Index Of Left Ventricular Contractility Research Articles

Diagnostic utility of echocardiography and ultrasonography in buffaloes suffering from pericarditis

Pericarditis remains a serious problem faced by bovine producers in the developing countries. This study was designed to evaluate the echocardiographic and ultrasonographic changes in dairy buffaloes affected with pericarditis presented to Large Animal Clinic, Teaching Veterinary Hospital of Guru Angad Dev Veterinary and Animal Sciences University (GADVASU), Ludhiana, India. 49 buffaloes were included and selected on the basis one or more of the clinical signs viz., brisket edema, dyspnoea, muffled heart sounds and distended jugular veins. Animals were subjected to clinical examination, thoracic and abdominal ultrasonography and M- mode echocardiography. The CVS examination revealed normal intensity of heart sounds in 17 and muffled in 32 cases with splashing/pericardial rub in 9 cases. Ultrasonography revealed spleenic congestion, liver was congested in majority of the cases with visible dilatation of the caudal vena cava. Heart was normal in 7 and visibly compressed in 42 cases due to the pericardial fluid. Massive pleural fluid was seen in 28 cases. Buffaloes in our study had pericardial effusions (n=49), pleural and pericardial effusions (n=45) and pleural, pericardial and peritoneal effusions (n=19). The predominant echocardiographic findings were significantly decreased dimensions of the heart chambers in both systole and diastole. The left ventricular contractility indices (FS% and EF%) were significantly high. The clinical findings alone do not allow a definitive diagnosis of pericarditis as characteristic signs were not present in all the cases. The combined use of ultrasonography and echocardiography provides a comprehensive idea about such cases and aids in early diagnosis of pericarditis.

Remodelling and functional features of the left ventricle in miners

Introduction. Diseases of the circulatory system are the main cause of mortality in the employable population. Preserving occupational longevity involves the identification of early signs of myocardial damage by modern techniques, which will allow taking a fresh look at the prevention of cardiovascular pathology in people engaged in harmful working conditions. Materials and methods. The study included two hundred thirty six miners of average age of 47.1±0.36 years who underwent periodic medical examination at the Institute clinic. The work experience in hazardous occupation conditions was 22.7±0.6 years. The study was based on transthoracic echocardiography using tissue Dopplerography and speckle tracking technology. Results. Concentric remodelling of the left ventricle was detected in 25.9% of the miners. Arterial hypertension was revealed in 65.6% of the miners with concentric remodelling of the left ventricle versus 34.3% of the miners with its normal geometry (p=0.00002). There were no significant differences in the left ventricular contractile function indices in the groups. In both groups, diastolic dysfunction type 1 was predominantly detected, which was significantly more common in the miners with concentric remodelling of the left ventricle (62.3% and 42.0%, p=0.006). Pseudonormal type of diastolic dysfunction occurred in 8.2% of the group with concentric remodelling versus 5.14% with normal left ventricular geometry, p= 0.38. Limitations. The study was limited by the number of the examined persons undergoing periodic medical examination at the Research Institute for Complex Problems of Hygiene and Occupational Diseases. Conclusion. Remodelling of the left ventricular myocardium in miners did not correlate with a decrease in the longitudinal deformation of the left ventricle, which indicates the possible influence of harmful occupational factors on the development of its systolic dysfunction. Diastolic dysfunction of the left ventricle had a clear relationship with remodelling of the left ventricular myocardium. In this regard, it is recommended to conduct echocardiography during an in-depth periodic medical examination of miners with long-term work experience to identify a risk group for developing cardiovascular accidents.

The additive prognostic value of end-systolic pressure-volume relation by stress CMR in patients with known or suspected coronary artery disease.

The difference between rest and peak stress end-systolic pressure-volume relation (ΔESPVR) is an afterload-independent index of left ventricular (LV) contractility. We assessed the independent prognostic value of ΔESPVR index by dipyridamole stress-cardiovascular magnetic resonance (CMR) in patients with known/suspected coronary artery disease (CAD). We considered 196 consecutive patients (62.74 ± 10.66years, 49 females). Wall motion and perfusion abnormalities at rest and peak stress were analysed. Replacement myocardial fibrosis was detected by late gadolinium enhancement(LGE) technique. The ESPVR was evaluated at rest and peak stress from raw measurement of systolic arterial pressure and end-systolic volume by biplane Simpson's method. A reduced ΔESPVR index (≤ 0.02mmHg/mL/m2) was found in 88(44.9%) patients and it was associated with a lower LV ejection fraction(EF) and with a higher frequency of abnormal stress CMR and myocardial fibrosis. During a mean follow-up of 53.17 ± 28.21months, 50(25.5%) cardiac events were recorded: 5 cardiac deaths, 17 revascularizations, one myocardial infarction, 23 hospitalisations for heart failure or unstable angina, and 4 ventricular arrhythmias. According to Cox regression analysis, diabetes, family history, LVEF, abnormal stress CMR, myocardial fibrosis, and reduced ΔESPVR were significant univariate prognosticators. In the multivariate analysis the independent predictors were ΔESPVR index ≤ 0.02mmHg/mL/m2 (hazard ratio-HR = 2.58, P = 0.007), myocardial fibrosis (HR = 2.13, P = 0.036), and diabetes (HR = 2.33, P = 0.012). ΔESPVR index by stress-CMR was independently associated with cardiac outcomes in patients with known/suspected CAD, in addition to replacement myocardial fibrosis and diabetes. Thus, the assessment of ΔESPVR index may be included into the standard stress-CMR exam to further stratify the patients.

Evaluation of the translation of multiple cardiovascular regulatory mechanisms in the anesthetized dog

The strategic and targeted use of an anesthetized canine cardiovascular model early in drug discovery enables a comprehensive cardiovascular and electrophysiological assessment of potential safety liabilities and guides compound selection prior to initiation of chronic toxicological studies. An ideal model would enable exposure-response relationships to guide safety margin calculations, have a low threshold to initiate, and have quick delivery of decision quality data. We have aimed to profile compounds with diverse mechanism of actions (MoAs) of “non-QT” cardiovascular drug effects and evaluate the ability of nonclinical in vivo cardiovascular models to detect clinically reported effects. The hemodynamic effects of 11 drugs (atropine, itraconazole, atenolol, ivabradine, milrinone, enalaprilat, fasudil, amlodipine, prazosin, amiloride, and hydrochlorothiazide) were profiled in an anesthetized dog cardiovascular model. Derived parameters included: heart rate, an index of left ventricular contractility, mean arterial pressure, systemic vascular resistance, and cardiac output. Species specific plasma protein data was generated (human, dog) and utilized to calculate free drug concentrations. Using the anesthetized dog cardiovascular model, 10 of the 11 drugs displayed the predicted changes in CV parameters based on their primary MoAs and corresponding clinically described effects. Interestingly but not unexpected, 1 of 11 failed to display their predicted CV pattern which is likely due to a delay in pharmacodynamic effect that is beyond the duration of the experimental model (hydrochlorothiazide). The analysis from the current study supports the strategic use of the anesthetized dog model early in the drug discovery process for a comprehensive cardiovascular evaluation with good translation to human.

Usefulness of tissue Doppler-derived left ventricular isovolumic contraction velocity in patients with heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is a group of diseases classified by left ventricular (LV) EF, a measure of pump function. However, LVEF does not reflect LV contractility. Previous studies have shown that tissue Doppler-derived LV isovolumic contraction velocity (IVCv) correlates well with the LV peak dP/dt, an index of LV contractility. We explored whether LV IVCv is associated with 1-year post-discharge outcomes in HFpEF. We enrolled 113 patients (median age, 86 years, 45 male) with HFpEF (EF on admission ≥ 50%) who were admitted to our hospital for the treatment of acute HF. Clinical characteristics including echocardiographic data were obtained before discharge. IVCv was obtained from the tissue Doppler waveforms of both the septal and lateral mitral annulus of the apical 4-chamber view and averaged data were used. Primary outcomes were all-cause death or unplanned hospitalization due to HF within the first year. Among all patients, median LVEF was 61%, left atrial diameter was 47mm, E/e' was 17.5, and IVCv was 4.5cm/sec; mean tricuspid regurgitation velocity was 2.6m/sec. Regarding laboratory data, the median plasma B-type natriuretic peptide level was 185pg/mL. Thirty-four events occurred (15 deaths, 19 unplanned hospitalizations due to HF) within the first year. In multivariate Cox proportional hazards analyses, IVCv was significantly associated with outcomes (hazard ratio .68, 95% confidence interval .50-.89, p=.0095), independent of general characteristics, echocardiographic measures and pertinent laboratory parameters. LV IVCv was independently associated with 1-year outcomes in patients with HFpEF.

The relationship between diabetes, obesity and cardiovascular disease phenotypes: a UK Biobank cohort study

Abstract Background Obesity and diabetes mellitus (DM) frequently co-exist, yet their individual contributions to cardiovascular risk remain debated. Purpose We explored cardiovascular disease biomarkers, events and mortality in a large cohort stratified by body mass index (BMI) and DM. We hypothesised that DM with normal BMI is associated with a cardiovascular phenotype and event rate comparable to obesity without DM. Methods 451,355 UK Biobank participants were stratified by ethnicity-specific BMI categories (normal, overweight, obese) and DM status. We examined cardiovascular biomarkers including: carotid intima-media thickness (CIMT); arterial stiffness; left ventricular ejection fraction (LVEF) and cardiac contractility index (CCI). Poisson regression models estimated adjusted incidence rate ratios (IRR) for myocardial infarction, ischaemic stroke and cardiovascular death, with normal weight non-DM as comparator. Correlation matrices of Poisson model’s coefficients were used to assess correlations between covariates. Results 5% of participants had DM (10% normal weight, 34% overweight and 55% obese; versus 34%, 43% and 23%, respectively, in non-DM). In the non-DM group, overweight/obesity was associated with higher CIMT, arterial stiffness and CCI, and lower LVEF (p<0.05); these relationships were diminished in the DM group. Within BMI classes, DM was associated with adverse cardiovascular phenotype (p<0.05), particularly in the normal weight group. After 5,323,190 person-years follow-up, incident myocardial infarction, ischaemic stroke and cardiovascular mortality all rose across increasing BMI categories in the DM and non-DM groups (p<0.05). However, normal weight DM had higher cardiovascular mortality than obese non-DM (IRR 2.81 [95% confidence interval: 2.24-3.54] vs IRR 1.84 [1.70-1.98]). Pairwise correlation analysis demonstrated the strongest correlates of cardiovascular parameters were markers of adiposity; this was apparent in the DM and non-DM groups, although these remained modest with Pearson’s correlation coefficients of no more than 0.25. Conclusions Obesity and DM are additively associated with adverse cardiovascular biomarkers and mortality risk. Whilst adiposity metrics are more strongly correlated with cardiovascular biomarkers than diabetes-oriented metrics, both correlate weakly, suggesting other factors underpin the high cardiovascular risk of normal-weight diabetes. Ideal target range for metrics of adiposity may therefore be lower than currently proposed in people with DM.Table 1:Adjusted IRR of CV deathFigure 1:KM Curve for CV death

Abstract 13550: Prognostic Value of the Global Left Ventricular Contractility Index in Patients With Severe Mitral Regurgitation and Preserved Left Ventricular Ejection Fraction

Introduction: Global left ventricular (LV) contractility index, dσ*/dt max , defined as the maximal rate of change of pressure-normalized LV wall stress, is given by the formula 3(dV/dt) max /2V m where dV/dt max is the product of left ventricular outflow tract (LVOT) velocity and area; and V m , left ventricular mass index (LVMI). In published reports, prediction of clinical outcomes in aortic stenosis were observed. It is unknown if dσ*/dt max would predict clinical outcomes in patients with severe mitral regurgitation (MR). Aim: We studied the association of dσ*/dt max with clinical outcomes in severe MR with preserved LV ejection fraction (EF). Methods: Consecutive patients with severe MR and LVEF ≥50% diagnosed on index echocardiogram at a single centre were retrospectively analyzed. Patients with other valvular lesions of moderate severity or more, or valvular interventions, were excluded. Clinical outcomes were ascertained by review of medical records. The primary outcome was a composite of heart failure hospitalizations and all-cause mortality. Results: 176 patients were included in the analysis. Table 1 depicts the characteristics of the study population. Patients with composite outcomes were older, more likely to be female, had higher LVMI, lower regurgitation volume and dσ*/dt max (2.2 +/- 0.7 vs 2.7 +/- 0.9, p = 0.02). On multivariable Cox regression (Table 2), only age and dσ*/dt max (adjusted HR 0.42, 95% CI: 0.220 - 0.806, p = 0.01) remained independently associated with occurrence of the primary outcome. Conclusions: In patients with isolated severe mitral regurgitation and preserved LVEF, low dσ*/dt max was an independent predictor of adverse clinical outcomes.

Peculiarities of the structural and functional state of the heart in patients with arrhythmias depending on the severity of cognitive disorders

Background. The purpose of our work was to find out the dependence of changes in the cognitive sphere on the features of the structural and functional state of the heart and central hemodynamics in patients with arrhythmias. Material and methods. We have examined 139 patients with different clinical forms of arrhythmias. All of them underwent extended neuropsychological testing and central hemodynamic studies. The state of central hemodynamics was assessed by an ultrasound examination of the heart. The state of intracardiac hemodynamics, structural changes in various parts of the heart were evaluated; based on this, the type of heart remodeling was determined. Correlations of hemodynamic indicators with the results of neuropsychological testing were evaluated. Results. In patients with mild cognitive disorders (CD), the left ventricular myocardial contractility index did not differ significantly from that in patients without CD, but in people with moderate CD it was 9.6 % lower (p = 0.044). With moderate CD, the dilatation of the left parts of the heart increased (end-diastolic volume — by 16.5%, p =0.049; left atrium — by 9.9 %, p = 0.049), which, along with increased hypertrophy of the interventricular septum by 12.8 % (p = 0.048) and of the left ventricular posterior wall by 12.9 % (p = 0.048), led to an increase in the pulmonary artery pressure by 24.8 % (p = 0.015). Among patients with CD, concentric (42.2 %) and eccentric (22.6 %) left ventricular hypertrophy was more often detected (p = 0.048 and p = 0.027); in those without CD, concentric remodeling of the left ventricle prevailed (p = 0.037). In patients with mild CD, higher stroke volume was recorded — by 8.3 % (p = 0.049) compared to those without CD. However, according to indicators of cardiac output, cardiac index and total peripheral vascular resistance, differences were unreliable (p > 0.05). Patients with moderate CD reported an increase in stroke volume and cardiac output by 7.6 (p = 0.043) and 14.9 % (p = 0.014), respectively, compared to those without CD. Indicators of central hemodynamics had the greatest impact on the sphere of attention, regulatory functions, visual-spatial and mnestic deficits. The highest odds ratio for the development of CD were found for left ventricular ejection fraction (2.52, 95% confidence interval: 1.82–3.29, p < 0.001). Conclusions. The identified associations of cognitive dysfunction, central hemodynamics and heart remodeling are important for optimizing an individualized approach to patient management and predicting the development of CD.

Thermal and Cardiovascular Responses During a Very Hot and Dry Heatwave Simulation in Young and Older Adults

Heatwaves cause disproportionately high mortality rates in those aged ≥ 65 years. While age differences in the cardiovascular responses to heat stress have been investigated, previous studies used a water-perfused suit to elicit heat stress. Therefore, how aging affects the cardiovascular responses to prolonged environmental heat stress is not fully understood. Purpose: We tested the hypothesis that 3 hours of exposure to a very hot and dry heat wave condition would increase core temperature and left ventricular systolic contractility (s’) to a greater extent in older, compared with younger adults. Methods: Healthy young (n = 13, 6F/7M, 29±4 years, 1.82±0.13 m-2) and older (n = 19, 10F/9M, 70±4 years, 1.85±0.18 m-2) adults were exposed to 47°C, 15% humidity) for 3-hours, interspersed with seven 5-minute bouts of physical activity at 3 METS to replicate heat generation associated with activities of daily living. Core temperature, brachial blood pressure and heart rate were monitored continuously during heating. Echocardiograms were obtained at baseline (in a thermoneutral environment) and at three hours into heat stress (i.e., post-heat wave) to assess s’. Drinking water was provided throughout the protocol to minimize dehydration. The magnitude of the change in each variable from baseline to post-heatwave between age groups was compared using independent samples t-tests. The association between the change in core temperature and the change in s’ was assessed with linear regression. Results: From baseline to 3-hour heatwave exposure, there was a greater increase in core temperature (Δ1.36±0.28 vs Δ0.74±0.28 °C, p < 0.0001) and s’ (Δ3.3±2.2 vs Δ1.6±1.8 cm/s, p = 0.011) in older, compared with younger subjects, respectively. However, the magnitude of the change in core temperature was not associated with the increase in s’ in older of young subjects (R2 = 0.065 and 0.120, respectively). The older subjects showed a greater decrease in mean arterial pressure compared with younger subjects (-14±10 vs -4±7 mmHg, p = 0.004). Heart rate increased similarly in older and young subjects (27±13 vs 27±12 b/min, p = 0.412). Conclusions: Our findings suggest that an index of left ventricular systolic contractility (s’) increases to a greater extent in older, compared with younger subjects. The change in s’ was not associated with the change in core temperature in either age group. Supported by NIH R01AG069005 (CGC), F32HL154559 & K01HL160772 (JCW), and F32HL154565 (LNB). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Is perfusion index a surrogate indicator of left ventricular contractility in neonates? A prospective study.

Noninvasive blood pressure monitoring may not accurately reflect cardiac contractility in neonates due to low vascular tone. The perfusion index (PI) is a noninvasive method of assessing the strength of peripheral pulses. It is shown to have a significant correlation with the left ventricular output. This prospective study estimates the correlation between PI and cardiac contractility in neonates. All hemodynamically stable neonates who were on substantial enteral feeds and not on any respiratory or inotropic support underwent measurement of PI and echocardiography examination. Various indices of left ventricular contractility were estimated, and the correlation coefficient between them and PI was determined. Fifty-six neonates were studied. The median (interquartile range [IQR]) PI was 1.5 (1.25-1.75). The median (IQR) PI in preterm neonates was 1.5 (1.2-1.8) and that in term neonates was 1.8 (1.25-2.7) (P = 0.064). PI had a correlation of 0.205 with fractional shortening (P = 0.129) and 0.13 with left ventricular ejection fraction (P = 0.821). The Spearman's correlation coefficient between PI and velocity of circumference fiber shortening was 0.009 (P = 0.945). The Spearman's correlation coefficient between PI and cardiac output was -0.115 (P = 0.400). The PI does not correlate with left ventricular contractility parameters in neonates.

Relationship between left ventriculoarterial coupling and damage stage in severe aortic stenosis

Abstract Background In patients with severe aortic stenosis (AS), an anatomic and functional staging classification has been proposed to assess extent of cardiac chambers damage to improve the decision of aortic valve replacement based only in symptoms or ejection fraction (EF) <50%. This staging relies on the concept that left ventricular (LV) afterload secondary to AS induce LV dysfunction with progression to LV and right ventricular damage. However, afterload has valvular and vascular components, and the latter is not evaluated by the classification of stages. Characteristics of arterial vasculature can impact on LV function through the alteration in LV-VA coupling which is the relationship between effective arterial elastance (Ea) and LV end-systolic elastance (Emax). Objective To evaluate the relationship between LV-VA coupling and the different stages of cardiac damage in severe AS. Methods We studied 205 patients, age average 70±11 years, 117 men, with severe AS (AVA <1 cm2) with Doppler echocardiography. Measurements of cardiac chambers were made according to ASE/EACVI Guidelines. Ea was calculated as end-systolic pressure divided by stroke volume. End-systolic pressure was obtained from tonometry of carotid pulse. Emax was estimated by the method of Senzaki (1) as an index of LV contractility. Ea / Emax ratio was used to assess LV-VA coupling. Patients were divided in five groups according to the classification of staging cardiac damage proposed by Tasted (2): stage 0, no valvular cardiac damage; stage 1, LV damage (EF <60%); stage 2, left atrial or mitral valve damage; stage 3, pulmonary vasculature or tricuspid valve damage and stage 4, right ventricular damage, or subclinical heart failure (LV stroke volume index <30 ml/m2). Results Mean ± standard deviation (see Table 1). No patient was in stage 0. Symptoms was present in 40% of stage 1, 85% of stage 2 and 100% of stage 3 and 4. Ea increases from stage 2 to stage 4 while Emax did not change in those groups but decreased from stage 1 to 2. Consequently, LV-VA coupling progressively decreased from stage 1 to 4. Conclusions Worsening of LV-VA coupling increase with staging cardiac damage. The alteration of LV-VA coupling from stage 2 to 4 is due to an increase in Ea without significant changes in level of contractility (Emax). The progression of cardiac damage appears to be related not only to valve disease but also to the characteristics of arterial vasculature. Funding Acknowledgement Type of funding sources: None.

Therapeutic Efficacy of Carvedilol and Hawthorn Extract in Management of Dilated Cardiomyopathy in Dogs

The present study was undertaken to evaluate the effect of carvedilol and hawthorn extract in managing dilated cardiomyopathy (DCM) to limit the treatment cost and improve the quality of pet life. Total 165 dogs were subjected to detailed clinical and physical examination, electrocardiography and echocardiography. Out of 165 dogs, 61(36.96%) were diagnosed as DCM, out of which 30 were allocated randomly to three treatment groups comprising ten dogs in each group. Group-I dogs were treated with pimobendan, digoxin, enalapril and furosemide. In Group-II and III, pimobendan was replaced with carvedilol and hawthorn extract, respectively. Dogs with ventricular arrhythmias (Ventricular Premature Complexes, Ventricular fibrillation) were excluded from the treatment groups as digoxin is contraindicated in ventricular arrhythmias. A noticeable improvement in clinical signs, thoracic radiographic findings, left ventricular dimensions and left ventricular contractility indices was observed in the three treatment groups after 28 days of treatment when compared to the pre-treatment values. The drug's therapeutic efficacy was evaluated based on comparative assessment of post treatment left ventricular contractility indices (fractional shortening and ejection fraction). Group I had longer survival time with mean of 375 ± 14.25 days followed by Group III (264.67 ± 41.22 days) and Group II (214.57 ± 31.32 days) dogs.

Incidence of acute myocardial injury and its association with left and right ventricular systolic dysfunction in critically ill COVID-19 patients

BackgroundPrevious studies have found an increase in cardiac troponins (cTns) and echocardiographic abnormalities in patients with COVID-19 and reported their association with poor clinical outcomes. Whether acute injury occurs during the course of critical care and if it is associated with cardiac function is unknown.The purpose of this study was to document the incidence of acute myocardial injury (AMInj) and echocardiographically defined left ventricular (LV) and right ventricular (RV) systolic dysfunction in consecutive patients admitted to an intensive care unit (ICU) for COVID-19. The relationship between AMInj and echocardiographic abnormalities during the first 14 days of ICU admission was studied. Finally, the association between echocardiographic findings, AMInj and clinical outcome was evaluated.MethodsSeventy-four consecutive patients (≥18 years) admitted to the ICU at Linköping University Hospital between 19 Mar 2020 and 31 Dec 2020 for COVID-19 were included. High-sensitivity troponin-T (hsTnT) was measured daily for up to 14 days. Transthoracic echocardiography was conducted within 72 h of ICU admission. Acute myocardial injury was defined as an increased hsTnT > 14ng/l and a > 20% absolute change with or without ischaemic symptoms. LV and RV systolic dysfunction was defined as at least 2 abnormal indicators of systolic function specified by consensus guidelines.ResultsIncreased hsTnT was observed in 59% of patients at ICU admission, and 82% developed AMInj with peak levels at 8 (3–13) days after ICU admission. AMInj was not statistically significantly associated with 30-day mortality but was associated with an increased duration of invasive mechanical ventilation (10 (3–13) vs. 5 days (0–9), p=0.001) as well as ICU length of stay (LOS) (19.5 (11–28) vs. 7 days (5–13), p=0.015). After adjustment for SAPS-3 and admission SOFA score, the effect of AMInj was significant only for the duration of mechanical ventilation (p=0.030).The incidence of LV and RV dysfunction was 28% and 22%, respectively. Only indices of LV and RV longitudinal contractility (mitral and tricuspid annular plane systolic excursion) were associated with AMInj. Echocardiographic parameters were not associated with clinical outcome.ConclusionsMyocardial injury is common in critically ill patients with COVID-19, with AMInj developing in more than 80% after ICU admission. In contrast, LV and RV dysfunction occurred in approximately one-quarter of patients. AMInj was associated with an increased need for mechanical ventilation and ICU LOS but neither AMInj nor ventricular dysfunction was significantly associated with mortality.

Promotion of aging heart function and its redox balance following hind-limb blood flow restriction plus endurance exercise training in rats: klotho and PGC1-α as involving candidate molecules.

Mild to moderate-intensity endurance exercise training combined with hind-limb blood flow restriction (BFR) induces elderly heart rejuvenation and improves cardiac inotropy and resistance to ischemia. However, the mediators of these beneficial effects are still not well known. The present study investigated the possible role of some important molecules in the mediatory of this model of exercise training in the promotion of heart health in aged rats. Male old Wistar rats randomly were divided into control-sham (CTL), hind limbs blood flow restriction (BFR), sham-operated plus 10weeks' treadmill exercise training (Ex), and BFR plus exercise (BFR + Ex) groups. Left ventricular end-diastolic pressure (LVEDP), contractility, and Tau indices were measured. ELISA and western blot tests were used for measuring determined cardiac biochemical factors. BFR + Ex displayed significantly lower LVEDP (P < 0.05 and P < 0.01 vs. Ex, and other groups, respectively), improved heart cardiac contractility (P < 0.01), and significantly reduced Tau index in comparison with other groups. BFR + Ex significantly reduced both BAX and BAX to BCL2 ratio (P < 0.05) and as well MDA to TAC ratio (P < 0.05, compared to the CTL group). Also, BFR + Ex significantly increased the level of klotho (P < 0.05) and PGC1-α (P < 0.001) proteins compared to the CTL group but had no significant effect on P-STAT3 expression. Exercise training alone increased Apelin protein (P < 0.05). Our findings suggest that mild to moderate BFR endurance training improves heart performance in the aging rat partly through ameliorating apoptosis, recovering redox balance, improving the longevity factor klotho, and increasing the key energy metabolism regulator PGC1-α.

Protective Effect of Rutin Trihydrate Against Dose-Dependent, Cisplatin-Induced Cardiac Toxicity in Isolated Perfused Rat's Heart.

BackgroundCisplatin is a common anticancer drug with potential cardiac and renal toxicities. Rutin, a natural compound present in various medicinal plants, has been shown to protect against chemotherapy-induced toxicities. In this study, we explored the protective effect of rutin against the dose-dependent cardiotoxic effects of cisplatin such as perfusion pressure, histopathologic effect on the myocardium, and oxidative stress in isolated perfused rat hearts.MethodologyThe cardiotoxic effects of cisplatin were studied at three dosages (1, 7, and 14 mg/L) in isolated perfused rat hearts. The dose-dependent, cisplatin-induced toxic effects on left ventricular pressure (LVP), heart rate (HR), dp/dt (maximum), dp/dt (minimum), perfusion pressure, pressure-time index, contractility index, and duration of diastole were assessed. The effects of cisplatin were measured one minute before perfusion of cisplatin and 60 minutes after perfusion of the isolated rat hearts.ResultsCisplatin (1-14 mg/L) caused a significant (p < 0.05) dose-dependent reduction in LVP. The percentage LVP values reduced from 94 ± 9 (control untreated hearts) to 70 ± 6, 69 ± 5, and 65 ± 4 in hearts treated with 1, 7, and 14 mg/L of cisplatin, respectively. Similarly, cisplatin at similar doses caused a marked reduction in the values of dp/dt (maximum), dp/dt (minimum), and pressure-time index in isolated rat hearts. The respective percentage values of these parameters compared to those of untreated hearts were significantly reduced from 101 ± 7 to 72 ± 5, 92 ± 8 to 69 ± 4, and 92 ± 12 to 57 ± 7 in hearts treated with 14 mg/L of cisplatin. Perfusion of hearts with rutin trihydrate (1 µM/L) 10 minutes before administration of cisplatin and throughout the experiment attenuated the detrimental effects of cisplatin on cardiac functions in isolated rat hearts (p < 0.05). In addition, cisplatin-induced degeneration and necrosis of cardiac muscle cells reduced with the concurrent administration of rutin and restored normal heart histology. Moreover, cisplatin-induced reduction in glutathione and increased level of malondialdehyde in the myocardium was reversed by concurrent administration of rutin in isolated rat hearts.ConclusionsCisplatin produced a dose-dependent impairment of several parameters of cardiac function such as LVP, contractility index, and pressure-time index. It caused histopathological alterations in isolated rat hearts. These harmful effects of cisplatin were suppressed by rutin trihydrate, suggesting the potential protective effects of rutin against cisplatin-induced cardiotoxicity. Rutin trihydrate also improved the reduced glutathione contents and suppressed the malondialdehyde contents in the cardiac tissue of isolated rat hearts, suggesting that the observed beneficial effects of rutin trihydrate in this study could be related to its antioxidant properties.

Laboratory and instrumental indicators associated with decreased left ventricle ejection fraction in patients with chronic heart failure

Objectives to evaluate laboratory and instrumental indicators, associated with decreased left ventricle ejection fraction in patients with heart failure of ischemic etiology.&#x0D; Material and methods. The observational study included 71 patient with coronary heart disease and chronic heart failure (CHF). All patients underwent the testing on the following parameters: uric acid concentration, C-reactive protein (hs-CRP), NT-proBNP, ST2 and cystatin C tests, glomerular filtration rate. Instrumental examination included transthoracic echocardiography and 6-minute walk test.&#x0D; Results. The study revealed several indicators, associated with decreased left ventricle ejection fraction less than 50% in patients with CHF: NT-proBNP level 822.2 pg/ml, ST2 38.61 ng/l, uric acid 419.9 mmol/l, hs-CRP 2.54 mg/l, end diastolic volume index 73.68 ml/m2, left ventricular mass index 127 g/m2, left ventricular contractility index 1.75, pulmonary artery pressure 29 mm Hg. and vena cava inferior diameter 20 mm.

Flow manipulation and the association with myocardial contractility during extracorporeal life support (FLAME)

Abstract Funding Acknowledgements Type of funding sources: None. Background Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is an advanced technique in extracorporeal life support (ECLS) used to support extreme circulatory failure including patients with cardiac arrest and cardiogenic shock refractory to conventional support. It is a long-standing belief that peripheral V-A ECMO poses increased afterload to the inured heart, but conventional echocardiographic measurements are often insensitive in detecting subtle changes in loading conditions. Purpose This study aimed to evaluate the effects of varying blood flow during peripheral V-A ECMO on intrinsic myocardial contractility, using detailed echocardiographic assessment including speckle tracking echocardiography (STE). Methods Adult patients with acute cardiogenic shock who were supported by peripheral V-A ECMO from April 2019 to September 2020 were recruited. Serial hemodynamic and cardiac performance parameters were measured by transthoracic echocardiogram (TTE) within 48 hours after implementation of V-A ECMO, at different levels of extracorporeal blood flow – 100%, 120% and 50% of target blood flow (TBF). Results A total of 30 patients were included. 22 (71%) were male, and the mean (SD) age was 54 (13) years. The major indications for V-A ECMO were myocardial infarction (19, 63% patients), and myocarditis (5, 17%). With a decrease in extracorporeal blood flow from 100% to 50% of TBF, mean arterial pressure (MAP) dropped from 76+/-3 to 64+/-3mmHg (p &amp;lt;0.001), and cardiac index (CI) increased from 0.89+/-0.13 to 1.27+/-0.18L/min/m2 (p &amp;lt; 0.001). All indices of left ventricular contractility improved at a lower extracorporeal blood flow: the myocardial contractility measured by global longitudinal peak systolic strain (GLPSS) improved from -3+/-0.7% to -5+/-0.8% (p &amp;lt; 0.001); left ventricular ejection fraction (LVEF) increased from 21.5+/-2.6% to 30.9+/-2.7% (p &amp;lt; 0.001) and 19.7+/-3.1% to 28.4+/-3.2% (p &amp;lt; 0.001) by biplane and linear methods, respectively; left ventricular index of myocardial performance (LIMP) improved from 1.51+/-0.12 to 1.03+/-0.09 (p &amp;lt; 0.001). Similar findings were reproduced when comparing left ventricular contractility at extracorporeal blood flows of 120% and 50% of TBF. Conclusions The ECMO blood flow rate in peripheral V-A ECMO is inversely related to myocardial contractility, and is quantifiable by myocardial strain measured by STE.

Incorporating the anterior mitral leaflet to the annulus impairs left ventricular function in an ovine model

ObjectivesTranscatheter mitral valve prostheses are designed to capture the anterior leaflet and surgical techniques designed to fully preserve the subvalvular apparatus at prosthetic valve insertion both serve to shorten the anterior mitral leaflet height, thus effectively incorporating it into the anterior annulus. This study quantifies the acute effects of incorporating the anterior mitral leaflet into the annulus on left ventricular function. MethodsFourteen adult sheep (weight, 48.7 ± 6.2 kg) underwent a mechanical mitral valve insertion on normothermic beating-heart cardiopulmonary bypass, with full retention of the native mitral valve but with placement of exteriorized releasable snares around the anterior mitral leaflet. Continuous measurements of left ventricular mechano-energetics were recorded throughout, alternating incorporating and releasing of the anterior mitral leaflet to the mitral annulus. Echocardiography confirmed the incorporation into the annulus and release. ResultsThe independent indices of left ventricular contractility (ie, end systolic pressure volume relationship and preload recruitable stroke work) were both significantly impaired when the anterior mitral leaflet was incorporated to the annulus and restored after release, as were the hemodynamic parameters: cardiac output, stroke volume, stroke work, and left ventricular pressure decreased by 15%, 17%, 23%, and 11%, respectively. Echocardiography demonstrated increased sphericity of the left ventricle during anterior mitral leaflet incorporation. ConclusionsIncorporating the anterior mitral leaflet to the anterior annulus adversely affected left ventricular contractility, caused distortion of the left ventricle in the form of increased sphericity, and impaired hemodynamic parameters in normal ovine hearts.

Aortic acceleration as a noninvasive index of left ventricular contractility in the mouse

The maximum value of the first derivative of the invasively measured left ventricular (LV) pressure (+ dP/dtmax or P′) is often used to quantify LV contractility, which in mice is limited to a single terminal study. Thus, determination of P′ in mouse longitudinal/serial studies requires a group of mice at each desired time point resulting in “pseudo” serial measurements. Alternatively, a noninvasive surrogate for P′ will allow for repeated measurements on the same group of mice, thereby minimizing physiological variability and requiring fewer animals. In this study we evaluated aortic acceleration and other parameters of aortic flow velocity as noninvasive indices of LV contractility in mice. We simultaneously measured LV pressure invasively with an intravascular pressure catheter and aortic flow velocity noninvasively with a pulsed Doppler probe in mice, at baseline and after the administration of the positive inotrope, dobutamine. Regression analysis of P′ versus peak aortic velocity (vp), peak velocity squared/rise time (vp2/T), peak (+ dvp/dt or v′p) and mean (+ dvm/dt or v′m) aortic acceleration showed a high degree of association (P′ versus: vp, r2 = 0.77; vp2/T, r2 = 0.86; v′p, r2 = 0.80; and v′m, r2 = 0.89). The results suggest that mean or peak aortic acceleration or the other parameters may be used as a noninvasive index of LV contractility.

Correlations between morphological features of intracoronary thrombi and left ventricular structure and function in patients with ST-segment elevation myocardial infarction

The majority of cases of acute ST-elevation myocardial infarction (STEMI) are caused by the rupture of an atherosclerotic plaque and subsequent thrombus formation. The study of clot structure may be important for the prediction of further course of the disease. The study included 100 patients with STEMI who underwent primary percutaneous coronary intervention (PCI) with manual thromboaspiration within the first 12 hours after the onset of symptoms. Sufficient aspiration material for histological examination was obtained in 97 patients. These intracoronary thrombi were investigated macroscopically and microscopically. Subsequently, correlations between morphological structure of thrombi and structural and functional features of the myocardium after revascularization were analyzed. Pathological QS pattern was detected in 45 (46.39±5.06%) patients. Peripheral infiltration of intracoronary thrombus with neutrophils was the only morphological feature associated with the presence of QS (r= -0.36; p&lt;0.001). The mean left ventricular ejection fraction (LVEF) measured during echocardiography was 48.34±9.39%. Positive and significant correlation was found between LVEF and peripheral infiltration of intracoronary thrombus with neutrophils (r=0.37; p&lt;0.001), while negative correlation was found between LVEF and presence of microchannels within the clot (r= -0.27; p&lt;0.01). The mean total segmental left ventricular contractility index at the time of hospital discharge was 1.38 [1.25; 1.63]. This index negatively correlated with neutrophil infiltration (r= -0.37; p&lt;0.001), and positively – with the presence of microchannels in the obtained clot samples (r=0.26; p=0.01). Signs of left ventricular aneurysm formation before discharge from the hospital were found in 15 (15.46±3.67%) patients. A significant negative correlation was found between this parameter and the presence of peripheral neutrophil infiltration of intracoronary thrombi (r= -0.32; p&lt;0.01). The presence of peripheral infiltration of intracoronary thrombi with neutrophil leukocytes was associated with better left ventricular systolic function and less likely hood of development of left ventricular aneurysm or electrocardiographic QS pattern. The formation of microchannels within the clot was associated with poorer recovery of systolic cardiac function.