Influence of Physical Training after a Myocardial Infarction on Left Ventricular Contraction Mechanics. / Influência do Exercício Físico sobre a Mecânica de Contração do Ventrículo Esquerdo após Infarto do Miocárdio.

BACKGROUND: Exercise plays a positive role in the course of the ischemic heart disease, enhancing functional capacity and preventing ventricular remodeling. OBJECTIVE: To investigate the impact of exercise on left ventricular (LV) contraction mechanics after an uncomplicated acute myocardial infarction (AMI). METHODS: A total of 53 patients was included, 27 of whom were randomized to a supervised training program (TRAINING group), and 26 to a CONTROL group, who received usual recommendations on physical exercise after AMI. All patients underwent cardiopulmonary stress testing and a speckle tracking echocardiography to measure several parameters of LV contraction mechanics at one month and five months after AMI. A p value < 0.05 was considered statistically significant for the comparisons of the variables. RESULTS: No significant difference were found in the analysis of LV longitudinal, radial and circumferential strain parameters between groups after the training period. After the training program, analysis of torsional mechanics demonstrated a reduction in the LV basal rotation in the TRAINING group in comparison to the CONTROL group (5.9±2.3 vs. 7.5±2.9o; p=0.03), and in the basal rotational velocity (53.6±18.4 vs.68.8±22.1 º/s; p=0.01), twist velocity (127.4±32.2 vs. 149.9±35.9 º/s; p=0.02) and torsion (2.4±0.4 vs. 2.8±0.8 º/cm; p=0.02). CONCLUSIONS: Physical activity did not cause a significant improvement in LV longitudinal, radial and circumferential deformation parameters. However, the exercise had a significant impact on the LV torsional mechanics, consisting of a reduction in basal rotation, twist velocity, torsion and torsional velocity which can be interpreted as a ventricular "torsion reserve" in this population.

FUNDAMENTO: O exercício exerce um papel positivo na evolução da doença cardíaca isquêmica, melhorando a capacidade funcional e prevenindo o remodelamento ventricular. OBJETIVO: Investigar o impacto do exercício sobre a mecânica de contração do ventrículo esquerdo (VE) após um infarto agudo do miocárdio (IAM) não complicado. MÉTODOS: Um total de 53 pacientes foram incluídos e alocados aleatoriamente em um programa de treinamento supervisionado (grupo TREINO, n=27) ou em um grupo CONTROLE (n=26) que recebeu recomendações usuais sobre a prática de exercício físico após um IAM. Todos os pacientes realizaram um teste cardiopulmonar e um ecocardiograma com speckle tracking para medir vários parâmetros da mecânica de contração do VE em um mês e cinco meses após o IAM. Um valor de p <0,05 foi considerado para significância estatística nas comparações das variáveis. RESULTADOS: Não foram encontradas diferenças nas análises dos parâmetros de strain circunferencial, radial ou longitudinal do VE entre os grupos após o período de treinamento. Após o programa, a análise da mecânica de torção revelou uma redução na rotação basal do VE no grupo TREINO em comparação ao grupo CONTROLE (5,9±2,3 vs. 7,5±2.9o; p=0,03), bem como na velocidade rotacional basal (53,6±18,4 vs. 68,8± 22,1 º/s; p=0,01), velocidade de twist (127,4±32,2 vs. 149,9±35,9 º/s; p=0,02) e na torção (2,4±0,4 vs. 2,8±0, º/cm; p=0,02). CONCLUSÕES: A atividade física não causou melhora significativa nos parâmetros de deformação longitudinal, radial ou circunferencial do VE. No entanto, o exercício teve um impacto significativo sobre a mecânica de torção do VE, que consistiu em uma redução na rotação basal, na velocidade de twist, na torção, e na velocidade de torção, que pode ser interpretada como uma "reserva" de torção ventricular nessa população.

Influência do Exercício Físico sobre a Mecânica de Contração do Ventrículo Esquerdo após Infarto do Miocárdio / Influence of Physical Training after a Myocardial Infarction on Left Ventricular Contraction Mechanics

Resumo Fundamento O exercício exerce um papel positivo na evolução da doença cardíaca isquêmica, melhorando a capacidade funcional e prevenindo o remodelamento ventricular. Objetivo Investigar o impacto do exercício sobre a mecânica de contração do ventrículo esquerdo (VE) após um infarto agudo do miocárdio (IAM) não complicado. Métodos Um total de 53 pacientes foram incluídos e alocados aleatoriamente em um programa de treinamento supervisionado (grupo TREINO, n=27) ou em um grupo CONTROLE (n=26) que recebeu recomendações usuais sobre a prática de exercício físico após um IAM. Todos os pacientes realizaram um teste cardiopulmonar e um ecocardiograma com speckle tracking para medir vários parâmetros da mecânica de contração do VE em um mês e cinco meses após o IAM. Um valor de p <0,05 foi considerado para significância estatística nas comparações das variáveis. Resultados Não foram encontradas diferenças nas análises dos parâmetros de strain circunferencial, radial ou longitudinal do VE entre os grupos após o período de treinamento. Após o programa, a análise da mecânica de torção revelou uma redução na rotação basal do VE no grupo TREINO em comparação ao grupo CONTROLE (5,9±2,3 vs. 7,5±2.9o; p=0,03), bem como na velocidade rotacional basal (53,6±18,4 vs. 68,8± 22,1 º/s; p=0,01), velocidade de twist (127,4±32,2 vs. 149,9±35,9 º/s; p=0,02) e na torção (2,4±0,4 vs. 2,8±0, º/cm; p=0,02). Conclusões A atividade física não causou melhora significativa nos parâmetros de deformação longitudinal, radial ou circunferencial do VE. No entanto, o exercício teve um impacto significativo sobre a mecânica de torção do VE, que consistiu em uma redução na rotação basal, na velocidade de twist, na torção, e na velocidade de torção, que pode ser interpretada como uma "reserva" de torção ventricular nessa população.

Abstract Background Exercise plays a positive role in the course of the ischemic heart disease, enhancing functional capacity and preventing ventricular remodeling. Objective To investigate the impact of exercise on left ventricular (LV) contraction mechanics after an uncomplicated acute myocardial infarction (AMI). Methods A total of 53 patients was included, 27 of whom were randomized to a supervised training program (TRAINING group), and 26 to a CONTROL group, who received usual recommendations on physical exercise after AMI. All patients underwent cardiopulmonary stress testing and a speckle tracking echocardiography to measure several parameters of LV contraction mechanics at one month and five months after AMI. A p value < 0.05 was considered statistically significant for the comparisons of the variables. Results No significant difference were found in the analysis of LV longitudinal, radial and circumferential strain parameters between groups after the training period. After the training program, analysis of torsional mechanics demonstrated a reduction in the LV basal rotation in the TRAINING group in comparison to the CONTROL group (5.9±2.3 vs. 7.5±2.9o; p=0.03), and in the basal rotational velocity (53.6±18.4 vs.68.8±22.1 º/s; p=0.01), twist velocity (127.4±32.2 vs. 149.9±35.9 º/s; p=0.02) and torsion (2.4±0.4 vs. 2.8±0.8 º/cm; p=0.02). Conclusions Physical activity did not cause a significant improvement in LV longitudinal, radial and circumferential deformation parameters. However, the exercise had a significant impact on the LV torsional mechanics, consisting of a reduction in basal rotation, twist velocity, torsion and torsional velocity which can be interpreted as a ventricular "torsion reserve" in this population.

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023. / Posicionamento do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia sobre o Uso do Strain Miocárdico na Rotina do Cardiologista ­ 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.

Figura Central : Posicionamento do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia sobre o Uso do Strain Miocárdico na Rotina do Cardiologista ­ 2023 Proposta de inclusão do strain no algoritmo integrado de avaliação da função diastólica, adaptado e traduzido de Nagueh et al. 67 AE: átrio esquerdo; Ap: duração da onda A reversa pulmonar; Am: duração da onda A mitral; DD: disfunção diastólica; FEVEr: fração de ejeção do ventrículo esquerdo reduzida; IT: insuficiência tricúspide; SAEr: strain do AE de reservatório; SLGVE: strain longitudinal global do ventrículo esquerdo. Se remodelamento concêntrico, confirmar com SLGVE. Na presença de FEVEr, tempo de desaceleração da onda E mitral (TDE) < 160 ms e onda S < D pulmonar também são parâmetros de pressão de enchimento aumentada. Esse algoritmo não se aplica a pacientes com fibrilação atrial (FA), calcificação do anel mitral ou valvopatia mitral maior que discreta, bloqueio de ramo esquerdo (BRE), ritmo de marca-passo, próteses valvares ou hipertensão pulmonar (HP) primária grave.

COVID-19 containment management strategies in a nursing home.

OBJECTIVE: To describe the first COVID-19 pandemic at Casa Ondina Lobo, a philanthropic nursing home in São Paulo city, and the containment measures against the pandemic that proved to be effective. METHODS: Several preventive measures were taken before and during the pandemic, with emphasis on universal testing by reverse transcription polymerase chain reaction for COVID-19. All residents and employees were tested twice in a D9 period. RESULTS: Among the 62 residents and 55 employees, in both testing, eight residents and nine employees tested positive for COVID-19. Of 22% of employees and 75% of residents evolved asymptomatic, emphasizing the importance of universal testing for the detection and isolation of these cases. A quarter of residents evolved without any symptoms, however, with COVID-19 signs, reinforcing the importance of monitoring vital signs. The second testing did not detect any new cases among residents, demonstrating the effectiveness of the containment measures, however, it found four new cases among employees. This emphasized their role in COVID-19 outbreaks in nursing homes. Only one patient died, a 12.5% lethality among those known to be infected and a 1.6% mortality in the total population of residents were seen. CONCLUSION: The adoption of appropriate containment measures enabled to contain an COVID-19 pandemic in studied nursing home. Universal reverse transcription polymerase chain reaction testing for COVID-19 has proved to be particularly important and effective.

COVID-19 containment management strategies in a nursing home

ABSTRACT Objective: To describe the first COVID-19 pandemic at Casa Ondina Lobo, a philanthropic nursing home in São Paulo city, and the containment measures against the pandemic that proved to be effective. Methods: Several preventive measures were taken before and during the pandemic, with emphasis on universal testing by reverse transcription polymerase chain reaction for COVID-19. All residents and employees were tested twice in a D9 period. Results: Among the 62 residents and 55 employees, in both testing, eight residents and nine employees tested positive for COVID-19. Of 22% of employees and 75% of residents evolved asymptomatic, emphasizing the importance of universal testing for the detection and isolation of these cases. A quarter of residents evolved without any symptoms, however, with COVID-19 signs, reinforcing the importance of monitoring vital signs. The second testing did not detect any new cases among residents, demonstrating the effectiveness of the containment measures, however, it found four new cases among employees. This emphasized their role in COVID-19 outbreaks in nursing homes. Only one patient died, a 12.5% lethality among those known to be infected and a 1.6% mortality in the total population of residents were seen. Conclusion: The adoption of appropriate containment measures enabled to contain an COVID-19 pandemic in studied nursing home. Universal reverse transcription polymerase chain reaction testing for COVID-19 has proved to be particularly important and effective.

Global Longitudinal Strain or Left Ventricular Twist and Torsion? Which Correlates Best with Ejection Fraction?

Background: Estimative of left ventricular ejection fraction (LVEF) is a major indication for echocardiography. Speckle tracking echocardiography (STE) allows analysis of LV contraction mechanics which includes global longitudinal strain (GLS) and twist/torsion, both the most widely used. Direct comparison of correlations between these novel parameters and LVEF has never been done before. Objective: This study aims to check which one has the highest correlation with LVEF. Methods: Patients with normal LVEF (> 0,55) and systolic dysfunction (LVEF <0,55) were prospectively enrolled, and underwent echocardiogram with STE analysis. Correlation of variables was performed by linear regression analysis. In addition, correlation among levels of LV systolic impairment was also tested. Results: A total of 131 patients were included (mean age, 46 ± 14y; 43%, men). LVEF and GLS showed a strong correlation (r = 0.95; r2 = 0.89; p < 0.001), more evident in groups with LV systolic dysfunction than those with preserved LVEF. Good correlation was also found with global longitudinal strain rate (r = 0.85; r2 = 0.73; p < 0.001). Comparing to GLS, correlation of LVEF and torsional mechanics was weaker: twist (r = 0.78; r2 = 0.60; p < 0.001); torsion (r = 0.75; r2 = 0.56; p < 0.001). Conclusion: GLS of the left ventricle have highly strong positive correlation with the classical parameter of ejection fraction, especially in cases with LV systolic impairment. Longitudinal strain rate also demonstrated a good correlation. GLS increments analysis of LV systolic function. On the other hand, although being a cornerstone of LV mechanics, twist and torsion have a weaker correlation with LV ejection, comparing to GLS.

Fundamento: A estimativa da fração de ejeção do ventrículo esquerdo (FEVE) é uma das pincipais indicações para a ecocardiografia. Speckle tracking (ST) permite a análise da mecânica de contração do VE que inclui a deformação (strain) longitudinal global (SLG) e o twist / torção, sendo ambos os mais utilizados. A comparação direta de correlações entre esses novos parâmetros e a FEVE nunca foi feita antes. Objetivo: Verificar qual delas tem a maior correlação com a FEVE. Métodos: Pacientes com FEVE normal (> 0,55) e disfunção sistólica (FEVE < 0,55) foram prospectivamente inscritos e submetidos a ecocardiograma com análise do ST. A correlação das variáveis foi realizada por análise de regressão linear. Além disso, também foi testada a correlação entre os níveis de comprometimento sistólico do VE. Resultados: Foram incluídos 131 pacientes (média de idade de 46 ± 14 anos e 43% de homens). A FEVE e SLG apresentaram forte correlação (r = 0,95; r2 = 0,89; p < 0,001), mais evidente em grupos com disfunção sistólica do VE do que naqueles com FEVE preservada. Também foi encontrada boa correlação com a taxa de deformação (strain rate) longitudinal (SRL) global (r = 0,85; r2 = 0,73; p < 0,001). Comparando-a à SLG, a correlação entre FEVE e mecânica de torção foi mais fraca: twist (r = 0,78; r2 = 0,60; p < 0,001); Torção (r = 0,75, r2 = 0,56, p < 0,001). Conclusão: A SLG do ventrículo esquerdo apresenta alta correlação positiva com o parâmetro clássico de fração de ejeção, principalmente nos casos de comprometimento sistólico do VE. O SRL também demonstrou uma boa correlação. A SLG incrementa a análise da função sistólica do VE. Por outro lado, apesar de ser a pedra angular da mecânica do VE, o twist e a torção têm uma correlação mais fraca com a ejeção do VE, quando comparados ao SLG.

Global Longitudinal Strain or Left Ventricular Twist and Torsion? Which Correlates Best with Ejection Fraction? / Strain Longitudinal Global ou Twist do Ventrículo Esquerdo e Torção? Qual se Correlaciona Melhor com a Fração de Ejeção?

Abstract Background: Estimative of left ventricular ejection fraction (LVEF) is a major indication for echocardiography. Speckle tracking echocardiography (STE) allows analysis of LV contraction mechanics which includes global longitudinal strain (GLS) and twist/torsion, both the most widely used. Direct comparison of correlations between these novel parameters and LVEF has never been done before. Objective: This study aims to check which one has the highest correlation with LVEF. Methods: Patients with normal LVEF (> 0,55) and systolic dysfunction (LVEF <0,55) were prospectively enrolled, and underwent echocardiogram with STE analysis. Correlation of variables was performed by linear regression analysis. In addition, correlation among levels of LV systolic impairment was also tested. Results: A total of 131 patients were included (mean age, 46 ± 14y; 43%, men). LVEF and GLS showed a strong correlation (r = 0.95; r2 = 0.89; p < 0.001), more evident in groups with LV systolic dysfunction than those with preserved LVEF. Good correlation was also found with global longitudinal strain rate (r = 0.85; r2 = 0.73; p < 0.001). Comparing to GLS, correlation of LVEF and torsional mechanics was weaker: twist (r = 0.78; r2 = 0.60; p < 0.001); torsion (r = 0.75; r2 = 0.56; p < 0.001). Conclusion: GLS of the left ventricle have highly strong positive correlation with the classical parameter of ejection fraction, especially in cases with LV systolic impairment. Longitudinal strain rate also demonstrated a good correlation. GLS increments analysis of LV systolic function. On the other hand, although being a cornerstone of LV mechanics, twist and torsion have a weaker correlation with LV ejection, comparing to GLS.

Resumo Fundamento: A estimativa da fração de ejeção do ventrículo esquerdo (FEVE) é uma das pincipais indicações para a ecocardiografia. Speckle tracking (ST) permite a análise da mecânica de contração do VE que inclui a deformação (strain) longitudinal global (SLG) e o twist / torção, sendo ambos os mais utilizados. A comparação direta de correlações entre esses novos parâmetros e a FEVE nunca foi feita antes. Objetivo: Verificar qual delas tem a maior correlação com a FEVE. Métodos: Pacientes com FEVE normal (> 0,55) e disfunção sistólica (FEVE < 0,55) foram prospectivamente inscritos e submetidos a ecocardiograma com análise do ST. A correlação das variáveis foi realizada por análise de regressão linear. Além disso, também foi testada a correlação entre os níveis de comprometimento sistólico do VE. Resultados: Foram incluídos 131 pacientes (média de idade de 46 ± 14 anos e 43% de homens). A FEVE e SLG apresentaram forte correlação (r = 0,95; r2 = 0,89; p < 0,001), mais evidente em grupos com disfunção sistólica do VE do que naqueles com FEVE preservada. Também foi encontrada boa correlação com a taxa de deformação (strain rate) longitudinal (SRL) global (r = 0,85; r2 = 0,73; p < 0,001). Comparando-a à SLG, a correlação entre FEVE e mecânica de torção foi mais fraca: twist (r = 0,78; r2 = 0,60; p < 0,001); Torção (r = 0,75, r2 = 0,56, p < 0,001). Conclusão: A SLG do ventrículo esquerdo apresenta alta correlação positiva com o parâmetro clássico de fração de ejeção, principalmente nos casos de comprometimento sistólico do VE. O SRL também demonstrou uma boa correlação. A SLG incrementa a análise da função sistólica do VE. Por outro lado, apesar de ser a pedra angular da mecânica do VE, o twist e a torção têm uma correlação mais fraca com a ejeção do VE, quando comparados ao SLG.

Indeterminate form of Chagas disease: is left ventricular torsional mechanics a clue to subclinical myocardial abnormalities?

BACKGROUND: Chagas disease (CD) is highly endemic in Latin America, and has been emerging in developed countries. Early diagnosis of left ventricular (LV) systolic dysfunction, routinely done by echocardiography, is crucial for therapy. Speckle tracking echocardiography allows determination of LV segmental rotations, twist/torsion, and this analysis may disclose an unapparent myocardial contractile deficit in initial stages of CD. Therefore, this study aimed to highlight a possible unapparent myocardial contractile deficit in CD indeterminate form (IF) by a comprehensive torsional mechanics analysis. METHODS: Patients with CDIF diagnosis, initial chagasic cardiomyopathy (CCMP characterized by ECG abnormalities and LVEF > 0.55), and normal controls were prospectively enrolled, and underwent conventional echocardiogram with images acquisition for STE offline analysis. Target parameters were basal and apical rotations, and calculation of twist and torsion. RESULTS: A total of 42 patients were included (CDIF, eight; CCMP, 13; and 21 controls). Chagasic patients had a mean age of 55 years, five (24 %) men, and controls, 50 years, seven (33 %) men. Torsional mechanics analyzes resulted in no significant difference in all parameters studied between groups. Twist in CDIF was 20.8° ± 6.5°; CCMP, 19.0° ± 3.5° and controls, 19.7° ± 3.7° (p = 0.67). Torsion in CDIF was 2.6° ± 0.8°; CCMP, 2.4° ± 0.6° and controls, 2.4° ± 0.5° (p = 0.63). CONCLUSIONS: Patients with Chagas disease have no abnormalities in torsional mechanics during its indeterminate and initial cardiomyopathy stages.

Ultrassom e microbolhas na recanalização de artérias coronarianasno infarto agudo do miocárdio / Ultrasound and microbubbles for coronary artery recanalization in acute myocardial infarction

Fundamento: Microbolhas intravenosas (MB) e ultrassom (US) têm sido utilizados para recanalizar vasos epicárdicos em modelos animais de infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAM-SST). Nenhum estudo prévio demonstrando o valor dessa técnica foi realizado em humanos. Objetivo: Estudo piloto realizado com o objetivo de avaliar a eficácia da utilização de MB e US (sonotrombólise) sobre as taxas iniciais de recanalização de artérias coronarianas em pacientes com IAM-SST. Método: Estudamos 24 pacientes (18 homens, média etária de 58 ± 9 anos) que deram entrada no serviço de emergência com IAM-SST. Pacientes foram randomizados em um dos três grupos: MB + US especificamente desenvolvido para este protocolo, com duração de pulso 4-20 useg e índice mecânico (IM) >1.0 (n = 7), MB + US com impulsos repetitivos de alto IM (1.0), com duração de pulso < 2 useg (n = 8), ou grupo controle (n = 9) que recebeu MB + US apenas paraanalisar a perfusão dentro da área de risco. As MB utilizadas no estudo consistiam em solução de Definity 3%. Todos os pacientes foram submetidos a intervenção coronariana percutânea (ICP). Resultados: As médias dos tempos porta-balão foram 76 ± 35 minutos no grupo MB + US 4-20 useg, 70 ± 20 minutos no grupo MB + US impulsos repetitivos e 81 ± 13 minutos no grupo controle (p = NS). Recanalização angiográfica antes da angioplastia foi observada em 75% dos pacientes tratados com MB + US impulsos repetitivos, em 43% nogrupo tratado com MB + US 4-20 useg e em 11% do grupo controle (p = < 0,05). Conclusão: Utilização de MB e US com impulsos repetitivos pode ser um método para recanalização precoce de artérias epicárdicas em pacientes com IAM-SST.

Background: Intravenous microbubbles (MB) and transthoracic ultrasound (US) have been utilized to recanalize epicardial vessels in animalmodels of ST segment elevation myocardial infarction (STEMI). The feasibility of such an ultrasound-guided approach in humans with STEMIhave not been studied. Objective: Pilot study with the aim to evaluate the efficacy of MB plus US on coronary artery recanalization rate in patients with STEMI. Methods: Twenty-four patients (18 men, mean age 58 ± 9 years) admitted to the emergency room with STEMI were randomized into 3 groups. Patients either received MB plus custom designed high mechanical index (MI) impulses at 4-20 usec pulse duration (n = 7), MB plus diagnostichigh MI (MI = 1.0) with multiple impulses < 2 usec pulse duration (n = 8) or MB plus limited diagnostic high MI impulses (< 5) just to analyzemyocardial perfusion, control group (n = 9). MB utilized in the study consisted of a solution of Definity 3%. All randomized groups underwent emergent PCI.Results: The mean door-to-balloon time were 76 ± 35 minutes in group US 4-20 usec, 70 ± 20 minutes in group US multiple impulses and 81 ± 13 minutes in control group (p = NS). Angiographic recanalization before PCI was observed in 75% of patients treated with US multiple impulses, in 43% for US 4-20 usec and 11% in control (p = <0.05).Conclusion: Utilization of MB and diagnostic US with multiple impulses may be a method of achieving early recanalization in acute STEMI.

The impact of ligation of proximal side branches on blood flow and functional status of the internal thoracic artery in coronary anastomosis.

BACKGROUND: The effect of proximal side branches on the patency of the internal thoracic artery (ITA) is controversial. We used echocardiography and Doppler to verify the effect of ligation of branches on the flow and coronary flow reserve (CFR) of the grafted ITA in patients after coronary artery bypass grafting (CABG). METHODS: We prospectively investigated 53 patients with preserved left ventricular ejection fraction (LVEF >50%) who underwent CABG of the ITA. In Group I (25 patients), major branches were ligated during ITA anastomosis to the left anterior descending (LAD) coronary artery, whereas no ligation was performed in Group II (28 patients). Systolic flow (SF), diastolic flow (DF), and total flow (TF = SF + DF) were measured by Doppler echocardiography at the proximal level of the ITA preoperatively, at early postoperative stage, and 6 months after surgery. Dobutamine stress echocardiography (DSE) was performed at 6 months to determine CFR. RESULTS: The ITA flow was predominantly systolic before surgery and diastolic in the postoperative period. We found no differences between the groups in DF. On DSE, SF (19.5±9 mL/min vs 32.7±19 mL/min; P=.003) and TF (79±21 mL/min vs 101±47 mL/min; P=.037) were higher in Group II. There were no differences in CFR (1.9±0.46 vs 2.11±0.56; P=.143). CONCLUSION: In patients with preserved LVEF, ligation of major side branches during anastomosis to the LAD does not alter ITA flow or CFR.

Comprehensive left ventricular mechanics analysis by speckle tracking echocardiography in Chagas disease.

BACKGROUND: Chagas disease (CD) is a frequent cause of dilated cardiomyopathy (CMP) in developing countries, leading to clinical heart failure and worse prognosis. Therefore, the development and evolution of this CMP has always been a major topic in numbers of previous studies. A comprehensive echocardiographic study of left ventricular (LV) mechanics, fully assessing myocardial contraction, has never been done before. This could help characterize and improve the understanding of the evolution of this prevalent CMP. METHODS: A total of 47 chagasic and 84 control patients were included in this study and allocated in groups according to LV ejection fraction. 2D-Echocardiogram was acquired for LV mechanics analysis by speckle tracking echocardiography. RESULTS: Mean age of chagasic individuals was 55y and 16 (34 %) were men. Significant difference was found in global longitudinal velocity analysis, with lower values in indeterminate form. In the group with severe systolic dysfunction, a paradoxical increase in longitudinal and apical radial displacements were demonstrated. In parallel, segmental analyzes highlighted lower values of radial displacement, strain and strain rate into inferior and inferolateral walls, with increase of these values in septal and anterior walls. CONCLUSION: Chagasic CMP has a vicarious pattern of contraction in the course of its evolution, defined by reduced displacement and strain into inferior and posterior walls with paradoxical increase in septal and anterior segments. Also, lower longitudinal velocities were demonstrated in CD indeterminate form, which may indicate an incipient myocardial injury.

Predominance of Intrinsic Mechanism of Resting Heart Rate Control and Preserved Baroreflex Sensitivity in Professional Cyclists after Competitive Training.

Different season trainings may influence autonomic and non-autonomic cardiac control of heart rate and provokes specific adaptations on heart's structure in athletes. We investigated the influence of transition training (TT) and competitive training (CT) on resting heart rate, its mechanisms of control, spontaneous baroreflex sensitivity (BRS) and relationships between heart rate mechanisms and cardiac structure in professional cyclists (N = 10). Heart rate (ECG) and arterial blood pressure (Pulse Tonometry) were recorded continuously. Autonomic blockade was performed (atropine-0.04 mg.kg-1; esmolol-500 µg.kg-1 = 0.5 mg). Vagal effect, intrinsic heart rate, parasympathetic (n) and sympathetic (m) modulations, autonomic influence, autonomic balance and BRS were calculated. Plasma norepinephrine (high-pressure liquid chromatography) and cardiac structure (echocardiography) were evaluated. Resting heart rate was similar in TT and CT. However, vagal effect, intrinsic heart rate, autonomic influence and parasympathetic modulation (higher n value) decreased in CT (P≤0.05). Sympathetic modulation was similar in both trainings. The autonomic balance increased in CT but still showed parasympathetic predominance. Cardiac diameter, septum and posterior wall thickness and left ventricular mass also increased in CT (P<0.05) as well as diastolic function. We observed an inverse correlation between left ventricular diastolic diameter, septum and posterior wall thickness and left ventricular mass with intrinsic heart rate. Blood pressure and BRS were similar in both trainings. Intrinsic heart rate mechanism is predominant over vagal effect during CT, despite similar resting heart rate. Preserved blood pressure levels and BRS during CT are probably due to similar sympathetic modulation in both trainings.