ventricular morphology and cardiac function were normal without adverse complications, such as atrial fibrillation, ventricular arrhythmia, and cerebrovascular accident.ConclusionsAlthough the morphology and character of congenital LVD were different in each case, the use of effective diagnostic and follow-up tools, including echocardiogram, enhanced CT, and magnetic resonance imaging (MRI), allowed for successful surgical treatment of the left ventricular diverticula and symptoms or other malformations. We propose that congenital LVD should be actively treated with surgery, especially considering effectiveness and low risk associated with this therapeutic option.

Turkish reference ranges for the left fetal modified myocardial performance index.

This study aimed to assess fetal cardiac left ventricular function in healthy pregnant women by calculating the modified myocardial performance index (Mod-MPI) and to construct reference ranges for the Turkish population. One-hundred-two randomly selected healthy singleton pregnant women ranging between 25 and 39 gestational weeks were included in the study. Left fetal Mod-MPI was measured for each pregnant woman. Women with chronic systemic diseases or fetuses with chromosomal or structural abnormalities were excluded from the study. Mitral valve (MV) and aortic valve (AoV) clicks were used as landmarks to define the following time periods that were used to calculate the Mod-MPI: isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), and ejection time (ET). The mean Mod-MPI was 0.42±0.10. The mean IRT, ICT, and ET were 43.5±10.2, 27.27±8.1, and 170.5±16.9, respectively. A significant correlation was found between Mod-MPI and gestational age, umbilical artery systolic/diastolic (UA S/D) ratio and the middle cerebral artery pulsatility index (MCA PI) values (r=0.199, p=0.047, r=-0.328, p=0.001, and r=-0.0349, p=0.001, respectively) Conclusions. The current study`s results will be a reference for future studies, especially studies investigating pathological conditions that impact fetal cardiac function.

Exercise-Induced Cardiac Fatigue after a 45-Minute Bout of High-Intensity Running Exercise Is Not Altered under Hypoxia

Acute exercise promotes transient exercise-induced cardiac fatigue, which affects the right ventricle and to a lesser extent the left ventricle. Hypoxic exposure induces an additional increase in right ventricular (RV) afterload. Therefore, exercise in hypoxia may differently affect both ventricles. The aim of this study was to investigate the acute effects of a bout of high-intensity exercise under hypoxia versus normoxia in healthy individuals on right- and left-sided cardiac function and mechanics. Twenty-one healthy individuals (mean age, 22.2±0.6years; 14 men) performed 45-min high-intensity running exercise under hypoxia (fraction of inspired oxygen 14.5%) and normoxia (fraction of inspired oxygen 20.9%) in a randomized order. Pre- and post-exercise echocardiography, at rest and during low-to-moderate intensity recumbent exercise ("stress"), was performed to assess RV and left ventricular (LV) cardiac function and mechanics. RV structure, function, and mechanics were assessed using conventional two-dimensional, Doppler, tissue Doppler, speckle-tracking echocardiographic, and novel strain-area loops. Indices of RV systolic function (RV fractional area change, Tricuspid annular plane systolic excursion, RV s', and RV free wall strain) and LV function (LV ejection fraction and LV global longitudinal strain) were significantly reduced after high-intensity running exercise (P<.01). These exercise-induced changes were more pronounced when echocardiography was examined during stress compared with baseline. These responses in RV and LV indices were not altered under hypoxia (P>.05). There was no impact of hypoxia on the magnitude of exercise-induced cardiac fatigue in the right and left ventricles after a 45-min bout of high-intensity exercise. This finding suggests that any potential increase in loading conditions does not automatically exacerbate exercise-induced cardiac fatigue in this setting.

Infarct characteristics and outcome of patients with transient ST-segment elevation myocardial infarction compared to ST-segment and non-ST-segment elevation myocardial infarction

Abstract Background Up to one out of four patients with signs of ST-segment elevation myocardial infarction (STEMI) express complete normalization of ST elevation before primary revascularization procedure. This condition is commonly referred to as “transient ST-segment elevation myocardial infarction” (TSTEMI) and recent data suggests that this group of patients may have favorable outcome compared to STEMI patients. However, it is currently unknown how these patients compare to both STEMI and non-ST-segment elevation myocardial infarction (NSTEMI) patients with respect to infarct size characteristics and outcome. Objective This study aims to explore cardiac magnetic resonance (CMR) derived scar tissue and 1-year outcome in patients with TSTEMI by comparison to STEMI and NSTEMI. Methods Patients with STEMI were enrolled from two prospective studies (n=170); the patients with TSTEMI were recruited from the TRANSIENT trial (n=141); the patients with NSTEMI were prospectively and consecutively collected from local registries of Amsterdam UMC (n=57) and Maastricht UMC (n=51). All patients underwent CMR examination 2–8 days after the index event. Cine imaging was done for volume and function assessment. Late gadolinium enhancement imaging was performed to identify infarct size (in grams) and the presence of microvascular obstruction (MVO). All CMR images were processed in a single core laboratory (Amsterdam UMC). Clinical outcome after 1 year was measured by the incidence of major adverse cardiac events (MACE), defined as recurrent myocardial infarction (MI), revascularization and all cause death. Results The TSTEMI group demonstrated the lowest end-systolic left ventricular volume and highest left ventricular ejection fraction across the groups (overall p&amp;lt;0.001). Although there was a remarkably lower infarct size in TSTEMI patients compared to STEMI (1.41g [0.00–3.91] vs 13.48g [5.31–26.81], p&amp;lt;0.001), there was only a trend towards lower infarct size compared to NSTEMI patients (1.41g [0.00–3.91] vs 2.13g [0.00–8.64], p=0.06). Whilst MVO was observed less frequently in TSTEMI compared to STEMI patients (5 (4%) vs 53 (31%), p&amp;lt;0.001), no significant difference was seen between TSTEMI and NSTEMI patients (5 (4%) vs 5 (5%), p=0.72). Multivariable linear regression analysis identified infarct type, smoking, peak troponin-T and pre-PCI TIMI flow as predictors for infarct size (p=0.03, p=0.03, p&amp;lt;0.001 and p&amp;lt;0.001, respectively). One-year mortality rate was low in all 3 MI types (TSTEMI 3 (2.2%), NSTEMI 3 (3.1%), 4 (2.4%), log-rank test p=0.91). However, there was a significant difference in MACE at 1 year across the 3 MI types (TSTEMI 18 (13.2%), NSTEMI 19 (19.4%), STEMI 11 (6.7%), overall p&amp;lt;0.01). Conclusion In comparison to NSTEMI and STEMI, TSTEMI yielded favorable cardiac left ventricular function and scar mass. However, this did not lead to benefit in short term (1-year) outcome; further studies are needed with longer follow-up. Funding Acknowledgement Type of funding source: Other. Main funding source(s): European Association of Cardiovascular Imaging (EACVI) Research Grant

Effect of long term CPAP therapy on cardiac parameters assessed with cardiac MRI

The obstructive sleep apnoea syndrome (OSAS) is a disorder with a high prevalence and is associated with an elevated cardiovascular risk and increased morbidity and mortality. For longitudinal studies and functional analysis cardiac MRI is regarded as the gold standard. Aim of this study was to evaluate the long-term effect of continuous positive airway pressure (CPAP) therapy on cardiac functional parameters with cardiac Magnetic Resonance Imaging (cMRI). 54 patients with OSAS (mean apnea hypopnea index-AHI: 31) were prospectively enrolled in this study and cMRI was performed before and after 7 months of CPAP therapy. Data were acquired on a 1.5 T MRI and right and left ventricular cardiac function were analysed. CPAP treatment was considered compliant when used ≥ 4 h per night. 24-h blood pressure was measured at baseline and follow up. 33 patients could be assigned to the compliance group. Left ventricular stroke volume (LV SV) and right ventricular ejection fraction (RV EF) improved significantly with CPAP therapy (LV SV from 93 ± 19 to 99 ± 20 ml, p = 0.02; RV EF from 50 ± 6 to 52 ± 6%, p = 0.04). All other cardiac parameters did not change significantly while mean systolic and diastolic blood pressure improved significantly (p < 0.01). 21 patients were assigned to the non-compliance group and were considered as a control group. There were no relevant differences in cardiac parameters between baseline and follow up examination in these patients. CPAP therapy seems to improve LV SV, RV EF, systolic and diastolic blood pressure in OSAS patients, but reproducibility of our results need to be confirmed in a larger patient population.

Cardiac MRI in common marmosets revealing age-dependency of cardiac function

The aim of this study was to establish a feasible and robust magnetic resonance imaging protocol for the quantitative assessment of cardiac function in marmosets and to present normal values of cardiac function across different ages from young adult, middle-aged, to very old clinically healthy animals. Cardiac MRI of 33 anesthetized marmosets at the age of 2–15 years was performed at 9.4 T using IntraGate-FLASH that operates without any ECG-triggering and breath holding. Normalized to post-mortem heart weight, the left ventricular end-diastolic volume (LV-EDV) was significantly reduced in older marmosets. The LV end-systolic volume (LV-ESV) and the LV stroke volume (LV-SV) showed a similar trend while the LV ejection fraction (LV-EF) and wall thickening remained unchanged. Similar observations were made for the right ventricle. Moreover, the total ventricular myocardial volume was lower in older monkeys while no significant difference in heart weight was found. In conclusion, IntraGate-FLASH allowed for quantification of left ventricular cardiac function but seems to underestimate the volumes of the right ventricle. Although less strong and without significant sex differences, the observed age related changes were similar to previously reported findings in humans supporting marmosets as a model system for age related cardiovascular human diseases.