Ventricular End-systolic Volume Research Articles

Right Ventricular Response to Cardiac Resynchronization Therapy: A Three-Dimensional and Speckle Tracking Echocardiographic Study

Cardiac resynchronization therapy (CRT) induces left ventricle reverse remodeling; however, its effects on right ventricular (RV) volumes and function were not well described. This study aimed to assess the effects of CRT on RV. Of 112 patients, 63 enrolled with a mean age of 62.77±7.23years, including 40 males (63.5%). All patients met criteria for CRT implantation and were followed at 3-month and 6-month intervals. Standard 2-dimensional/3-dimensional (3D) echocardiography and speckle-tracking analyses were conducted for assessment of LV and left atrium (LA). RV maximum diameters, tricuspid lateral annular systolic velocity, tricuspid annular plane systolic excursion, fractional area change, RV global (RV 4-chamber strain (RV4CSL), and RV free wall strain (RVFWSL), in addition to 3D echocardiographic assessment of RV, were done before CRT implantation and at follow-up visits. Mean follow-up period was 6.76±1.25months. A total of 48 patients (76.2%) were LV responders (LVR) whereas the rest were nonresponders (LVNR). Both groups had similar baseline characteristics, risk factors, device implantation, and programming values. Only LVR had significant reduction in RV basal diameter, together with significant improvement of RV systolic performance: systolic velocity, fractional area change, RV4CSL, RVFWSL, and 3D-derived RV volumes and ejection fraction, compared with baseline values. In addition, pulmonary arterial systolic pressure decreased in LVR with reduction of tricuspid regurgitation severity. LV response, percentage change of RV4CSL, LA end-systolic volume index, and LA emptying fraction at 3-month follow-up were the most independent predictors of RV response by multivariate analysis. Reduced left ventricular end-systolic volume >13.5% had 92.3% sensitivity and 81.8% specificity. In conclusion, CRT-induced RV reverse remodeling and improved RV-arterial coupling. These effects were associated with left side response to CRT.

The Left ventricular ejection fraction and left ventricular volumes assessed from 99mTC single photon emission tomography technique during stress and rest in relation to age in normal volunteer students.

The heart is subject to structural and functional changes with advancing age. Left ventricular compliance appears to decline with age, which could explain why the elderly have such a high rate of heart failure. Changes in heart function with age are associated with an increased risk of cardiovascular death and morbidity. Various techniques have been used to measure the impact of age on heart structure and function. Subject and methods: The study included 221 healthy adult male and female volunteers (160 females and 61 males, 20–80 years of age). All healthy subjects volunteered to participate in this study. They were classified according to their age. All healthy subjects enrolled in the study underwent myocardial perfusion imaging following the 2-day rest–stress 99mTc sestamibi (GSPECT) protocol. At rest and during stress, end-diastolic volume, end-systolic volume, and ejection fraction using the GSPECT software were assessed both at rest and during stress for comparison. The following parameters were measured: left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), and left ventricular ejection fraction (LVEF). The results show that the change in left ventricular ejection fraction (LVEF) decreased during rest and stress in all age groups. In contrast, the change in left ventricular end-systolic volume (LVESV) increased during stress and rest compared with the left ventricular end-diastolic volume (LVEDV) for all ages. Results show a significant change in EDV, ESV, and EF% (16.49%, 30.35%, -7.49%) with p-value < 0.05 for the groups (20- 49). Also a significant change in EDV, ESV, and EF% (12.13%, 24.86%,-1.62%), respectively, with p-value <0.05. for age range (50-80) years. In conclusion, in people with no cardiac functional or structural problems, the aging process is linked to considerable alterations in left and right ventricular EF, ESV, and EDV. When assessing SPECT with 99mTc investigations, our findings highlight the need to adopt age-adapted data as a reference standard. Keywords: SPECT with 99mTC, Age, Hemodynamics, Rest and Stress

Arrhythmic and mortality outcomes in patients with dilated cardiomyopathy receiving cardiac resynchronization therapy without defibrillator

IntroductionThe routine implantation of cardiac resynchronization therapy with defibrillators in all patients who are candidates for this treatment is now being negotiated, mainly in patients with dilated cardiomyopathy. ObjectiveWe investigated the arrhythmic and mortality outcomes following CRT implantation in DCM, as well as the necessity for defibrillator capabilities in that particular group of patients. Methodswe included 67- patients with DCM with EF ≤ 35%, QRS duration >130 msec and NYHA class II-IV, or those with EF ≤ 35% with indications of permanent pacing for implantation of CRT-P. Patients were followed to obtain good CRT response. Improved clinical outcomes were defined as improvement in at least one NYHA class, ≥5% increase in LVEF, and ≥15% reduction in left ventricular end-systolic volume versus baseline. Patients were classified into responder and non-responder. Patients were followed for 36 months regarding all-cause morbidity mainly ventricular tachycardia and all-cause mortality. ResultsCRT responder patients had better clinical outcomes than CRT non-responder patients (post NYHA, 1.3 ± 0.5 vs. 2.5 ± 0.6, p < 0.0001; post LVEF 30.0 ± 1.6 vs. 20.3 ± 2.2%, p < 0.0001; LVESV, 151.7 ± 7.6 vs. 190.4 ± 9.0 ml, p < 0.0001), with lower ventricular arrhythmia (p < 0.0001), lower mortality (p = 0.015) and lower all-cause morbidity (p < 0.001). This survival advantage may be related to the response to CRT response determined by clinical and echocardiographic parameters over a 36-month period of follow-up. ConclusionsOur findings suggest that CRT-P implantation without defibrillation backup is an encouraging treatment option for patients with DCM, principally those who responded to it. It may result in cost savings, a decrease in complications, and an improvement in all-cause morbidity, particularly ventricular arrhythmia and survival.

Abstract P2161: Stem Cell-derived Exosome Nebulization Therapy (SCENT) Improves Cardiac Function And Tissue Repair In Mice And Pigs

Stem cell-derived exosomes show promise as therapeutics for cardiac repair after injury. However, due to their short half-life in vivo, effective treatment typically requires repeated dosing. Previous methods for delivering exosomes to the heart involve invasive injection routes. Here, we report a noninvasive and repeatable approach to exosome delivery via inhalation after myocardial infarction (MI), called Stem Cell-derived Exosome Nebulization Therapy (SCENT). In a mouse model of MI, exosomes were recruited to the ischemic heart after repeated dosing via nebulization. SCENT ameliorated cardiac repair by significantly improving left ventricular function, reducing infarct size, and promoting cardiomyocyte proliferation. Further investigation via single-cell RNA sequencing of the mouse heart after SCENT revealed a significant downregulation of CD36 in endothelial cells (ECs). In an EC- Cd36 fl/- mouse model, we found that inhibiting CD36, a fatty acid transporter in ECs, led to a compensatory increase in glucose utilization in the heart and higher ATP generation, resulting in enhanced cardiac contractility. In a pig model of acute MI, we evaluated functional outcomes using cardiac magnetic resonance imaging (MRI) and found that SCENT led to reduced left ventricular (LV) end-systolic volume (ESV) at day 28 (19.07 ± 3.22 ml) compared to controls (23.60 ± 3.06 ml). Additionally, pigs treated with SCENT exhibited increased LV ejection fraction (EF) (59.36 ±2.84%) and fractional shortening (FS) (29.56 ± 1.25%), further confirming cardioprotection in pigs. Our results pave the way for development of a non-invasive exosome delivery method for rescuing heart injury.

Abstract P3071: Targeting Neutrophil Sting And Type I Interferon Activation In Myocardial Ischemia-Reperfusion Injury

Introduction: Inflammation following myocardial ischemia/reperfusion (MI/R) plays a significant role in damaging cardiomyocytes and influencing infarct size, with neutrophils being the most rapid and numerous cells in the post-MI/R heart at 24 hours post reperfusion. Preliminary single-cell RNA sequencing data shows type I interferon (IFN) responding neutrophils are present in the hearts of mice 24 hours post-MI/R. The following study aims to address how the type I IFN responding neutrophil phenotype identified in single-cell RNA sequencing data affects cardiac inflammation in MI/R. We hypothesize that STING and type I IFN activation in neutrophils in the early stages of inflammation can exacerbate inflammation, causing further damage to the heart in MI/R. Methods: Male C57BL/6J mice (10-11 weeks old) underwent 60 minutes of ischemia followed by reperfusion, and were dosed with either vehicle, a STING inhibitor (H151), or an IFNAR1 antibody (ab) at reperfusion and at 24 hours following reperfusion. Cardiac function was assessed two weeks post-reperfusion via echocardiography and tissue samples were collected for histological analysis. Results: Mice treated with IFNAR1 ab showed significant improvement in ejection fraction (44.9% ± 6.8) compared to mice treated with vehicle (31.9% ± 6.2; One-way ANOVA, N=5-6, p&lt;0.05). Additionally, mice treated with IFNAR1 ab showed significant improvements in left ventricular end systolic volume (LVESD) (3.16mm ± 0.52) compared to vehicle treated mice (3.89mm ± 0.40; One-way ANOVA, N=5-6, p&lt;0.05). Mice treated with H151 showed significant improvement in ejection fraction (43.8% ± 7.1) compared to mice treated with vehicle (31.9% ± 6.2; One-way ANOVA, N=5-6, p&lt;0.05). Treatment with H151 or IFNAR1 ab reduced scar size (7.22% ± 3.6; 7.88% ± 3.1%) compared to mice treated with vehicle (9.74% ± 3.7; N=5-6). Conclusion: These data show that targeting the early IFN response in MI/R can improve cardiac function, and provide a basis for studies identifying the effects of the neutrophil specific STING and type I IFN activation following MI/R. If correct, this pathway could be a powerful and clinically feasible point of intervention to improve cardiac recovery after MI/R.

The Value of Neutrophil-to-Lymphocyte Ratio and Epicardial Adipose Tissue Thickness in Heart Failure With Preserved Ejection Fraction.

Background Using epicardial adipose tissue thickness (EATt) and neutrophil-to-lymphocyte ratio (NLR) as individual indicators provides beneficial insight into the prognosis of patients suffering from heart failure with preserved ejection fraction (HFpEF). Aim In our study, we aimed to evaluate whether the combined evaluation of NLR and EATt would provide an advantage for identifying high-risk HFpEF patients according to hospitalization for heart failure (HHF) and left ventricular diastolic dysfunction (LVDD). Method A total of 168 outpatients with HFpEF were retrospectively analyzed. The predictive performance of two inflammatory variables was assessed by the receiver operating characteristic curve and a one-way analysis of variance (ANOVA) test. The patients were stratified into three distinct risk categories based on the established cut-off values for EATt and NLR as follows: Group I, high risk; Group II, middle risk; and Group III, low risk. Results Patients in Group I had the highest risk for HHF and the presence of LVDD (p=0.001 for HHF, p=0.011 for LVDD). Patients in Group I also exhibited more symptomatic and a greater number of comorbidities. In Group I, more structural remodeling (enlargedleft ventricular end-systolic volume index (LVESVI) and left atrial volume index (LAVI)) and associated signs of increased intracardiac pressure (elevated E/A ratio, medial E/e') were observed. Conclusion The results of our study indicate that the use of both EATt and NLR among patients with HFpEF may provide better accuracy in predicting HHF and LVDD compared to the use of either EATt or NLR alone.

Cardiac Effects of Long-Duration Space Flight

BackgroundVentricular mass responds to changes in physical activity and loading, with cardiac hypertrophy after exercise training, and cardiac atrophy after sustained inactivity. Ventricular wall stress (ie, loading) decreases during microgravity. Cardiac atrophy does not plateau during 12 weeks of simulated microgravity but is mitigated by concurrent exercise training. ObjectivesThe goal of this study was to determine whether the current exercise countermeasures on the International Space Station (ISS) offset cardiac atrophy during prolonged space flight. MethodsWe measured left ventricular (LV) and right ventricular (RV) mass and volumes (via magnetic resonance imaging) in 13 astronauts (4 females; age 49 ± 4 years), between 75 and 60 days before and 3 days after 155 ± 31 days aboard the ISS. Furthermore, we assessed total cardiac work between 21 and 7 days before space flight and 15 days before the end of the mission. Data were compared via paired-samples t-tests. ResultsTotal cardiac work was lower during space flight (P = 0.008); however, we observed no meaningful difference in LV mass postflight (pre: 115 ± 30 g vs post: 118 ± 29 g; P = 0.053), with marginally higher LV stroke volume (P = 0.074) and ejection fraction postflight (P = 0.075). RV mass (P = 0.999), RV ejection fraction (P = 0.147), and ventricular end-diastolic (P = 0.934) and end-systolic volumes (P = 0.145) were not different postflight. There were strong positive correlations between the relative change in LV mass with the relative changes in total cardiac output (r = 0.73; P = 0.015) and total cardiac work (r = 0.53; P = 0.112). ConclusionsThe current exercise countermeasures used on the ISS appear effective in offsetting reductions in cardiac mass and volume, despite overall reductions in total cardiac work, during prolonged space flight.

Risk factors for mitral valve dysfunction, reoperation and death following repair of the primary mitral valve disease in children.

After primary mitral valve (MV) repair, residual mitral valve regurgitation (MR) and recurred mitral valve stenosis (MS) are the principal occurrences. This study's purpose is to identify the risk factors of MV dysfunction, reoperation and death following repair of primary MV diseases. We retrospectively reviewed 98 patients (47 males and 51 females) with primary MV diseases between January 2013 and December 2021. The median age was 34 months [interquartile range (IQR), 11.4-59] for male and 24 months (IQR, 7.35-72) for female. The left ventricular ejection fraction (LVEF), the left ventricular end-diastolic volume index (LVEDVI) and left ventricular end-systolic volume index (LVESVI) were assessed to evaluate patient's left ventricular function. Risk factors that increased the likelihood of MV dysfunction, reoperation and death after surgery were investigated. During the 23.5 months (IQR, 9-44.5) of follow-up, 5 (5.1%) patients died, including one early death and two late deaths (n=3; 3.9%) in the MR group and one early death and one late death (n=2; 9.1%) in the MS group. Seven (9.2%) patients in the primary MR disease group and 2 (9.1%) patients in the primary MS disease group required a second MV operation for a total reoperation rate of 9.2% (9/98). As of the most recent follow-up, 34 patients experienced MV dysfunction. No significant difference was recorded between primary MR and MS disease groups in Kaplan-Meier freedom from MV dysfunction and reoperation. Mixed MV pathology (P=0.014) acted as an independent risk factor for MV dysfunction, and ≥ moderate MR at 24 h after first surgery (P=0.014) an independent risk factor for MV reoperation. Double-orifice MV technique (P=0.002), MV reoperation (P=0.023) and severe MR at 24 h after first surgery (P=0.028) were independent risk factors for death. The Kaplan-Meier freedom from MV dysfunction and reoperation were comparable between primary MR and MS disease groups. A high probability of MV dysfunction was predicted due to the mixed MV pathology. Patients with ≥ moderate MR at 24 h after first surgery had a higher risk of MV reoperation. Double-orifice MV technique, MV reoperation and severe MR at 24 h after first surgery had a higher risk for death.

Assessment of subclinical left ventricular systolic dysfunction in patients with asymptomatic severe aortic stenosis with preserved left ventricular systolic function by three-dimensional speckle tracking echocardiography.

Left ventricular dysfunction and remodeling can occur as a result of aortic valve stenosis (AS). Three-dimensional speckle tracking echocardiography (3D-STE) can detect early left ventricular myocardial dysfunction even before ejection fraction declines. The purpose of this study was to look at the relationship between various myocardial strain parameters measured by 3D-STE in asymptomatic severe AS patients from Bangladesh. This study included 46 patients with asymptomatic severe AS but preserved LV systolic function (mean age 50.11±12.66 years, LVEF 63.78±3.95%, AS group) and 33 healthy subjects with no cardiovascular disease (mean age 48.21±4.53 years, LVEF 65.15±3.13%, control group). 3D-STE was used to measure left ventricular global myocardial strain parameters such as peak systolic longitudinal strain (PSLS), circumferential strain, radial strain, and area strain. The AS group had significantly thicker interventricular septum and posterior ventricular wall than the control group (1.49±.19cm vs. .81±.09cm, p<.001; 1.73±1.71cm vs. .81±.10cm, p=.003, respectively.) In the AS group, the Indexed Aortic Valve Area (AVA) was significantly lower than in the control group. (.29±.10vs. 2.03±.18, p<.001, respectively). In terms of LVEF (p=.102), left ventricular end diastolic volume (p=.075), or left ventricular end systolic volume (p=.092), no significant inter-group difference was found. However, global PSLS (-10.75±2.27vs. -16.42±2.76, p<.001), circumferential strain (-14.26±3.40vs. -16.64±2.56, p=.001), area strain (-22.70±4.19vs. -26.45±9.90, p=.024) and radial strain (32.20±8.77vs. 41.00±7.52, p<.001) in the AS group were significantly lower than in the control group. Our findings showed reductions in left ventricular global myocardial strains, particularly PSLS in patients suffering from asymptomatic severe AS in Bangladesh; this is consistent with other studies. Reduced area strain, detectable with 3D-STE, is also consistent with that pattern.

Toward the Implementation of Optimal Cardiac Magnetic Resonance Risk Stratification in Pulmonary Arterial Hypertension

The 2022 European Society of Cardiology/European Respiratory Society pulmonary hypertension (PH) guidelines incorporate cardiac magnetic resonance (CMR) imaging metrics in the risk stratification of patients with pulmonary arterial hypertension (PAH). Thresholds to identify patients at estimated 1-year mortality risks of< 5%, 5%to 20%, and > 20%are introduced. However, these cutoff values are mostly single center-based and require external validation. What are the discriminative prognostic properties of the current CMR risk thresholds stratifying patients with PAH? We analyzed data from incident, treatment-naïve patients with PAH from the Amsterdam University Medical Centres, Vrije Universiteit, The Netherlands. The discriminative properties of the proposed CMR three risk strata were tested at baseline and first reassessment, using the following PH guideline variables: right ventricular ejection fraction, indexed right ventricular end-systolic volume, and indexed left ventricular stroke volume. A total of 258 patients with PAH diagnosed between 2001 and 2022 fulfilled the study criteria and were included in this study. Of these, 172 had follow-up CMR imaging after 3months to 1.5 years. According to the CMR three risk strata, most patients were classified at intermediate risk (n= 115 [45%]) upon diagnosis. Only 29(11%) of patients with PAH were classified at low risk, and 114 (44%) were classified at high risk. Poor survival discrimination was seen between risk groups. Appropriate survival discrimination was seen at first reassessment. Risk stratifying patients with PAH with the recent proposed CMR cutoffs from the European Society of Cardiology/European Respiratory Society 2022 PH guidelines requires adjustment because post-processing consensus is lacking and general applicability is limited. Risk assessment at follow-up yielded better survival discrimination, emphasizing the importance of the individual treatment response.

Oligosaccharides and diet-related dilated cardiomyopathy in beagles.

In 2018 the US Food and Drug Administration reported a potential link between grain-free, legume-containing dog foods and the development of canine dilated cardiomyopathy in atypical breeds. One hypothesis was that high oligosaccharide content in legumes reduced bioavailability of taurine, an amino acid with some previous links to canine dilated cardiomyopathy. To address this hypothesis, in the present study, 8 Beagle dogs consumed four diets: a husbandry commercial dental diet, and three test diets formulated with either 30% rice (control), 30% pea (grain-free) or 30% rice with the addition of 1% raffinose (the predominant oligosaccharide found in peas). The study was conducted in a randomized, crossover design with 5 week feeding periods. Measurement of basic health parameters (weight, body condition score, complete blood cell count, chemistry panel), plasma amino acids, cardiac biomarkers (plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac-specific troponin I), fecal bile acids and echocardiographic exams were completed pre-study after feeding the husbandry diet as well as after each test feeding period. Echocardiography showed 9-11% reduction in ejection fraction and 17- 20% greater left ventricular end systolic volume with the husbandry diet compared to both grain-containing test diets. Concentrations of plasma NT-proBNP were 1.3-2 times greater after the husbandry diet compared to the grain-based diet, with the oligosaccharide and pea-based diets showing intermediate levels. Plasma taurine levels were unchanged across diets, while plasma methionine levels were highest and cysteine/cystine levels were lowest after dogs ate the husbandry diet. Results indicate that raffinose in the diet is sufficient, but not required to see an increase NT-proBNP, but did not induce any changes in cardiac function after 5 weeks of feeding. Whether this could progress to reduction in cardiac function with longer term feeding is uncertain. A reduced cardiac function along with the greatest increase in NT-proBNP was observed after feeding the husbandry diet that contained the highest amount of insoluble fiber but did not contain legumes or oligosaccharide. Further research into the impact of insoluble fiber in the dental diet is needed to support these novel observations.

Increased NT-proBNP levels and cardiac ventricular function during aortic valve replacement (pilot study)

The objective was to study the relationship between the increased preoperative N-terminal segment of B-type natriuretic peptide precursor (NT-proBNP) blood levels and the parameters of the heart ventricles function, as well as the conditions for coronary perfusion of their myocardium before and after on-pump aortic valve replacement.Materials and methods. The study involved 27 patients aged 57.7±2.5 years who underwent aortic valve replacement. NT-proBNP blood level was determined before surgery. The level of NT-proBNP &gt; 1000 pg/ml was considered increased. Invasive hemodynamics, including the data of the right ventricle thermodilution volumetry, and transesophageal echocardiography data were analyzed at the stages: the 1st – after anesthesia induction, the 2nd – at the end of surgery. Logistic regression and ROC analysis were used for data processing.Results. Preoperative blood levels of NT-proBNP &gt; 1000 (3163.0[2507.25–7319]) pg/ml were recorded in 55.6% of patients. At the 1st stage, the biomarker increased level was associated with increased index of left ventricular end-systolic volume (OR 1.0955, 95% CI 1.0097–1.1885, p = 0.028, AUC 0.903), decreased left ventricular ejection fraction (OR 0, 9447, 95% CI 0.8949–0.9973, p = 0.040, AUC 0.753) and area contraction fraction (OR 0.8868, 95% CI 0.8086–0.9726, p = 0.011, AUC 0.890), increased mean pulmonary artery pressure (OR 1.1824, 95% CI 1.0020–1.3952, p = 0.047, AUC 0.722), and increased transpulmonary gradient (OR 1.4497, 95% CI 1.0103–2.0802, p = 0.044, AUC 0.810), increased right ventricular stroke work index (OR 1.5151, 95% CI 1.0319–2.2246, p = 0.034, AUC 0.761), and decreased coronary perfusion gradients of the left (OR 0.8961–0.9241, 95% CI 0.8229–0.9459 – 0.8630–0.9896, p = 0.012–0.024, AUC 0.793–0.861) and right (OR 0.9519, 95% CI 0.9136–0.9918, p = 0.019, AUC 0.847) ventricles. At the 2nd stage, NT-proBNP blood values &gt; 1000 pg/ml were associated with impaired left ventricular function, decreased mean arterial pressure (OR 0.9066, 95% CI 0.8264–0.9946, p = 0.038, AUC 0.761), and the vasopressor and inotropic support (OR 8.4000, 95% CI 1.2584–56.0694, p = 0.028, AUC 0.710).Conclusions. Prior to aortic valve replacement, the blood level of NT-proBNP &gt; 1000 pg/ml is associated with a moderate decrease in the left ventricular ejection fraction and area contraction fraction, an increased left ventricular end-systolic volume with a normal end-diastolic volume, an increased index of right ventricular stroke work in combination with moderately increased mean pulmonary artery pressure and increased transpulmonary gradient, as well as a decreased coronary perfusion gradients. At the end of operations, increased NT-proBNP blood level is associated with signs of impaired left ventricular contractility, a tendency to arterial hypotension, and the vasopressor and inotropic support. Increased preoperative NT-proBNP blood level are not associated with right ventricular volumes and ejection fraction both before and after on-pump aortic valve replacement.

Comparison and Validity of Fragmented QRS (fQRS) Against Cardiac Magnetic Resonance (CMR) in Predicting Right Heart Function in Tetralogy of Fallot Patients After Reconstructive Surgery

Background: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Patients with repaired TOF (rTOF) expose to moderate to severe pulmonary regurgitation (PR), right ventricular (RV) dysfunction, and RV failure. Although cardiac magnetic resonance (CMR) provides details of RV function and structure, an electrocardiogram (ECG) is accessible and inexpensive. Objectives: We aimed to assess the correlation between clinical symptoms and ECG parameters with CMR findings. Methods: This cross-sectional study assessed the patients with rTOF who underwent CMR between May 2020 and September 2022 in Imam Reza Hospital. The signs and symptoms of rTOF were assessed, and a pediatric cardiologist interpreted ECG parameters. We considered CMR findings, clinical symptoms, and ECG parameters with CMR findings in rTOF. In addition, fragmented QRS (fQRS), the additional spikes within the QRS complex, was used to indicate conduction disturbance due to myocardial scar or fibrosis. Data were analyzed by SPSS version 18. Results: Among 42 patients with rTOF, 20 patients were male. Although the QT correction (QTc) had a significant correlation with CMR parameters, fQRS showed a positive correlation with right ventricular ejection fraction (RVEF) less than 47% (OR 2.06, 95% CI 1.45 - 2.93; P-value = 0.005), right ventricular end-diastolic volume (RVEDV) more than 150 mL/m2 (OR 4.4, 95% CI 2.03 - 9.5; P-value = 0), and right ventricular end-systolic volume (RVESV) more than 80 mL/m2 (OR 2.83, 95% CI 1.59 - 5.04; P-value = 0). We found a murmur in the clinical examination of 64.3% of patients. Our results showed that tachycardia and tachypnea were the most common signs in these patients. Surgery at a young age was significantly correlated to lower ascending aortic volume, right pulmonary artery size, left pulmonary artery size, right atrium and left atrium volume, and main pulmonary artery flow. Conclusions: Compared to other ECG parameters, fQRS could strongly predict RVESV, RVEDV, and RVEF as the right heart indexes. Besides, repair surgery at a younger age reduces the possibility of needing pulmonary valve replacement surgery at older ages. Therefore, clinicians should consider these issues in patients.

Reduced myocardial strain of interventricular septum among male amateur marathon runners: a cardiac magnetic resonance study

ObjectivesTo analyze the long-term effect of multiple marathons on cardiac structure and function in amateur marathon runners compared with healthy controls. DesignCross-sectional study using male amateur marathon runners (n = 32) and age-matched cohort of male healthy controls (n = 12). MethodsA total of 32 male amateur marathon runners (age 44 ± 7 years) and 12 male healthy controls (age 42 ± 8 years) underwent cardiac magnetic resonance (CMR). The relevant parameters of cardiac structure and function were studied employing feature-tracking strain analysis. ResultsAmateur marathon runners showed lower heart rates, body mass index and body surface area. The left ventricular (LV) mass index, LV end-diastolic volume index and right ventricular end-systolic volume index were significantly higher in amateur marathon runners compared with healthy controls. Furthermore, walls of interventricular septum (IVS) in amateur marathon runners were thicker than healthy controls. There was no significant difference between two groups in the global myocardial strain (MS) in LV. However, the segmental radial and circumferential strains of the LV were lower in amateur marathon runners compared to healthy controls, specifically in the 8th and 9th segments. Finally, we also found as the total running intensity increased, so did global longitudinal strain. ConclusionsWe reported higher wall thickness and lower regional radial and circumferential strain in the IVS region in amateur marathon runners, suggesting that prolonged and high-intensity exercise may cause cardiac remodeling. Further studies are needed to investigate whether this is an adaptive or maladaptive change in amateur marathon runners.

Therapeutic potential of extracellular vesicles derived from cardiac progenitor cells in rodent models of chemotherapy-induced cardiomyopathy.

Current treatments of chemotherapy-induced cardiomyopathy (CCM) are of limited efficacy. We assessed whether repeated intravenous injections of human extracellular vesicles from cardiac progenitor cells (EV-CPC) could represent a new therapeutic option and whether EV manufacturing according to a Good Manufacturing Practices (GMP)-compatible process did not impair their bioactivity. Immuno-competent mice received intra-peritoneal injections (IP) of doxorubicin (DOX) (4 mg/kg each; cumulative dose: 12 mg/kg) and were then intravenously (IV) injected three times with EV-CPC (total dose: 30 billion). Cardiac function was assessed 9-11 weeks later by cardiac magnetic resonance imaging (CMR) using strain as the primary end point. Then, immuno-competent rats received 5 IP injections of DOX (3 mg/kg each; cumulative dose 15 mg/kg) followed by 3 equal IV injections of GMP-EV (total dose: 100 billion). Cardiac function was assessed by two dimensional-echocardiography. In the chronic mouse model of CCM, DOX + placebo-injected hearts incurred a significant decline in basal (global, epi- and endocardial) circumferential strain compared with sham DOX-untreated mice (p = 0.043, p = 0.042, p = 0.048 respectively) while EV-CPC preserved these indices. Global longitudinal strain followed a similar pattern. In the rat model, IV injections of GMP-EV also preserved left ventricular end-systolic and end-diastolic volumes compared with untreated controls. Intravenously-injected extracellular vesicles derived from CPC have cardio-protective effects which may make them an attractive user-friendly option for the treatment of CCM.

Effect of Head-Up/-Down Tilt on ECG Segments and Myocardial Temporal Dispersion in Healthy Subjects.

The head-up/-down tilt test acutely modifies the autonomic nervous system balance throughout a deactivation of the cardiopulmonary reflexes. The present study examines the influence of head-up/-down tilt on a number of ECG segments. A total of 20 healthy subjects underwent a 5 min ECG and noninvasive hemodynamic bio-impedance recording, during free and controlled breathing, lying at (a) 0°; (b) -45°, tilting up at 45°, and tilting up at 90°. Heart rate variability power spectral analysis was obtained throughout some ECG intervals: P-P (P), P-Q (PQ), PeQ (from the end of P to Q wave), Q-R peak (QR intervals), Q-R-S (QRS), Q-T peak (QTp), Q-T end (QTe), STp, STe, T peak-T end (Te), and, eventually, the TeP segments (from the end of T to the next P waves). Results: In all study conditions, the Low Frequency/High FrequencyPP and LFPP normalized units (nu) were significantly lower than the LF/HFRR and LFRRnu, respectively. Conversely, the HFPP and HFPPnu were significantly higher in all study conditions. STe, QTp, and QTe were significantly related to the PP and RR intervals, whereas the T wave amplitude was inversely related to the standard deviations of all the myocardial repolarization variables and to the left ventricular end-systolic volume (LVEDV). The T wave amplitude diminished during head-up tilt and significantly correlated with the LVEDV.

Phloretin ameliorates heart function after myocardial infarction via NLRP3/Caspase-1/IL-1β signaling

Objectives/AimsInflammation is crucial in structural and electrical remodeling after myocardial infarction (MI), affecting cardiac pump function and conduction pathways. Phloretin possesses an anti-inflammation role by inhibiting the NLRP3/Caspase-1/IL-1β pathway. However, the effects of Phloretin on cardiac contractile and electrical conduction function after MI remained unclear. Therefore, we aimed to investigate the potential role of Phloretin in a rat model of MI. MethodsRats were assigned into four groups: Sham, Sham+Phloretin, MI and MI+Phloretin, with ad libitum food and water. In the MI and MI+Phloretin groups, the left anterior descending coronary artery was occluded for 4 weeks, while the Sham and Sham+Phloretin groups received sham operation. The Sham+Phloretin group and the MI+Phloretin group received oral administration of Phloretin. In vitro, H9c2 cells were subjected to hypoxic conditions to simulate an MI model, with Phloretin for 24 h. Cardiac electrophysiological properties were assessed following MI, including the effective refractory period (ERP), action potential duration (APD)90 and ventricular fibrillation (VF) incidence. Echocardiography evaluated left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), left ventricular internal diameter at end-diastole (LVIDd), left ventricular internal diameter at end-systole (LVIDs), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) to assess cardiac function. Serum type B natriuretic peptide (BNP) level was applied to evaluate the degree of Heart failure (HF). The fibrosis area and severity were assessed by Masson staining and protein expression levels of collagen 3, collagen 1, TGF-β and α-SMA. Western blot analysis estimated the protein expression levels of NLRP3, Pro Caspase-1, Caspase-1, ASC, IL-18, IL-1β, pp38, p38, and Connexin43(Cx43) to elucidate the influence of inflammation on electrical remodeling after MI. ResultsOur findings demonstrate that Phloretin inhibits the NLRP3/Caspase-1/IL-1β pathway, leading to the upregulation of Cx43 by limiting p38 phosphorylation, which further decreases susceptibility to ventricular arrhythmias (VAs). Additionally, Phloretin attenuated fibrosis by inhibiting inflammation to prevent HF. In vitro experiments also provided strong evidence supporting the inhibitory effects of Phloretin on the NLRP3/Caspase-1/IL-1β pathway. ConclusionOur results suggest that Phloretin could suppress the NLRP3/Caspase-1/IL-1β pathway to reverse structural and electrical remodeling after MI to prevent the occurrence of VAs and HF.

A new assessment method for right ventricular diastolic function using right heart catheterization by pressure-volume loop.

Diastolic stiffness coefficient (β) and end-diastolic elastance (Eed) are ventricular-specific diastolic parameters. However, the diastolic function of right ventricle had not been investigated sufficiently due to the lack of established evaluation method. We evaluated the validity of these parameters calculated using only data of right heart catheterization (RHC) and assessed it in patients with restrictive cardiomyopathy (RCM) and cardiac amyloidosis. We retrospectively analyzed 46 patients with heart failure who underwent RHC within 10 days of cardiac magnetic resonance (CMR). Right ventricular end-diastolic volume and end-systolic volume were calculated using only RHC data, which were found to be finely correlated with those obtained from CMR. β and Eed calculated by this method were also significantly correlated with those derived from conventional method using CMR. By this method, β and Eed were significantly higher in RCM with amyloidosis group than dilated cardiomyopathy group. In addition, the β and Eed calculated by our method were finely correlated with E/A ratio on echocardiography. We established an easy method to estimate β and Eed of right ventricle from only RHC. The method finely demonstrated right ventricular diastolic dysfunction in patients with RCM and amyloidosis.

Safety and Efficacy of Istaroxime in Patients With Acute Heart Failure: A Meta-Analysis of Randomized Controlled Trials.

The aim of this study was to assess the efficacy and safety of istaroxime in patients with heart failure.Following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, a search was conducted on the EMBASE and Medline databases to identify articles related to the safety and efficacy of istaroxime in patients with heart failure. The search covered the period from inception to May 31st, 2023, without any restrictions on the year of publication.The search strategy utilized relevant terms such as "istaroxime," "heart failure", "efficacy," and other related terms, along with their corresponding Medical Subject Headings (MeSH) terms.The outcomes assessed in this meta-analysis included the change in left ventricular ejection fraction (LVEF), E to A ratio (a marker of left ventricle function), cardiac index in L/min/m2, systolic blood pressure (SBP) in mmHg, left ventricular end-systolic volume (LVESV) in ml, and left ventricular end-diastolic volume (LVDSV) in ml. For safety analysis, gastrointestinal events and cardiovascular events were assessed. A total of three randomized controlled trials (RCTs) were included in this meta-analysis encompassing 211 patients with heart failure. Pooled analysis showed that istaroxime was effective in increasing LVEF (MD: 1.26, 95% CI: 0.91 to 1.62, p-value: 0.001), reducing E to A ratio(MD: -0.39, 95% CI: -0.60 to -0.19, p-value: 0.001), increasing cardiac index(MD: 0.22, 95% CI: 0.18 to 0.25, p-value: 0.001), reducing LVESV (MD: -11.84, 95% CI: -13.91 to -9.78, p-value: 0.001), reducing LVEDV (MD: -12.25, 95% CI: -14.63 to -9.87, p-value: 0.001) and increasing SBP (MD: 8.41, 95% CI: 5.23 to 11.60, p-value: 0.001) compared to the placebo group. However,risk of gastrointestinal events was significantly higher in patients receiving istaroxime compared to the placebo group (RR: 2.64, 95% CI: 1.53 to 4.57, p-value: 0.0005). These findings support the enhancement of heart function with istaroxime administration, aligning with previous clinical and experimental evidence.

Reference Ranges and Development Patterns of Fetal Myocardial Function Using Speckle Tracking Echocardiography in Healthy Fetuses at 17 to 24 Weeks of Gestation.

The purposes of the study were to develop reference ranges and maturation patterns of fetal cardiac function parameters measured by speckle tracking echocardiography (STE) using multiple biometric variables at 17 to 24 weeks' gestation among Thai fetuses and to compare with other previous reports. The four-chamber view of the fetal heart in 79 healthy fetuses was suitably analyzed by STE to establish the best-fit regression model. The 95% reference intervals and Z-score equations of fetal cardiac function parameters were computed. The fractional area change of both ventricles, left ventricular (LV) end-diastolic and end-systolic volumes, LV stroke volume, LV cardiac output (CO), and LV CO per kilogram were all increased according to gestational age (GA) and five fetal biometric measurements. However, the global longitudinal strain, basal-apical length fractional shortening (BAL-FS), BAL annular free wall and septal wall FS, BAL free wall and septal wall annular plane systolic excursions, 24-segment transverse width FS, as well as LV ejection fraction were all independent of GA or other somatic characteristics. There were varying development patterns between fetal right and left ventricles of these cardiac function indices across the gestation period. Our study created Z-score and corresponding centile calculators, 5th and 95th centile reference tables, and corresponding graphs and determined the normal evolution across gestation using multiple somatic growth and age variables between 17 and 24 gestational weeks. These nomograms serve as an essential prerequisite for quantitatively evaluating fetal cardiac contractility and allow for precisely detecting early changes in the fetal heart function. · Most fetal cardiac function measurements were correlated with all the independent variables.. · Fetal ventricular function parameters have their own characteristic maturation changes.. · Racial variability may not occupy an important place for fetal myocardial function during these GA..