Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS. In LVEF, mitral E wave deceleration time < 160 ms and pulmonary S-wave < D-wave are also parameters of increased filling pressure. This algorithm does not apply to patients with atrial fibrillation (AF), mitral annulus calcification, > mild mitral valve disease, left bundle branch block, paced rhythm, prosthetic valves, or severe primary pulmonary hypertension.

Morphological and functional cardiac alterations in children with congenital Zika syndrome and severe neurological deficits

INTRODUCTION

Zika virus infection during pregnancy causes fetal microcephaly and brain damage. Congenital Zika syndrome (CZS) is characterized by systemic involvement with diffuse muscle impairment, a high frequency of arthrogryposis, and microphthalmia. Cardiac impairment in CZS has rarely been evaluated. Our study assessed morphology and biventricular cardiac function in children with CZS and advanced neurological dysfunction.

METHODS

This cross-sectional study was conducted on 52 children with CZS (Zika group; ZG) and 25 healthy children (control group; CG) in Paraiba, Brazil. Clinical evaluation, electrocardiogram (EKG), and transthoracic echocardiogram (TTE) were performed on all children. Additionally, troponin I and natriuretic peptide type B (BNP) levels, the degree of cerebral palsy, and neuroimaging findings were assessed in the ZG group.

RESULTS

The median age of the study population was 5 years in both groups, and 40.4% (ZG) and 60% (CG) were female. The most prevalent electrocardiographic alteration was sinus arrhythmia in both the ZG (n = 9, 17.3%) and CG (n = 4, 16%). The morphological parameters adjusted for Z score were as follows: left ventricular (LV) end-diastolic diameter in ZG: -2.36 [-5.10, 2.63] vs. CG: -1.07 [-3.43, 0.61], p<0.001); ascending aorta (ZG: -0.09 [-2.08, 1.60] vs. CG: 0.43 [-1.47, 2.2], p = 0.021); basal diameter of the right ventricle (RV) (ZG: -2.34 [-4.90, 0.97] vs. CG: -0.96 [-2.21, 0.40], p<0.01); and pulmonary artery dimension (ZG: -2.13 [-5.99, 0.98] vs. CG: -0.24 [-2.53, 0.59], p<0.01). The ejection fractions (%) were 65.7 and 65.6 in the ZG and CG, respectively (p = 0.968). The left atrium volume indices (mL/m2) in the ZG and CG were 13.15 [6.80, 18.00] and 18.80 [5.90, 25.30] (p<0.01), respectively, and the right atrium volume indices (mL/m2) were 10.10 [4.90, 15.30] and 15.80 [4.10, 24.80] (p<0.01). The functional findings adjusted for Z score were as follows: lateral systolic excursion of the mitral annular plane (MAPSE) (ZG: 0.36 [-2.79, 4.71] vs. CG: 1.79 [-0.93, 4.5], p = 0.001); tricuspid annular plane systolic excursion (TAPSE) (ZG: -2.43 [-5.47, 5.09] vs. CG: 0.07 [-1.98, 3.64], p<0.001); and the S' of the RV (ZG: 1.20 [3.35, 2.90] vs. CG: -0.20 [-2.15, 1.50], p = 0.0121). No differences in biventricular strain measurements were observed between the groups. Troponin I and BNP levels were normal in in the ZG. Grade V cerebral palsy and subcortical calcification were found in 88.6% and 97.22% of children in the ZG group, respectively.

CONCLUSION

A reduction in cardiac dimensions and functional changes were found in CZS patients, based on the TAPSE, S' of the RV, and MAPSE, suggesting the importance of cardiac evaluation and follow-up in this group of patients.

Endomyocardial fibrosis of the right ventricle in a patient with schistosomiasis: a case report

Background

Endomyocardial fibrosis (EMF) is a rare and underdiagnosed cause of restrictive cardiomyopathy. Its aetiology is not yet defined and could be caused by the influence of different clinical factors that seem to combine with genetic aspects of individuals susceptible to an inflammatory process that leads to formation of fibrosis.

Case summary

We describe a case of a 50-year-old man from the northeastern region of Brazil, where there is high prevalence of schistosomiasis. He presented to our centre with symptoms of right heart failure. The echocardiogram showed normal left ventricular ejection fraction. Right ventricular had normal systolic function but in the apical region was filled with a homogeneous and hypoechoic image causing obliteration and restriction of the apex. The late gadolinium enhancement with cardiac magnetic resonance showed diffuse and heterogeneous subendocardial fibrosis in the right ventricle apex consistent with EMF, but declined endocardiectomy.

Discussion

This report presents an interesting case of EMF and schistosomiasis simultaneously. The hypothesis of parasitosis as a probable cause of EMF was raised by helminth-induced hypereosinophilia. Complementary imaging tests such as magnetic resonance imaging and echocardiography, in addition to clinical and epidemiological suspicion, are essential for its diagnosis. Early surgical resolution becomes crucial for long-term survival.

A machine learning framework for the evaluation of myocardial rotation in patients with noncompaction cardiomyopathy

Aims

Noncompaction cardiomyopathy (NCC) is considered a genetic cardiomyopathy with unknown pathophysiological mechanisms. We propose to evaluate echocardiographic predictors for rigid body rotation (RBR) in NCC using a machine learning (ML) based model.

Methods and results

Forty-nine outpatients with NCC diagnosis by echocardiography and magnetic resonance imaging (21 men, 42.8±14.8 years) were included. A comprehensive echocardiogram was performed. The layer-specific strain was analyzed from the apical two-, three, four-chamber views, short axis, and focused right ventricle views using 2D echocardiography (2DE) software. RBR was present in 44.9% of patients, and this group presented increased LV mass indexed (118±43.4 vs. 94.1±27.1g/m², P = 0.034), LV end-diastolic and end-systolic volumes (P< 0.001), E/e’ (12.2±8.68 vs. 7.69±3.13, P = 0.034), and decreased LV ejection fraction (40.7±8.71 vs. 58.9±8.76%, P < 0.001) when compared to patients without RBR. Also, patients with RBR presented a significant decrease of global longitudinal, radial, and circumferential strain. When ML model based on a random forest algorithm and a neural network model was applied, it found that twist, NC/C, torsion, LV ejection fraction, and diastolic dysfunction are the strongest predictors to RBR with accuracy, sensitivity, specificity, area under the curve of 0.93, 0.99, 0.80, and 0.88, respectively.

Conclusion

In this study, a random forest algorithm was capable of selecting the best echocardiographic predictors to RBR pattern in NCC patients, which was consistent with worse systolic, diastolic, and myocardium deformation indices. Prospective studies are warranted to evaluate the role of this tool for NCC risk stratification.

THE INFLUENCE OF ISCHEMIC PRECONDITIONING ON NEUROMUSCULAR PERFORMANCE

ABSTRACT Introduction: Ischemic preconditioning (IPC) has been described in the literature as a resource capable of improving physical performance. Objective: The purpose of this randomized double-blind study was to evaluate the influence of IPC on the neuromuscular performance of trained individuals. Methods: Twenty-four (24) resistance training participants (6 of them women) with a mean age of 25.8 ± 4.6 years were selected and divided into two groups: the upper limb group (ULG) composed of 12 individuals (4 women) and the lower limb group (LLG) composed of 12 individuals (2 women). The maximum repetitions test was applied in the bench press for the ULG and in the 45° leg press for the LLG, with 50% of the one-repetition maximum under control, placebo and IPC conditions, at a random interval of 72 hours between tests. The IPC was applied four hours before the tests by means of an analog sphygmomanometer cuff inflated to 220 mmHg on the arm for the ULG and on the thigh for LLG, with three cycles of five minutes each of ischemia and reperfusion, alternating between the right and left sides. For the placebo, the cuff was inflated to 40 mmHg without causing ischemia. The significance level for the Wilcoxon test was p <0.017, due to the Bonferroni correction. The effect size (ES) was also analyzed. Results: With IPC, the ULG performed 34.8 ± 4.8 repetitions, representing an improvement of 11.29% (IPC vs. control, ES = 0.68 and p = 0.002) and the LLG performed 40.5 ± 15.7 repetitions, representing an improvement of 37.47% (IPC vs. control, ES = 0.84 and p = 0.002). No significant improvements were observed for the placebo in either group. Conclusion: Our data showed that IPC positively influenced neuromuscular performance of both the upper and lower limbs. Level of evidence II; Therapeutic studies investigating the results of treatment (Prospectived comparative studye).

Reduction in Hospitalization and Increase in Mortality Due to Cardiovascular Diseases during the COVID-19 Pandemic in Brazil

BACKGROUND

In the COVID-19 pandemic, the increase in the incidence of cardiovascular diseases (CVD) and mortality from them has been recognized worldwide. In Brazil, the impact of COVID-19 on CVD must be evaluated.

OBJECTIVES

To assess the impact of the current pandemic on the numbers of hospital admissions (HA), in-hospital deaths (ID), and in-hospital fatality (IF) from CVD by use of national epidemiological data from the Brazilian Unified Public Health System.

METHODS

Time-series observational study using comparative analysis of the HA, ID, and IF due to CVD recorded from January to May 2020, having as reference the values registered in the same period from 2016 to 2019 and the values projected by linear regression methods for 2020. The statistical significance level applied was 0.05.

RESULTS

Compared to the same period in 2019, there was a 15% decrease in the HA rate and a 9% decrease in the total ID due to CVD between March and May 2020, followed by a 9% increase in the IF rate due to CVD, especially among patients aged 20-59 years. The HA and IF rates registered in 2020 differed significantly from the projected trend for 2020 (p = 0.0005 and 0.0318, respectively).

CONCLUSIONS

During the first months of the pandemic, there were a decline in HA and an increase in IF due to CVD in Brazil. These data might have resulted from the inadequate planning of the CVD management during the pandemic. Thus, immediate actions are required to change this scenario. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0).

Worsening of heart failure by coronavirus disease 2019 is associated with high mortality

AIMS

Patients with advanced heart failure (HF) with reduced left ventricular ejection fraction (HFrEF) and concurrent coronavirus disease 2019 (COVID-19) might have a higher risk of severe events.

METHODS AND RESULTS

We retrospectively studied 16 patients with advanced HFrEF who developed COVID-19 between 1 March and 29 May 2020. Follow-up lasted until 30 September. Ten patients previously hospitalized with decompensated HFrEF were infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during hospitalization. Six patients undergoing ambulatory care at initiation of COVID-19 symptoms were hospitalized because of advanced HFrEF. All patients who experienced worsening of HFrEF due to COVID-19 required higher doses or introduction of additional inotropic drugs or intra-aortic balloon pump in the intensive care unit. The mean intravenous dobutamine dose before SARS-CoV-2 infection in previously hospitalized patients (n = 10) and the median (inter-quartile range) peak intravenous dobutamine dose during SARS-CoV-2 infection in all patients (n = 16) were 2 (0-7) μg/kg/min and 20 (14-20) (P < 0.001), respectively. During follow-up, 56% underwent heart transplantation (n = 2) or died (n = 7). Four patients died during hospitalization from mixed shock consequent to severe acute respiratory syndrome with inflammatory storm syndrome associated with septic and cardiogenic shock during COVID-19. After COVID-19 recovery, two patients died from mixed septic and cardiogenic shock and one from sustained ventricular tachycardia and cardiogenic shock. Five patients were discharged from hospital to ambulatory care. Four were awaiting heart transplantation.

CONCLUSION

Worsening of advanced HF by COVID-19 is associated with high mortality. This report highlights the importance of preventing COVID-19 in patients with advanced HF.

Pulmonary Hypertension in Obese Mice Is Accompanied by a Reduction in PPAR-γ Expression in Pulmonary Artery

Obesity and insulin resistance (IR) are well-studied risk factors for systemic cardiovascular disease, but their impact on pulmonary hypertension (PH) is not well clarified. This study aims to investigate if diet-induced obesity induces PH and if peroxisome-proliferator-activated receptor (PPAR-γ) and/or endoplasmic reticulum (ER) stress are involved in this process. Mice were maintained on a high-fat diet (HFD) for 4 months, and IR and PH were confirmed. In a separate group, after 4 months of HFD, mice were treated with pioglitazone (PIO) or 4-phenylbutyric acid for the last month. The results demonstrated that HFD for at least 4 months is able to increase pulmonary artery pressure, which is maintained, and this animal model can be used to investigate the link between IR and PH, without changes in ER stress in the pulmonary artery. There was also a reduction in circulating adiponectin and in perivascular adiponectin expression in the pulmonary artery, associated with a reduction in PPAR-γ expression. Treatment with PIO improved IR and PH and reversed the lower expression of adiponectin and PPAR-γ in the pulmonary artery, highlighting this drug as potential benefit for this poorly recognized complication of obesity.

Biventricular imaging markers to predict outcomes in non-compaction cardiomyopathy: a machine learning study

Aims

Left ventricular non‐compaction cardiomyopathy (LVNC) is a genetic heart disease, with heart failure, arrhythmias, and embolic events as main clinical manifestations. The goal of this study was to analyse a large set of echocardiographic (echo) and cardiac magnetic resonance imaging (CMRI) parameters using machine learning (ML) techniques to find imaging predictors of clinical outcomes in a long‐term follow‐up of LVNC patients.

Methods and results

Patients with echo and/or CMRI criteria of LVNC, followed from January 2011 to December 2017 in the heart failure section of a tertiary referral cardiologic hospital, were enrolled in a retrospective study. Two‐dimensional colour Doppler echocardiography and subsequent CMRI were carried out. Twenty‐four hour Holter monitoring was also performed in all patients. Death, cardiac transplantation, heart failure hospitalization, aborted sudden cardiac death, complex ventricular arrhythmias (sustained and non‐sustained ventricular tachycardia), and embolisms (i.e. stroke, pulmonary thromboembolism and/or peripheral arterial embolism) were registered and were referred to as major adverse cardiovascular events (MACEs) in this study. Recruited for the study were 108 LVNC patients, aged 38.3 ± 15.5 years, 48.1% men, diagnosed by echo and CMRI criteria. They were followed for 5.8 ± 3.9 years, and MACEs were registered. CMRI and echo parameters were analysed via a supervised ML methodology. Forty‐seven (43.5%) patients had at least one MACE. The best performance of imaging variables was achieved by combining four parameters: left ventricular (LV) ejection fraction (by CMRI), right ventricular (RV) end‐systolic volume (by CMRI), RV systolic dysfunction (by echo), and RV lower diameter (by CMRI) with accuracy, sensitivity, and specificity rates of 75.5%, 77%, 75%, respectively.

Conclusions

Our findings show the importance of biventricular assessment to detect the severity of this cardiomyopathy and to plan for early clinical intervention. In addition, this study shows that even patients with normal LV function and negative late gadolinium enhancement had MACE. ML is a promising tool for analysing a large set of parameters to stratify and predict prognosis in LVNC patients.

Use of sacubitril/valsartan in non‐compaction cardiomyopathy: a case report

The use of sacubitril/valsartan significantly reduces death or hospitalization in patients with ejection fraction < 40%. There is no study evaluating this drug effects in non‐compaction cardiomyopathy (NCCM) individuals.

The aim of this article is to report a case of a patient with NCCM initially refractory to gold standard treatment and afterwards treated with sacubitril/valsartan and its improvements. This is a case report of a 48‐year‐old woman, presenting with NCCM heart failure, who had received standard guideline‐directed medical therapy for 18 months without any improvement in clinical and echocardiographic parameters. After that period, sacubitril/valsartan was initiated. After 18 months of refractory usage of guideline‐directed medical therapy, sacubitril/valsartan was started, and significant change in functional class (III to I) and important ventricular remodelling were achieved with an improvement of 29% in the ejection fraction, reduction of 7 mm in ventricular diastolic diameter, and mild to none mitral valve functional regurgitation.

In this case report, sacubitril/valsartan use was associated with improvement of echocardiographic and clinical parameters in a patient with NCCM.

P2577Losartan diminishes the expression of TGF-beta and improves cardiomyopathy in mice with Marfan syndrome

Introduction

Marfan syndrome (MFS) is caused by mutations in the fibrillin-1 gene, leading to abnormal signaling of the transforming growth factor beta (TGF-β). This results in aortic root dilation, dissection and rupture, which are the main causes of morbidity and mortality of MFS patients. Current treatment with losartan, an angiotensin-II receptor-1 blocker, has shown beneficial effect on aortic disease in MFS murine models. However, the mechanisms whereby the treatment with losartan improves cardiac remodeling and function of the left ventricle (LV) in MFS are still unknown.

Purpose

To investigate the effects of losartan on mechanisms of the cardiomyopathy in mice with MFS.

Methods

mgΔloxPneo MFS murine model from C129/sv background was utilized in this study. To evaluate the effect of the treatment with losartan on the LV of MFS and wild-type mice, animals were allocated in 2 groups of treatments: Losartan group: mice were kept with water supplemented with losartan (0.6g/L); Untreated control group: mice were kept with water only. The animals received treatment from 1 month of age until completing 6 months. After five months of treatment, LV echocardiography was performed, and fragments of LV tissue were analyzed by morphometry and protein expression analysis by Western blot.

Results

Losartan MFS mice showed decrease in interventricular septum and posterior wall thickness and LV mass. Furthermore, losartan prevented aortic and mitral regurgitation, arrhythmia, bradycardia, septal hypokinesia and pulmonary hypertension when compared with control MFS mice. Systolic and diastolic LV function were not different between groups. Collagen volume fraction and the disorganization and disruptions of the elastic fibers in coronary arteries were lower in losartan treatment than in controls. The protein expression of pro-apoptotic factors (BAX/Bcl-2 and caspase 3 and 9), proliferating cell nuclear antigen and hypoxia-inducible factor 1 and 2α were lower in losartan treatment, whereas the expression of vascular endothelial growth factor was increased in losartan group when compared with control MFS mice. Moreover, the treatment with losartan strongly reduced the TGF-β, ERK and p38MAPK protein expression compared to controls.

Conclusion

In this murine model of MFS, losartan treatment has the ability to change several pathophysiological mechanisms related with the fibrillin-1 mutation, by decreasing apoptosis, cell proliferation and increasing angiogenesis. Overall, the treatment resulted in improved structural rearrangement and attenuation of the rupture of elastic fibers in the coronary arteries, of the cardiac hypertrophy and myocardial fibrosis. These effects were possibly related with the decreased TGF-β expression by ERK and p38MAPK signaling pathways by losartan. Our findings shed a new light on the mechanisms of action of losartan on MFS cardiomyopathy.

Acknowledgement/Funding

FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo)

P6295Methotrexate reduces cardiac remodeling and improves left ventricle function in rats with Takotsubo cardiomyopathy

Introduction

Takotsubo cardiomyopathy (TC) is characterized by cardiac disfunction and left ventricle (LV) remodeling caused, mainly, by physical or emotional stress. Previously, we have shown in atherosclerotic rabbits that methotrexate (MTX), an anti-inflammatory chemotherapeutic agent, is capable of reducing the inflammatory process and atherosclerotic lesions.

Purpose

To investigate the effect of MTX treatment in rats with TC.

Methods

TC was induced in Wistar rats with 2 injections of isoproterenol (85mg/kg) with a 24h interval. Animals were allocated in 3 experimental groups: CT: animals induced and treated with saline; TK: animal induced with isoproterenol and treated with saline; TK-MTX: animals induced with isoproterenol and treated with MTX (1mg/kg). Animals were treated every week for 4 weeks. After the treatment, echocardiography, morphometry and molecular analysis (Western blot) of the LV were performed.

Results

TK and TK-MTX groups did not show cardiac dilation or LV intraventricular septum and posterior wall thickening. However, compared to TK, the treatment with MTX improved both LV systolic and diastolic function. In addition, the treatment diminished myocytes diameter and subendocardial and interstitial fibrosis of the LV. Protein expression of pro-apoptotic factors (caspase 3 and BAX), pro-inflammatory cytokine TNF-α, metalloproteinase 2, transforming growth factor beta, collagen I and III and hypoxia-inducible factor 2 alfa were all decreased. Vascular endothelial growth factor (VEGF) and adenosine A1 receptor showed increased protein expression in TK-MTX group when compared to CT and TK. There was correlation of myocardial fibrosis (r2=-0.57), myocytes diameter (r2=-0.78) and VEGF expression (r2=0.58) with LV systolic disfunction. Also, myocardial fibrosis (r2=0.57) and VEGF expression (r2=-0.68) correlated with diastolic disfunction in the LV. Animals treated with MTX did not present any toxicity.

Conclusion

Treatment with MTX diminished apoptosis, the expression of TNF-α and metalloproteinases, cardiac hypertrophy and myocardial fibrosis. Besides that, the treatment increased angiogenesis and strongly improved cardiac function of the LV. MTX, possibly through an increase in the production of intracellular adenosine, could be considered as a feasible treatment for TC.

Acknowledgement/Funding

FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo)

P4681Early findings in patients with noncompaction cardiomyopathy and normal ejection fraction: a cardiopulmonary exercise test, echocardiographic and biomarkers study

Background

Noncompaction cardiomyopathy (NCC) is a cardiomyopathy with controversial diagnostic criteria. Furthermore, it has been discussed whether asymptomatic individuals with normal left ventricular (LV) ejection fraction (EF) and diagnostic criteria for this disease could be classified as NCC. Therefore, the objective of this study was to evaluate the functional capacity of patients with NCC and the relation with echocardiographic and biomarkers indices.

Methods

Fifty-nine patients with NCC were prospectively divided into three groups: ejection fraction (EF)>50% (G1), EF between 40 - 50% (G2) and EF <40% (G3). In addition, 11 normal healthy volunteers were selected for control group (CG). All subjects underwent 2D echocardiography with tissue Doppler and myocardial deformation indices, cardiopulmonary exercise test (CPET), troponin I and BNP measurements.

Results

There was a decrease in VO2 peak (ml/km/min) in all NCC groups compared to CG (GC= 34.5±5.3, G1= 25.56±5.6, G2= 25.12±7.7 and G3= 21.86±6.3 ml/kg/min, p<0.001), but no difference was shown among NCC patients (p=0.37). In addition, the VO2 at anaerobic threshold (AT) was lower in all NCC groups compared to CG (GC= 22.88±3.3, G1= 17.30±4.7, G2= 18.58±5.2, e G3= 15.65±3.7 ml/kg/min, p<0.001). There was an increase in indexed ventricular mass in all NCC groups when compared to CG (p<0.001), but it was similar among NCC groups (p=0.72). Regarding to diastolic function, G2 and G3 presented a reduction in the peak velocity of the septal E' when compared to the control group (GC= 14.0±2.4, G2= 8.92±3.0 e G3= 6.86±3.9 cm/s, p<0,001), while E/E' was increased in G3 compared to all groups (p<0.001). G2 and G3 presented a decrease in global longitudinal strain (GLS) when compared to CG and G1 (p<0.001). The BNP levels were higher in G3 compared to the other groups (p<0.05), but no difference was found in troponin I levels. There was a positive correlation between VO2 peak and E' (r=0.56, p<0.001) and a negative correlation between VO2 peak and E/E' (r=−0.53, p<0.001). In addition, there was an inverse correlation between VO2 peak and BNP (r=−0.50, p<0.001).

Conclusion

Our results show that NCC patients present alterations in functional capacity, echocardiographic indices and biomarkers values according to LV dysfunction. Moreover, patients with preserved LV function already present predominant alterations in CPET suggesting subclinical myocardial dysfunction. For this reason, clinical treatment could be considered in this initial stage of this disease.

P4553Clinical and prognostic value of right ventricular dysfunction in patients with chagas heart disease during acute decompensated heart failure

Introduction

The occurrence of right ventricular disfunction (RVD) is common in heart failure (HF) patients due to Chagas' disease (ChD). However, its clinical and prognostic value has not been studied during episodes of acute decompensated heart failure (ADHF).

Purpose

Evaluate the prognostic value of RVD in ADHF patients with ChD during hospitalization and after 180 days of discharge compared to other etiologies.

Methods

We analysed a prospective cohort of consecutive 768 patients admitted for ADHF between March 2013 and October 2018; 490 (63.7%) patients were male and the median age was 58 (48.3–66.8) years and left ventricular ejection fraction was 26% (median) (IQR 22–35%). We compared the clinical characteristics and the prognosis of ChD patients according to the presence of RVD in the echocardiogram to other etiologies.

Results

RVD was presented in 289 (37.6%) patients. Among patients with non-chagasic etiologies, those with RVD were younger [53 (41–62) vs 61 (52–70) years, p<0.0001], had high levels of BNP in the moment of hospitalization [1195 (606–2209) vs 886 (366– 555) pg/mL], p<0,0001], received more inotropes (79.2% vs 57.9%, p<0,0001), had longer hospitalization [35 (17–51) vs 21 (10–37) days, p<0.001] and more clinical signs of congestion as hepatomegaly (49% vs 28.6%, p<0.0001); jugular venous distension (68.3% vs 41.2%, p<0.0001) and leg edema (65.4% vs 49.2%, p=0.001). Among patients with ChD, those with RVD were older [61 (48- 66) vs 58 (48 - 67) years, p=0.017], and had more frequently signs of hypoperfusion (56.8% vs 36.5%, p=0.029), jugular venous distension (72.8% vs 52.8%, p=0.01) and hepatomegaly (56.8% vs 31.1%, p=0.011), higher BNP levels [1288 (567–2180) vs 1066 (472–2007) pg/mL, p=0.006] and more frequent use of intravenous inotropes (88.9% vs 67.1%, p=0.003); additionally ChD patients with RVD had a higher rate of death and transplant during hospitalization (51.2% vs 38.3%, p=0.001). When all groups were compared together, ChD patients with RVD had the highest rate of death, transplant and readmissions at 180-days of follow-up (Figure).

Figure 1

Conclusion

Patients with RVD demonstrated a distinct clinical presentation, biomarkers and worse prognosis in all etiologies. ChD patients with RVD in ADHF had the worst prognosis with the highest rate of death, heart transplant e rehospitalization in follow-up.

Prognosis and risk stratification in patients with decompensated heart failure receiving inotropic therapy

Objectives

The prognostic significance of transient use of inotropes has been sufficiently studied in recent heart failure (HF) populations. We hypothesised that risk stratification in these patients could contribute to patient selection for advanced therapies.

Methods

We analysed a prospective cohort of adult patients admitted with decompensated HF and ejection fraction (left ventricular ejection fraction (LVEF)) less than 50%. We explored the outcomes of patients requiring inotropic therapy during hospital admission and after discharge.

Results

The study included 737 patients, (64.0% male), with a median age of 58 years (IQR 48-66 years). Main aetiologies were dilated cardiomyopathy in 273 (37.0%) patients, ischaemic heart disease in 195 (26.5%) patients and Chagas disease in 163 (22.1%) patients. Median LVEF was 26 % (IQR 22%-35%). Inotropes were used in 518 (70.3%) patients. In 431 (83.2%) patients, a single inotrope was administered. Inotropic therapy was associated with higher risk of in-hospital death/urgent heart transplant (OR=10.628, 95% CI 5.055 to 22.344, p<0.001). At 180-day follow-up, of the 431 patients discharged home, 39 (9.0%) died, 21 (4.9%) underwent transplantation and 183 (42.4%) were readmitted. Inotropes were not associated with outcome (death, transplant and rehospitalisation) after discharge.

Conclusions

Inotropic drugs are still widely used in patients with advanced decompensated HF and are associated with a worse in-hospital prognosis. In contrast with previous results, intermittent use of inotropes during hospitalisation did not determine a worse prognosis at 180-day follow-up. These data may add to prognostic evaluation in patients with advanced HF in centres where mechanical circulatory support is not broadly available.

Combined aerobic and resistance exercise training attenuates cardiac dysfunctions in a model of diabetes and menopause

The study aimed at evaluating the effects of combined aerobic and resistance exercise training on cardiac morphometry and function, oxidative stress and inflammatory parameters in diabetic ovariectomized rats. For this, female Wistar rats (10 weeks-old) were divided into 4 groups (n = 8): euglycemic (E), diabetic (streptozotocin, 50 mg/kg, iv) (D), diabetic ovariectomized (DO) and trained diabetic ovariectomized (TDO). The combined exercise training was performed on a treadmill and in a ladder adapted to rats (8 weeks, at 40-60% of maximal capacity). The left ventricle (LV) morphometry and function were evaluated by echocardiography. Oxidative stress and inflammatory markers were measured on ventricles tissue. The sedentary diabetic animals (D and DO) showed impaired systolic and diastolic functions, as well as increased cardiac overload, evaluated by myocardial performance index (MPI- D: 0.32 ± 0.05; DO: 0.39 ± 0.13 vs. E: 0.25 ± 0.07), in relation to E group. Systolic and MPI dysfunctions were exacerbated in DO when compared to D group. The DO group presented higher protein oxidation and TNF-α/IL-10 ratio than D groups. Glutathione redox ratio (GSH/GSSG) and IL-10 were decreased in both D and DO groups when compared to E group. Exercise training improved exercise capacity, systolic and diastolic functions and MPI (0.18±0.11). The TDO group showed reduced protein oxidation and TNF-α/IL-10 ratio and increased GSH/GSSG and IL-10 in relation to the DO group. These results showed that combined exercise training was able to attenuate the cardiac dysfunctions, probably by reducing inflammation and oxidative stress in an experimental model of diabetes and menopause.

Clinical findings and prognosis of patients hospitalized for acute decompensated heart failure: Analysis of the influence of Chagas etiology and ventricular function

Aims

Explore the association between clinical findings and prognosis in patients with acute decompensated heart failure (ADHF) and analyze the influence of etiology on clinical presentation and prognosis.

Methods and results

Prospective cohort of 500 patients admitted with ADHF from Aug/2013-Feb/2016; patients were predominantly male (61.8%), median age was 58 (IQ_25-75% 47–66 years); etiology was dilated cardiomyopathy in 141 (28.2%), ischemic heart disease in 137 (27.4%), and Chagas heart disease in 113 (22.6%). Patients who died (154 [30.8%]) or underwent heart transplantation (53[10.6%]) were younger (56 years [IQ_25-75% 45–64 vs 60 years, IQ_25-75% 49–67], P = 0.032), more frequently admitted for cardiogenic shock (20.3% vs 6.8%, P<0.001), had longer duration of symptoms (14 days [IQ_25-75% 4–32.8 vs 7.5 days, IQ_25-75% 2–31], P = 0.004), had signs of congestion (90.8% vs 76.5%, P<0.001) and inadequate perfusion more frequently (45.9% vs 28%, P<0.001), and had lower blood pressure (90 [IQ_25-75% 80–100 vs 100, IQ_25-75% 90–120], P<0.001). In a logistic regression model analysis, systolic blood pressure (P<0.001, OR 0.97 [95%CI 0.96–0.98] per mmHg) and jugular distention (P = 0.004, OR 1.923 [95%CI 1.232–3.001]) were significant. Chagas patients were more frequently admitted for cardiogenic shock (15%) and syncope/arrhythmia (20.4%). Pulmonary congestion was rare among Chagas patients and blood pressure was lower. The rate of in-hospital death or heart transplant was higher among patients with Chagas (50.5%).

Conclusions

A physical exam may identify patients at higher risk in a contemporaneous population. Our findings support specific therapies targeted at Chagas patients in the setting of ADHF.

It is recognized that the clinical evaluation of patients remains the basis for the characterization of diseases, data interpretation, and patient care. However, incorporation of technological methods into clinical practice has challenged the way cardiologists’ value of history and clinical examination. The present study sought to analyze the importance of clinical findings in a contemporaneous cohort of patients admitted with decompensated heart failure. Our results indicate that the physical exam may identify patients at higher risk in a contemporaneous patient population, and that clinical presentation varies according to etiology—especially Chagas disease—and ventricular function. Our findings support the need of development of specific therapeutic approaches targeted at Chagas patients in the setting of acute decompensated heart failure, as they represent a more vulnerable population.

Erythropoietin reduces collagen deposition after myocardial infarction but does not improve cardiac function

Myocardial remodeling includes inappropriate collagen deposition in the interstitium. Erythropoietin (EPO) may have cardioprotective effects. We aimed to assess the role of EPO on myocardial remodeling during the chronic phase. We studied 60 Wistar rats divided into the following groups: control (CT), control + EPO (CT + EPO), myocardial infarction + EPO (MI + EPO), and myocardial infarction (MI). The interstitial collagen volume fraction (ICVF) was quantified and echocardiography was performed. We quantified asymmetric dimethylarginine and glutathione by ELISA, and used real-time PCR to assess apoptosis and inflammation. Western blotting was used to evaluate inflammatory proteins and tissue inhibitors of metalloproteinases (TIMPs), and TUNEL staining was used to detect apoptosis. For matrix metalloproteinases (MMPs), we performed zymography. Parametric and nonparametric analyses were performed according to normality testing. ICVF was greater in MI groups (p < 0.001) and was attenuated by EPO (p = 0.05). The MMP-2 did not show any difference between groups. The TIMP-1 and TIMP-2 did not have difference between groups. The MI groups had worse fraction shortening (p < 0.001), without EPO protection (p = 0.666). The MI groups had increased left ventricle diastolic dimension (p < 0.001) without EPO attenuation (p = 0.79). EPO did not act on oxidative stress. Apoptosis and inflammation were not modulated by EPO. We concluded that EPO attenuated interstitial collagen accumulation, but did not protect from heart dilation or dysfunction.

Vitamin C mitigates oxidative/nitrosative stress and inflammation in doxorubicin-induced cardiomyopathy

Increase in oxidative/nitrosative stress is one of the mechanisms associated with the development of cardiotoxicity due to doxorubicin (Dox), a potent chemotherapy drug. Previously, we reported mitigation of Dox-induced oxidative/nitrosative stress and apoptosis by vitamin C (Vit C) in isolated cardiomyocytes. In the present in vivo study in rats, we investigated the effect of prophylactic treatment with Vit C on Dox-induced apoptosis, inflammation, oxidative/nitrosative stress, cardiac dysfunction, and Vit C transporter proteins. Dox (cumulative dose: 15 mg/kg) in rats reduced systolic and diastolic cardiac function and caused structural damage. These changes were associated with a myocardial increase in reactive oxygen species, reduction in antioxidant enzyme activities, increased expression of apoptotic proteins, and inflammation. Dox also caused an increase in the expression of proapoptotic proteins Bax, Bnip-3, Bak, and caspase-3. An increase in oxidative/nitrosative stress attributable to Dox was indicated by an increase in superoxide, protein carbonyl formation, lipid peroxidation, nitric oxide (NO), NO synthase (NOS) activity, protein nitrosylation, and inducible NOS protein expression. Dox increased the levels of cardiac proinflammatory cytokines TNF-α, IL-1β, and IL-6, whereas the expression of Vit C transporter proteins (sodium-ascorbate cotransporter 2 and glucose transporter 4) was reduced. Prophylactic and concurrent treatment with Vit C prevented all these changes and improved survival in the Vit C + Dox group. Vit C also improved Dox-mediated systolic and diastolic dysfunctions and structural damage. These results suggest a cardioprotective role of Vit C in Dox-induced cardiomyopathy by reducing oxidative/nitrosative stress, inflammation, and apoptosis, as well as improving Vit C transporter proteins.NEW & NOTEWORTHY This in vivo study provides novel data that vitamin C improves cardiac structure and function in doxorubicin-induced cardiomyopathy by reducing oxidative/nitrosative stress, apoptosis, and inflammation along with upregulation of cardiac vitamin C transporter proteins. The latter may have a crucial role in improving antioxidant status in this cardiomyopathy.

Decreased glycolytic metabolism in non-compaction cardiomyopathy by 18F-fluoro-2-deoxyglucose positron emission tomography: new insights into pathophysiological mechanisms and clinical implications

Aims

The pathophysiological mechanisms of left ventricular non-compaction cardiomyopathy (LVNC) remain controversial. This study performed combined 18F-fluoro-2-deoxyglucose dynamic positron emission tomography (FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (SPECT) studies to evaluate myocardial glucose metabolism and perfusion in patients with LVNC and their clinical implications.

Methods and results

Thirty patients (41 ± 12 years, 53% male) with LVNC, diagnosed by cardiovascular magnetic resonance (CMR) criteria, and eight age-matched healthy controls (42 ± 12 years, 50% male) were prospectively recruited to undergo FDG-PET with measurement of the myocardial glucose uptake rate (MGU) and SPECT to investigate perfusion-metabolism patterns. Patients with LVNC had lower global MGU compared with that in controls (36.9 ± 8.8 vs. 44.6 ± 5.4 μmol/min/100 g, respectively, P = 0.02). Of 17 LV segments, MGU levels were significantly reduced in 8, and also a reduction was observed when compacted segments from LVNC were compared with the segments from control subjects (P < 0.001). Perfusion defects were also found in 15 (50%) patients (45 LV segments: 64.4% match, and 35.6% mismatch perfusion-metabolism pattern). Univariate and multivariate analyses showed that beta-blocker therapy was associated with increased MGU (beta coefficient = 10.1, P = 0.008). Moreover, a gradual increase occurred in MGU across the beta-blocker dose groups (P for trend = 0.01).

Conclusion

The reduction of MGU documented by FDG-PET in LVNC supports the hypothesis that a cellular metabolic pathway may play a role in the pathophysiology of LVNC. The beneficial effect of beta-blocker mediating myocardial metabolism in the clinical course of LVNC requires further investigation.

Dysregulation of Autonomic Nervous System in Chagas' Heart Disease Is Associated with Altered Adipocytokines Levels

BACKGROUND

Chagas disease (CD) induces autonomic dysfunction and inflammatory activity, which may promote metabolic abnormalities. We studied metabolism and his correlation with Autonomic Nervous System (ANS) and inflammation in CD.

METHODS AND RESULTS

Sixty subjects were divided into 4 groups: control group (CG), IF (indeterminate form) group; ECG group (ECG abnormalities and normal left ventricular systolic function), and LVD group (left ventricular sistolic dysfunction). Levels of adiponectin, leptin, insulin, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) were assayed in serum samples by ELISA. ANS was assessed by heart rate variability in frequency domain in 24-hour Holter and postural tilt test (rest and orthostatic position). High frequency (HFr) component values were used to estimate parasympathetic activity and low frequency (LFr) component, sympathetic activity. Analyzes were made of the correlations of each of the metabolic parameters (leptin and adiponectin) with the inflammatory cytokines (interleukin-6 and TNF- alpha) and with the ANS assessment measurements. No significant differences were observed in leptin and insulin levels. Adiponectin was higher in ECG and LVD groups: [CG = 4766.5 (5529.5), IF = 4003.5 (2482.5), ECG = 8376.5 (8388.5), LVD = 8798 (4188.0) ng/mL, p<0.001)]. IL-6 and TNF-alpha were higher in LVD group: [IL-6: CG = 1.85 (6.41); IF = 1.58 (1.91); ECG = 1.0 (1.57); LVD= 31.44 (72.19) pg/ml; p = 0.001. TNF-alpha: CG = 22.57 (88.2); IF = 19.31 (33.16); ECG = 12.45 (3.07); LVD = 75.15 (278.57) pg/ml; p = 0.04]. Adiponectin levels had a positive association with the HFr component (r = 0.539; p = 0.038) and an inverse association with the LFr component (r = - 0.539; p = 0.038) in ECG group. Leptin levels had a negative association with the HFr component (r= - 0.632; p = 0.011) and a positive association with the LFr component (r = 0.632; p = 0.011) in LVD group.

CONCLUSIONS

We found increased adiponectin levels in Chagas' heart disease with systolic dysfunction and in patients with ECG abnormalities and normal systolic function at rest. Adipocytokines levels (adiponectin and leptin) were associated with ANS parameters in Chagas' heart disease.

Noncompaction cardiomyopathy: a substrate for a thromboembolic event

Background

Noncompaction cardiomyopathy (NCC) is a rare genetic cardiomyopathy characterized by a thin, compacted epicardial layer and an extensive noncompacted endocardial layer. The clinical manifestations of this disease include ventricular arrhythmia, heart failure, and systemic thromboembolism.

Case presentation

A 43-year-old male was anticoagulated by pulmonary thromboembolism for 1 year when he developed progressive dyspnea. Cardiovascular magnetic resonance imaging showed severe biventricular trabeculation with an ejection fraction of 15%, ratio of maximum noncompacted/compacted diastolic myocardial thickness of 3.2 and the presence of exuberant biventricular apical thrombus.

Conclusion

Still under discussion is the issue of which patients and when they should be anticoagulated. It is generally recommended to those presenting ventricular systolic dysfunction, antecedent of systemic embolism, presence of cardiac thrombus and atrial fibrillation. In clinical practice the patients with NCC and ventricular dysfunction have been given oral anticoagulation, although there are no clinical trials showing the real safety and benefit of this treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2261-15-7) contains supplementary material, which is available to authorized users.

Differential effects of variation in athletes training on myocardial morphophysiological adaptation in men: focus on ¹²³I-MIBG assessed myocardial sympathetic activity

PURPOSE

High intensity systematic physical training leads to myocardial morphophysiological adaptations. The goal of this study was to investigate if differences in training were correlated with differences in cardiac sympathetic activity.

METHODS

58 males (19-47 years), were divided into three groups: strength group (SG), (20 bodybuilders), endurance group (EG), (20 endurance athletes), and a control group (CG) comprising 18 healthy non-athletes. Cardiac sympathetic innervation was assessed by planar myocardial (123)I-metaiodobenzylguanidine scintigraphy using the early and late heart to mediastinal (H/M) ratio, and washout rate (WR).

RESULTS

Left ventricular mass index was significantly higher both in SG (P < .001) and EG (P = .001) compared to CG without a statistical significant difference between SG and EG (P = .417). The relative wall thickness was significantly higher in SG compared to CG (P < .001). Both left ventricular ejection fraction and the peak filling rate showed no significant difference between the groups. Resting heart rate was significantly lower in EG compared to CG (P = .006) and SG (P = .002). The late H/M ratio in CG was significantly higher compared to the late H/M for SG (P = .003) and EG (P = .004). However, WR showed no difference between the groups. There was no significant correlation between the parameters of myocardial sympathetic innervation and parameters of left ventricular function.

CONCLUSIONS

Strength training resulted in a significant increase in cardiac dimensions. Both strength and endurance training seem to cause a reduction in myocardial sympathetic drive. However, myocardial morphological and functional adaptations to training were not correlated with myocardial sympathetic activity.

Effects of exercise training on circulating and skeletal muscle renin-angiotensin system in chronic heart failure rats

BACKGROUND

Accumulated evidence shows that the ACE-AngII-AT1 axis of the renin-angiotensin system (RAS) is markedly activated in chronic heart failure (CHF). Recent studies provide information that Angiotensin (Ang)-(1-7), a metabolite of AngII, counteracts the effects of AngII. However, this balance between AngII and Ang-(1-7) is still little understood in CHF. We investigated the effects of exercise training on circulating and skeletal muscle RAS in the ischemic model of CHF.

METHODS/MAIN RESULTS

Male Wistar rats underwent left coronary artery ligation or a Sham operation. They were divided into four groups: 1) Sedentary Sham (Sham-S), 2) exercise-trained Sham (Sham-Ex), sedentary CHF (CHF-S), and exercise-trained CHF (CHF-Ex). Angiotensin concentrations and ACE and ACE2 activity in the circulation and skeletal muscle (soleus and plantaris) were quantified. Skeletal muscle ACE and ACE2 protein expression, and AT1, AT2, and Mas receptor gene expression were also evaluated. CHF reduced ACE2 serum activity. Exercise training restored ACE2 and reduced ACE activity in CHF. Exercise training reduced plasma AngII concentration in both Sham and CHF rats and increased the Ang-(1-7)/AngII ratio in CHF rats. CHF and exercise training did not change skeletal muscle ACE and ACE2 activity and protein expression. CHF increased AngII levels in both soleus and plantaris muscle, and exercise training normalized them. Exercise training increased Ang-(1-7) in the plantaris muscle of CHF rats. The AT1 receptor was only increased in the soleus muscle of CHF rats, and exercise training normalized it. Exercise training increased the expression of the Mas receptor in the soleus muscle of both exercise-trained groups, and normalized it in plantaris muscle.

CONCLUSIONS

Exercise training causes a shift in RAS towards the Ang-(1-7)-Mas axis in skeletal muscle, which can be influenced by skeletal muscle metabolic characteristics. The changes in RAS circulation do not necessarily reflect the changes occurring in the RAS of skeletal muscle.

Exercise-induced decrease in myocardial high-energy phosphate metabolites in patients with Chagas heart disease

BACKGROUND

The influence of exercise on cardiac metabolic response in patients with Chagas disease is incompletely understood.

METHODS AND RESULTS

Changes in cardiac energetic metabolism were investigated in Chagas disease patients before and during isometric handgrip exercise with (31)P magnetic resonance spectroscopy (MRS). Twenty-eight patients (10 with systolic dysfunction: group I; 10 with normal systolic function and electrocardiogram (ECG) abnormalities: group II; and 8 asymptomatic without ECG abnormalities: group III) and 8 healthy control subjects (group C) were evaluated by electrocardiogram, echocardiogram, functional tests for coronary artery disease, and image-selected localized cardiac (31)P-MRS. The myocardial phosphocreatine to [β-phosphate]adenosine triphosphate ratio (PCr/β-ATP) was measured at rest and during isometric handgrip exercise. Exercise testing or 99mTc-sestamibi scintigraphy were negative for myocardial ischemia in all individuals. At rest, cardiac PCr/β-ATP was decreased in all Chagas groups (1.23 ± 0.37) versus group C (1.88 ± 0.08; P < .001) and was lower in group I (0.89 ± 0.24) versus groups II (1.44 ± 0.23) and III (1.40 ± 0.37; P < .001). There was no stress-induced change in cardiac PCr/β-ATP (1.88 ± 0.08 at rest vs 1.89 ± 0.08 during exercise; P = NS) in group C. Mean cardiac PCr/β-ATP was 0.89 ± 0.24 and 0.56 ± 0.21 at rest and during exercise, respectively, in group I (37% decrease; P < .001). In group II, PCr/β-ATP was 1.44 ± 0.23 at rest and 0.97 ± 0.37 during exercise (33% decrease; P < .001). In group III, PCr/β-ATP was 1.40 ± 0.37 at rest and 0.60 ± 0.19 during exercise (57% decrease; P < .001).

CONCLUSIONS

Myocardial high-energy phosphates are reduced at rest in Chagas heart disease patients, and the reduction is greater in patients with left ventricular dysfunction. Regardless of left ventricular function, Chagas patients exhibit an exercise-induced decline in cardiac high-energy phosphates consistent with myocardial ischemia, suggesting the possibility that this metabolic approach may offer a tool to probe new interventions in Chagas disease patients.

The effect of beta-blockade on myocardial remodelling in Chagas' cardiomyopathy

OBJECTIVE

Chagas' disease has spread throughout Latin America because of the high rate of migration among these countries. Approximately 30% of Chagas' patients will develop cardiomyopathy, and 10% of these will develop severe cardiac damage leading to heart failure. Beta-blockade improves symptoms and survival in heart failure patients; however, its efficacy has not been well established in Chagas' disease. We evaluated the role of carvedilol in cardiac remodeling and mortality in a Chagas' cardiomyopathy animal model.

METHODS

We studied Trypanosoma cruzi infection in 55 Syrian hamsters that were divided into three groups: control (15), infected (20), and infected + carvedilol (20). Animals underwent echocardiography, electrocardiography, and morphometry for collagen evaluation in ventricles stained with picrosirius red.

RESULTS

The left ventricular diastolic diameter did not change between groups, although it was slightly larger in infected groups, as was left ventricular systolic diameter. Fractional shortening also did not change between groups, although it was slightly lower in infected groups. Collagen accumulation in the interstitial myocardial space was significantly higher in infected groups and was not attenuated by carvedilol. The same response was observed in the perivascular space. The survival curve showed significantly better survival in the control group compared with the infected groups; but no benefit of carvedilol was observed during the study. However, in the acute phase (up to 100 days of infection), carvedilol did reduce mortality.

CONCLUSION

Carvedilol did not attenuate cardiac remodeling or mortality in this model of Chagas' cardiomyopathy. The treatment did improve survival in the acute phase of the disease.

Lack of β2-AR improves exercise capacity and skeletal muscle oxidative phenotype in mice

β(2)-adrenergic receptor (β(2)-AR) agonists have been used as ergogenics by athletes involved in training for strength and power in order to increase the muscle mass. Even though anabolic effects of β(2)-AR activation are highly recognized, less is known about the impact of β(2)-AR in endurance capacity. We presently used mice lacking β(2)-AR [β(2)-knockout (β(2) KO)] to investigate the role of β(2)-AR on exercise capacity and skeletal muscle metabolism and phenotype. β(2) KO mice and their wild-type controls (WT) were studied. Exercise tolerance, skeletal muscle fiber typing, capillary-to-fiber ratio, citrate synthase activity and glycogen content were evaluated. When compared with WT, β(2) KO mice displayed increased exercise capacity (61%) associated with higher percentage of oxidative fibers (21% and 129% of increase in soleus and plantaris muscles, respectively) and capillarity (31% and 20% of increase in soleus and plantaris muscles, respectively). In addition, β(2) KO mice presented increased skeletal muscle citrate synthase activity (10%) and succinate dehydrogenase staining. Likewise, glycogen content (53%) and periodic acid-Schiff staining (glycogen staining) were also increased in β(2) KO skeletal muscle. Altogether, these data provide evidence that disruption of β(2)-AR improves oxidative metabolism in skeletal muscle of β(2) KO mice and this is associated with increased exercise capacity.

Exercise training prevents diastolic dysfunction induced by metabolic syndrome in rats

OBJECTIVE

High fructose consumption contributes to the incidence of metabolic syndrome and, consequently, to cardiovascular outcomes. We investigated whether exercise training prevents high fructose diet-induced metabolic and cardiac morphofunctional alterations.

METHODS

Wistar rats receiving fructose overload (F) in drinking water (100 g/l) were concomitantly trained on a treadmill (FT) for 10 weeks or kept sedentary. These rats were compared with a control group (C). Obesity was evaluated by the Lee index, and glycemia and insulin tolerance tests constituted the metabolic evaluation. Blood pressure was measured directly (Windaq, 2 kHz), and echocardiography was performed to determine left ventricular morphology and function. Statistical significance was determined by one-way ANOVA, with significance set at p<0.05.

RESULTS

Fructose overload induced a metabolic syndrome state, as confirmed by insulin resistance (F: 3.6 ± 0.2 vs. C: 4.5 ± 0.2 mg/dl/min), hypertension (mean blood pressure, F: 118 ± 3 vs. C: 104 ± 4 mmHg) and obesity (F: 0.31 ± 0.001 vs. C: 0.29 ± 0.001 g/mm). Interestingly, fructose overload rats also exhibited diastolic dysfunction. Exercise training performed during the period of high fructose intake eliminated all of these derangements. The improvements in metabolic parameters were correlated with the maintenance of diastolic function.

CONCLUSION

The role of exercise training in the prevention of metabolic and hemodynamic parameter alterations is of great importance in decreasing the cardiac morbidity and mortality related to metabolic syndrome.

Cardiac and pulmonary arterial remodeling after sinoaortic denervation in normotensive rats

Blood pressure variability (BPV) and baroreflex dysfunction may contribute to end-organ damage process. We investigated the effects of baroreceptor deficit (10 weeks after sinoaortic denervation - SAD) on hemodynamic alterations, cardiac and pulmonary remodeling. Cardiac function and morphology of male Wistar intact rats (C) and SAD rats (SAD) (n=8/group) were assessed by echocardiography and collagen quantification. BP was directly recorded. Ventricular hypertrophy was quantified by the ratio of left ventricular weight (LVW) and right ventricular weight (RVW) to body weight (BW). BPV was quantified in the time and frequency domains. The atrial natriuretic peptide (ANP), alpha-skeletal actin (α-skelectal), collagen type I and type III genes mRNA expression were evaluated by RT-PCR. SAD did not change BP, but increased BPV (11±0.49 vs. 5±0.3 mmHg). As expected, baroreflex was reduced in SAD. Pulmonary artery acceleration time was reduced in SAD. In addition, SAD impaired diastolic function in both LV (6.8±0.26 vs. 5.02±0.21 mmHg) and RV (5.1±0.21 vs. 4.2±0.12 mmHg). SAD increased LVW/BW in 9% and RVW/BW in 20%, and augmented total collagen (3.8-fold in LV, 2.7-fold in RV, and 3.35-fold in pulmonary artery). Also, SAD increased type I (~6-fold) and III (~5-fold) collagen gene expression. Denervation increased ANP expression in LV (75%), in RV (74%) and increased α-skelectal expression in LV (300%) and in RV (546%). Baroreflex function impairment by SAD, despite not changing BP, induced important adjustments in cardiac structure and pulmonary hypertension. These changes may indicate that isolated baroreflex dysfunction can modulate target tissue damage.

Treatment of left main coronary artery lesion after late thoracic radiotherapy

Prevention of late cardiovascular complications after radiation therapy (RT) for treatment of a malignant tumor is challenging. We report the case of a young male patient with Hodgkin's lymphoma treated with RT, who developed ischemic heart disease during follow-up, although he had no cardiovascular risk factors. We conclude that patients undergoing RT who experience chest pain should be fully investigated for coronary artery disease.

Pulmonary hypertension diagnosed by right heart catheterisation in sickle cell disease

Recent studies have recognised the importance of pulmonary hypertension (PH) in sickle cell disease (SCD). The aim of this study was to determine the prevalence and prognostic impact of PH and its features in patients with SCD. 80 patients with SCD underwent baseline clinical evaluation, laboratory testing, 6-min walk tests (6MWTs) and echocardiography. Patients with a peak tricuspid regurgitant jet velocity (TRV) of ≥ 2.5 m·s(-1) were further evaluated through right heart catheterisation (RHC) to assure the diagnosis of PH. Our study evidenced a 40% prevalence of patients with elevated TRV at echocardiography. RHC (performed in 25 out of 32 patients) confirmed PH in 10% (95% CI 3.4-16.5%) of all patients, with a prevalence of post-capillary PH of 6.25% (95% CI 0.95-11.55%) and pre-capillary PH of 3.75% (95% CI -0.4-7.9%). Patients with PH were older, had worse performance in 6MWTs, and more pronounced anaemia, haemolysis and renal dysfunction. Survival was shorter in patients with PH. Our study reinforced the use of echocardiography as a screening tool for PH in SCD and the mandatory role of RHC for proper diagnosis. Our findings confirmed the prognostic significance of PH in SCD as its association to pronounced haemolytic profile.

An unusual association of endomyocardial fibrosis and hypertrophic cardiomyopathy in a patient with heart failure

A 69-year-old female patient presented heart failure with preserved ejection fraction and atrial fibrillation. Echocardiography and late gadolinium enhancement magnetic resonance imaging were suggestive of endomyocardial fibrosis (EMF). The patient underwent cardiac surgery, and after surgery, she developed low cardiac output syndrome and died. Postmortem examination revealed residual fibrosis of the left ventricle (LV), mild endocardial fibrous deposition of the right ventricle, and severe concentric, symmetrical LV hypertrophy. Histological examination of the surgically resected material from the LV confirmed EMF. Histopathology of the interventricular septum disclosed myocardial hypertrophy and disarray plus fine interstitial fibrosis, typical of hypertrophic cardiomyopathy. The present case illustrates the association of two different patterns of cardiomyopathies in the same patient.