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Objective: The aim of this study was to evaluate the effects of aging on metabolic, cardiovascular, autonomic, inflammatory, and oxidative stress parameters after ovarian hormone deprivation (OVX). Methods: Female Wistar rats (3 or 22 months old) were divided into: young controls, young ovariectomized, old controls, and old ovariectomized (bilateral ovaries removal). After a 9-week follow-up, physical capacity, metabolic parameters, and morphometric and cardiac functions were assessed. Subsequently, arterial pressure was recorded and cardiac autonomic control was evaluated. Oxidative stress was measured on the cardiac tissue, while inflammatory profile was assessed in the plasma. Results: Aging or OVX caused an increase in body and fat weight and triglyceride concentration and a decrease in both insulin sensitivity and aerobic exercise capacity. Left ventricular diastolic dysfunction and increased cardiac overload (myocardial performance index) were reported in old groups when compared with young groups. Aging and OVX led to an increased sympathetic tonus, and vagal tonus was lower only for the old groups. Tumor necrosis factor-α and interleukin-6 were increased in old groups when compared with young groups. Glutathione redox balance (GSH/GSSG) was reduced in young ovariectomized, old controls, and old ovariectomized groups when compared with young controls, indicating an increased oxidative stress. A negative correlation was found between GSH/GSSG and tumor necrosis factor-α (r=-0.6, P,0.003). Correlations were found between interleukin-6 with adipose tissue (r<0.5, P,0.009) and vagal tonus (r=-0.7, P,0.0002); and among myocardial performance index with interleukin-6 (r<0.65, P,0.0002), sympathetic tonus (r<0.55, P,0.006), and physical capacity (r=-0.55, P,0.003). The findings in this trial showed that ovariectomy aggravated the impairment of cardiac and functional effects of aging in female rats, probably associated with exacerbated autonomic dysfunction, inflammation, and oxidative stress. [ABSTRACT FROM AUTHOR]

Background: Blood donor screening leads to large numbers of new diagnoses of Trypanosoma cruzi infection, with most donors in the asymptomatic chronic indeterminate form. Information on electrocardiogram (ECG) findings in infected blood donors is lacking and may help in counseling and recognizing those with more severe disease. Objectives: To assess the frequency of ECG abnormalities in T.cruzi seropositive relative to seronegative blood donors, and to recognize ECG abnormalities associated with left ventricular dysfunction. Methods: The study retrospectively enrolled 499 seropositive blood donors in São Paulo and Montes Claros, Brazil, and 483 seronegative control donors matched by site, gender, age, and year of blood donation. All subjects underwent a health clinical evaluation, ECG, and echocardiogram (Echo). ECG and Echo were reviewed blindly by centralized reading centers. Left ventricular (LV) dysfunction was defined as LV ejection fraction (EF)<0.50%. Results: Right bundle branch block and left anterior fascicular block, isolated or in association, were more frequently found in seropositive cases (p<0.0001). Both QRS and QTc duration were associated with LVEF values (correlation coefficients −0.159,p<0.0003, and −0.142,p = 0.002) and showed a moderate accuracy in the detection of reduced LVEF (area under the ROC curve: 0.778 and 0.790, both p<0.0001). Several ECG abnormalities were more commonly found in seropositive donors with depressed LVEF, including rhythm disorders (frequent supraventricular ectopic beats, atrial fibrillation or flutter and pacemaker), intraventricular blocks (right bundle branch block and left anterior fascicular block) and ischemic abnormalities (possible old myocardial infarction and major and minor ST abnormalities). ECG was sensitive (92%) for recognition of seropositive donors with depressed LVEF and had a high negative predictive value (99%) for ruling out LV dysfunction. Conclusions: ECG abnormalities are more frequent in seropositive than in seronegative blood donors. Several ECG abnormalities may help the recognition of seropositive cases with reduced LVEF who warrant careful follow-up and treatment. Author Summary: Chagas disease (ChD), caused by the protozoa Trypanosoma cruzi, is endemic in most Latin America countries and may be transmitted via blood transfusions. Cardiac disease is a major feature of chronically infected patients and may be lethal. Universal blood bank screening for ChD has been established in most Latin American countries, as well as in non-endemic countries with large immigrant populations, including the United States, Canada, Spain and Portugal. Blood donor screening leads to large numbers of new diagnoses of chronic T. cruzi infection. Counseling these individuals should address the recognition of those with more severe disease that deserve to be rigorously evaluated by experienced cardiologists and treated more promptly. The electrocardiogram is an important exam that can help in the recognition of cardiac disease and the evaluation of prognosis in ChD patients, but its role in blood donors has not been studied. The authors describe some electrocardiographic abnormalities that are typical of the infected blood donors, as well ECG abnormalities that help in the identification of those with severe cardiac involvement. These results may guide the evaluations of patients with incidentally detected T. cruzi infection from blood bank testing or public health screening. [ABSTRACT FROM AUTHOR]

We investigated the impact of obesity on the abnormalities of systolic and diastolic regional left ventricular (LV) function in patients with or without hypertension or hypertrophy, and without heart failure. We studied 120 individuals divided into 6 groups of 20 patients (42 ± 6 years, 60 females) using standard and pulsed-wave tissue Doppler imaging (TDI) echocardiography, and heterogeneity index (HI): nonobese (I: no hypertension, no hypertrophy, control group; II: hypertension, no hypertrophy; III: hypertension and hypertrophy) and obese (IV: no hypertension, no hypertrophy; V: hypertension, no hypertrophy; VI: hypertension and hypertrophy). The criterion for obesity was BMI ≥30 kg/m2, for hypertension was blood pressure ≥140/90 mm Hg, for hypertrophy in nonobese was LV mass/body surface area (BSA) >134 g/m2 (men) and >110 mg/m2 (women), and in obese was LV mass/height(2.7) >50 (men) and >40 (women). Obese groups had normal LV ejection fraction compared with nonobese groups, but decreased longitudinal and radial systolic myocardial peak velocities (S′), and early diastolic myocardial peak velocity (E′). Also, a great variability of E′ and late diastolic myocardial peak velocity (A′) from the longitudinal basal region was observed in obese groups (E′basal nonobese: 11 ± 7 vs. obese 19 ± 11, P < 0.001, A′basal nonobese: 7 ± 4 vs. obese 11 ± 7, P < 0.001). Our findings were more evident when comparing groups IV with V and VI, with the latter having concentric hypertrophy and obvious segmental systolic and diastolic dysfunctions. Subclinical myocardial alterations and increased variability of the velocities were observed in obese groups, especially with hypertension and hypertrophy, reflecting impaired regional LV relaxation, segmental atrial, and systolic dysfunctions. [ABSTRACT FROM AUTHOR]

The article discusses a study on the role of late gadolinium enhancement (LGE)-cardiovascular magnetic resonance (CMR) in the diagnosis and prognosis of endomyocardial fibrosis (EMF). It indicates that LGE-CMR allows an assessment of the presence of myocardial inflammation fibrosis and injury acquired by a relative accumulation of gadolinium. It suggests that LGE-CMR is useful in diagnosing EMF by characterizations of fibrotic tissue (FT) distribution and that parameters evaluated by CMR can provide prognostic information.

Background: Changes in the proteoglycans glypican and syndecan-4 have been reported in several pathological conditions, but little is known about their expression in the heart during diabetes. The aim of this study was to investigate in vivo heart function changes and alterations in mRNA expression and protein levels of glypican-1 and syndecan-4 in cardiac and skeletal muscles during streptozotocin (STZ)-induced diabetes. Methods: Diabetes was induced in male Wistar rats by STZ administration. The rats were assigned to one of the following groups: control (sham injection), after 24 hours, 10 days, or 30 days of STZ administration. Echocardiography was performed in the control and STZ 10-day groups. Western and Northern blots were used to quantify protein and mRNA levels in all groups. Immunohistochemistry was performed in the control and 30-day groups to correlate the observed mRNA changes to the protein expression. Results: In vivo cardiac functional analysis performed using echocardiography in the 10-day group showed diastolic dysfunction with alterations in the peak velocity of early (E) diastolic filling and isovolumic relaxation time (IVRT) indices. These functional alterations observed in the STZ 10-day group correlated with the concomitant increase in syndecan-4 and glypican-1 protein expression. Cardiac glypican-1 mRNA and skeletal syndecan-4 mRNA and protein levels increased in the STZ 30-day group. On the other hand, the amount of glypican in skeletal muscle was lower than that in the control group. The same results were obtained from immunohistochemistry analysis. Conclusion: Our data suggest that membrane proteoglycans participate in the sequence of events triggered by diabetes and inflicted on cardiac and skeletal muscles. [ABSTRACT FROM AUTHOR]

Myocardial hypertrophy is the hallmark of chronic pressure overload and the myocardial performance index (MPI) is an easily recordable measurement of Doppler time intervals. In this study, the utility of using MPI to assess the progression of hypertrophy in the aortic-banded rat model was evaluated. Male Wistar rats (70–90 g) underwent ascending aorta constriction ( n = 4) or a sham operation ( n = 5). High-resolution echocardiography was performed 4, 7, 10, and 12 weeks after the surgery. Over this follow-up interval, animals in the aortic-banded group demonstrated an increase in their mean left ventricular (LV) mass and MPI compared with controls. MPI reflects ventricular performance in small animals with LV hypertrophy, showing alterations early after aorta constriction. [ABSTRACT FROM AUTHOR]

Endomyocardial fibrosis is manifested mainly by diastolic heart failure. However, diastolic function has not been well characterized in this disease. The aim of this study was to characterize left ventricular (LV) diastolic function in endomyocardial fibrosis (EMF) by echocardiography. Eighteen patients with LV EMF and 18 healthy subjects were studied. Cardiac volumes and ejection fraction were assessed by Simpson's method. Pulsed-wave Doppler was used to obtain mitral and pulmonary venous flow velocities and grade diastolic function. Pulsed-wave tissue Doppler imaging velocities along the septal side of mitral annulus, flow propagation velocity ( Vp) of the early diastolic mitral inflow, and myocardial performance index were obtained. According to this grading method, four patients with normal diastolic function, five with impaired relaxation, five with pseudonormal, and four with a restrictive pattern were found. A positive correlation of these diastolic function grades and NYHA functional class was found ( r = 0.66, P = 0.003). By “stepwise” logistic regression the best index that discriminated EMF patients from controls was Vp. The probability of occurrence of EMF = exp(7.9288 − 0.1366 Vp)/1 + exp(7.9288 − 0.1366 Vp). A wide range of diastolic function grades is found in patients with EMF and these correlated with functional class. Delayed myocardium relaxation, as reflected by altered Vp, was a frequent finding, making Vp the most useful index to discriminate EMF patients. [ABSTRACT FROM AUTHOR]

Previous studies show that COVID-19 survivors have elevated muscle sympathetic nerve activity (MSNA), endothelial dysfunction, and aortic stiffening. However, the neurovascular responses to mental stress and exercise are still unexplored. We hypothesized that COVID-19 survivors, compared with age- and body mass index (BMI)-matched control subjects, exhibit abnormal neurovascular responses to mental stress and physical exercise. Fifteen severe COVID-19 survivors (aged: 49 ± 2 yr, BMI: 30 ± 1 kg/m 2 ) and 15 well-matched control subjects (aged: 46 ± 3 yr, BMI: 29 ± 1 kg/m 2 ) were studied. MSNA (microneurography), forearm blood flow (FBF), and forearm vascular conductance (FVC, venous occlusion plethysmography), mean arterial pressure (MAP, Finometer), and heart rate (HR, ECG) were measured during a 3-min mental stress (Stroop Color-Word Test) and during a 3-min isometric handgrip exercise (30% of maximal voluntary contraction). During mental stress, MSNA (frequency and incidence) responses were higher in COVID-19 survivors than in controls ( P < 0.001), and FBF and FVC responses were attenuated ( P < 0.05). MAP was similar between the groups ( P > 0.05). In contrast, the MSNA (frequency and incidence) and FBF and FVC responses to handgrip exercise were similar between the groups ( P > 0.05). MAP was lower in COVID-19 survivors ( P < 0.05). COVID-19 survivors exhibit an exaggerated MSNA and blunted vasodilatory response to mental challenge compared with healthy adults. However, the neurovascular response to handgrip exercise is preserved in COVID-19 survivors. Overall, the abnormal neurovascular control in response to mental stress suggests that COVID-19 survivors may have an increased risk to cardiovascular events during mental challenge.

Background: COVID-19 has become a dramatic health problem during this century. In addition to high mortality rate, COVID-19 survivors are at increased risk for cardiovascular diseases 1-year after infection. Explanations for these manifestations are still unclear but can involve a constellation of biological alterations. We hypothesized that COVID-19 survivors compared with controls exhibit sympathetic overdrive, vascular dysfunction, cardiac morpho-functional changes, impaired exercise capacity, and increased oxidative stress., Methods: Nineteen severe COVID-19 survivors and 19 well-matched controls completed the study. Muscle sympathetic nerve activity (microneurography), brachial artery flow-mediated dilation and blood flow (Doppler-Ultrasound), carotid-femoral pulse wave velocity (Complior), cardiac morpho-functional parameters (echocardiography), peak oxygen uptake (cardiopulmonary exercise testing), and oxidative stress were measured ~3 months after hospital discharge. Complementary experiments were conducted on human umbilical vein endothelial cells cultured with plasma samples from subjects., Results: Muscle sympathetic nerve activity and carotid-femoral pulse wave velocity were greater and brachial artery flow-mediated dilation, brachial artery blood flow, E/e' ratio, and peak oxygen uptake were lower in COVID-19 survivors than in controls. COVID-19 survivors had lower circulating antioxidant markers compared with controls, but there were no differences in plasma-treated human umbilical vein endothelial cells nitric oxide production and reactive oxygen species bioactivity. Diminished peak oxygen uptake was associated with sympathetic overdrive, vascular dysfunction, and reduced diastolic function in COVID-19 survivors., Conclusions: Our study revealed that COVID-19 survivors have sympathetic overactivation, vascular dysfunction, cardiac morpho-functional changes, and reduced exercise capacity. These findings indicate the need for further investigation to determine whether these manifestations are persistent longer-term and their impact on the cardiovascular health of COVID-19 survivors.

Background: There are few contemporary cohorts of Trypanosoma cruzi -seropositive individuals, and the basic clinical epidemiology of Chagas disease is poorly understood. Herein, we report the incidence of cardiomyopathy and death associated with T. cruzi seropositivity., Methods: Participants were selected in blood banks at 2 Brazilian centers. Cases were defined as T. cruzi -seropositive blood donors. T. cruzi -seronegative controls were matched for age, sex, and period of donation. Patients with established Chagas cardiomyopathy were recruited from a tertiary outpatient service. Participants underwent medical examination, blood collection, ECG, and echocardiogram at enrollment (2008-2010) and at follow-up (2018-2019). The primary outcomes were all-cause mortality and development of cardiomyopathy, defined as the presence of a left ventricular ejection fraction <50% or QRS complex duration ≥120 ms, or both. To handle loss to follow-up, a sensitivity analysis was performed using inverse probability weights for selection., Results: We enrolled 499 T. cruzi -seropositive donors (age 48±10 years, 52% male), 488 T. cruzi -seronegative donors (age 49±10 years, 49% male), and 101 patients with established Chagas cardiomyopathy (age 48±8 years, 59% male). The mortality in patients with established cardiomyopathy was 80.9 deaths/1000 person-years (py) (54/101, 53%) and 15.1 deaths/1000 py (17/114, 15%) in T. cruzi -seropositive donors with cardiomyopathy at baseline. Among T. cruzi -seropositive donors without cardiomyopathy at baseline, mortality was 3.7 events/1000 py (15/385, 4%), which was no different from T. cruzi -seronegative donors with 3.6 deaths/1000 py (17/488, 3%). The incidence of cardiomyopathy in T. cruzi -seropositive donors was 13.8 (95% CI, 9.5-19.6) events/1000 py (32/262, 12%) compared with 4.6 (95% CI, 2.3-8.3) events/1000 py (11/277, 4%) in seronegative controls, with an absolute incidence difference associated with T. cruzi seropositivity of 9.2 (95% CI, 3.6-15.0) events/1000 py. T. cruzi antibody level at baseline was associated with development of cardiomyopathy (adjusted odds ratio, 1.4 [95% CI, 1.1-1.8])., Conclusions: We present a comprehensive description of the natural history of T. cruzi seropositivity in a contemporary patient population. The results highlight the central importance of anti- T. cruzi antibody titer as a marker of Chagas disease activity and risk of progression.

Objectives: To evaluate the effects of sympathectomy on the myocardium in an experimental model., Methods: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached., Results: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (p<0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09)., Conclusion: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity.

Aims: From pathophysiological mechanisms to risk stratification and management, much debate and discussion persist regarding left ventricular non-compaction cardiomyopathy (LVNC). This study aimed to characterize myocardial T1 mapping and extracellular volume (ECV) fraction by cardiovascular magnetic resonance (CMR), and investigate how these biomarkers relate to left ventricular ejection fraction (LVEF) and ventricular arrhythmias (VA) in LVNC., Methods and Results: Patients with LVNC (n = 36) and healthy controls (n = 18) were enrolled to perform a CMR with T1 mapping. ECV was quantified in LV segments without late gadolinium enhancement (LGE) areas to investigate diffuse myocardial fibrosis. Patients with LVNC had slightly higher native T1 (1024 ± 43 ms vs. 995 ± 22 ms, P = 0.01) and substantially expanded ECV (28.0 ± 4.5% vs. 23.5 ± 2.2%, P < 0.001) compared to controls. The ECV was independently associated with LVEF (β = -1.3, P = 0.001). Among patients without LGE, VAs were associated with higher ECV (27.7% with VA vs. 25.8% without VA, P = 0.002)., Conclusion: In LVNC, tissue characterization by T1 mapping suggests an extracellular expansion by diffuse fibrosis in myocardium without LGE, which was associated with myocardial dysfunction and VA, but not with the amount of non-compacted myocardium.

Aims: Autonomic dysfunction determines the advance of dilated cardiomyopathy (DCM) and is related to poor outcomes. However, this autonomic imbalance is unknown in patients with restrictive cardiomyopathy (RCM) even though they have similar symptoms and poor quality of life as DCM patients have. The aim of this study was to evaluate if autonomic and neurovascular controls were altered in RCM patients., Methods and Results: Fifteen RCM patients, 10 DCM patients, and 10 healthy subjects were evaluated. Heart rate and blood pressure (BP) were recorded. Peripheral sympathetic activity [muscle sympathetic nerve activity (MSNA)] by microneurography and cardiac sympathetic activity by power spectrum analysis of heart rate variability. Spontaneous baroreflex sensitivity (BRS) was evaluated by the sequence method and forearm blood flow by venous occlusion plethysmography. Both cardiomyopathy groups had higher MSNA frequency (P < 0.001) and MSNA incidence (P < 0.001), higher cardiac sympathovagal balance (P < 0.02), reduced BRS for increase (P = 0.002) and for decrease in BP (P = 0.002), and lower forearm blood flow (P < 0.001) compared with healthy subjects. We found an inverse correlation between BRS for increase and decrease in BP and peripheral sympathetic activity (r = -0.609, P = 0.001 and r = -0.648, P < 0.001, respectively) and between BRS for increase and decrease in BP and cardiac sympathetic activity (r = -0.503, P = 0.03 and r = -0.487, P = 0.04, respectively)., Conclusions: The RCM patients had cardiac and peripheral autonomic dysfunctions associated with peripheral vasoconstriction. Nonetheless, the presence of normal ejection fraction underestimates the evolution of the disease and makes clinical treatment difficult. These alterations could lead to a similar cardiovascular risk as that observed in DCM patients., (© 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.)

Background: Hypertrophic cardiomyopathy (HCM) is a common genetic disease that may cause left ventricular outflow tract (LVOT) obstruction, heart failure, and sudden death. Recent studies have shown a high prevalence of OSA among patients with HCM. Because the hemodynamics in patients with LVOT obstruction are unstable and depend on the loading conditions of the heart, we evaluated the acute effects of CPAP on hemodynamics and cardiac performance in patients with HCM., Methods: We studied 26 stable patients with HCM divided into nonobstructive HCM (n = 12) and obstructive HCM (n = 14) groups (LVOT gradient pressure lower or higher than 30 mm Hg, respectively). Patients in the supine position while awake were continuously monitored with beat-to-beat BP measurements and electrocardiography. Two-dimensional echocardiography was performed at rest (baseline) and after 20 min of nasal CPAP at 1.5 cm H 2 O and 10 cm H 2 O, which was applied in a random order interposed by 10 min without CPAP., Results: BP, cardiac output, stroke volume, heart rate, left ventricular ejection fraction, and LVOT gradient did not change during the study period in either group. CPAP at 10 cm H 2 O decreased right atrial size and right ventricular relaxation in all patients. It also decreased left atrial volume significantly and decreased right ventricular outflow acceleration time, suggesting an increase in pulmonary artery pressure in patients with obstructive HCM., Conclusions: The acute application of CPAP is apparently safe in patients with HCM, because CPAP does not lead to hemodynamic compromise. Long-term studies in patients with HCM and sleep apnea and nocturnal CPAP are warranted., Trial Registry: ClinicalTrials.gov; No. NCT01631006; URL: www.clinicaltrials.gov., (Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

A previously healthy 16-year-old woman experienced progressive dyspnea on exertion. The echocardiogram and cardiac magnetic resonance imaging showed a significant increase in cardiac chambers, severe biventricular systolic dysfunction, and prominent ventricular trabeculations suggesting noncompaction cardiomyopathy (NCC). The patient underwent heart transplantation 5 years after the NCC diagnosis, and the anatomopathological examination evidenced diffuse biventricular hypertrabeculation compromise, including the basal region of the biventricular wall. There is no consensus about the gold-standard diagnostic criteria, which demands a conceptual review and attention to another point: the relation of trabeculation volume and prognosis., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Aims: Endomyocardial fibrosis (EMF) is a restrictive cardiomyopathy manifested mainly by diastolic heart failure. It is recognized that diastole is an important determinant of exercise capacity. The purpose of this study was to determine whether resting echocardiographic parameters might predict oxygen consumption (VO(2p)) by ergoespirometry and the prognostic role of functional capacity in EMF patients., Methods and Results: A total of 32 patients with biventricular EMF (29 women, 55.3 +/- 11.4 years) were studied by echocardiography and ergoespirometry. The relationship between the echocardiographic indexes and the percentage of predicted VO(2p) (%VO(2p)) was investigated by the 'stepwise' linear regression analysis. The median VO(2p) was 11 +/- 3 mL/kg/min and the %VO(2p) was 53 +/- 9%. There was a correlation of %VO(2p) with an average of A' at four sites of the mitral annulus (A' peak, r = 0.471, P = 0.023), E'/A' of the inferior mitral annulus (r = -0.433, P = 0.044), and myocardial performance index (r = -0.352, P = 0.048). On multiple regression analysis, only A' peak was an independent predictor of %VO(2p) (%VO(2p)= 26.34 + 332.44 x A' peak). EMF patients with %VO(2p)< 53% had an increased mortality rate with a relative risk of 8.47., Conclusion: In EMF patients, diastolic function plays an important role in determining the limitations to exercise and %VO(2p) has a prognostic value.

Introduction: Chagas' disease is one of the most important causes of dilated cardiomyopathy in South and Central America. It is an inflammatory cardiomyopathy. We wanted to investigate whether it could have the same response to aldosterone antagonism as demonstrated before in other dilated cardiomyopathies., Objective: To evaluate the role of spironolactone in myocardial remodelling in a Chagas cardiomyopathy model., Material and Methods: We studied 60 Sirius Hamsters divided into: control (C) infected (Inf) and Inf plus spironolactone (Infsp, 40 mg/kg/day) groups, for 11 months. Echocardiography with colour doppler was performed. Left ventricular end diastolic diameter (LVEDD), fractional shortening (FS) and corrected isovolumic relaxation time (IRT) were evaluated, as well as interstitial collagen volume fraction (ICVF) and myocardial inflammation., Result: The results demonstrated that survival was improved by use of spironolactone in the chronic phase (p<0.04). Body weight (BW) was C:190 g, Inf:167 g*, Infsp:198 g (*p<0.05, compared to C and Infsp), LVEDD/BW was C:0.31, Inf: 0.35*, Infsp: 0.29 (*p<0.05, compared to C and Infsp), FS was C:38, Inf: 35.5, Infsp: 38 (with no statistical difference) and IRT was C: 23 msec, Inf: 26 msec*, Infsp: 22 msec (p<0.05, compared to C and Infsp). ICVF (%) was attenuated at LV (C: 0.34+/-0.1, Inf: 1.75+/-0.7*, Infsp: 0.95+/-0.2*; *p<0.05, p<0.05)., Conclusion: Spironolactone attenuated the myocardial remodelling in Chagas cardiomyopathy, reduced mortality during the chronic phase and reduced inflammatory infiltration.

Isolated noncompaction of the myocardium (INCM) is a rare, congenital, unclassified cardiomyopathy. It is caused by a disorder in endomyocardial morphogenesis in the absence of other structural disease. INCM is characterized by numerous prominent trabeculations and deep intertrabecular recesses in the myocardium. Frequently, INCM is associated with an increased incidence of heart failure, arrhythmias, and cardioembolic events with high morbidity and mortality. We describe a 28-year-old woman experiencing symptoms of heart failure since she was 4 years old. She had been intensively investigated and misdiagnosed as having dilated, restrictive, and apical hypertrophic cardiomyopathies. Cardiac magnetic resonance and echocardiography recently revealed the actual diagnosis of INCM. The patient is alive and well, taking vasodilators and warfarin. Herein, we describe the long-term follow-up of this patient and demonstrate that some patients have a favorable prognosis. In addition, the improvement in noninvasive cardiac imaging has revealed a higher prevalence of INCM, previously undetected.

Objective: To determine whether NT pro-BNP levels are high in patients reporting pericardial diseases, as well as to investigate how they relate to diastolic dysfunction echocardiographic measures., Methods: Twenty-five patients were split into two groups: 1) pericardial effusion (PE): 15 patients; 2) constrictive pericarditis (CP): 10 patients. A control group was made up with 30 individuals reporting no heart disease. Pericardial effusion was evaluated by bidimensional echocardiogram, with restriction evaluated by pulsed Doppler of mitral flow. CP diagnosis was confirmed by MRI. NT pro-BNP levels were measured by immunoassay and detected by electrochemiluminescence., Results: From the 15 PD patients, 14 reported relevant PD, and only 1, moderate PD. Log NT pro-BNP was shown to be higher in PD (p < 0.05), with log mean of 2.31 pg/ml and CP (p < 0.05), with log mean of 2.67 pg/ml, when compared to control group, log mean of 1.32 pg/ml. No difference was reported between PD and CP (p = 0.149). The NT pro-BNP log showed to be correlated to peak velocity of the E wave (r = 0.845; p = 0.001) and with E/A (r = 0.717; p = 0.003)., Conclusion: NT pro-BNP is shown to have increased in pericardial diseases, and is associated to diastolic dysfunction. It may serve as an additional method in quantifying restriction.

Aims: Echocardiography has recently been introduced to small animal research, allowing serial measurements of cardiac diseases. In addition, the hamster model has been increasingly used, as it mimics many human heart conditions. However, no reference range of echocardiographic values reflecting normal left ventricular (LV) function exists for hamsters. The purpose of this study was to provide one., Methods and Results: The study group consisted of 118 10-week-old, female, Syrian golden hamsters, which underwent high-resolution echocardiography. LV mass was calculated using the corrected cube formula, and LV systolic and diastolic function were assessed by fractional shortening and mitral inflow pulsed-wave Doppler, respectively. The myocardial performance index (MPI) measured the time spent in isovolumic activity and reflected both systolic and diastolic function. The mean+/-SD LV mass, fractional shortening, and MPI were 0.19+/-0.04 g, 44.7+/-6.6%, and 0.39+/-0.1, respectively. E and A waves were differentiated in 52% of all animals. Logistic regression adjusted with a cutoff of 378 bpm revealed that the risk of E/A wave fusion was 35 times greater (95% CI: 12.6; 98.4) in animals with a heart rate >378 bpm., Conclusion: This study documents echocardiographic characteristics in normal Syrian hamsters, which can be used as control values for future studies.

Chronic Chagas' disease cardiomyopathy (CCC) is caused by the protozoan Trypanosoma cruzi, and it affects 30% of the 16-18 million people infected in Latin America. A good rodent model that develops a dilated cardiomyopathy closely resembling human CCC after T. cruzi infection is still needed. We compared the cardiomyopathy developed by T. cruzi-infected Syrian hamsters with human Chagas' disease cardiomyopathy using quantitative methods. Female hamsters were infected with 3.5 x 10(4) (G1, n = 10) or 10(5) (G2, n = 10) T. cruzi Y strain blood trypomastigotes. Control animals (C, n = 10) were injected with saline solution. Cardiac function was assessed by echocardiography at 4, 8 and 12 months post-infection. Heart sections were submitted to histopathological/morphometric analysis 12 months post-infection. At this time, ventricular dysfunction and diffuse or multi-focal myocarditis were observed in 91% and 100% of G1 and G2 infected groups, respectively. Median interstitial collagen volumes in groups C, G1 and G2 were 1.2%, 1.9% and 3.9%, respectively, and were significantly higher in group G2 than in group C. Among infected animals, myocarditis showed a positive correlation with interstitial fibrosis. Deaths in the chronic phase (8-12 months post-infection) were more frequent among G2 than G1, and were associated with macroscopic ventricular dilation, severe myocarditis and increased fibrosis values, along with an earlier onset of ventricular dysfunction. The T. cruzi chronically infected Syrian hamster develops a cardiomyopathy which resembles human Chagas' disease cardiomyopathy, and might be an adequate tool to investigate pathogenic mechanisms of this disease and to search for novel therapeutic strategies.

We sought to noninvasively evaluate left ventricular (LV) function after cardiac hypertrophy induced by experimental stenosis of the ascending aorta. Male Wistar rats (70-90 g) underwent ascending aorta constriction by the surgical placement of a titanium clip (n=5) or sham operation (n=6). High-resolution bidimensional, pulsed-wave Doppler (PWD) and pulsed-wave tissue Doppler imaging (TDI) were performed 22 weeks after surgery. PWD was used to obtain mitral flow velocities, and TDI was used to obtain velocities along the septal mitral annulus and LV posterior wall. Clip placement produced myocardial hypertrophy with decreased systolic myocardial peak velocity in both the long and short axes. Increased myocardial mass, that is, posterior wall and septal thickness, was indicative of ventricular remodeling. Diastolic dysfunction was observed, with an increased early to late ratio of mitral velocities and increased left atrium dimension, consistent with a left ventricular restrictive filling pattern.