Mechanical dispersion is a superior echocardiographic feature to predict exercise capacity in preclinical and overt heart failure with preserved ejection fraction.

BACKGROUND: Heart Failure with Preserved Ejection Fraction (HFpEF) is a syndrome characterized by different degrees of exercise intolerance, which leads to poor quality of life and prognosis. Recently, the European score (HFA-PEFF) was proposed to standardize the diagnosis of HFpEF. Even though Global Longitudinal Strain (GLS) is a component of HFA-PEFF, the role of other strain parameters, such as Mechanical Dispersion (MD), has yet to be studied. In this study, we aimed to compare MD and other features from the HFA-PEFF according to their association with exercise capacity in an outpatient population of subjects at risk or suspected HFpEF. METHODS: This is a single-center cross-sectional study performed in an outpatient population of 144 subjects with a median age of 57 years, 58% females, referred to the Echocardiography and Cardiopulmonary Exercise Test to investigate HFpEF. RESULTS: MD had a higher correlation to Peak VO2 (r=-0.43) when compared to GLS (r=-0.26), MD presented a significant correlation to Ventilatory Anaerobic Threshold (VAT) (r=-0.20; p = 0.04), while GLS showed no correlation (r=-0.14; p = 0.15). Neither MD nor GLS showed a correlation with the time to recover VO2 after exercise (T1/2). In Receiver Operator Characteristic (ROC) analysis, MD presented superior performance to GLS to predict Peak VO2 (AUC: 0.77 vs. 0.62), VAT (AUC: 0.61 vs. 0.57), and T1/2 (AUC: 0.64 vs. 0.57). Adding MD to HFA-PEFF improved the model performance (AUC from 0.77 to 0.81). CONCLUSION: MD presented a higher association with Peak VO2 when compared to GLS and most features from the HFA-PEFF. Adding MD to the HFA-PEFF improved the model performance.

Afterload increase challenge unmasks systolic abnormalities in heart failure with preserved ejection fraction.

BACKGROUND: Provocative maneuvers have the potential to overcome the low sensitivity of resting echocardiography and biomarkers in the detection of heart failure with preserved ejection fraction (HFpEF). We investigate the mechanical response of the left ventricle to an afterload challenge in patients with preclinical and early-stage HFpEF (es-HFpEF). METHODS: Three groups of patients (non-HFpEF - n = 42, pre-HFpEF - n = 43, and es-HFpEF - n = 39) underwent echocardiography at rest and during an afterload challenge induced by handgrip maneuver combined with pneumatic constriction of limbs. RESULTS: Patients in the non-HF group displayed a median ΔLPSS = -4% (IQR: -10%, +2%), LPSS rest<16% in 3/42(7%) and LPSS stress<16% in 6/43(14%). Subjects in the pre-HFpEF group displayed median ΔLPSS = -3% (IQR: -10%, +5%) LPSS rest<16% in 13/43(30%) and LPSS stress<16% in 19/43 (44%). 11/43 (25%) subjects in this group increased at least one absolute point in LPSS during stress. Patients in es-HFpEF group displayed a median ΔLPSS = -10% (IQR: -18%, -1%), LPSS rest<16% in 15/39(38%) and LPSS stress<16% in 25/39(64%). Changes in LPSS (ΔLPSS) were significantly greater in es-HFpEF than pre-HFpEF (p = 0.022). In multivariate analysis, this group effect was maintained after adjustment of the LPSS for systolic blood pressure, use of ß-blockers, LV mass, RWT, age, and sex. CONCLUSION: Our data suggest that patients with HFpEF have a marked decrease in peak strain during acute pressure overload. Longitudinal studies are needed to test and compare the clinical impact of each pattern in early and long-term follow-ups.

Longitudinal study comparing IgG antibodies induced by heterologous prime-boost COVID-19 vaccine.

Vaccines are critical cost-effective tools to control the COVID-19 pandemic. The heterologous prime-boost vaccination has been used by many countries to overcome supply issues, so the effectiveness and safety of this strategy need to be better clarified. This study aims to verify the effect of heterologous prime-boost COVID-19 vaccination on healthcare professionals from Dante Pazzanese Hospital in Brazil. It was performed serological assays of vaccinated individuals after 2-dose of CoronaVac (Sinovac; n = 89) or ChAdOx1 nCoV-19 (Oxford-AstraZeneca; n = 166) followed by a BNT162b2 booster (Pfizer-BioNTech; n = 255). The serum antibodies anti-S (spike), anti-N (nucleocapsid), and anti-RBD (receptor binding domain) were assessed by enzyme-linked immunosorbent assay. The heterologous booster dose induced a 10-fold higher anti-Spike antibody regardless of the 2-dose of a prime vaccine. It was strikingly observed that BNT162b2 enhanced levels of anti-spike antibodies, even in those individuals who did not previously respond to the 2-dose of CoronaVac. In conclusion, the heterologous scheme of vaccination using mRNA as a booster vaccine efficiently enhanced the antibody response against SARS-CoV-2, especially benefiting those elderly who were seronegative with a virus-inactivated vaccine.

Sequential IgG antibody monitoring for virus-inactivated and adenovirus-vectored COVID-19 vaccine in Brazilian healthcare workers.

Vaccination certainly is the best way to fight against the COVID-19 pandemic. In this study, the seroconversion effectiveness of two vaccines against severe acute respiratory syndrome coronavirus 2 was assessed in healthcare workers: virus-inactivated CoronaVac (CV, n = 303), and adenovirus-vectored Oxford-AstraZeneca (AZ, n = 447). The immunoglobulin G (IgG) antibodies anti-spike glycoprotein and anti-nucleocapsid protein were assessed by enzyme-linked immunosorbent assay at the time before vaccination (T1), before the second dose (T2), and 30 days after the second dose (T3). Of all individuals vaccinated with AZ, 100% (n = 447) exhibited seroconversion, compared to 91% (n = 276) that were given CV vaccine. Among individuals who did not respond to the CV, only three individuals showed a significant increase in the antibody level 4 months later the booster dose. A lower seroconversion rate was observed in elders immunized with the CV vaccine probably due to the natural immune senescence, or peculiarity of this vaccine. The AZ vaccine induced a higher humoral response; however, more common side effects were also observed. Nonvaccinated convalescent individuals revealed a similar rate of anti-spike IgG to individuals that were given two doses of CV vaccine, which suggests that only a one-shot COVID-19 vaccine could produce an effective immune response in convalescents.

Serological Testing for COVID-19, Immunological Surveillance, and Exploration of Protective Antibodies.

Serological testing is a powerful tool in epidemiological studies for understanding viral circulation and assessing the effectiveness of virus control measures, as is the case of SARS-CoV-2, the pathogenic agent of COVID-19. Immunoassays can quantitatively reveal the concentration of antiviral antibodies. The assessment of antiviral antibody titers may provide information on virus exposure, and changes in IgG levels are also indicative of a reduction in viral circulation. In this work, we describe a serological study for the evaluation of antiviral IgG and IgM antibodies and their correlation with antiviral activity. The serological assay for IgG detection used two SARS-CoV-2 proteins as antigens, the nucleocapsid N protein and the 3CL protease. Cross-reactivity tests in animals have shown high selectivity for detection of antiviral antibodies, using both the N and 3CL antigens. Using samples of human serum from individuals previously diagnosed by PCR for COVID-19, we observed high sensitivity of the ELISA assay. Serological results with human samples also suggest that the combination of higher titers of antiviral IgG antibodies to different antigen targets may be associated with greater neutralization activity, which can be enhanced in the presence of antiviral IgM antibodies.

Late Outcomes of Aortic Valve Replacement with Bioprosthesis and Mechanical Prosthesis. / Evolução Tardia das Próteses Biológicas e Mecânicas em Posição Aórtica.

BACKGROUND: Despite constant improvement and refinement of the prostheses, the decision between mechanical and biological valves for aortic valve replacement is still controversial. OBJECTIVE: To compare outcomes of aortic valve replacement with bioprosthesis and mechanical prosthesis. METHODS: This was an observational, historical cohort study with review of medical records. A total of 202 patients who underwent heart valve replacement surgery between 2004 and 2008 were selected, with a mean follow-up of 10 years. The level of significance set at 5%. RESULTS: Mean age of patients was approximately 50 years; most patients were male (70%). Overall mortality- and reoperation-free survival was significantly higher in patients with mechanical prosthesis (HR=0.33; 95%CI=0.13-0.79; p=0.013). No difference was found in late mortality between the two groups. On the other hand, the risk of reoperation was significantly higher in patients with bioprosthesis than mechanical prosthesis (HR=0.062; 95%CI=0.008-0.457; p=0.006). The risk of composite adverse events - stroke, bleeding, endocarditis, thrombosis and paravalvular leak - was similar between the groups (HR=1.20; 95%CI= 0.74-1.93; p=0.44). The risk of bleeding was significantly higher in patients with mechanical prosthesis (HR=3.65; 95%CI= 1.43-9.29; p = 0.0064), although no case of fatal bleeding was reported. CONCLUSION: No difference in 10-year mortality was found between the groups. The risk of reoperation significantly increases with the use of bioprosthesis, especially for patients younger than 30 years. Patients with mechanical prosthesis are at increased risk of nonfatal bleeding.

FUNDAMENTO: Apesar da constante renovação e do aprimoramento das próteses valvares cardíacas, a decisão sobre substituição por prótese biológica ou mecânica permanece controversa. OBJETIVO: Comparar pacientes submetidos à cirurgia para troca valvar aórtica utilizando substituto biológico ou mecânico. MÉTODOS: Estudo observacional, do tipo coorte histórica por análise de prontuário. Foram selecionados 202 operados entre 2004 e 2008, com seguimento médio de 10 anos. O nível de significância estatística adotado foi de 5%. RESULTADOS: A média de idade foi de aproximadamente 50 anos para ambos os grupos, com a maioria (70%) do sexo masculino. A probabilidade de sobrevida livre de óbito e reoperação foi significativamente maior nos pacientes com prótese mecânica (HR=0,33; IC 95%=0,13-0,79; p=0,013). Não houve diferença entre os grupos em relação à mortalidade tardia. Por outro lado, o risco de reoperação foi significativamente maior em pacientes tratados com prótese biológica em comparação com a prótese mecânica (HR=0,062; IC 95%=0,008-0,457; p=0,006). O risco de eventos adversos composto de acidente vascular encefálico (AVE), sangramento, endocardite, trombose e regurgitação paraprotética foi semelhante entre os grupos (HR=1,20; IC 95%=0,74-1,93; p=0,44). O risco de sangramento foi significativamente maior em pacientes tratados com prótese mecânica (HR=3,65; IC 95%=1,43-9,29; p=0,0064), porém não houve sangramento fatal. CONCLUSÃO: Não há diferença de mortalidade em 10 anos entre os dois grupos. Há aumento significativo no risco de reoperação ao se optar por próteses biológicas, principalmente para os menores de 30 anos de idade. Já os pacientes portadores de prótese mecânica têm maior risco de sangramento não fatal.

Oxygen supplementation increases the total work and muscle damage markers but reduces the inflammatory response in COPD patients.

INTRODUCTION: Oxygen supplementation (O2-Suppl) is recommended for pulmonary rehabilitation with higher exercise intensities. However, high-intensity exercise tends toward muscle damage and a greater inflammatory response. We aimed to investigate the effect of O2-Suppl during exercise test (EET) on CRP level and muscle damage (CPK, LDH, lactate) in non-hypoxemic COPD patients. METHODS: Eleven non-depleted patients with COPD (FEV1 65.5 ± 4.3 %) performed two EET (room-air or O2-Suppl-100 %), through a blind, randomized, and placebo-controlled crossover design. CPK, LDH and CRP were measured before, immediately after and 24 h after EET. RESULTS: Exercise time was higher with O2-Suppl (49.9 ± 37.3 %; p = 0.001) and increases in CPK and LDH were observed compared to basal values in the O2-Suppl (28.4UI/L and 28.3 UI/L). The O2-Suppl protocol resulted in a lower increase in CRP (92.1 ± 112.4 % vs. 400.1 ± 384.9 %; p = 0.003). CONCLUSIONS: O2-Suppl increases exercise-tolerance, resulting in increased muscle injury markers in COPD. However, oxygen supplementation attenuates the inflammatory response, even upon increased physical exercise.

Cardiology Training in Brazil and Developed Countries: Some Ideas for Improvement.

Huge variations exist in cardiology training programs across the world. In developing (middle-income) countries, such as Brazil, to find the right balance between training improvements and social and economic conditions of the country may be a difficult task. Adding more training years or different mandatory rotations, for instance, may be costly and not have an immediate direct impact on enhancing patient care or public health. In this text, we compare the Brazilian cardiology training system with other proposals implemented in developed countries from North America and Europe, aiming to point out issues worth of future discussion. Factors such as training rotations and competencies, and program duration and distribution across the countries are presented. The number of first year cardiology trainees per inhabitants is similar between Brazil and the United States (0.24 medical residents/100,000 inhabitants in Brazil and 0.26 medical residents/100,000 inhabitants in the USA). These numbers should be analyzed considering the inequality in training program distribution across Brazil, since most centers are located in the Southeast and South regions. Having more residency programs in distant areas could improve cardiovascular care in these areas. Duration of cardiology Residency Training is shorter in Brazil (two years) in comparison with developed countries (> 3 years). Brazilian residency programs give less emphasis to scientific research and diagnostic methods. Unifying minimum training requirements across the globe would facilitate the development of international learning opportunities and even professional exchange around the world.

Cardiology training in Brazil and developed countries: some ideas for improvement / Residência em cardiologia no Brasil e em países desenvolvidos: ideias para melhoria

ABSTRACT: Huge variations exist in cardiology training programs across the world. In developing (middle-income) countries, such as Brazil, to find the right balance between training improvements and social and economic conditions of the country may be a difficult task. Adding more training years or different mandatory rotations, for instance, may be costly and not have an immediate direct impact on enhancing patient care or public health. In this text, we compare the Brazilian cardiology training system with other proposals implemented in developed countries from North America and Europe, aiming to point out issues worth of future discussion. Factors such as training rotations and competencies, and program duration and distribution across the countries are presented. The number of first year cardiology trainees per inhabitants is similar between Brazil and the United States (0.24 medical residents/100,000 inhabitants in Brazil and 0.26 medical residents/100,000 inhabitants in the USA). These numbers should be analyzed considering the inequality in training program distribution across Brazil, since most centers are located in the Southeast and South regions. Having more residency programs in distant areas could improve cardiovascular care in these areas. Duration of cardiology Residency Training is shorter in Brazil (two years) in comparison with developed countries (> 3 years). Brazilian residency programs give less emphasis to scientific research and diagnostic methods. Unifying minimum training requirements across the globe would facilitate the development of international learning opportunities and even professional exchange around the world.

RESUMO: Existe enorme variação nos programas de residência em cardiologia no mundo. Em países em desenvolvimento, tal como o Brasil, encontrar o equilíbrio correto entre melhorias nos programas de residência e condições socioeconômicas do país pode ser uma tarefa difícil. Aumentar a duração dos programas ou o número de estágios obrigatórios, por exemplo, pode ter um custo elevado e não ter um impacto imediato na melhoria do cuidado do paciente ou na saúde pública. Neste texto, comparamos o sistema de residência em cardiologia brasileiro com outras propostas implementadas em países desenvolvidos da América do Norte e Europa, com objetivo de indicar questões para discussões futuras. Apresentamos fatores como rodízios por estágios e competências, duração e distribuição dos programas pelos países. O número de alunos no primeiro ano de Residência em cardiologia por número de habitantes é similar entre o Brasil e os Estados Unidos (0,24 médicos residentes/100 mil habitantes no Brasil e 0,26 médicos residentes/100 mil habitantes nos EUA). Esses números devem ser analisados considerando a desigualdade na distribuição dos programas pelo país, uma vez que a maioria dos centros localiza-se nas regiões sul e sudeste do país. A existência de mais programas de residência em áreas distantes melhoraria o cuidado cardiovascular nessas áreas. O período de treinamento é menor no Brasil (dois anos) em comparação a países desenvolvidos (>3 anos). Os programas de residência no Brasil dão menos ênfase em pesquisa científica e métodos diagnósticos. O estabelecimento de exigências mínimas que sejam padronizadas a todos os países facilitaria o desenvolvimento de oportunidades de aprendizagem e mesmo o intercâmbio de profissionais pelo mundo.

Heart rate recovery improvement in patients following acute myocardial infarction: exercise training, ß-blocker therapy or both.

Heart rate recovery (HRR) is a strong mortality predictor. Exercise training (ET) and ß-blocker therapy have significant impact on the HRR of patients following myocardial infarction (MI). However, the combination of ET and ß-blocker therapy, as well as its effectiveness in patients with a more compromised HRR (≤12 bpm), has been under-studied. Male patients (n = 64) post-MI were divided: Training + ß-blocker (n = 19), Training (n = 15), ß-blocker (n = 11) and Control (n = 19). Participants performed an ergometric test before and after 3 months of intervention. HRR was obtained during 5 min of recovery and corrected by the cardiac reserve (HRRcorrCR ). Compared to pre-intervention, HRRcorrCR was significantly increased during the 1st and 2nd minutes of recovery in the Training + ß-blocker group (70·5% and 37·5%, respectively; P<0·05). A significant improvement, lasting from the 1st to the 4th minute of recovery, was also observed in the Training group (47%, 50%, 25% and 8·7%, respectively; P<0·05). In contrast, the ß-blocker group showed a reduction in HRRcorrCR during the 2nd and 3rd minutes of recovery (-21·2% and -16·3%, respectively; P<0·05). In addition, interventions involving ET (Training + ßb, Training) were significantly more effective in patients with a pre-intervention HRR ≤ 12 bpm than for patients with HRR > 12 bpm. Combination of ß-blocker therapy with ET does not compromise the effect of training and instead promotes HRR and aerobic capacity improvement. In addition, this combination is particularly beneficial for individuals presenting with a more compromised HRR. However, chronic administration of ß-blocker therapy alone did not promote improvement in HRR or aerobic capacity.

Analysis of Circulating miR-1, miR-23a, and miR-26a in Atrial Fibrillation Patients Undergoing Coronary Bypass Artery Grafting Surgery.

Atrial fibrillation (AF) is the most common arrhythmia after cardiac surgery. From a pathophysiological point of view, a myriad of factors such as trauma, atrial dilation, ischemia, mechanical myopericarditis, autonomic imbalance, loss of connexins, AF nest remodeling, inflammation, sutures, and dysfunction caused by postextracorporeal circulation can contribute to postoperative atrial fibrillation (POAF) resulting in a longer hospital stay and consequently higher cost. Recent studies showed that short fragments of RNA, called microRNA (miRNA), can contribute to the development of several cardiovascular diseases, including AF. The aim of this study was to evaluate the levels of circulating miRNAs (miR-1, -23a, and -26a) that can be involved in POAF. Patients submitted to coronary artery bypass graft surgery were grouped in POAF (24 patients) and without POAF (24 patients). Results showed older age, longer clamp-time, and more days in the intensive care unit as well as a longer total hospital stay in the POAF group. Preoperative levels of circulating miRNAs were similar. Analysis of miRNAs revealed significantly lower circulating levels of miRNA-23a (P = 0.02) and -26a (P = 0.01) in the POAF group during the postoperative period. Receiver operating characteristic (ROC) analysis showed the area under the ROC curve of miR-23a and miR-26a for predicting FA was 0.63 (95% confidence interval [CI]: 0.51-0.74; P = 0.02) and 0.66 (95% CI: 0.55-0.77; P = 0.01), respectively. Our data suggests that circulating miRNA-23a and -26a may be involved in the underlying biology of postoperative AF development.

Hemodynamics and tissue oxygenation effects after increased in positive end-expiratory pressure in coronary artery bypass surgery.

BACKGROUND: Cardiac surgery is widely used in the treatment of cardiovascular diseases. However, several complications can be observed during the postoperative period. Positive end expiratory pressure (PEEP) improves gas exchange, but it might be related to decreased cardiac output and possible impairment of tissue oxygenation. The aim of this study was to investigate the hemodynamic effects and oxygen saturation of central venous blood (ScvO2) after increasing PEEP in hypoxemic patients after coronary artery bypass (CAB) surgery. METHODS: Seventy post-cardiac surgery patients (CAB), 61 ± 7 years, without ventricular dysfunction (left ventricular ejection fraction 57 ± 2%), with hypoxemia (PaO2/FiO2 ratio <200) were enrolled. Heart rate, mean arterial pressure, arterial and venous blood samples were measured at intensive care unit and PEEP was increased to 12 cmH2O for 30 min. RESULTS: As expected, PEEP12 improved arterial oxygenation and PaO2/FiO2 ratio (p < 0.0001). Reduction in ScvO2 was observed between PEEP5 (63 ± 2%) and PEEP12 (57 ± 1%; p = 0.01) with higher values of blood lactate in PEEP12 (p < 0.01). No hemodynamic effects (heart rate, mean arterial pressure, SpO2; p > 0.05) were related. CONCLUSION: Increased PEEP after cardiac surgery decreased ScvO2 and increased blood lactate, even with higher O2 delivery. PEEP did not interfere in hemodynamics status in CAB patients, suggesting that peripheral parameters must be controlled and measured during procedures involving increased PEEP in post-cardiac surgery patients in the intensive care unit.

The dysfunction of ammonia in heart failure increases with an increase in the intensity of resistance exercise, even with the use of appropriate drug therapy.

BACKGROUND: Hyperammonemia during rest periods is a dysfunction in heart failure (HF). The low formation of ammonia during exercise reflects an inefficiency of purine metabolism. Hyperkalemia in response to physical exercise is common in HF and may contribute to a contractile inefficiency in type II fibers, leading to early fatigue. We tested the hypothesis that during resistance exercise of high intensity and low volume, this disorder of ammonia metabolism would be more intense, due to the hyperkalemia present in HF. METHODS: Alternating resistance exercise (RE) of low intensity and high volume, and high intensity and low volume, were applied to 18 patients with an interval of 7 days between them (functional class II-III New York Heart Association, FE = 33.5 ± 4%) and compared with 22 healthy controls matched for age and gender. Ammonia, potassium and lactate levels were assessed before and immediately after the RE. RESULTS: Significant differences: Deltas (control vs. HF) in 40% RE: lactate (mg/dl) 26.3 ± 10 vs. 37.7 ± 7; p < 0,001, ammonia (ug/dl) 92.5 ± 18 vs. 48.9 ± 9; p < 0.001. Deltas (control vs. HF) in 80%RE: lactate(mg/dl) 45.0 ± 12 vs. 54.1 ± 11; p < 0.05, ammonia(ug/dl) 133.5 ± 22 vs. 32.2 ± 7; p < 0.001, potassium (mEq/L) 1.6 ± 0.4 vs. 2.0 ± 0.8; p < 0.05. A negative correlation was found between the deltas of ammonia and potassium (r = -0.74, p < 0.001) in the HF group. CONCLUSIONS: We conclude that in HF, there is an inefficiency of purine metabolism that increases with increasing exercise intensity, but not with an increase of total volume. These findings suggest that hyperkalemia may play an important role in the disorders of purine metabolism.

Myocardial protection with prophylactic oral metoprolol during coronary artery bypass grafting surgery: evaluation by troponin I / Proteção cardíaca com uso profilático de betabloqueador oral em cirurgia de revascularização miocárdica: avaliação pela troponina I

INTRODUCTION: Biochemical markers of myocardial injury are frequently altered after cardiac surgery. So far there is no evidence whether oral beta-blockers may reduce myocardial injury after coronary artery bypass grafting. OBJECTIVE: To determine if oral administration of prophylactic metoprolol reduces the release of cardiac troponin I in isolated coronary artery bypass grafting, not complicated by new Q waves. METHODS: A prospective randomized study, including 68 patients, divided in 2 groups: Group A (n=33, control) and B (n=35, beta-blockers). In group B, metoprolol tartrate was administered 200 mg/day. The myocardial injury was assessed by troponin I with 1 hour and 12 hours after coronary artery bypass grafting. RESULTS: No significant difference between groups regarding pre-surgical, surgical, complication in intensive care (15% versus 14%, P=0.92) and the total number of hospital events (21% versus 14%, P=0.45) was observed. The median value of troponin I with 12 hours in the study population was 3.3 ng/ml and was lower in group B than in group A (2.5 ng/ml versus 3.7 ng/ml, P<0,05). In the multivariate analysis, the variables that have shown to be independent predictors of troponin I release after 12 hours were: no beta-blockers administration and number of vessels treated. CONCLUSION: The results of this study in uncomplicated coronary artery bypass grafting, comparing the postoperative release of troponin I at 12 hours between the control group and who used oral prophylactic metoprolol for at least 72 hours, allow to conclude that there was less myocardial injury in the betablocker group, giving some degree of myocardial protection.

INTRODUÇÃO: Os marcadores bioquímicos de lesão miocárdica estão frequentemente alterados após cirurgia cardíaca. Até o momento não existem evidências de que o betabloqueador oral possa reduzir a lesão miocárdica após cirurgia de revascularização miocárdica. OBJETIVO: Determinar se a administração oral profilática de metoprolol reduz a liberação de troponina cardíaca I na cirurgia de revascularização miocárdica isolada não complicada por novas ondas Q. MÉTODOS: Estudo prospectivo, randomizado, incluindo 68 pacientes divididos em 2 grupos: Grupo A (n=33, controle) e B (n=35, betabloqueador). No grupo B, o tartarato de metoprolol foi administrado na dose de 200 mg/dia. A lesão miocárdica foi avaliada pela troponina I com 1 hora e 12 horas após a cirurgia de revascularização miocárdica. RESULTADOS: Não foi observada diferença significativa entre os grupos quanto às variáveis pré-cirúrgicas, cirúrgicas, incidência de complicações na terapia intensiva (15% versus 14%; P=0,92) e o número total de eventos hospitalares (21% versus 14%; P=0,45). O valor da mediana da troponina I com 12 horas na população estudada foi de 3,3 ng/ml e foi menor no grupo B do que no grupo A (2,5 ng/ml versus 3,7 ng/ml; P<0,05). Na análise multivariada, as variáveis que demonstraram serem preditoras independentes da liberação de troponina cardíaca I com 12 horas foram: não uso de betabloqueadores e número de vasos tratados. CONCLUSÃO: Os resultados desta investigação na cirurgia de revascularização miocárdica isolada, não complicada, comparando a liberação pós-operatória de troponina cardíaca I com 12 horas entre os grupos controle e o que usou metoprolol oral profilático por pelo menos 72 horas, permitem concluir que houve menor lesão miocárdica no grupo betabloqueador, conferindo algum grau de proteção miocárdica.

Aplicabilidade do peso ideal na titulação do volume corrente em pacientes no pós-operatório imediato de cirurgia cardíaca / Applicability of ideal weight in the titration of the flow volume in immediate postoperative cardiac surgery patients

Introdução: A ventilação mecânica (VM) é indispensável nas intervençõescirúrgicas cardíacas. Porém, mesmo que por curto períodode tempo, pode causar prejuízo pulmonar, com lesões no parênquimapor excesso de pressão e/ou volume nas vias aéreas. Na titulação dovolume corrente (VC), é comum utilizar o peso real e não o pesoideal, aquele calculado baseando-se pela altura, o que poderia geraralterações gasométricas e na mecânica pulmonar. Objetivo: Comparara titulação do volume corrente pelo peso ideal e pelo peso realdurante o uso da VM no pós-operatório imediato de cirurgia cardíaca.Método: Ensaio clínico prospectivo, randomizado, realizado no períodode agosto a novembro de 2008. Pacientes de ambos os gêneros,idade entre 18 e 80 anos foram randomizados em dois grupos: peso real(PR) e peso ideal (PI) durante o pós-operatório imediato de cirurgiacardíaca, nos quais foram analisados a troca gasosa, pela gasometriarealizada no ato de admissão e 30 minutos após a mesma; e a mecânicapulmonar (pressão platô). Pacientes com acidose metabólicacom pH < 7,2 foram excluídos. A análise estatística incluiu teste denormalidade de Kolmogorov-Smirnov, teste t com p < 0,05, e testede Mann Whitney para variáveis não paramétricas. Resultados: Totalde 55 pacientes, sendo 28 no grupo PR e 25 no PI; dois pacientesexcluídos, restando 29 homens e 24 mulheres. A idade média foi de58,83 ± 11,74 anos. Os valores de pressão platô (PR: 19,29 cmH2Ovs PI: 17,12 cmH2O), pH (PR: 7,38 vs. PI: 7,32) e PCO2 (PR: 34,5mmHg vs. PI: 40,85 mmHg) foram estatisticamente significantes,com p < 0,04, p < 0,01 e p < 0,02, respectivamente. Conclusão: Usodo PR pareceu ser benéfico na população estudada quando analisadodistúrbio ácido básico; porém, o grupo PI mostrou-se melhor quantoà mecânica pulmonar.

Introduction: The mechanical ventilation (MV) is essential in cardiacsurgery. But even for a short period of time, the MV can causelung injury with parenchyma injury of pressure and/or volume inthe airways. In the titration of tidal it is common to use the actualweight rather than the ideal weight, calculated based on the height,which could generate gasometric and changes in lung mechanics.Objective: To compare the titration of the current volume by idealweight and the actual weight during the use of MV in the immediatepostoperative period of cardiac surgery. Method: Clinical prospective,randomized, carried out from August to November 2008. Patientsof both sexes, aged between 18 and 80 years, randomized into twogroups: actual weight (AW) and ideal weight (IW), in the immediatepostoperative period of cardiac surgery. The blood gas analysis wasconducted in the act of admission and 30 minutes after that. Blood gasand pressure plateau results were compared among the two groups.Patients with metabolic acidosis of pH < 7.2 were excluded. Statisticalanalysis included the test of Kolmogorov-Smirnov normality, t testwith p < 0.05, and the Mann Whitney test for non parametric variables.Results: Total 55 patients being 28 PR and 25 IP, 2 excludedpatients, 29 men and 24 women. The average age was 58.83 ± 11.74years. The values of Plateau pressure (real: 19.29 vs ideal: 17.12), pH(real: 7.38 vs ideal: 7.32) and PCO2 (real: 34.5 vs ideal: 40.85) werestatistically significant, with p < 0.04, p < 0.01 and p < 0.02, respectively.Conclusion: Using the actual weight seemed to be beneficialin the study population as compared to the ideal weight when disturbacid basic was analyzed.

Myocardial protection with prophylactic oral metoprolol during coronary artery bypass grafting surgery: evaluation by troponin I.

INTRODUCTION: Biochemical markers of myocardial injury are frequently altered after cardiac surgery. So far there is no evidence whether oral beta-blockers may reduce myocardial injury after coronary artery bypass grafting. OBJECTIVE: To determine if oral administration of prophylactic metoprolol reduces the release of cardiac troponin I in isolated coronary artery bypass grafting, not complicated by new Q waves. METHODS: A prospective randomized study, including 68 patients, divided in 2 groups: Group A (n=33, control) and B (n=35, beta-blockers). In group B, metoprolol tartrate was administered 200 mg/day. The myocardial injury was assessed by troponin I with 1 hour and 12 hours after coronary artery bypass grafting. RESULTS: No significant difference between groups regarding pre-surgical, surgical, complication in intensive care (15% versus 14%, P=0.92) and the total number of hospital events (21% versus 14%, P=0.45) was observed. The median value of troponin I with 12 hours in the study population was 3.3 ng/ml and was lower in group B than in group A (2.5 ng/ml versus 3.7 ng/ml, P<0,05). In the multivariate analysis, the variables that have shown to be independent predictors of troponin I release after 12 hours were: no beta-blockers administration and number of vessels treated. CONCLUSION: The results of this study in uncomplicated coronary artery bypass grafting, comparing the postoperative release of troponin I at 12 hours between the control group and who used oral prophylactic metoprolol for at least 72 hours, allow to conclude that there was less myocardial injury in the betablocker group, giving some degree of myocardial protection.

Effect of a physical exercise program in a patient with Marfan syndrome and ventricular dysfunction.

Marfan syndrome (MS) is an autosomal dominant disorder that affects multiple organs and systems. Several cardiac alterations are present, with the main ones being aortic root and ascending aorta dilatation, mitral valve prolapse and left ventricle (LV) dilatation. Aerobic exercise has not shown to be a non-drug therapy that promotes anti-remodeling effect in patients with heart failure. This case report describes the echocardiographic changes in a patient with Marfan syndrome during four years of cardiovascular physical therapy.

Efeito de um programa de exercício físico em portador da Síndrome Marfan com disfunção ventricular / Effect of a physical exercise program in a patient with Marfan Syndrome and ventricular dysfunction / Efecto de un programa de ejercicio físico en portador del Síndrome Marfan con disfunción ventricular

A Síndrome de Marfan (SM) é uma desordem autossômica dominante que afeta múltiplos órgãos e sistemas. Diversas alterações cardíacas estão presentes, sendo as principais a dilatação da raiz da aorta e da aorta ascendente, o Prolapso de Valva Mitral e a dilatação do Ventrículo Esquerdo (VE). O exercício aeróbico tem-se mostrado um recurso terapêutico não medicamentoso, por promover efeito de antirremodelamento em pacientes com insuficiência cardíaca. Este relato de caso descreve as alterações ecocardiográficas de um paciente com Síndrome de Marfan durante quatro anos de um programa de fisioterapia cardiovascular.

Marfan syndrome (MS) is an autosomal dominant disorder that affects multiple organs and systems. Several cardiac alterations are present, with the main ones being aortic root and ascending aorta dilatation, mitral valve prolapse and left ventricle (LV) dilatation. Aerobic exercise has not shown to be a non-drug therapy that promotes anti-remodeling effect in patients with heart failure. This case report describes the echocardiographic changes in a patient with Marfan syndrome during four years of cardiovascular physical therapy.

El Síndrome de Marfan (SM) es un desorden autosómico dominante que afecta múltiples órganos y sistemas. Diversas alteraciones cardíacas están presentes, siendo las principales la dilatación de la raíz de la aorta y de la aorta ascendente, el Prolapso de Válvula Mitral y la dilatación del Ventrículo Izquierdo (VI). El ejercicio aeróbico ha mostrado ser un recurso terapéutico no medicamentoso, por promover efecto de antirremodelado en pacientes con insuficiencia cardíaca. Este relato de caso describe las alteraciones ecocardiográficas de un paciente con Síndrome de Marfan durante cuatro años de un programa de fisioterapia cardiovascular.