Marco Antonio Rodrigues Torres

Stress echo 2020: the international stress echo study in ischemic and non-ischemic heart disease

BackgroundStress echocardiography (SE) has an established role in evidence-based guidelines, but recently its breadth and variety of applications have extended well beyond coronary artery disease (CAD). We lack a prospective research study of SE applications, in and beyond CAD, also considering a variety of signs in addition to regional wall motion abnormalities.MethodsIn a prospective, multicenter, international, observational study design, > 100 certified high-volume SE labs (initially from Italy, Brazil, Hungary, and Serbia) will be networked with an organized system of clinical, laboratory and imaging data collection at the time of physical or pharmacological SE, with structured follow-up information. The study is endorsed by the Italian Society of Cardiovascular Echography and organized in 10 subprojects focusing on: contractile reserve for prediction of cardiac resynchronization or medical therapy response; stress B-lines in heart failure; hypertrophic cardiomyopathy; heart failure with preserved ejection fraction; mitral regurgitation after either transcatheter or surgical aortic valve replacement; outdoor SE in extreme physiology; right ventricular contractile reserve in repaired Tetralogy of Fallot; suspected or initial pulmonary arterial hypertension; coronary flow velocity, left ventricular elastance reserve and B-lines in known or suspected CAD; identification of subclinical familial disease in genotype-positive, phenotype- negative healthy relatives of inherited disease (such as hypertrophic cardiomyopathy).ResultsWe expect to recruit about 10,000 patients over a 5-year period (2016-2020), with sample sizes ranging from 5,000 for coronary flow velocity/ left ventricular elastance/ B-lines in CAD to around 250 for hypertrophic cardiomyopathy or repaired Tetralogy of Fallot. This data-base will allow to investigate technical questions such as feasibility and reproducibility of various SE parameters and to assess their prognostic value in different clinical scenarios.ConclusionsThe study will create the cultural, informatic and scientific infrastructure connecting high-volume, accredited SE labs, sharing common criteria of indication, execution, reporting and image storage of SE to obtain original safety, feasibility, and outcome data in evidence-poor diagnostic fields, also outside the established core application of SE in CAD based on regional wall motion abnormalities. The study will standardize procedures, validate emerging signs, and integrate the new information with established knowledge, helping to build a next-generation SE lab without inner walls.

A extensão universitária na FAMED/UFRGS : cenário de formação profissional

This study aimed to develop and apply are search methodology allowing the analysis of extension activities by faculty members from the School of Medicine of the Federal University in Rio Grande do Sul, Brazil, from 2000 to 2004. This qualitative research used a case study approach and content analysis of interviews and documents, besides mapping the activities in relation to the course plan, the relationship between the university and society, and the schools academic output. The results reveal the extension activities practiced by faculty members participating in the study during this period as a space for interaction between faculty, students, and the community in scenarios involving the production and construction of knowledge, contributing to the training of physicians committed to the social reality, as recommended by health curriculum guidelines and specifically those for medicine. The proposed methodology helped shed light on scenarios in which the extension activities take place, as well as on the interaction between extension, undergraduate and graduate studies, and research.

Avaliação diagnóstica da cardiomiopatia hipertrófica em fase clínica e pré-clínica

Hypertrophic cardiomyopathy is a familial, genetic disease caused by mutations in genes encoding sarcomeric proteins. It is characterized by various deGrees of left ventricular hypertrophy, usually diffuse, predominantly involving the interventricular septum. The asymptomatic forms with mild or no segmental hypertrophy makes it difficult to establish the diagnosis and screening for familial forms. Its high penetrance is often incomplete and, as a result, 20% to 30% of adults who carry disease-causing gene mutations do not express the phenotype. The susceptibility to sudden death and likelihood of late expression makes establishing a preclinical diagnosis all the more important. The use of Doppler echocardiography and magnetic resonance imaging, in conjunction with a detailed ECG analysis, may be useful in this process. Molecular genetic studies can identify mutations in 60% to 80% of the cases. However, its complex, time-consuming and costly nature, coupled with an inadequate assessment of genotype-phenotype relationships, limits its routine application. Major advances in imaging methods and the introduction of more simplified molecular techniques may contribute to clinical and preclinical diagnosis of hypertrophic cardiomyopathy, in addition to allowing implementation of therapeutic strategies to prevent or delay the development of the disease.

Ventricular arrhythmias and left ventricular hypertrophy in hypertrophic cardiomyopathy

BACKGROUND In hypertrophic cardiomyopathy (HCM), the degree of left ventricular hypertrophy (LVH) could influence the development of ventricular arrhythmias. OBJECTIVE In HCM, analyze the association between the occurrence of ventricular arrhythmias determined by Holter electrocardiogram (ECG-Holter) and the degree of LVH determined by maximum wall thickness (MWT) in echocardiography and body mass index (BMI). METHODS Fifty-four consecutive patients with HCM underwent 24-hour ECG-Holter and echocardiography for assessment of level of LVH through MWT and BMI. Two levels were established for the occurrence of Ventricular Arrhythmias: I - alone or paired extrasystoles and II - Non- Sustained Ventricular Tachycardia (NSVT). RESULTS In 13 patients (24%) with NSVT (level II), there was a higher frequency of MWT of the left ventricle (LV) > 21 mm (n = 10, 77%, 25 ± 4 mm) and LLLV = 144 g/m² (n = 10, 77%, 200 ± 30 g/m²), in comparison with those presenting with extrasystole arrhythmias (level I) (n = 41, 76%), in which these measures were identified in, respectively, 37 % (n= 15, 23 ± 1 mm), p = 0.023, and 39% (n = 16, 192 ± 53 g / m²) of the cases (p = 0.026). The cut-off values mentioned were determined by the ROC curve with a confidence interval of 95%. NSVT was more common in patients with MWTLV > 21 mm and LLLV > 144 g/m² (8 of 13, 62%) than in those with (4 of 13, 31%) or without (1 of 13; 8%) echocardiographic variables above cut-off values (p = 0.04). CONCLUSION In HCM, occurrence of ventricular arrhythmias by Holter was associated with the degree of LVH assessed by echocardiography through MWT and BMI.

O diagnóstico da obstrução da via de saída do ventrículo esquerdo na cardiomiopatia hipertrófica

Hypertrophic cardiomyopathy is a prevalent genetic disease characterized by left ventricular hypertrophy, presenting dynamic obstruction of outflow tract with subaortic gradient happening at rest in 30% of the cases. It is attributed to the intricate interaction between the anterior mitral leaflet, the interventricular septum and altered flow vectors generated in left ventricle along with changes in outflow tract geometry. Mitral regurgitation in varying degrees is found with or without association with structural deformities of the valve apparatus. The exercise echocardiogram evidences latent obstruction easily induced by exercise in 60 to 75% of non-obstructive forms. The determination of the gradient under this condition must be considered in routine investigation of patients with mild or no obstruction at rest. The evaluation of hypertrophic cardiomyopathy incorporates methods based on the ultrasound image, which, along with MRI, allow recognizing ventricular obstruction generating mechanisms, thus facilitating the diagnosis and management of obstructive and latent obstructive forms.

Left Ventricular Diastolic Function in Hemodialysis Patients: Role of Preload Increase Maneuver on Tissue Doppler Imaging Evaluation

Objective: Tissue Doppler imaging (TDI) has recently been proposed as a relatively preload-independent method to evaluate left ventricular diastolic function. We sought to investigate the higher-accuracy of TDI to assess diastolic function in end-stage renal disease (ESRD) patients on hemodialysis (HD) associated with a preload increase maneuver. Methods: Thirty-two consecutiveESRD patients (16 female, ages 48.8 ± 17.5 years, 14 ≤45 and 18 >45 years old) were evaluated. Measurements of E, A velocities and the E/A ratio from transmitral inflow pulsed wave Doppler, and E’, A’ velocities and the E’/A’ ratio from TDI were obtained 1 h before and 1 h after HD at baseline and with a preload increase maneuver. Results: The E/A ratio changed significantly in all patients aged >45 before and after HD with the preload increase maneuver. The E’/A’ ratio increased in all subjects with the preload increase maneuver before HD but did not change with the maneuver after HD in the euvolemic state in all patients. Conclusion: In ESRD patients on routine HD, TDI evaluation associated with a preload increase maneuver proved to be a more accurate method to identify diastolic dysfunction when the evaluation is performed in euvolemic patients after HD.

Prevalence and Phenotypic Expression of Mutations in the MYH7, MYBPC3 and TNNT2 Genes in Families with Hypertrophic Cardiomyopathy in the South of Brazil: A Cross-Sectional Study

Background: Mutations in sarcomeric genes are found in 60-70% of individuals with familial forms of hypertrophic cardiomyopathy (HCM). However, this estimate refers to northern hemisphere populations. The molecular-genetic profile of HCM has been subject of few investigations in Brazil, particularly in the south of the country. Objective: To investigate mutations in the sarcomeric genes MYH7, MYBPC3 and TNNT2 in a cohort of HCM patients living in the extreme south of Brazil, and to evaluate genotype-phenotype associations. Methods: Direct DNA sequencing of all encoding regions of three sarcomeric genes was conducted in 43 consecutive individuals of ten unrelated families. Results: Mutations for CMH have been found in 25 (58%) patients of seven (70%) of the ten study families. Fourteen (56%) individuals were phenotype-positive. All mutations were missense, four (66%) in MYH7 and two (33%) in MYBPC3. We have not found mutations in the TNNT2 gene. Mutations in MYH7 were identified in 20 (47%) patients of six (60%) families. Two of them had not been previously described. Mutations in MYBPC3 were found in seven (16%) members of two (20%) families. Two (5%) patients showed double heterozygosis for both genes. The mutations affected different domains of encoded proteins and led to variable phenotypic expression. A family history of HCM was identified in all genotype-positive individuals. Conclusions: In this first genetic-molecular analysis carried out in the south of Brazil, we found mutations in the sarcomeric genes MYH7 and MYBPC3 in 58% of individuals. MYH7-related disease was identified in the majority of cases with mutation.

Ergospirometry and Echocardiography in Early Stage of Heart Failure with Preserved Ejection Fraction and in Healthy Individuals

Background Heart failure with preserved ejection fraction is a syndrome characterized by changes in diastolic function; it is more prevalent among the elderly, women, and individuals with systemic hypertension (SH) and diabetes mellitus. However, in its early stages, there are no signs of congestion and it is identified in tests by adverse remodeling, decreased exercise capacity and diastolic dysfunction. Objective To compare doppler, echocardiographic (Echo), and cardiopulmonary exercise test (CPET) variables - ergospirometry variables - between two population samples: one of individuals in the early stage of this syndrome, and the other of healthy individuals. Methods Twenty eight outpatients diagnosed with heart failure according to Framingham’s criteria, ejection fraction > 50% and diastolic dysfunction according to the european society of cardiology (ESC), and 24 healthy individuals underwent Echo and CPET. Results The group of patients showed indexed atrial volume and left ventricular mass as well as E/E’ and ILAV/A´ ratios significantly higher, in addition to a significant reduction in peak oxygen consumption and increased VE/VCO2 slope, even having similar left ventricular sizes in comparison to those of the sample of healthy individuals. Conclusion There are significant differences between the structural and functional variables analyzed by Echo and CPET when comparing two population samples: one of patients in the early stage of heart failure with ejection fraction greater than or equal to 50% and another of healthy individuals.