Comparacão dos Parâmetros Ecocardiográficos Convencionais e com Speckle Tracking entre Indivíduos Saudáveis e Transplantados Cardíacos sem Rejeição / Comparative Analysis of Conventional and Speckle Tracking Echocardiographic Variables between Patients with Unrejected Heart Transplants and Healthy Individuals

Resumo Fundamento A ecocardiografia é essencial para avaliação do coração transplantado. No entanto, os valores de normalidade no transplante cardíaco (TC) não estão claramente definidos. Objetivos: Comparar parâmetros ecocardiográficos convencionais e pela técnica de Speckle Tracking entre pacientes transplantados cardíacos sem rejeição e uma população de indivíduos saudáveis. Métodos Foram estudados prospectivamente pacientes adultos, com menos de 1 ano de TC, que realizaram biópsia endomiocárdica de vigilância seguido de ecocardiograma transtorácico (ETT). Medidas convencionais de ETT acrescidas da avaliação de mecânica cardíaca por meio do Strain pelo Speckle Tracking foram realizadas e comparadas com um grupo de voluntários saudáveis. A significância estatística adotada para o estudo foi de 5%. Resultados Avaliou-se 36 pacientes transplantados sem rejeição, os quais foram comparados com 30 indivíduos saudáveis. Observou-se redução nos valores de Strain Global Longitudinal de Ventrículo Esquerdo em valor absoluto (11,99% transplantados, 20,60% controle, p<0,0001), Strain de parede livre de Ventrículo Direito (transplantados 16,67%, controle 25,50%, p<0,0001) e dos índices de trabalho miocárdico (p<0,0001), maior tamanho do átrio esquerdo (38,17 ml/m2 transplantados, controle 18,98 ml/m2, p<0,0001), maior índice de massa e espessura relativa das paredes (p<0,0001) e a presença da Doença de Chagas como principal etiologia para o transplante. Conclusão Os transplantados cardíacos estáveis e sem rejeição apresentaram diferenças com relação aos parâmetros ecocardiográficos comparados com indivíduos saudáveis. Estes achados indicam que medidas ecocardiográficas convencionais e de mecânica cardíaca são alteradas em transplantados mesmo na ausência de rejeição e podem ser relevantes para o contexto clínico e acompanhamento dos pacientes.

Abstract Background Echocardiography is essential for the assessment of patients with heart transplants. However, normal values in such individuals are not clearly defined. Objectives To compare conventional echocardiographic and speckle tracking variables between patients with unrejected heart transplants and healthy individuals. Methods : A prospective study was conducted with adult patients having undergone heart transplantation at least one year earlier and submitted to endomyocardial biopsy followed by transthoracic echocardiogram (TTE). Conventional TTE measures and mechanical heart strain assessments using speckle tracking were performed and the results were compared to those of a group of healthy volunteers. Statistical significance was set at 5% (p < 0.05). Results Thirty-six transplant patients without rejection were analyzed and compared to 30 healthy individuals. Chagas disease was the main reason for transplantation. Lower left ventricular global longitudinal strain expressed in absolute values was found (11.99% in transplant patients vs. 20.60% in controls; p <0.0001), right ventricular free wall longitudinal strain (16.67% in transplant patients vs. 25.50% in controls; p <0.0001) and myocardial work indices (p < 0.0001) as well as a larger size of the left atrium (38.17 ml/m2 in transplant patients vs. 18.98 ml/m2 in controls; p <0.0001) and greater mass and relative wall thickness (p <0.0001). Conclusion Stable patients having undergone heart transplants without rejection have differences concerning echocardiographic variables compared to healthy individuals. These findings indicate that conventional echocardiographic measures and heart mechanics are altered in transplant patients even in the absence of rejection. Such findings are relevant to the clinical context and follow-up of the patient.

Efeitos de Longo Prazo do Implante Valvar Pulmonar e Evolução da Prótese em Pacientes com Tetralogia de Fallot Corrigida / Long-Term Effects of Pulmonary Valve Implantation and Prosthesis Evolution in Patients with Repaired Tetralogy of Fallot

Resumo Fundamento A regurgitação valvar pulmonar é uma importante complicação de longo prazo em pacientes com tetralogia de Fallot (TF). Objetivo O presente estudo tem como objetivo investigar os efeitos do implante valvar pulmonar (IVP) na anatomia e função do ventrículo direito (VD) e na evolução em longo prazo da prótese implantada em posição pulmonar. Métodos Uma análise de coorte retrospectiva e unicêntrica foi realizada em 56 pacientes consecutivos com TF submetidos a IVP. O estudo incluiu pacientes de ambos os gêneros, com idade ≥ 12 anos e compreendeu avaliação de dados clínicos e cirúrgicos, ressonância magnética cardiovascular pré e pós-operatória e dados ecocardiográficos obtidos mais de 1 ano após IVP. Resultados Após o IVP, houve uma diminuição significativa do volume sistólico final do VD indexado pela área de superfície corpórea (ASC), de 89 mL/ASC para 69 mL/ASC (p < 0,001) e do volume diastólico final indexado do VD, de 157 mL/ASC para 116 mL/ASC (p < 0,001). Além disso, houve aumento da fração de ejeção corrigida do VD [ FEVDc = fluxo pulmonar ajustado (fluxo pulmonar anterógrado − fluxo regurgitante) / volume diastólico final do VD ] de 23% para 35% (p < 0,001) e da fração de ejeção do ventrículo esquerdo de 58% para 60% (p = 0,008). No entanto, foi observado um aumento progressivo no gradiente de pico da válvula pulmonar ao longo do tempo, com 25% dos pacientes apresentando um gradiente superior a 60 mmHg. Próteses menores (tamanhos 19 a 23) foram associadas a um risco 4,3 vezes maior de gradiente > 60 mmHg em comparação com próteses maiores (tamanhos 25 a 27; p = 0,029; intervalo de confiança: 1,18 a 17,8). Conclusão Conforme esperado, o IVP demonstrou melhorias nos volumes e na função do VD. O acompanhamento e a vigilância a longo prazo são cruciais para avaliar a durabilidade da prótese e detectar potenciais complicações. O dimensionamento adequado das próteses é essencial para melhorar a longevidade da prótese.

Abstract Background Pulmonary valve regurgitation is a significant long-term complication in patients with tetralogy of Fallot (TOF). Objective This study aims to investigate the effects of pulmonary valve implantation (PVI) on the anatomy and function of the right ventricle (RV) and the long-term evolution of the implanted prosthesis in the pulmonary position. Methods A single-center retrospective cohort analysis was performed in 56 consecutive patients with TOF who underwent PVI. The study included patients of both sexes, aged ≥ 12 years, and involved assessing clinical and surgical data, pre- and post-operative cardiovascular magnetic resonance imaging, and echocardiogram data more than 1 year after PVI. Results After PVI, there was a significant decrease in RV end-systolic volume indexed by body surface area (BSA), from 89 mL/BSA to 69 mL/BSA (p < 0.001) and indexed RV end-diastolic volume, from 157 mL/BSA to 116 mL/BSA (p < 0.001). Moreover, there was an increase in corrected RV ejection fraction [ RVEFC = net pulmonary flow (pulmonary forward flow − regurgitant flow) / R V end-diastolic volume] from 23% to 35% (p < 0.001) and left ventricular ejection fraction from 58% to 60% (p = 0.008). However, a progressive increase in the peak pulmonary valve gradient was observed over time, with 25% of patients experiencing a gradient exceeding 60 mmHg. Smaller prostheses (sizes 19 to 23) were associated with a 4.3-fold higher risk of a gradient > 60 mmHg compared to larger prostheses (sizes 25 to 27; p = 0.029; confidence interval: 1.18 to 17.8). Conclusion As expected, PVI demonstrated improvements in RV volumes and function. Long-term follow-up and surveillance are crucial for assessing the durability of the prosthesis and detecting potential complications. Proper sizing of prostheses is essential for improved prosthesis longevity.

Acetazolamide As A Valuable Addition to Acute Heart Failure?

Consider IV Acetazolamide in addition to standard IV loop diuretic therapy in patients hospitalized for acute decompensated heart failure.1.

Chagas Cardiomyopathy and Myocardial Sympathetic Denervation.

PURPOSE OF REVIEW: More than a century since its discovery, the pathogenesis of Chagas heart disease (CHD) remains incompletely understood. The role of derangements in the autonomic control of the heart in triggering malignant arrhythmia before the appearance of contractile ventricular impairment was reviewed. RECENT FINDINGS: Although previous investigations had demonstrated the anatomical and functional consequences of parasympathetic dysautonomia upon the heart rate control, only recently, coronary microvascular disturbances and sympathetic denervation at the ventricular level have been reported in patients and experimental models of CHD, exploring with nuclear medicine methods their impact on the progression of myocardial dysfunction and cardiac arrhythmias. More important than parasympathetic impaired sinus node regulation, recent evidence indicates that myocardial sympathetic denervation associated with coronary microvascular derangements is causally related to myocardial injury and arrhythmia in CHD. Additionally, 123I-MIBG imaging is a promising tool for risk stratification of progression of ventricular dysfunction and sudden death.

[Correlation of left ventricular contractile function with the presence of collateral coronary circulation in non-reperfused acute myocardial infarction]. / Correlación de la función contráctil del ventrículo izquierdo con la presencia de circulación coronaria colateral en infarto agudo de miocardio no reperfundido.

Objective: To assess the association between coronary collateral circulation and ventricular contractile function in patients with non-reperfused acute myocardial infarction. Method: A retrospective and descriptive clinical study was conducted on patients with ST-elevation myocardial infarction (STEMI) at a reference cardiovascular center, from January 2006 to December 2022. Coronary angiographies and echocardiograms were reviewed to evaluate coronary collateral circulation and ventricular function, respectively. Patients were divided into groups based on the presence of collateral circulation. Both groups were compared and mortality during the index hospitalization was analyzed. Results: Out of a total of 14,985 patients with acute coronary syndrome, 8134 (54.3%) had the diagnosis of STEMI. We excluded 12,880, leaving a total of 2105 non-reperfused STEMI patients who underwent coronary angiography, revealing lesions. There were more patients without collateral circulation: 1547 (73.5%) vs. 558 (26.5%) (p = 0.025). Patients without collateral circulation had a higher left ventricular ejection fraction (median of 47% vs. 42%; p < 0.001). Mortality in patients with collateral circulation was higher compared to those without it (11.6% vs. 9.8%; p = 0.225), but statistical significance was not reached. Conclusions: Non-reperfused STEMI patients did not show protection from collateral circulation when assessing left ventricular systolic function. We did not find a difference in mortality compared to the population without development of collateral circulation.

Objetivo: Evaluar la asociación entre la circulación coronaria colateral y la función contráctil ventricular en pacientes con infarto agudo de miocardio no reperfundido. Método: Estudio observacional descriptivo y retrospectivo en pacientes con infarto agudo de miocardio con elevación del segmento ST (IAMCEST) en un centro cardiovascular de referencia, de enero de 2006 a diciembre de 2022. Se analizaron las coronariografías y los ecocardiogramas para evaluar la circulación coronaria colateral y la función ventricular, respectivamente. Se dividieron en grupos de acuerdo con la presencia de circulación colateral. Se compararon ambos grupos y se analizó la mortalidad durante la hospitalización del evento índice. Resultados: De 14,985 pacientes con síndrome coronario agudo, 8134 (54.3%) presentaron IAMCEST. Se excluyeron 12,880, quedando así 2105 pacientes con IAMCEST no reperfundidos y sometidos a coronariografía, revelando lesiones. Hubo más pacientes sin circulación colateral: 1547 (73.5%) vs. 558 (26.5%) (p = 0.025). Los pacientes sin circulación colateral presentaron una mayor fracción de eyección ventricular izquierda (mediana del 47% vs. 42%; p < 0.001). La mortalidad en los pacientes con circulación colateral fue mayor que en los pacientes sin ella (11.6% vs. 9.8%; p = 0.225), pero no se alcanzó significancia estadística. Conclusiones: Los pacientes con IAMCEST no reperfundidos no presentaron protección por la circulación colateral al evaluar la función sistólica ventricular izquierda. No se encontró diferencia en la mortalidad en comparación con la población sin desarrollo de circulación colateral.

Sociodemographic, Clinical Condition, and Functional Aerobic Capacity in Patients With Heart Failure With Varying Ventricular Ejection Fraction

Abstract Background Recently, a new heart failure (HF) classification was made considering the left ventricular ejection fraction (LVEF) phenotype. Comprehensive assessments of the groups are required to guide patient management. Objective To determine the differences in sociodemographic, clinical, functional aerobic capacity, and health-related quality of life (HRQOL) variables in patients with HF classified with different LVEFs and to explore the correlations between the variables. Methods This work is a cross-sectional descriptive and correlational study. Three groups of patients with HF (LVEF≥50%, LVEF<40%, and LVEF40-49%) were compared. Sociodemographic, clinical variables and functional aerobic capacity with Sit to Stand (STS), 6-minute walk test (6MWT), Duke Activity Status Index (DASI), Minnesota Living with HF Questionnaire (MLFHQ), and Patient Health Questionnaire 9 (PHQ-9) were considered. The Chi-square test, one-way analysis of variance (ANOVA) test, and Spearman's correlation were used for statistical analysis. The statistical significance level was set at 5%. Results A total of 209 patients were admitted with a diagnosis of HF, with a more significant number of men. Marital status was a predominantly stable union in the HF with preserved ejection fraction (HFpEF) and HF with mid-range ejection fraction (HFmrEF) groups. A sedentary lifestyle was lower in the HF with reduced ejection fraction (HFrEF) group 59 (84.3%), p-value = 0.033, and the angina pectoris was higher in the HFpEF 30 (42.9%). Systolic blood pressure at the end of the 6MWT evidenced a higher score in HFpEF 132.0±17.25 concerning HFrEF 128.0±16.57, p-value=0.043. The fat percentage was higher in HFpEF 30.20±8.80 regarding the HFmrEF group 26.51±7.60, p-value = 0.028. Conclusion There were significant differences according to the LVEF classification in marital status, angina symptoms, fat percentage, and blood pressure at rest.

Extracorporeal Membrane Oxygenation Uses in Refractory Cardiogenic Shock After Open-Heart Surgery

ABSTRACT Introduction: Extracorporeal membrane oxygenation (ECMO) is the first-line therapy for temporary mechanical circulatory support allowing cardiac and pulmonary recovery or as a bridge to further therapeutic alternatives. The aim of this study was to report clinical outcomes in adult patients with refractory cardiac failure after open-heart surgery undergoing ECMO in a single center with an ECMO unit in Chile. Methods: We retrospectively analyzed adults with refractory cardiac failure after open-heart surgery who required a venoarterial (VA) ECMO between 2016 and 2021. Results: Of 16 patients with VA ECMO, 60% were men (n=10), 90% had hypertension (n=14), 69% had < 30% of left ventricular ejection fraction (n=11), and the mean European System for Cardiac Operative Risk Evaluation II score was 12 ± 11%. ECMO support with central cannulation accounts for 81% (n=13), and an intra-aortic balloon pump was used in nine patients (56%). The mean time of support was 4.7 ± 2.6 days (1.5 - 12 days). ECMO weaning was achieved in 88% of patients, and in-hospital mortality was 44% (n=7) after discharge. The freedom from all-cause mortality at one year of follow-up of the entire cohort was 38% (n=6). Conclusion: VA ECMO is now a well-known life-saving therapeutic option, but mortality and morbidity remain high. Implementation of an ECMO program with educational training is mandatory in order to find the proper balance between patient benefits, ethical considerations, and public health financial input in South America.

The influence of dapagliflozin on cardiac remodeling, myocardial function and metabolomics in type 1 diabetes mellitus rats.

BACKGROUND: Sodium-glucose cotransporter (SGLT)2 inhibitors have displayed beneficial effects on the cardiovascular system in diabetes mellitus (DM) patients. As most clinical trials were performed in Type 2 DM, their effects in Type 1 DM have not been established. OBJECTIVE: To evaluate the influence of long-term treatment with SGLT2 inhibitor dapagliflozin on cardiac remodeling, myocardial function, energy metabolism, and metabolomics in rats with Type 1 DM. METHODS: Male Wistar rats were divided into groups: Control (C, n = 15); DM (n = 15); and DM treated with dapagliflozin (DM + DAPA, n = 15) for 30 weeks. DM was induced by streptozotocin. Dapagliflozin 5 mg/kg/day was added to chow. STATISTICAL ANALYSIS: ANOVA and Tukey or Kruskal-Wallis and Dunn. RESULTS: DM + DAPA presented lower glycemia and higher body weight than DM. Echocardiogram showed DM with left atrium dilation and left ventricular (LV) hypertrophy, dilation, and systolic and diastolic dysfunction. In LV isolated papillary muscles, DM had reduced developed tension, +dT/dt and -dT/dt in basal condition and after inotropic stimulation. All functional changes were attenuated by dapagliflozin. Hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) activity was lower in DM than C, and PFK and PK activity higher in DM + DAPA than DM. Metabolomics revealed 21 and 5 metabolites positively regulated in DM vs. C and DM + DAPA vs. DM, respectively; 6 and 3 metabolites were negatively regulated in DM vs. C and DM + DAPA vs. DM, respectively. Five metabolites that participate in cell membrane ultrastructure were higher in DM than C. Metabolites levels of N-oleoyl glutamic acid, chlorocresol and N-oleoyl-L-serine were lower and phosphatidylethanolamine and ceramide higher in DM + DAPA than DM. CONCLUSION: Long-term treatment with dapagliflozin attenuates cardiac remodeling, myocardial dysfunction, and contractile reserve impairment in Type 1 diabetic rats. The functional improvement is combined with restored pyruvate kinase and phosphofructokinase activity and attenuated metabolomics changes.

Comparison of Single-Dose Cardioplegia in Valvular Heart Surgery: Lactated Ringer's-Based del Nido vs. Histidine-Tryptophan-Ketoglutarate Cardioplegia Solution.

INTRODUCTION: This study evaluated myocardial protection and clinical outcomes when using lactated Ringer's solution as the base solution for del Nido cardioplegia compared with histidine-tryptophan-ketoglutarate (HTK) solution in valvular surgery. METHODS: From January 2017 to May 2018, 71 adult patients who underwent valvular surgery with del Nido cardioplegia (n=37) or HTK cardioplegia (n=34) were retrospectively analyzed. RESULTS: Patients' characteristics were comparable between groups. Postoperative peak troponin T levels were similar. The del Nido group had a decreased incidence of ventricular fibrillation after aortic cross-clamp removal (13.51 vs. 55.88%; P<0.001), lower total volume of cardioplegia administered (1,000 [1,000, 1,250] vs. 1,800 [1,500, 2,000] mL; P<0.001), shorter hospital stay (6 [5, 8] vs. 7 [6, 10] days; P=0.03), and less postoperative red cell transfusion (34.29 vs. 61.11%; P=0.024). There is no difference in aortic cross-clamping time, postoperative change in left ventricular ejection fraction, intensive care unit stay, duration of inotropic support, new onset of atrial fibrillation, in-hospital mortality, complications, and three-year overall survival rate. CONCLUSION: Lactated Ringer's-based del Nido cardioplegia can be safely used for valvular surgery with acceptable clinical outcomes compared to HTK cardioplegia.

Extracorporeal Membrane Oxygenation Uses in Refractory Cardiogenic Shock After Open-Heart Surgery.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) is the first-line therapy for temporary mechanical circulatory support allowing cardiac and pulmonary recovery or as a bridge to further therapeutic alternatives. The aim of this study was to report clinical outcomes in adult patients with refractory cardiac failure after open-heart surgery undergoing ECMO in a single center with an ECMO unit in Chile. METHODS: We retrospectively analyzed adults with refractory cardiac failure after open-heart surgery who required a venoarterial (VA) ECMO between 2016 and 2021. RESULTS: Of 16 patients with VA ECMO, 60% were men (n=10), 90% had hypertension (n=14), 69% had < 30% of left ventricular ejection fraction (n=11), and the mean European System for Cardiac Operative Risk Evaluation II score was 12 ± 11%. ECMO support with central cannulation accounts for 81% (n=13), and an intra-aortic balloon pump was used in nine patients (56%). The mean time of support was 4.7 ± 2.6 days (1.5 - 12 days). ECMO weaning was achieved in 88% of patients, and in-hospital mortality was 44% (n=7) after discharge. The freedom from all-cause mortality at one year of follow-up of the entire cohort was 38% (n=6). CONCLUSION: VA ECMO is now a well-known life-saving therapeutic option, but mortality and morbidity remain high. Implementation of an ECMO program with educational training is mandatory in order to find the proper balance between patient benefits, ethical considerations, and public health financial input in South America.

[Anatomy-physiology considerations for cardiogenic shock with right ventricular involvement].

Since the discovery of right ventricular infarction, interest in the characteristics of the right ventricle has been increasing. Right ventricular function is now known to be a predictor of mortality in different settings. The right ventricle is a low-pressure, high-compliance, high-volume chamber. To carry out its normal function, it is coupled to the pulmonary circulation and the left ventricle. In the face of acute changes in pressure, volume overload and ischemia, it dilates to adapt to its new load. Its manifestation may be ventricular dysfunction and/or failure that will progress to cardiogenic shock due to right ventricular involvement. Various entities may be the cause of acute dysfunction: right ventricular infarction (alterations in contractility due to ischemia) and high-risk pulmonary thromboembolism (increased afterload). Both share a similar ventricular pathophysiology and high mortality without treatment. Understanding anatomy and physiology, dysfunction and acute ventricular failure are important to define a convenient diagnosis and treatment oriented towards pathophysiology. In this first part, the anatomy and physiology, acute right ventricular dysfunction/failure and cardiogenic shock are taken into consideration, from the perspective of these two entities. In another paper, treatment aimed at cardiogenic shock due to right ventricular involvement will be reviewed.

Desde el conocimiento del infarto del ventrículo derecho, el interés por las características del ventrículo derecho ha sido cada vez mayor. Ahora se sabe que la función ventricular derecha es un predictor de mortalidad en diferentes contextos. El ventrículo derecho es una cavidad de baja presión, alta compliancia y alto volumen. Para llevar a cabo su función normal se encuentra acoplado a la circulación pulmonar y al ventrículo izquierdo. Ante alteraciones agudas de sobrecarga de presión, volumen e isquemia, se dilata para adaptarse a su nueva carga. Su manifestación puede ser disfunción o falla ventricular que progresará a choque cardiogénico por involucro del ventrículo derecho. Diversas entidades pueden ser la causa de la disfunción aguda: el infarto del ventrículo derecho (alteraciones de la contractilidad por isquemia) y la tromboembolia pulmonar de alto riesgo (aumento de la poscarga). Ambas comparten una fisiopatología ventricular similar y alta mortalidad sin tratamiento. Entender la anatomía fisiológica, la disfunción y la falla ventricular aguda es importante para definir un diagnóstico oportuno y un tratamiento orientado a la fisiopatología. En esta primera parte se toma en consideración la anatomía fisiológica y la disfunción/falla aguda ventricular derecha y su desenlace en el choque cardiogénico, desde la perspectiva de estas dos entidades. En otro trabajo se revisará el tratamiento orientado al choque cardiogénico por involucro ventricular derecho.

Assessment of Myocardial Function in Infants of Mothers with Gestational Diabetes Mellitus Using Deformation Imaging over the First Year of Age.

OBJECTIVE: To assess serial myocardial performance and pulmonary vascular resistance (PVR) in infants of mothers with gestational diabetes mellitus (GDM) over the first year of life. STUDY DESIGN: This was a prospective, observational study. Echocardiography was performed at birth, 6 months, and 1 year of age. Pulmonary artery acceleration time and left ventricular (LV) eccentricity index provided surrogate measurements of PVR. Biventricular function was assessed by tissue Doppler imaging and deformation analysis. RESULTS: Fifty infants of mothers with GDM were compared with 50 controls with no difference in gestation (38.9 ± 0.8 weeks vs 39.3 ± 0.9 weeks; P = .05) or birthweight (3.55 ± 0.49 kg vs 3.56 ± 0.41 kg; P = .95). At 1 year of age, the pulmonary artery acceleration time was lower (70 ± 11 vs 79 ± 10; P = .01) in the GDM group. LV global longitudinal strain (24.7 ± 1.9 vs 28.8 ± 1.8 %; P < .01), LV systolic strain rate (1.8 ± 0.2 vs 2.1 ± 0.3 1/s; P < .01), and RV free wall strain (31.1 ± 4.8 vs 34.6 ± 3.9 %; P < .01) were lower in the GDM cohort at 1 year of age (all P values adjusted for gestation, mode of delivery, and maternal body mass index). CONCLUSIONS: Our findings demonstrate higher indices of PVR and lower biventricular function in infants of mothers with GDM compared with controls at each time point assessed in this study over the first year of life.

A new perspective on an old method: gated SPECT imaging for left ventricular contractile function assessment.

The ejection fraction (LVEF) is a commonly used marker of left ventricular function. However, because it is strongly influenced by loading conditions, it can be inaccurate in representing cardiac contractility. We therefore evaluated a gated SPECT based tool to simultaneously assess preload, afterload, and contractility. Using gated SPECT-determined ventricular volumes and arterial tension measurements, we calculated ventricular and arterial elastance (Ev and Ea), as well as end-diastolic volumes, which are surrogates for contractility, afterload, and preload, respectively. We applied this protocol to 1462 consecutive patients and assessed the ventricular function in patients with and without myocardial infarction. The median LVEF was 68% (IQR 62-74%). Patients with infarction exhibited decreased contractility (ventricular elastance of 3 mmHg/ml vs. 6 mmHg/ml), compensated by an increase of preload (end-diastolic volume of 100 ml vs. 78 ml) and a decrease in afterload (arterial elastance of 1.8 mmHg/ml vs. 2.2 ml/mmHg). These interactions yielded a preserved ejection fraction in both groups. Gated SPECT-measured volumes were consistent with values reported in the literature. In addition, the combination of nuclear imaging and arterial tension measurement accounted for not only the ejection fraction but also the loading context, providing a more accurate representation of cardiac contractility.

Left Ventricular Function and Dimensions Are Altered Early in Infants Developing Brain Injury in the Setting of Neonatal Encephalopathy.

We evaluated the association between left cardiac 3-dimensional echocardiographic parameters and brain injury in a single-center prospective study of neonates with neonatal encephalopathy. On day 2 of life, neonates with brain injury had greater left ventricle end-diastolic and stroke volume but also greater peak global circumferential strain detected by 3-dimensional echocardiogram.

Influence of Isolated Resistance Exercise on Cardiac Remodeling, Myocardial Oxidative Stress, and Metabolism in Infarcted Rats.

INTRODUCTION: Exercise is an important therapeutic strategy for preventing and treating myocardial infarction (MI)-induced cardiac remodeling and heart failure. However, the myocardial effects of resistance exercise on infarcted hearts are not completely established. In this study, we investigated the effects of resistance exercise on structural, functional, and molecular cardiac alterations in infarcted rats. METHODS: Three months after MI induction or simulated surgery, Wistar rats were assigned into three groups: Sham (n = 14); MI (n = 9); and exercised MI (MI-Ex, n = 13). Exercised rats performed, 3 times a week for 12 weeks, four climbs on a ladder with progressive loads. Cardiac structure and left ventricle (LV) function were analyzed by echocardiogram. Myocyte diameters were evaluated in hematoxylin- and eosin-stained histological sections as the smallest distance between borders drawn across the nucleus. Myocardial energy metabolism, lipid hydroperoxide, malondialdehyde, protein carbonylation, and antioxidant enzyme activities were evaluated by spectrophotometry. Gene expressions of NADPH oxidase subunits were evaluated by RT-PCR. Statistical analyses were performed using ANOVA and Tukey or Kruskal-Wallis and Dunn's test. RESULTS: Mortality did not differ between the MI-Ex and MI groups. MI had dilated left atrium and LV, with LV systolic dysfunction. Exercise increased the maximum load-carrying capacity, with no changes in cardiac structure or LV function. Myocyte diameters were lower in MI than in Sham and MI-Ex. Lactate dehydrogenase and creatine kinase activity were lower in MI than in Sham. Citrate synthase and catalase activity were lower in MI and MI-Ex than in Sham. Lipid hydroperoxide concentration was lower in MI-Ex than in MI. Nox2 and p22phox gene expressions were higher in MI-Ex than in Sham. Gene expression of Nox4 was higher in MI and MI-Ex than in Sham, and p47phox was lower in MI than in Sham. CONCLUSION: Late resistance exercise was safe in infarcted rats. Resistance exercise improved maximum load-carrying capacity, reduced myocardial oxidative stress, and preserved myocardial metabolism, with no changes in cardiac structure or left ventricle function in infarcted rats.

Effects of Resistance Exercise on Slow-Twitch Soleus Muscle of Infarcted Rats.

Although current guidelines recommend resistance exercise in combination with aerobic training to increase muscle strength and prevent skeletal muscle loss during cardiac remodeling, its effects are not clear. In this study, we evaluated the effects of resistance training on cardiac remodeling and the soleus muscle in long-term myocardial infarction (MI) rats. METHODS: Three months after MI induction, male Wistar rats were assigned to Sham (n = 14), MI (n = 9), and resistance exercised MI (R-MI, n = 13) groups. The rats trained three times a week for 12 weeks on a climbing ladder. An echocardiogram was performed before and after training. Protein expression of the insulin-like growth factor (IGF)-1/protein kinase B (Akt)/rapamycin target complex (mTOR) pathway was analyzed by Western blot. RESULTS: Mortality rate was higher in MI than Sham; in the R-MI group, mortality rate was between that in MI and Sham and did not differ significantly from either group. Exercise increased maximal load capacity without changing cardiac structure and left ventricular function in infarcted rats. Infarction size did not differ between infarcted groups. Catalase activity was lower in MI than Sham and glutathione peroxidase lower in MI than Sham and R-MI. Protein expression of p70S6K was lower in MI than Sham and p-FoxO3 was lower in MI than Sham and R-MI. Energy metabolism did not differ between groups, except for higher phosphofrutokinase activity in R-MI than MI. CONCLUSION: Resistance exercise is safe and increases muscle strength regardless structural and functional cardiac changes in myocardial-infarcted rats. This exercise modality attenuates soleus glycolytic metabolism changes and improves the expression of proteins required for protein turnover and antioxidant response.

Protocol-based Surgical Intervention to Manage Ventricular Septal Rupture from a Tier Two City.

INTRODUCTION: This study analyzes the outcome of a protocol-based surgical approach for ventricular septal rupture (VSR). The study also clarifies the appropriate time for intervention. METHODS: This is a single-center retrospective analysis of all VSR cases evaluated between February 2006 and March 2020. Cases were managed using the same protocol. Patients were divided into two cohorts - early (those in whom our protocol was instituted within 24 hours of diagnosis) and delayed (intervention between 24 hours and seven days after diagnosis). All-cause mortality was considered as the outcome. RESULTS: The mean age of presentation was 60.1 years, and 75.9% of the patients were men. Cardiogenic shock was the most common mode of presentation. Our analysis validates that once a patient develops VSR, age, sex, comorbidities, left ventricular function, and renal failure at the time of presentation do not have a statistically significant impact on the outcome. The sole factor to have an impact on the outcome was time of intervention. All patients in the delayed cohort expired after surgery, which dragged the overall mortality to 34.5%, whereas 95% of patients in the early cohort are still on follow-up. The mortality in this group was 5% (P≤0.001). CONCLUSION: Early surgical intervention has proven benefits over delayed approach. Surgical intervention in the early part of the disease reduces the risk and thus improves the outcome. The extreme rarity makes VSR an uncommon entity among surgeons. A protocol-based approach makes the team adapt to this unfamiliar situation better.

Helical structure of the ventricular myocardium. A narrative review of cardiac mechanics.

To date, the ventricular myocardial band is the anatomical-functional model that best explains cardiac mechanics during systolic-diastolic phenomena in the cardiac cycle. The implications of the model fundamentally affect the anatomical interpretation of the ventricular myocardium, giving meaning to the direction that muscle fibers take, turning them into an object of study with potential clinical, imaging, and surgical applications. Re-interpreting the anatomy of the ventricular muscle justifies changes in the physiological interpretation, from its functional focus as a fiber unraveling the mechanical phenomena carried out during systole and diastole. We identify the functioning of the heart from the electrical and hemodynamic point of view, but it is necessary to delve into the mechanics that originate the hemodynamic changes observed flowmetrically, and that manifested during the pathology. In this review, the mechanical phenomena that the myocardium performs in each phase of the cardiac cycle are broken down in detail, emphasizing the physical displacements that each of the muscle segments presents, as well as a vision of their alteration and in which pathologies they are mainly identified. Visually, an anatomical correlation to the echocardiogram is provided, pointing out the direction of the segmental myocardial displacement by the strain velocity vector technique.

Left ventricular function by strain in uncomplicated malaria: a prospective study from the Brazilian Amazon.

We hypothesized that adults with uncomplicated malaria have lower left ventricular contractile function compared to the general population and that this improves after antimalarial treatment. We examined uncomplicated malaria and the general population from the Western part of the Brazilian Amazon Basin. All persons underwent an echocardiographic examination and peripheral blood smears. Left ventricular function was assessed by speckle tracking analysis of global longitudinal strain (GLS). Logistic regression models were used to assess the association between malaria status (yes/no) and GLS and improvement in GLS by follow-up was assessed using a paired T-test. We enrolled 99 adults with uncomplicated malaria (mean age 40 years, 46% female) of whom 75 had Plasmodium vivax, 22 Plasmodium falciparum and two had both species [median 1595 (528 to 6585) parasites/mm3]. Seventy adults completed a follow-up examination after standard malaria treatment (median 31 days). We examined 486 from the general population (mean age 41 years, 63% female). In persons with malaria at baseline, GLS was lower compared to the general population (18.7% vs. 19.4%, P = 0.002) and GLS improved at follow-up (19.2%, P = 0.032). In multivariable models adjusted for clinical, socioeconomic and echocardiographic confounders, baseline GLS remained significantly associated with malaria status [odds ratio 2.45 (95%CI 1.00 to 7.25), P = 0.023 per 1% increase]. Parasite density was associated with worsening in GLS [+ 16% (+ 0% to + 34%), P = 0.047 per 1 unit increase in GLS]. Adults with uncomplicated malaria had lower GLS compared to the general population and this improved after completed antimalarial treatment. Our results suggest that malaria infection may affect left ventricular contractile function, however, further studies are needed to fully elucidate such a relationship.

Cardiomyopathy Induced by Artificial Cardiac Pacing: To Whom, When, Why, and How? Insights on Heart Failure Development.

Coordinated and harmonic (synchronous) ventricular electrical activation is essential for better left ventricular systolic function. Intraventricular conduction abnormalities, such as left bundle branch block due to artificial cardiac pacing, lead to electromechanical "dyssynchronopathy" with deleterious structural and clinical consequences. The aim of this review was to describe and improve the understanding of all the processes connecting the several mechanisms involved in the development of artificially induced ventricular dyssynchrony by cardiac pacing, most known as pacing-induced cardiomyopathy (PiCM). The chronic effect of abnormal impulse conduction and nonphysiological ectopic activation by artificial cardiac pacing is suspected to affect metabolism and myocardial perfusion, triggering regional differences in the activation/contraction processes that cause electrical and structural remodeling due to damage, inflammation, and fibrosis of the cardiac tissue. The effect of artificial cardiac pacing on ventricular function and structure can be multifactorial, and biological factors underlying PiCM could affect the time and probability of developing the condition. PiCM has not been included in the traditional classification of cardiomyopathies, which can hinder detection. This article reviews the available evidence for pacing-induced cardiovascular disease, the current understanding of its pathophysiology, and reinforces the adverse effects of right ventricular pacing, especially right ventricular pacing burden (commonly measured in percentage) and its repercussion on ventricular contraction (reflected by the impact on left ventricular systolic function). These effects might be the main defining criteria and determining mechanisms of the pathophysiology and the clinical repercussion seen on patients.