Strain Magnitude Assessed at Rest and During Stress Echocardiography in Patients with Normal Coronary Flow Reserve

Abstract Background Coronary flow and myocardial contractile performance assessed by strain magnitude increase during a dobutamine stress echocardiogram (DSE). Normal coronary flow reserve (CFR) can be attained upon completion of a DSE at age-predicted maximum heart rate (HR) (HRmax = 220 - age)] or submaximal HR [(0.85) HRmax] or before completion (early CFR). Objective To ascertain the association between delta strain and HR in patients with early normal CFR. Methods This prospective study included patients whose normal CFR was obtained before the DSE was completed. Percentage of resting HR (%HRrest) = [(HRrest ÷ HRmax) 100]% and %HR CFR = [(HR at the time of CFR attainment) ÷ (HRmax) 100]% were recorded. Strain was assessed in the left ventricular region of interest, and delta strain was calculated as the difference between the measures obtained at HRrest and after the DSE was completed. Strain agreement analysis for HRrest, %HRrest, and %HR CFR was performed using the kappa coefficient. The Shapiro-Wilk test was used to assess data normality, and the Mann-Whitney test was used to compare the groups. A p-value < 0.05 was considered statistically significant. Results Strain measured -23.3% ± 4.3% at baseline and -31.1% ± 4.9% during the DSE. In delta strain > 8 absolute points, the ROC curves showed an area under the curve of 0.874 ± 0.07 for %HRrest (p = 0.001) and an area under the curve of 0.862 ± 0.07 for %HR CFR (p = 0.001). In delta strain > 8 points, %HRrest ≤ 42.6% of HRmax and %HR CFR ≤ 62.5% of HRmax showed an accuracy of 82.9% and 79.8%, respectively. Conclusion In this study, lower HRrest and HR at the time of CFR attainment had a good association with better myocardial contractile performance, according to the change in strain magnitude.

Reserva contráctil por fracción de eyección sola, o con elastancia. ¿Cuál es el mejor predictor de eventos luego de un Eco Estrés sin isquemia? / Contractile Reserve by Left Ventricular Ejection Fraction Alone, o Considering Elastance. ¿Which is the Best Predictor of Events After a Stress Echo Without Ischemia?

RESUMEN Introducción: El comportamiento de la fracción de eyección del ventrículo izquierdo (FEVI) durante el ejercicio se utiliza para medir la reserva contráctil (RC). La RC medida por elastancia podría tener mayor valor pronóstico. Objetivo: Establecer si la medición de la RC por elastancia añade valor pronóstico a largo plazo en relación al comportamiento aislado de la FEVI en pacientes con un Eco Estrés sin isquemia miocárdica. Material y métodos: Estudio retrospectivo, realizado en 904 pacientes con Eco Estrés con ejercicio sin isquemia. Se valoró la RC por FEVI y por elastancia. Se dividieron en 2 grupos: Grupo 1: RC por FEVI presente (a su vez este grupo se dividió en 2 subgrupos: Grupo 1 A, RC con elastancia presente y Grupo 1B: ausencia de RC por elastancia), y Grupo 2: pacientes con ausencia de RC por FEVI. El seguimiento fue de 17,7 ± 5,4 meses. Se consideraron como eventos: muerte, infarto agudo de miocardio (IAM), accidente cerebrovascular (ACV) y/o internación de causa cardiovascular. Resultados: Del total del Grupo 1 (536 pacientes), 200 (37,3%) se incluyeron en el Grupo 1A y 336 (62,7%) en el Grupo 1B. En el Grupo 2, se incluyeron 368 pacientes. En el seguimiento, los pacientes del Grupo 2 tuvieron más eventos, 30 (8,1%) vs. 22 (2,6%) (HR 3,14, IC95% 1,95-5,9, log rank test p<0,001). Dentro del G1, los pacientes del Grupo 1B presentaron más eventos: 18 (5,3%) vs 4 eventos (2%) (HR 2,46 IC95% 1,06-7,3, log rank test p<0,05). En el modelo de regresión, la elastancia fue la única variable predictora de eventos (HR 3,2, IC95% 1,83-5,6, p<0,001). Conclusiones: En el Eco Estrés ejercicio negativo para isquemia, el comportamiento de la RC evaluada por elastancia permitió identificar un subgrupo de peor pronóstico a largo plazo en pacientes con comportamiento normal de la FEVI.

ABSTRACT Background: The behavior of left ventricular ejection fraction (LVEF) during exercise is used to measure contractile reserve (CR). CR measured by elastance could have greater prognostic value. Objective: To establish whether the measurement of CR by elastance adds long-term prognostic value to CR measured by LVEF in patients with a Stress Echo without myocardial ischemia. Material and methods: Retrospective study, carried out in 904 patients with an exercise Stress Echo without ischemia. CR was assessed by LVEF and by elastance. Patients were divided into 2 groups: Group 1: presence of CR by LVEF (in turn this group was divided into 2 subgroups: Group 1A, CR with elastance present, and Group 1B: absence of CR by elastance), and Group 2: patients with absence of CR by LVEF. The follow-up was 17,7 ± 5,4 months. Outcomes considered were death, acute myocardial infarction (AMI), stroke, and cardiovascular hospitalization. Results: 536 patients were included in Group 1, 200 (37,3 %) in Group 1A and 336 (62,7%) in Group 1B. In Group 2, 368 patients were included. At follow-up, patients in Group 2 had more events, 30 (8.1%) vs. 22 (2.6%) (HR 3.14, 95% CI 1.95-5.9, log rank test p <0.001). Within G1, patients in Group 1B presented more events: 18(5.3%) vs 4 (2%) (HR 2.46 CI 95% 1.06-7.3, log rank test p <0.05). In the regression model, CR assessed by LVEF and additionally by elastance was the only significant outcome predictor (HR 3.2, 95% CI 1.83-5.6, p <0.001). Conclusions: In an exercise Stress Echo negative for ischemia, CR behavior evaluated by elastance allowed us to identify a subgroup with a worse long-term prognosis in patients with normal LVEF response.

Effects of Hyperthyroidism on Contractility and Na+/Ca2+ Exchanger Activity in the Isolated Papillary Muscle of Rats

Abstract Background: Hyperthyroidism (Hy) is an endocrine disorder, in which the thyroid hormones markedly alter the cardiac function. Increased myocardial contractility and cardiac output, improvement in diastolic relaxation, changes in electrical activity, increments in ventricular mass, and arrhythmias have been reported. However, the influences of thyroid hormones upon molecular mechanisms of cardiac functions have not yet been fully understood. Objectives: To evaluate changes in cardiac contractile parameters and the Na+/Ca2+ exchanger (NCX) function in induced hyperthyroid rats. Methods: Hy was induced by intraperitoneal injections of T3 (15 μg/100 g) for 10 days. Contractile parameters and NCX function were evaluated in the isolated papillary muscle. Data normality was confirmed by the Shapiro-Wilk test. The comparison between groups was performed through an unpaired Student's t-test. Results are expressed as mean ± SD. The accepted significance level was p < 0.05. Results: Our data revealed, in the Hy group, an increase of 30.98% in the maximum speed of diastolic relaxation (-284.64 ± 70.70 vs. -217.31 ± 40.30 mN/mm2/sec (p = 0.027)) and a boost of 149% in the NCX function in late phase of relaxation (20.17 ± 7.90 vs. 50.22 ± 11.94 minutes (p = 0.002)), with no changes in the maximum twitch force (p = 0.605) or maximum speed of systolic contraction (p = 0.208) when compared to the control. Conclusion: The improvement in relaxation parameters is hypothetically attributed to an increase in Sarco-Endoplasmic Reticulum Ca2+ATPase isoform 2 (SERCA2) expression and an increased calcium flow through L-type channels that boosted the NCX function.

Trabalho Miocárdio: uma revisão sistemática do novo método de ecocardiografia e aplicações clínicas / Myocardial Work: a systematic review of novel echocardiography method and clinical applications

Fundamento: O trabalho miocárdico (MW) é uma nova modalidade de imagem que surgiu como uma forma potencial de avaliação da função ventricular esquerda (VE) em vários cenários clínicos. Ele calcula curvas de tensão de ecocardiografia de rastreamento de manchas (STE) com uma curva de pressão LV estimada utilizando curvas padrão de pressão arterial braquial de forma não invasiva. Objetivo: O objetivo desta pesquisa foi fornecer um resumo do conhecimento atual da MW não invasiva e suas aplicações clínicas, incluindo insuficiência cardíaca (IC), doença arterial coronariana (DAC), cardiomiopatia (CMP) e hipertensão (HTN). Além disso, são discutidas as limitações e recomendações da MW na prática clínica. Métodos: Pesquisamos no banco de dados online PubMed para nossa coleta de dados. Usamos as seguintes palavras-chave; (trabalho construtivo do miocárdio) OU (trabalho septal desperdiçado)) OU (trabalho miocárdico global)) OU (trabalho miocárdico)) OU (trabalho construtivo do miocárdio) OU (ecocardiografia nova). Revisamos ainda doze estudos com leitura de texto completo e incluídos nesta revisão sistemática. Resultados: Embora os índices de MW, particularmente GWI e GCW, tenham mostrado uma boa correlação com FE e parâmetros de deformação, a oportunidade de oferecer informações incrementais que não são afetadas pelas condições de carga tornou a aplicação de MW particularmente útil em uma variedade de configurações clínicas. Conclusão: Comparado ao FE e GLS, o MW é um teste promissor com maior sensibilidade e acurácia na identificação de indivíduos com doença cardiovascular. Os médicos também devem depender dos sintomas e dos achados do ECG até que uma extensa pesquisa multicêntrica validando essa estratégia seja feita para estabelecer o valor incremental da MW na avaliação ecocardiográfica diária. (AU)

Background: Myocardial work (MW) is a novel imaging modality that has emerged as a potential left ventricular (LV) function assessment in various clinical settings. MW calculates speckle-tracking echocardiography strain curves with an estimated LV pressure curve by non-invasively utilizing standard brachial blood pressure curves. Objective: This study aimed to provide a summary of current knowledge of non-invasive MW and its clinical applications, including in heart failure, coronary artery disease, cardiomyopathy, and hypertension. In addition, the limitations, and recommendations of MW in clinical practice are discussed. Methods: We searched the PubMed database using the following keywords: (myocardial constructive work) OR (wasted septal work) OR (global myocardial work) OR (myocardial work) OR (myocardial constructive work) OR (novel echocardiography). We further subjected 12 studies to full-text review and included them in this systematic review. Results: While MW indices, particularly global work index and global constructed work, have shown good correlations with ejection fraction (EF) and strain parameters, the opportunity of offering incremental information that is unaffected by loading conditions has made MW application particularly useful in a variety of clinical settings. Conclusion: Compared to EF and global longitudinal strain, MW is a promising test with higher sensitivity and accuracy for identifying individuals with cardiovascular disease. Clinicians should also evaluate symptoms and electrocardiographic findings until extensive multicenter studies validating this strategy are performed to establish the incremental value of MW in daily echocardiographic assessments.(AU)

Deslocamento linear longitudinal do ventrículo esquerdo comparado ao strain longitudinal global por ressonância magnética cardiovascular / Left ventricular longitudinal linear displacement versus global longitudinal strain on cardiovascular magnetic resonance

Introdução: A função sistodiastólica do ventrículo esquerdo é prognóstica nas doenças cardiovasculares e pode ser avaliada por strain longitudinal global por meio de ecocardiografia e de ressonância magnética cardíaca. O strain longitudinal global pela ressonância magnética cardíaca exige a utilização de software de alto custo. O deslocamento linear longitudinal do ventrículo esquerdo pode ser uma alternativa simples e barata ao strain longitudinal global, porém eles não foram ainda comparados sistematicamente. Objetivo: Comparar o deslocamento linear longitudinal com o strain longitudinal global e fração de ejeção do ventrículo esquerdo em valvopatas aórticos e controles. Métodos: Incluímos 44 participantes (26 valvopatas aórticos/19 controles). O strain longitudinal global utilizou software específico (Circle Cardiovascular Imaging 42) e o deslocamento linear longitudinal apenas medidas lineares de distância entre a base e o ápex do ventrículo esquerdo, gerando deslocamento máximo, velocidade máxima no início da diástole, velocidade na diástase e a relação entre velocidade na diástase e velocidade máxima no início da diástole. Resultados: Deslocamento máximo e velocidade máxima no início da diástole correlacionaram-se com strain longitudinal global (r=0,69 e r=0,65 respectivamente) e com a fração de ejeção do ventrículo esquerdo (r=0,47 e r=0,57, p<0,001 para ambos). Deslocamento máximo e velocidade máxima no início da diástole apresentaram área sob a curva Característica de Operação do Receptor de 0,88 e 0,91 e, no melhor ponto de corte (-0,13 e 0,66), sensibilidade de 72,43% e 57,14% e especificidade 80,65% e 87,10%, respectivamente, quando comparados ao strain longitudinal global. Utilizando a fração de ejeção do ventrículo esquerdo como referência, foram obtidos 0,70 e 0,82, e, no melhor ponto de corte (-0,11 e 0,61), sensibilidade de 75,00% e 50,00% e especificidade 72,97% e 78,38%, respectivamente. Conclusão: O deslocamento linear longitudinal foi semelhante ao strain longitudinal global. O deslocamento máximo derivado do deslocamento linear longitudinal foi o melhor parâmetro na sístole, enquanto a velocidade máxima no início da diástole foi o melhor na diástole, o que possibilita a avaliação da função diastólica pela ressonância magnética cardíaca na rotina clínica de forma rápida e sem custo adicional.(AU)

Background: Left ventricular (LV) systolic diastolic function is prognostic in cardiovascular diseases and can be assessed via global longitudinal strain (GLS) on echocardiography and cardiac magnetic resonance (CMR). However, GLS by CMR requires the use of expensive software. Longitudinal linear displacement (LLD) may be a simple and inexpensive alternative to GLS, but the two have not been systematically compared. Objective: To compare LLD with GLS and LV ejection fraction (LVEF) in aortic valve disease patients and controls. Methods: We included 44 participants (26 with aortic valve disease, 19 controls). GLS was determined using CVI42 software (Circle Cardiovascular Imaging), while the LLD linear measurements of the distance between the base/apex of the LV included maximum displacement (MD), maximum velocity in early diastole (MVED), atrioventricular junction velocity in diastasis (VDS), and VDS/MVED ratio. Results: DM and MVED were correlated with GLS (r=0.69 and r=0.65, respectively) and LVEF (r=0.47 and r=0.57, p<0.001 for both). DM and MVED showed areas under the receiver operating characteristic curve (AUC) of 0.88 and 0.91, and at the best cut-off point (-0.13 and 0.66), sensitivities of 72.43% and 57.14% and specificities of 80.65% and 87.10%, respectively, compared to GLS. Using LVEF as a reference, we obtained AUC of 0.70 and 0.82, and at the best cut-off point (-0.11 and 0.61), sensitivities of 75.00% and 50.00% and specificities of 72.97% and 78.38%, respectively. Conclusion: LLD demonstrated similar performance to that of GLS. MD derived from LLD was the best parameter during systole, while MVED was the best during diastole. Our findings demonstrate the routine, quick, and inexpensive assessment of diastolic function on CMR.(AU)

Advances in fetal echocardiography for cardiac function / 中华围产医学杂志

Fetal echocardiography includes the screening of structural abnormalities of the fetal heart as well as the assessment of cardiac function. Fetal cardiac function can reflect the adaptability of the cardiovascular system and hemodynamics in various conditions, providing more information on the pathophysiology of diseases and enabling timely interventions to improve short- and long-term outcomes in fetuses. Some ultrasound and Doppler indicators have been used to assess fetal cardiac function, but their correlation with fetal cardiovascular diseases is still under investigation. With the development of ultrasound, updated technical methods are constantly emerging. This article reviews the existing methods for evaluating fetal cardiac function and their application.

Efeito Cardiodepressor do Acetato de Eugenil em Coração de Roedor / Cardiodepressive Effect of Eugenyl Acetate in Rodent Heart

Resumo No presente trabalho investigou-se o efeito inotrópico do acetato de eugenil (AE), bem como sua ação sobre a corrente de Ca2+ do tipo L (ICa,L). Os experimentos de contratilidade foram realizados em átrio esquerdo isolado de cobaia exposto às concentrações crescentes da droga (1 a 5.000μM). O AE reduziu a força de contração atrial (IC50=558±24,06μM) de modo dependente de concentração. O efeito do AE sobre a ICa,L também foi avaliado em cardiomiócitos ventriculares isolados de camundongos, utilizando-se a técnica de "patch-clamp". O AE apresentou um efeito inibitório (IC50=1.337±221μM) sobre os canais de Ca2+ sensíveis à voltagem (CaV1.2). Em conclusão, o AE apesenta efeito cardiodepressor que se deve, pelo menos em parte, à diminuição da entrada de Ca2+ nos cardiomiócitos.

El comportamiento del strain longitudinal regional depende de la reserva coronaria en un análisis simultáneo durante el eco-estrés con dipiridamol / The Behavior of Regional Longitudinal Strain Depends on Coronary Flow Reserve in a Simultaneous Analysis during Dipyridamole Stress Echocardiography

RESUMEN Introducción: Está poco estudiado el comportamiento del strain longitudinal regional y global en relación al valor de la reserva coronaria. Objetivos: Comparar el comportamiento del strain longitudinal apical y global con el valor de la reserva coronaria de la arteria descendente anterior y secundariamente comparar estas respuestas con el análisis visual de la motilidad parietal durante el eco-estrés con dipiridamol. Material y métodos: Estudio retrospectivo de 179 pacientes (edad 68,7 ± 7,8), 90 hombres (50,3%). En el pico del efecto de dipiridamol, se midió la reserva coronaria, simultáneamente al strain longitudinal y el análisis visual de la contractilidad. Se organizó a los pacientes en dos grupos: grupo 1: reserva coronaria ≥ 2 y grupo 2: < 2. Strain apical se definió como el promedio de 4 segmentos apicales y global de los 17 segmentos. Se consideró normal a todo incremento del strain. Resultados: Se incluyeron 113 pacientes (63,12%) en el grupo 1 y 66 (36,87%) en el grupo 2. Strain apical: el 96,77% del grupo 1 incrementaron su valor con el apremio, mientras que, en el grupo 2, el 95,31% presentaron una caída (p < 0,0001). Strain global: el 82,8% del grupo 1 presentaron incremento de sus valores, en cambio, en el grupo 2, el 78,8% empeoraron (p < 0,01). Análisis de la motilidad parietal posdipiridamol: el 96,46% del grupo 1 tenían motilidad parietal conservada y el 54,5% del grupo 2 (solo en 4 pacientes aumentó el strain apical). Conclusiones: Se comprobó una estrecha correlación entre la reserva coronaria y el strain longitudinal. El strain longitudinal apical resultó ser superior del global. El strain apical demostró tener una mejor correlación con la reserva coronaria que con el análisis visual de la contractilidad.

ABSTRACT Background: The behavior of regional and global longitudinal strain in relation to the value of the coronary reserve is poorly studied. Objectives: Compare the behavior of the Apical and global longitudinal Strain with the value of the coronary reserve of the anterior descending artery and as a secondary aim compare these responses with the visual analysis of parietal motility during Echo Stress with Dipyridamole. Materials and methods: Retrospective study of 179 patients (age 68.7±7.8), 90 patients (50.3%) were men. At the peak of the dipyridamole effect, the coronary reserve was measured, simultaneously with the Longitudinal Strain and the visual analisis of contractility. Two groups were divided: Group 1: Coronary reserve ≥2 and Group 2: <2. Apical Strain was defined as the average of 4 apical segments and global as the average of the 17 segments. It was considered normal any increased of deformation. Results: 113 patients (63.12%) were included in Group 1 and 66 (36.87%) in Group 2. Strain Apical: 96.77% of Group 1 increased their strain values with the stress, while in group 2, 95.31% presented a worsening strain values (p<0.0001). Global Strain: 82.8% of Group 1 had an increase in their values, while in Group 2, 78.8% showed worsening (p<0.01). Post Dipyridamole parietal Motility Analysis: 96.46% of Group 1 had preserved parietal motility and only 54.5% of Group 2 (4 patients had increased apical Strain in this group). Conclusions: There was a close correlation between the coronary reserve of the anterior descending artery and the contractile reserve evaluated by regional apical longitudinal strain of the 4 apical segments, which was superior to the use of global strain. The Apical Strain showed a better correlation with ADA coronary reserve than with the visual analysis of contractility.

Association between Morphodynamic Variables by Transesophageal Echocardiography and CHA2DS2-Vasc Values

In atrial fibrillation (AF), the CHA2DS2-VASc score calculates the risk for stroke. Di Biase classified the left atrial appendage (LAA), using magnetic resonance imaging, into 4 morphological types and correlated it with cerebrovascular events. Transesophageal echocardiography (TEE) also evaluates LAA and is a more widespread technique. Objective: To evaluate, using TEE, the possibility of characterizing LAA and to analyze its morphological aspects using the CHA2DS2VASc score. Methodology: A total of 247 patients were divided into three groups considering the CHA2DS2-VASc score: Group 1: 0 and 1; Group 2: 2 and 3 and, Group 3: ≥ 4 points. TEE produced the echocardiographic data. LAA was classified into thrombogenic and non-thrombogenic morphologies. In the analysis of statistical tests, a significance level of 5% was adopted. Results: The average age was 50 and 16.2% presented AF. In Group 1, we observed normal variables with a lower prevalence of AF (8.7%, p < 0.001). In group 2, spontaneous contrast was detected in 26.7%, (p < 0.001), thrombus in 6.7% (p = 0.079) and flow velocity in LAA < 0.4 m/s in 22.7% (p < 0.001) of the cases. Group 3 presented the highest percentages of AF (31.8%, p < 0.001), stroke/TIA (77.3%, p < 0.001), EF < 55% (18.2%, p = 0.010) and higher prevalence of thrombogenic type LAA (72.7%, p = 0.014). A higher occurrence of stroke/TIA was observed in patients with thrombogenic LAA (25.2%) compared to the non-thrombogenic group (11.2%), (p = 0.005). Conclusions: The thrombogenic morphology of LAA identified in TEE presented a higher risk of stroke regardless of the CHA2DS2VASc score. Patients with higher scores had greater abnormalities in echocardiographic variables

Modificaciones del trazado electrocardiográfico y la contractilidad cardíaca en pacientes con cardiopatía isquémica rehabilitados mediante ejercicio físico / Modifications of the electrocardiographic tracing and heart contractility in patients with ischemic cardiopathy rehabilitated by means of physical exercise

Se realizó una investigación descriptiva, longitudinal y prospectiva de 41 pacientes con antecedentes de infarto agudo del miocardio, que formaron parte de un programa de rehabilitación cardiovascular en el Servicio de Terapia Física y Rehabilitación del Hospital General Docente Dr Juan Bruno Zayas Alfonso de Santiago de Cuba, desde mayo de 2017 hasta igual mes de 2018, con vistas a evaluar el efecto del entrenamiento físico sobre la función cardiovascular de estos. Se examinó la función cardiovascular a través del ecocardiograma y el electrocardiograma, antes y después de aplicado el programa, y al final del estudio se obtuvo una modificación positiva de las variables eco- y electrocardiográficas, con un mayor grado de recuperación de la contractilidad segmentaria. Pudo concluirse que el programa tuvo un papel importante en la restauración de la función cardíaca y, con ello, se mejoró la capacidad física y psicológica de los pacientes, de manera que fue beneficioso para estos y para la sociedad.

A descriptive, longitudinal and prospective investigation of 41 patients with a history of acute myocardial infarction who were part of a program of cardiovascular rehabilitation in the Service of Physical Therapy and Rehabilitation from Dr Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba was carried out from May, 2017 to the same month in 2018, with the aim of evaluating the effect of the physical training on their cardiovascular function. The cardiovascular function was examined through the echocardiogram and the electrocardiogram, before and after the program was applied, and at the end of the study a positive modification of the echocardiographical and electrocardiographical variables was obtained with a higher degree of recovery of the segmental contractility. It could be concluded that the program had an important role in the restoration of the heart function and, with it, the physical and psychological capacity of the patients improved, so that it was beneficial for them and for the society.

Evaluation of left ventricular myocardial systolic dysfunction in patients with obstructive sleep apnea hypopnea syndrome using three‐dimensional strain echocardiography / 中华超声影像学杂志

Objective To evaluate left ventricular myocardial systolic function in patients with obstructive sleep apnea hypopnea syndrome ( OSA HS) with normal left ventricular ejection fraction( LVEF) using three‐dimensional strain echocardiography . Methods One hundred patients with OSA HS were divided into mild group ,moderate group and severe group according to apnea hypopnea index ( A HI) w hile matched with 32 healthy people as control group . T he parameters such as three‐dimensional LVEF ,global longitudinal strain( GLS) ,global circumferential strain( GCS) ,global area strain( GAS) ,global radial strain ( GRS) ,twist and torsion based on standard three‐dimensional echocardiography were measured by three‐ dimensional strain echocardiography , the above parameters among the four groups were compared for difference .Linear correlationship between A HI ,LVEF and the three dimensional strain parameters was analyzed respectively . Results ①T here was no significant difference in three‐dimensional LVEF ,twist and torsion between each groups( P ＞0 .05 ) . ②GLS ,GAS and GRS were lower in mild ,moderate and severe group compared with control group ,decreasing along with the disease severity ( P ＜0 .01 or P ＜ 0 .05 ) . GCS in severe group was lower than that in control group ( P ＜0 .01 ) . ③GLS and GAS in severe group were lower than those in mild group ( all P ＜0 .05) .GRS in moderate and severe group were lower than that in mild group( all P ＜ 0 .05 ) ,GAS ,GRS in severe group was lower than those in moderate group ( P ＜0 .05) . ④T here was a mild correlation between GLS and A HI ( r ＝0 .342 , P ＜0 .01) ,GAS and A HI ( r＝0 .294 , P ＜0 .01) ,GRS and A HI ( r ＝ －0 .411 , P ＜0 .01 ) . T here was a mild correlation between GCS and three‐dimensional LVEF ( r＝ －0 .354 , P ＜0 .01 ) ,GAS and three‐dimensional LVEF ( r ＝ －0 .326 , P ＜0 .01) ,GRS and three‐dimensional LVEF ( r ＝0 .300 , P ＜0 .01) . Conclusions T he left ventricular myocardial systolic function is impaired in all patients with OSA HS even with normal LVEF and the dysfunction is aggravating with the disease severity . Ultrasonic three‐dimensional strain imaging technology can be used to detect the subclinical myocardial systolic dysfunction quantitatively in the early stage of OSA HS patients .

Influence of Aerobic Training on The Mechanics of Ventricular Contraction After Acute Myocardial Infarction: A Pilot Study / Influência do Treinamento Aeróbico na Mecânica de Contração Ventricular após Infarto Agudo do Miocárdio: Estudo Piloto

Abstract The study of myocardial contractility, based on the new anatomical concepts that govern cardiac mechanics, represents a promising strategy of analysis of myocardial adaptations related to physical training in the context of post-infarction. We investigated the influence of aerobic training on physical capacity and on the evaluation parameters of left ventricular contraction mechanics in patients with myocardial infarction. Thirty-one patients (55.1 ± 8.9 years) who had myocardial infarction in the anterior wall were prospectively investigated in three groups: interval training group (ITG) (n = 10), moderate training group (MTG) n = 10) and control group (CG) (n = 10). Before and after 12 weeks of clinical follow-up, patients underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging. The trained groups performed supervised aerobic training on treadmill, in two different intensities. A statistically significant increase in peak oxygen uptake (VO2) was observed in the ITG (19.2 ± 5.1 at 21.9 ± 5.6 ml/kg/min, p < 0.01) and in the MTG 18.8 ± 3.7 to 21.6 ± 4.5 ml/kg/min, p < 0.01). The GC did not present a statistically significant change in peak VO2. A statistically significant increase in radial strain (STRAD) was observed in the CG: basal STRAD (57.4 ± 16.6 to 84.1 ± 30.9%, p < 0.05), medial STRAD (57.8 ± 27, 9 to 74.3 ± 36.1%, p < 0.05) and apical STRAD (38.2 ± 26.0 to 52.4 ± 29.8%, p < 0.01). The trained groups did not present a statistically significant change of the radial strain. The present study points to a potential clinical application of the parameters of ventricular contraction mechanics analysis, especially radial strain, to discriminate post-infarction myocardial adaptations between patients submitted or not to aerobic training programs.

Resumo O estudo da contratilidade miocárdica, baseado nos novos conceitos anatômicos que regem a mecânica cardíaca, representa uma estratégia promissora de análise das adaptações do miocárdio relacionadas ao treinamento físico no contexto do pós-infarto. Nós investigamos a influência do treinamento aeróbico na capacidade física e nos parâmetros de avaliação da mecânica de contração do ventrículo esquerdo em pacientes com infarto do miocárdio. Foram prospectivamente investigados 30 pacientes, 55,1 ± 8,9 anos, acometidos por infarto do miocárdio de parede anterior, aleatorizados em três grupos: grupo treinamento intervalado (GTI) (n = 10), grupo treinamento moderado (GTM) (n=10) e grupo controle (GC) (n = 10). Antes e após as 12 semanas de seguimento clínico, os pacientes realizaram teste cardiopulmonar de exercício e ressonância magnética cardíaca. Os grupos treinados realizaram treinamento aeróbico supervisionado, em esteira ergométrica, aplicando-se duas intensidades distintas. Observou-se aumento estatisticamente significante do consumo de oxigênio (VO2) pico no GTI (19,2 ± 5,1 para 21,9 ± 5,6 ml/kg/min, p < 0,01) e no GTM (18,8 ± 3,7 para 21,6 ± 4,5 ml/kg/min, p < 0,01). O GC não apresentou mudança estatisticamente significante no VO2 pico. Houve aumento estatisticamente significante do strain radial (STRAD) somente no GC: STRAD basal (57,4 ± 16,6 para 84,1 ± 30,9%, p < 0,05), STRAD medial (57,8 ± 27,9 para 74,3 ± 36,1%, p < 0,05) e STRAD apical (38,2 ± 26,0 para 52,4 ± 29,8%, p < 0,01). Os grupos treinados não apresentaram mudança estatisticamente significante do strain radial. Os achados do presente estudo apontam para uma potencial aplicação clínica dos parâmetros de análise da mecânica de contração ventricular, notadamente do strain radial, em discriminar adaptações do miocárdio pós-infarto entre pacientes submetidos ou não a programas de treinamento aeróbico.

Moderate Continuous Aerobic Exercise Training Improves Cardiomyocyte Contractility in Β1 Adrenergic Receptor Knockout Mice / Treinamento Aeróbico Contínuo de Intensidade Moderada Melhora a Contratilidade do Cardiomiócito em Camundongos com Nocaute para o Receptor B1-Adrenérgico

Abstract Background: The lack of cardiac β1-adrenergic receptors (β1-AR) negatively affects the regulation of both cardiac inotropy and lusitropy, leading, in the long term, to heart failure (HF). Moderate-intensity aerobic exercise (MCAE) is recommended as an adjunctive therapy for patients with HF. Objective: We tested the effects of MCAE on the contractile properties of left ventricular (LV) myocytes from β1 adrenergic receptor knockout (β1ARKO) mice. Methods: Four- to five-month-old male wild type (WT) and β1ARKO mice were divided into groups: WT control (WTc) and trained (WTt); and β1ARKO control (β1ARKOc) and trained (β1ARKOt). Animals from trained groups were submitted to a MCAE regimen (60 min/day; 60% of maximal speed, 5 days/week) on a treadmill, for 8 weeks. P ≤ 0.05 was considered significant in all comparisons. Results: The β1ARKO and exercised mice exhibited a higher (p < 0.05) running capacity than WT and sedentary ones, respectively. The β1ARKO mice showed higher body (BW), heart (HW) and left ventricle (LVW) weights, as well as the HW/BW and LVW/BW than WT mice. However, the MCAE did not affect these parameters. Left ventricular myocytes from β1ARKO mice showed increased (p < 0.05) amplitude and velocities of contraction and relaxation than those from WT. In addition, MCAE increased (p < 0.05) amplitude and velocities of contraction and relaxation in β1ARKO mice. Conclusion: MCAE improves myocyte contractility in the left ventricle of β1ARKO mice. This is evidence to support the therapeutic value of this type of exercise training in the treatment of heart diseases involving β1-AR desensitization or reduction.

Resumo Fundamento: A falta de receptores β1-adrenérgicos (β1-AR) cardíacos afeta negativamente a regulação de inotropismo e lusitropismo cardíacos, levando, no longo prazo, a insuficiência cardíaca (IC). Recomenda-se exercício aeróbico contínuo de intensidade moderada (EACM) como adjuvante no tratamento de pacientes com IC. Objetivo: Testar os efeitos do EACM nas propriedades contráteis de miócitos do ventrículo esquerdo (VE) de camundongos com nocaute para o receptor β1-adrenérgico (β1ARKO). Método: Camundongos machos com 4 a 5 meses de idade, wild-type (WT) e β1ARKO foram divididos em grupos: WT controle (WTc) e treinado (WTt); e β1ARKO controle (β1ARKOc) e treinado (β1ARKOt). Os grupos treinados foram submetidos a regime de EACM (60 min/dia; 60% da velocidade máxima, 5 dias/semana) em esteira rolante, por 8 semanas. Adotou-se P ≤ 0,05 como nível de significância em todas as comparações. Resultados: Os animais β1ARKO (β1ARKOc + β1ARKOt) correram uma distância maior do que os animais WT (WTc + WTt) (p < 0,05). Os camundongos β1ARKO apresentaram maiores pesos corporal (PC), do coração (PCo) e do ventrículo esquerdo (PVE), assim como PCo/PC e PVE/PC do que os camundongos WT. Entretanto, o EACM não afetou tais parâmetros. Os miócitos do VE de camundongos β1ARKO apresentaram maiores (p < 0,05) amplitude e velocidades de contração e relaxamento do que os dos camundongos WT. Além disso, o EACM aumentou (p < 0,05) a amplitude e as velocidades de contração e relaxamento nos camundongos β1ARKO. Conclusão: O EACM melhora a contratilidade do miócito do VE de camundongos β1ARKO. Tal achado confirma o valor terapêutico desse tipo de treinamento físico para o tratamento de doenças cardíacas envolvendo dessensibilização ou redução de β1-AR.

MRI Study of Strain Feature of Left Ventricular Long-axis Myocardium in Normal Young Adults / 中国医学影像学杂志

Purpose To measure the longitudinal and transverse strain and displacement parameters of each segment of long axis myocardium on cardiac MRI film images of normal young volunteers using feature tracking technique (FT), and to analyze the regularity of left ventricular long axis strain and establish peak and time to peak (TTP) reference range concerning the longitudinal and transverse strain and displacement. Materials and Methods Cardiac film images of 29 healthy volunteers aged 24 to 34 were collected using Philips Multiva 1.5T MRI scanner, including three typical long axis planes of the left ventricular long axis, left ventricular outflow tract, and four-chamber view. The MRI film images were analyzed drawing on myocardial feature tracking software TOMTEC, and the peak value and TTP of longitudinal and transverse strain and displacement of the 16 AHA segments excluding apex cordis were obtained thereby. The regularity of each parameter concerning the plane, layer, and segment was summarized and analyzed. Results The TTP of longitudinal strain, longitudinal displacement and transverse strain were consistent among each myocardial segment, which was a constant indicator in (41.24±12.51) ％ RR interphase. The peak value of longitudinal displacement was represented by apex cordis (2.56±0.89) mm < middle (6.09±2.03) mm < cardiac base (8.07±2.05) mm, and the peak value of transverse displacement was manifested as apex cordis (4.57±1.18) mm < middle (5.65±0.84) mm < cardiac base (8.48 ±1.18) mm, which was consistent with cardiac geometric deformation visually observed. The longitudinal strain showed consistency on 2CH-3CH-4CH plane, whose peak reference value was (-22.46±13.19)％; while the peak value of transverse strain displayed no consistency on different planes. Conclusion The longitudinal strain of the left ventricular on different planes has consistent peak value and TTP, suggesting good reference value.