Predictors of bleeding and thrombotic events among patients admitted to the hospital with COVID-19 and elevated D-dimer: insights from the ACTION randomized clinical trial.

Therapeutic anticoagulation showed inconsistent results in hospitalized patients with COVID-19 and selection of the best patients to use this strategy still a challenge balancing the risk of thrombotic and hemorrhagic outcomes. The present post-hoc analysis of the ACTION trial evaluated the variables independently associated with both bleeding events (major bleeding or clinically relevant non-major bleeding) and the composite outcomes thrombotic events (venous thromboembolism, myocardial infarction, stroke, systemic embolism, or major adverse limb events). Variables were assessed one by one with independent logistic regressions and final models were chosen based on Akaike information criteria. The model for bleeding events showed an area under the curve of 0.63 (95% confidence interval [CI] 0.53 to 0.73), while the model for thrombotic events had an area under the curve of 0.72 (95% CI 0.65 to 0.79). Non-invasive respiratory support was associated with thrombotic but not bleeding events, while invasive ventilation was associated with both outcomes (Odds Ratio of 7.03 [95 CI% 1.95 to 25.18] for thrombotic and 3.14 [95% CI 1.11 to 8.84] for bleeding events). Beyond respiratory support, creatinine level (Odds Ratio [OR] 1.01 95% CI 1.00 to 1.02 for every 1.0 mg/dL) and history of coronary disease (OR 3.67; 95% CI 1.32 to 10.29) were also independently associated to the risk of thrombotic events. Non-invasive respiratory support, history of coronary disease, and creatinine level may help to identify hospitalized COVID-19 patients at higher risk of thrombotic complications.ClinicalTrials.gov: NCT04394377.

The First Brazilian Cardiovascular Registry of Atrial Fibrillation: Primary Results of the RECALL Study.

BACKGROUND: It is estimated that atrial fibrillation (AF) affects approximately 1.5 million people in Brazil; however, epidemiological data are limited. We sought to evaluate the characteristics, treatment patterns, and clinical outcomes in patients with AF in Brazil by creating the first nationwide prospective registry. METHODS: RECALL was a multicenter, prospective registry that included and followed for 1 year 4,585 patients with AF at 89 sites across Brazil from April 2012 to August 2019. Patient characteristics, concomitant medication use, and clinical outcomes were analyzed using descriptive statistics and multivariable models. RESULTS: Of 4,585 patients enrolled, the median age was 70 (61, 78) years, 46% were women, and 53.8% had permanent AF. Only 4.4% of patients had a history of previous AF ablation and 25.2% had a previous cardioversion. The mean (SD) CHA2DS2-VASc score was 3.2 (1.6); median HAS-BLED score was 2 (2, 3). At baseline, 22% were not on anticoagulants. Of those taking anticoagulants, 62.6% were taking vitamin K antagonists and 37.4% were taking direct oral anticoagulants. The primary reasons for not using an oral anticoagulant were physician judgment (24.6%) and difficulty in controlling (14.7%) or performing (9.9%) INR. Mean (SD) TTR for the study period was 49.5% (27.5). During follow-up, the use of anticoagulants and INR in the therapeutic range increased to 87.1% and 59.1%, respectively. The rates/100 patient-years of death, hospitalization due to AF, AF ablation, cardioversion, stroke, systemic embolism, and major bleeding were 5.76 (5.12-6.47), 15.8 (14.6-17.0), 5.0 (4.4-5.7), 1.8 (1.4-2.2), 2.77 (2.32-3.32), 1.01 (0.75-1.36), and 2.21 (1.81-2.70). Older age, permanent AF, New York Heart Association class III/IV, chronic kidney disease, peripheral arterial disease, stroke, chronic obstructive pulmonary disease, and dementia were independently associated with increased mortality while the use of anticoagulant was associated with lower risk of death. CONCLUSIONS: RECALL represents the largest prospective registry of patients with AF in Latin America. Our findings highlight important gaps in treatment, which can inform clinical practice and guide future interventions to improve the care of these patients.

Therapeutic versus prophylactic anticoagulation for patients admitted to hospital with COVID-19 and elevated D-dimer concentration (ACTION): an open-label, multicentre, randomised, controlled trial.

BACKGROUND: COVID-19 is associated with a prothrombotic state leading to adverse clinical outcomes. Whether therapeutic anticoagulation improves outcomes in patients hospitalised with COVID-19 is unknown. We aimed to compare the efficacy and safety of therapeutic versus prophylactic anticoagulation in this population. METHODS: We did a pragmatic, open-label (with blinded adjudication), multicentre, randomised, controlled trial, at 31 sites in Brazil. Patients (aged ≥18 years) hospitalised with COVID-19 and elevated D-dimer concentration, and who had COVID-19 symptoms for up to 14 days before randomisation, were randomly assigned (1:1) to receive either therapeutic or prophylactic anticoagulation. Therapeutic anticoagulation was in-hospital oral rivaroxaban (20 mg or 15 mg daily) for stable patients, or initial subcutaneous enoxaparin (1 mg/kg twice per day) or intravenous unfractionated heparin (to achieve a 0·3-0·7 IU/mL anti-Xa concentration) for clinically unstable patients, followed by rivaroxaban to day 30. Prophylactic anticoagulation was standard in-hospital enoxaparin or unfractionated heparin. The primary efficacy outcome was a hierarchical analysis of time to death, duration of hospitalisation, or duration of supplemental oxygen to day 30, analysed with the win ratio method (a ratio >1 reflects a better outcome in the therapeutic anticoagulation group) in the intention-to-treat population. The primary safety outcome was major or clinically relevant non-major bleeding through 30 days. This study is registered with ClinicalTrials.gov (NCT04394377) and is completed. FINDINGS: From June 24, 2020, to Feb 26, 2021, 3331 patients were screened and 615 were randomly allocated (311 [50%] to the therapeutic anticoagulation group and 304 [50%] to the prophylactic anticoagulation group). 576 (94%) were clinically stable and 39 (6%) clinically unstable. One patient, in the therapeutic group, was lost to follow-up because of withdrawal of consent and was not included in the primary analysis. The primary efficacy outcome was not different between patients assigned therapeutic or prophylactic anticoagulation, with 28 899 (34·8%) wins in the therapeutic group and 34 288 (41·3%) in the prophylactic group (win ratio 0·86 [95% CI 0·59-1·22], p=0·40). Consistent results were seen in clinically stable and clinically unstable patients. The primary safety outcome of major or clinically relevant non-major bleeding occurred in 26 (8%) patients assigned therapeutic anticoagulation and seven (2%) assigned prophylactic anticoagulation (relative risk 3·64 [95% CI 1·61-8·27], p=0·0010). Allergic reaction to the study medication occurred in two (1%) patients in the therapeutic anticoagulation group and three (1%) in the prophylactic anticoagulation group. INTERPRETATION: In patients hospitalised with COVID-19 and elevated D-dimer concentration, in-hospital therapeutic anticoagulation with rivaroxaban or enoxaparin followed by rivaroxaban to day 30 did not improve clinical outcomes and increased bleeding compared with prophylactic anticoagulation. Therefore, use of therapeutic-dose rivaroxaban, and other direct oral anticoagulants, should be avoided in these patients in the absence of an evidence-based indication for oral anticoagulation. FUNDING: Coalition COVID-19 Brazil, Bayer SA.

Independent and Added Value of Cardiopulmonary Exercise Testing to New York Heart Association Classification in Patients With Heart Failure.

PURPOSE: The objective of this study was to evaluate the independent and added value of a cardiopulmonary exercise test (CPX) to New York Heart Association (NYHA) functional analysis in patients with heart failure (HF) and ejection fraction (EF) <50%. METHODS: Patients (n = 613) with HF and EF < 50% underwent CPX and were followed for 28 ± 17 mo with respect to primary outcomes (death or heart transplantation). RESULTS: Mean patient age was 57 ± 12 yr and 64% were male. Most patients were classified as NYHA class II (41%). The composite rate of primary outcomes was 12%; death occurred in 9% and heart transplant in 4%. Independent predictors of primary outcomes were: EF (HR = 0.95: 95% CI, 0.92-0.98; P = .001) and NYHA (HR = 2.06: 95% CI, 1.54-2.75; P < .0001). When added to the model, peak oxygen uptake (V˙ O2peak ) was an independent predictor (HR = 0.90: 95% CI, 0.84-0.96; P = .001), as was the percentage of predicted V˙ O2peak (HR = 0.03: 95% CI, 0.007-0.147; P < .001), minute ventilation/carbon dioxide production slope (HR = 1.02: 95% CI, 1.01-1.04; P = .012), and CPX score (HR = 1.16: 95% CI, 1.06-1.27; P = .001). CONCLUSIONS: CPX variables were independent predictors of HJ prognosis, even when controlled by NYHA functional class. Despite being independent predictors, the value added to NYHA classification was modest and lacked statistical significance.Patients with heart failure (HF) underwent cardiopulmonary exercise testing (CPX) and were followed with respect to primary outcomes (death or heart transplantation). Independent predictors of primary outcomes were: ejection fraction and New York Heart Association (NYHA). The CPX variables were independent predictors of HF prognosis, even when controlled by NYHA. However, the value added to NYHA classification was modest.

Scintigraphic and Echocardiographic Study of Patients with Pathogenic or Probably Pathogenic Variants of the TTR Gene without Overt Cardiac Involvement. / Avaliação Cintilográfica e Ecocardiográfica em Portadores de Variantes Patogênicas ou Provavelmente Patogênicas do Gene TTR sem Envolvimento Cardíaco Manifesto.

BACKGROUND: Transthyretin amyloidosis (ATTR) is an infiltrative disease caused by abnormal protein deposition mainly in the heart and peripheral nervous system. When it affects the heart, the disease presents as restrictive cardiomyopathy; when it affects the peripheral and autonomic nervous system, it manifests as polyneuropathy, and is called familial amyloid polyneuropathy (FAP). There are two ATTR subtypes: wild-type ATTR, where there is no mutation, and mutant ATTR (ATTRm), which is characterized by a mutation in the gene encoding the transthyretin protein (TTR). In both subtypes, cardiac involvement is the major marker of poor prognosis. OBJECTIVES: To assess the prevalence of subclinical cardiac involvement in a sample of patients with TTR gene mutation by using pyrophosphate scintigraphy and strain echocardiography; to compare scintigraphy and strain findings; to evaluate the association between neurological manifestations (FAP) and subclinical cardiac involvement; and to analyze whether there is an association between any specific mutation and cardiac involvement. METHODS: This is a cross-sectional study with carriers of the TTR gene mutation, without cardiovascular symptoms or changes in electrocardiographic or conventional echocardiographic parameters. All patients underwent pyrophosphate scintigraphy and strain echocardiography. Subclinical cardiac involvement was defined as a Perugini score ≥ 2, heart-to-contralateral lung (H/CL) ratio ≥ 1.5 at 1 h, H/CL ≥1.3 at 3 h, or global longitudinal strain (GLS) ≤ -17%. Descriptive and analytical analyses were performed and Fisher's exact test and Mann-Whitney test were applied. A value of p < 0.05 was considered significant. RESULTS: The 23 patients evaluated had a median age of 51 years (IQR 37-57 years), 15 (65.2%) were female, 12 (52.2%) were Pardo, nine (39.1%) had systemic arterial hypertension, and nine (39.1%) had a previous diagnosis of FAP. Of the nine patients with FAP, 8 (34.8%) were on tafamidis. The associated mutations were Val142IIe, Val50Met, and IIe127Val. The median GLS in the sample was -19% (-16% to -20%). Of the 23 patients, nine (39.1%; 95% CI = 29-49%) met criteria for cardiac involvement, six (26%) by the GLS-based criteria only. There was no association between having FAP and being an asymptomatic carrier, as assessed by strain echocardiography and pyrophosphate scintigraphy (p = 0.19). The prevalence of systemic arterial hypertension, diabetes mellitus, dyslipidemia, smoking, and reduced GLS did not differ between groups. Septal e' wave velocity was the only variable that significantly differed between individuals with and without reduced GLS, with an area under the ROC curve of 0.80 (95% CI = 0.61-0.98, p = 0.027). The best diagnostic accuracy was achieved with a septal e' velocity ≤ 8.5 cm/s. There was no association between mutation type and preclinical cardiac involvement, nor between tafamidis use and lower degree of cardiac involvement (37.5% versus 40.0%, p = 0.90). CONCLUSION: Subclinical cardiac involvement was common in a sample of TTR mutation carriers without cardiac involvement. Reduced left ventricular GLS was the most frequent finding. There was no association between the presence of amyloid polyneuropathy and subclinical cardiac involvement. Type of mutation was not associated with early cardiac involvement. In this sample, the use of tafamidis 20 mg/day was not associated with a lower prevalence of subclinical cardiac involvement.

FUNDAMENTO: A amiloidose por transtirretina (ATTR) é uma doença infiltrativa causada pela deposição anormal de proteína principalmente no coração e no sistema nervoso periférico. Quando acomete o coração, a doença manifesta-se como uma cardiomiopatia restritiva e, quando afeta o sistema nervoso periférico e autônomo, apresenta-se como uma polineuropatia, podendo ser chamada de Polineuropatia Amiloidótica Familiar (PAF). Existem dois subtipos de ATTR, a ATTR selvagem, em que não há variantes genéticas, e a ATTR hereditária, caracterizada por uma variante no gene que codifica a proteína transtirretina (T\TR). Em ambos os subtipos, o envolvimento cardíaco é o principal marcador prognóstico. OBJETIVOS: Avaliar a prevalência do envolvimento cardíaco subclínico em uma amostra de pacientes com variantes genéticas no gene TTR usando a cintilografia com pirofosfato e o ecocardiograma com strain; comparar os achados cintilográficos e as medidas de strain; avaliar a associação entre PAF e o envolvimento subclínico; e analisar se existe uma associação entre uma variante genética específica e o envolvimento cardíaco. MÉTODOS: Estudo transversal com carreadores de variantes no gene TTR sem sintomas cardiovasculares e sem alterações nos parâmetros da eletrocardiografia ou do ecocardiograma convencional. Todos os pacientes foram submetidos à cintilografia com pirofosfato e à ecocardiografia com análise de strain. O envolvimento cardíaco subclínico, definido como um escore de Perugini ≥ 2, razão Coração (C)/ Hemitórax Contralateral (CL) ≥ 1,5 em uma hora, C/CL ≥ 1,3 na terceira hora, ou um strain longitudinal global (SGL) ≤ −17%. Realizadas análises descritiva e analítica, e aplicados o teste exato de Fisher e o teste de Mann-Whitney. Um valor de p<0,05 foi considerado significativo. RESULTADOS: Os 23 pacientes avaliados apresentavam uma idade mediana de 51 (37-57) anos, 15 (65,2%) eram do sexo feminino, 12 (52,2%) eram pardos, nove (39,1%) apresentavam hipertensão arterial sistêmica, e nove (39,1%) tinham um diagnóstico prévio de PAF. Dos nove pacientes com PAF, oito (34,8%) usavam tafamidis. As variantes genéticas identificadas foram Val142IIe, Val50Met e IIe127Val. O valor mediano do SGL foi −19% (-16% ­ −20%). Dos 23 pacientes, nove (39,1%; 95% CI = 29­49%) preencheram os critérios de envolvimento cardíaco, seis (26%) somente pelo critério do SGL. Não houve associação entre PAF e um carreador assintomático avaliado por ecocardiograma com análise de strain e pela cintilografia com pirofostato (p=0,19). A prevalência de hipertensão arterial sistêmica, diabetes mellitus, dislipidemia, tabagismo e SGL reduzido não foi diferente entre os grupos. A velocidade da onda e' septal foi a única variável que apresentou diferença significativa entre os indivíduos com e sem SGL reduzido, com uma área sob a curva ROC de 0,80 (IC95% = 0,61­0,98, p = 0,027). A melhor acurácia diagnóstica foi alcançada com uma velocidade e' septal ≤ 8,5 cm/s. Não houve associação entre o tipo de variante genética e o envolvimento cardíaco pré-clínico, nem entre o uso de tafamidis e este mesmo envolvimento (37,5% versus 40,0%, p = 0,90). CONCLUSÃO: O envolvimento cardíaco subclínico foi frequente em uma amostra de carreadores da variante genética do gene TTR. Um valor do SGL reduzido foi o achado mais comum. Não houve associação entre a presença de polineuropatia amiloidótica e o envolvimento subclínico. O tipo de variante genética não foi associado com envolvimento cardíaco precoce. Nesta amostra, o uso de tafamidis (20mg/dia) não foi associado com uma menor prevalência de envolvimento cardíaco subclínico.

Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test. / Predição do Consumo de Oxigênio de Pico em Pacientes Cardiopatas com Base no Desempenho no Teste Timed Up and Go.

BACKGROUND: Central Illustration : Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test CPET: cardiopulmonary exercise test; TUG: timed up and go test; VO2peak: peak oxygen consumption. BACKGROUND: The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature. OBJECTIVES: Test the association between TUG and peak oxygen consumption (VO2peak), construct an equation based on TUG to predict VO2peak, and determine a cutoff point to estimate VO2peak ≥ 20 mL/kg/min. METHODS: This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05. RESULTS: The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO2peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO2peak and TUG was r = -0.54 (p < 0.001), and R2 was 0.30. The following equation was developed based on TUG: V O 2 peak = 33.553 + ( - 0.149 × age ) + ( - 0.738 × TUG ) + ( - 2.870 × sex ) ; a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R2: 0.40). The VO2peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO2peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86). CONCLUSIONS: TUG and VO2peak showed a significant association. A prediction equation for VO2peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.

Spirituality, Functional Gain, and Quality of Life in Cardiovascular Rehabilitation. / Espiritualidade, Ganho Funcional e Qualidade de Vida em Reabilitação Cardiovascular.

BACKGROUND: Religiosity and spirituality have been associated with higher recovery rates, greater adherence to treatments, and better levels of quality of life in patients with heart disease. OBJECTIVES: To evaluate the association between spirituality, functional gain, and improved quality of life in patients in a cardiovascular rehabilitation program. METHODS: This prospective cohort study evaluated the association between functional and quality of life gains during a cardiovascular rehabilitation program and a religiosity/spirituality index based on a validated scale. Depression, anxiety, and stress symptoms were screened for control purposes. P values < 0.05 were considered significant for all analyses. RESULTS: The study followed 57 patients (66 ± 12 years old; 71.7% male; 76% with coronary artery disease). The Spearman correlation coefficient did not show any associations between increases in functional capacity and organizational (rs = 0.110; p = 0.421), non-organizational (rs = -0.007; p = 0.421), or intrinsic (rs = -0.083; p = 0.543) religiosity. Furthermore, no associations were detected between the results of a quality of life score and organizational (rs = 0.22; p = 0.871), non-organizational (rs = 0.191; p = 0.159), or intrinsic (rs = 0.108; p = 0.429) religiosity. CONCLUSION: No association was detected between functional and quality of life gains and organizational, non-organizational, or intrinsic religiosity in this sample of patients undergoing cardiovascular rehabilitation.

FUNDAMENTO: Religiosidade e espiritualidade têm sido associadas a maiores taxas de recuperação, maior adesão a tratamentos e melhores níveis de qualidade de vida em pacientes cardiopatas. OBJETIVOS: Avaliar a associação entre espiritualidade, ganho funcional e melhoria de qualidade de vida em pacientes de um programa de reabilitação cardiovascular. MÉTODOS: Estudo de coorte prospectiva, no qual foi avaliada a associação entre os ganhos funcional e em qualidade de vida obtidos durante um programa de reabilitação cardiovascular e o índice de religiosidade/espiritualidade a partir de escala validada. Sintomas de depressão, ansiedade e estresse foram rastreados, para fins de controle. Um p < 0,05 foi adotado como padrão significante para todas as análises. RESULTADOS: Foram acompanhados 57 pacientes (66 ± 12 anos; 71,7% masculinos, 76% com doença arterial coronariana). O cálculo do coeficiente de correlação de Spearman não evidenciou associações entre incrementos na capacidade funcional e religiosidade organizacional (rs = 0,110; p = 0,421), não organizacional (rs = −0,007; p = 0,421) ou intrínseca (rs = −0,083; p = 0,543). Também não foram detectadas associações entre os resultados de um escore de qualidade de vida e religiosidade organizacional (rs = 0,22; p = 0,871), não organizacional (rs = 0,191; p = 0,159) ou intrínseca (rs = 0,108; p = 0,429). CONCLUSÃO: Não foi detectada associação entre ganho funcional ou em qualidade de vida e religiosidade organizacional, não organizacional ou intrínseca, nesta amostra de pacientes em reabilitação cardiovascular.

Low Concordance between NYHA Classification and Cardiopulmonary Exercise Test Variables in Patients with Heart Failure and Reduced Ejection Fraction. / Baixa Concordância entre a Classificação da NYHA e as Variáveis do Teste de Exercício Cardiopulmonar em Pacientes com Insuficiência Cardíaca e Fração de Ejeção Reduzida.

BACKGROUND: The New York Heart Association (NYHA) functional classification is the most commonly used classification system for heart failure (HF), whereas cardiopulmonary exercise testing (CPET) is the gold standard for functional status evaluation in HF. OBJECTIVE: This study aimed to analyze correlation and concordance between NYHA classes and CPET variables. METHODS: HF patients with clinical indication for CPET and ejection fraction (EF) < 50% were selected. Correlation (Spearman coefficient) and concordance (kappa) between NYHA classification and CPET-based classifications were analyzed. A p < 0.05 was accepted as significant. RESULTS: In total, 244 patients were included. Mean age was 56 ± 14 years, and mean EF was 35.5% ± 10%. Distribution of patients according to NYHA classification was 31.2%% class I, 48.3% class II, 19.2% class III, and 1.3% class IV. Correlation (r) between NYHA and Weber classes was 0.489 (p < 0.001), and concordance was 0.231 (p < 0.001). Correlation (r) between NYHA and ventilatory classes (minute ventilation/carbon dioxide production [VE/VCO2] slope) was 0.218 (p < 0.001), and concordance was 0.002 (p = 0.959). Spearman correlation between NYHA and CPET score classes was 0.223 (p = 0.004), and kappa concordance was 0.027 (p = 0.606). CONCLUSION: There was a moderate association between NYHA and Weber classes, although concordance was low. Ventilatory (VE/VCO2slope) and CPET score classes had a weak association and a low concordance with NYHA classes.

FUNDAMENTO: A classificação funcional da New York Heart Association (NYHA) é o sistema de classificação mais utilizado para a insuficiência cardíaca (IC), enquanto o teste de exercício cardiopulmonar (TECP) é o padrão ouro para a avaliação do estado funcional na IC. OBJETIVO: Analisar a correlação e a concordância entre as classes da NYHA e as variáveis do TECP. MÉTODOS: Foram selecionados pacientes com IC com indicação clínica para TECP e fração de ejeção (FE) < 50%. A correlação (coeficiente de Spearman) e a concordância (kappa) entre a classificação da NYHA e as classificações baseadas no TECP foram analisadas. Um valor de p < 0,05 foi considerado significativo. RESULTADOS: No total, foram incluídos 244 pacientes no estudo. A idade média foi de 56±14 anos, e a FE média foi de 35,5%±10%. A distribuição de pacientes de acordo com a classificação da NYHA foi a seguinte: classe I (31,2%), classe II (48,3%), classe III (19,2%) e classe IV (1,3%). A correlação (r) entre as classes da NYHA e de Weber foi de 0,489 (p < 0,001), e a concordância foi de 0,231 (p < 0,001). A correlação (r) entre as classes da NYHA e ventilatórias (inclinação da ventilação minuto/produção de dióxido de carbono [VE/VCO2]) foi de 0,218 (p < 0,001), e a concordância foi de 0,002 (p = 0,959). A correlação de Spearman entre as classes da NYHA e do escore TECP foi de 0,223 (p = 0,004), e a concordância kappa foi de 0,027 (p = 0,606). CONCLUSÃO: Foi identificada uma associação moderada entre as classes da NYHA e de Webber, embora a concordância tenha sido baixa. As classes ventilatórias (inclinação VE/VCO2) e do escore TECP apresentaram uma associação fraca e uma baixa concordância com as classes da NYHA.

The Six-Minute Step Test as a Predictor of Functional Capacity according to Peak VO2 in Cardiac Patients. / O Teste do Degrau de Seis Minutos como Preditor de Capacidade Funcional de Acordo com o Consumo de Oxigênio de Pico em Pacientes Cardíacos.

BACKGROUND: Six-minute step test (6MST) is a simple way to evaluate functional capacity, although it has not been well studied in patients with coronary artery disease (CAD) or heart failure (HF). OBJECTIVE: Analyze the association between the 6MST and peak oxygen uptake (VO2peak) and develop an equation for estimating VO2peak based on the 6MST, as well as to determine a cutoff point for the 6MST that predicts a VO2peak ≥20 mL.Kg-1.min-1. METHODS: In 171 patients who underwent the 6MST and a cardiopulmonary exercise test, correlation, regression, and ROC analysis were used and a p < 0.05 was admitted as significant. RESULTS: mean age was 60±14 years and 74% were male. Mean left ventricle ejection fraction was 57±16%, 74% had CAD and 28% had HF. Mean VO2peak was 19±6 mL.Kg-1.min-1 and mean 6MST performance was 87±45 steps. Association between 6MST and VO2peak was r 0.69 (p <0.001). The model VO2peak =19.6 + (0.075 x 6MST) - (0.10 x age) for men and VO2peak =19.6 + (0.075 x 6MST) - (0.10 x age) - 2 for women could predict VO2peak based on 6MST results (adjusted R 0.72; adjusted R2 0.53). The most accurate cutoff point for 6MST to predict a VO2peak ≥20 mL.Kg-1.min-1 was >105 steps (AUC 0.85; 95% CI 0.79 -0.90; p <0.001). CONCLUSION: An equation for predicting VO2peak based on 6MST results was derived, and a significant association was found between 6MST and VO2peak. The cutoff point for 6MST, which predicts a VO2peak ≥20 mL.Kg-1.min-1, was >105 steps. (Arq Bras Cardiol. 2021; 116(5):889-895).

FUNDAMENTO: O teste do degrau de seis minutos (TD6) é uma forma simples de avaliar a capacidade funcional, embora tenha sido pouco estudado em pacientes com doença arterial coronariana (DAC) ou insuficiência cardíaca (IC). OBJETIVO: Analisar a associação entre o TD6 e o consumo de oxigênio de pico (VO2pico) e desenvolver uma equação que estime o VO2pico com base no TD6, bem como determinar um ponto de corte para o TD6 que preveja um VO2pico ≥ 20 mL.kg-1.min-1. MÉTODOS: Nos 171 pacientes submetidos ao TD6 e a um teste de exercício cardiopulmonar, análises da curva ROC, de regressão e de correlação foram usadas, e um p < 0,05 foi admitido como significativo. RESULTADOS: A idade média foi 60±14 anos, e 74% eram do sexo masculino. A média da fração de ejeção ventricular esquerda foi 57±16%; 74% apresentavam DAC, e 28%, IC. A média do VO2pico foi 19±6 mL.kg-1.min-1, e o desempenho médio do TD6 foi 87±45 passos. A associação entre o TD6 e o VO2pico foi r 0,69 (p < 0,001). Os modelos VO2pico = 19,6 + (0,075 x TD6) ­ (0,10 x idade) para homens e VO2pico = 19,6 + (0,075 x TD6) ­ (0,10 x idade) ­ 2 para mulheres poderiam prever o VO2pico com base nos resultados do TD6 (R ajustado 0,72; R2 ajustado 0,53). O ponto de corte mais acurado para que o TD6 preveja um VO2pico ≥ 20 mL.kg-1.min-1 foi de > 105 passos [área sob a curva 0,85; intervalo de confiança de 95% 0,79 - 0,90; p < 0,001]. CONCLUSÃO: Uma equação que preveja o VO2pico com base nos resultados do TD6 foi derivada, e foi encontrada uma associação significativa entre o TD6 e o VO2pico. O ponto de corte do TD6, que prevê um VO2pico ≥ 20 mL.kg-1.min-1, foi > 105 passos. (Arq Bras Cardiol. 2021; 116(5):889-895).

Factors Associated with Recurrence in Takotsubo Syndrome: A Systematic Review.

BACKGROUND: Takotsubo syndrome (TTS) is characterized by a temporary systolic dysfunction of the left ventricle (LV) related to a stressful event. However, the factors associated with its recurrence are still not well established. OBJECTIVE: To analyze the main factors associated with TTS recurrence. METHODS: A systematic review was performed using the PRISMA model. Observational studies, published between January 2008 and October 2017, which presented a recurrence rate of at least 3% and/or 5 or more patients with recurrence, and who met at least 80% of the STROBE criteria were included. RESULTS: six articles reached the criteria to compose this systematic review. The recurrence rate ranged from 1 to 3.5% per year (global recurrence rate 3.8%). One study associated higher recurrence rate with the female gender, four reported the time between the first and second episodes, one study associated body mass index (BMI) and hypercontractility of the LV middle anterior wall to a higher recurrence rate. No association between recurrence and electrocardiographic changes were determined. Beta-blockers use was not associated with recurrence rates. CONCLUSIONS: Female gender, time from the first episode of the syndrome, low BMI and midventricular obstruction were reported as potential predictors of TTS recurrence.

Importance of Genetic Testing in Dilated Cardiomyopathy: Applications and Challenges in Clinical Practice.

Dilated cardiomyopathy (DCM) is a clinical syndrome characterized by left ventricular dilatation and contractile dysfunction. It is the most common cause of heart failure in young adults. The advent of next-generation sequencing has contributed to the discovery of a large amount of genomic data related to DCM. Mutations involving genes that encode cytoskeletal proteins, the sarcomere, and ion channels account for approximately 40% of cases previously classified as idiopathic DCM. In this scenario, geneticists and cardiovascular genetics specialists have begun to work together, building knowledge and establishing more accurate diagnoses. However, proper interpretation of genetic results is essential and multidisciplinary teams dedicated to the management and analysis of the obtained information should be considered. In this review, we approach genetic factors associated with DCM and their prognostic relevance and discuss how the use of genetic testing, when well recommended, can help cardiologists in the decision-making process.

Avaliação Cintilográfica e Ecocardiográfica em Portadores de Variantes Patogênicas ou Provavelmente Patogênicas do Gene TTR sem Envolvimento Cardíaco Manifesto / Scintigraphic and Echocardiographic Study of Patients with Pathogenic or Probably Pathogenic Variants of the TTR Gene without Overt Cardiac Involvement

Resumo Fundamento: A amiloidose por transtirretina (ATTR) é uma doença infiltrativa causada pela deposição anormal de proteína principalmente no coração e no sistema nervoso periférico. Quando acomete o coração, a doença manifesta-se como uma cardiomiopatia restritiva e, quando afeta o sistema nervoso periférico e autônomo, apresenta-se como uma polineuropatia, podendo ser chamada de Polineuropatia Amiloidótica Familiar (PAF). Existem dois subtipos de ATTR, a ATTR selvagem, em que não há variantes genéticas, e a ATTR hereditária, caracterizada por uma variante no gene que codifica a proteína transtirretina (T/TR). Em ambos os subtipos, o envolvimento cardíaco é o principal marcador prognóstico. Objetivos: Avaliar a prevalência do envolvimento cardíaco subclínico em uma amostra de pacientes com variantes genéticas no gene TTR usando a cintilografia com pirofosfato e o ecocardiograma com strain; comparar os achados cintilográficos e as medidas de strain; avaliar a associação entre PAF e o envolvimento subclínico; e analisar se existe uma associação entre uma variante genética específica e o envolvimento cardíaco. Métodos: Estudo transversal com carreadores de variantes no gene TTR sem sintomas cardiovasculares e sem alterações nos parâmetros da eletrocardiografia ou do ecocardiograma convencional. Todos os pacientes foram submetidos à cintilografia com pirofosfato e à ecocardiografia com análise de strain. O envolvimento cardíaco subclínico, definido como um escore de Perugini ≥ 2, razão Coração (C)/ Hemitórax Contralateral (CL) ≥ 1,5 em uma hora, C/CL ≥ 1,3 na terceira hora, ou um strain longitudinal global (SGL) ≤ −17%. Realizadas análises descritiva e analítica, e aplicados o teste exato de Fisher e o teste de Mann-Whitney. Um valor de p<0,05 foi considerado significativo. Resultados: Os 23 pacientes avaliados apresentavam uma idade mediana de 51 (37-57) anos, 15 (65,2%) eram do sexo feminino, 12 (52,2%) eram pardos, nove (39,1%) apresentavam hipertensão arterial sistêmica, e nove (39,1%) tinham um diagnóstico prévio de PAF. Dos nove pacientes com PAF, oito (34,8%) usavam tafamidis. As variantes genéticas identificadas foram Val142IIe, Val50Met e IIe127Val. O valor mediano do SGL foi −19% (-16% - −20%). Dos 23 pacientes, nove (39,1%; 95% CI = 29-49%) preencheram os critérios de envolvimento cardíaco, seis (26%) somente pelo critério do SGL. Não houve associação entre PAF e um carreador assintomático avaliado por ecocardiograma com análise de strain e pela cintilografia com pirofostato (p=0,19). A prevalência de hipertensão arterial sistêmica, diabetes mellitus, dislipidemia, tabagismo e SGL reduzido não foi diferente entre os grupos. A velocidade da onda e' septal foi a única variável que apresentou diferença significativa entre os indivíduos com e sem SGL reduzido, com uma área sob a curva ROC de 0,80 (IC95% = 0,61-0,98, p = 0,027). A melhor acurácia diagnóstica foi alcançada com uma velocidade e' septal ≤ 8,5 cm/s. Não houve associação entre o tipo de variante genética e o envolvimento cardíaco pré-clínico, nem entre o uso de tafamidis e este mesmo envolvimento (37,5% versus 40,0%, p = 0,90). Conclusão: O envolvimento cardíaco subclínico foi frequente em uma amostra de carreadores da variante genética do gene TTR. Um valor do SGL reduzido foi o achado mais comum. Não houve associação entre a presença de polineuropatia amiloidótica e o envolvimento subclínico. O tipo de variante genética não foi associado com envolvimento cardíaco precoce. Nesta amostra, o uso de tafamidis (20mg/dia) não foi associado com uma menor prevalência de envolvimento cardíaco subclínico.

Abstract Background: Transthyretin amyloidosis (ATTR) is an infiltrative disease caused by abnormal protein deposition mainly in the heart and peripheral nervous system. When it affects the heart, the disease presents as restrictive cardiomyopathy; when it affects the peripheral and autonomic nervous system, it manifests as polyneuropathy, and is called familial amyloid polyneuropathy (FAP). There are two ATTR subtypes: wild-type ATTR, where there is no mutation, and mutant ATTR (ATTRm), which is characterized by a mutation in the gene encoding the transthyretin protein (TTR). In both subtypes, cardiac involvement is the major marker of poor prognosis. Objectives: To assess the prevalence of subclinical cardiac involvement in a sample of patients with TTR gene mutation by using pyrophosphate scintigraphy and strain echocardiography; to compare scintigraphy and strain findings; to evaluate the association between neurological manifestations (FAP) and subclinical cardiac involvement; and to analyze whether there is an association between any specific mutation and cardiac involvement. Methods: This is a cross-sectional study with carriers of the TTR gene mutation, without cardiovascular symptoms or changes in electrocardiographic or conventional echocardiographic parameters. All patients underwent pyrophosphate scintigraphy and strain echocardiography. Subclinical cardiac involvement was defined as a Perugini score ≥ 2, heart-to-contralateral lung (H/CL) ratio ≥ 1.5 at 1 h, H/CL ≥1.3 at 3 h, or global longitudinal strain (GLS) ≤ −17%. Descriptive and analytical analyses were performed and Fisher's exact test and Mann-Whitney test were applied. A value of p < 0.05 was considered significant. Results: The 23 patients evaluated had a median age of 51 years (IQR 37-57 years), 15 (65.2%) were female, 12 (52.2%) were Pardo, nine (39.1%) had systemic arterial hypertension, and nine (39.1%) had a previous diagnosis of FAP. Of the nine patients with FAP, 8 (34.8%) were on tafamidis. The associated mutations were Val142IIe, Val50Met, and IIe127Val. The median GLS in the sample was −19% (−16% to −20%). Of the 23 patients, nine (39.1%; 95% CI = 29-49%) met criteria for cardiac involvement, six (26%) by the GLS-based criteria only. There was no association between having FAP and being an asymptomatic carrier, as assessed by strain echocardiography and pyrophosphate scintigraphy (p = 0.19). The prevalence of systemic arterial hypertension, diabetes mellitus, dyslipidemia, smoking, and reduced GLS did not differ between groups. Septal e' wave velocity was the only variable that significantly differed between individuals with and without reduced GLS, with an area under the ROC curve of 0.80 (95% CI = 0.61-0.98, p = 0.027). The best diagnostic accuracy was achieved with a septal e' velocity ≤ 8.5 cm/s. There was no association between mutation type and preclinical cardiac involvement, nor between tafamidis use and lower degree of cardiac involvement (37.5% versus 40.0%, p = 0.90). Conclusion: Subclinical cardiac involvement was common in a sample of TTR mutation carriers without cardiac involvement. Reduced left ventricular GLS was the most frequent finding. There was no association between the presence of amyloid polyneuropathy and subclinical cardiac involvement. Type of mutation was not associated with early cardiac involvement. In this sample, the use of tafamidis 20 mg/day was not associated with a lower prevalence of subclinical cardiac involvement.

Predição do Consumo de Oxigênio de Pico em Pacientes Cardiopatas com Base no Desempenho no Teste Timed Up and Go / Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test

Resumo Fundamento A utilização do teste timed up and go (TUG) na avaliação da aptidão cardiorrespiratória em cardiopatas não está bem definida na literatura. Objetivos Testar a associação entre o TUG e o consumo de oxigênio de pico (VO2pico), construir uma equação com base no TUG para prever o VO2pico e determinar um ponto de corte para estimar um VO2pico ≥ 20 mL.kg−1.min−1. Métodos Estudo transversal com 201 indivíduos portadores de doença arterial coronariana ou insuficiência cardíaca, com idade entre 36 e 92 anos, submetidos ao TUG e ao teste cardiopulmonar de exercício. Foram realizadas análises de correlação, curva ROC, regressão linear múltipla e Bland-Altman. Um p < 0,05 foi adotado como significante. Resultados A média de idade da amostra total foi 67 ± 13 anos, e 70% dos participantes eram do sexo masculino. A média de VO2pico foi de 17 ± 6 mL.kg−1.min−1 e a média de desempenho no TUG foi de 7 ± 2,5 segundos. A correlação entre o VO2pico e o TUG foi r = −0,54 (p < 0,001) e R2 de 0,30. Foi desenvolvida a equação com base no TUG: V O 2 pico = 33 , 553 + ( − 0 , 149 ∗ idade ) + ( − 0 , 738 ∗ T U G ) + ( − 2 , 870 ∗ sexo ); sendo atribuído o valor 0 ao sexo masculino e 1 ao sexo feminino (R ajustado: 0,41; R2 ajustado: 0,40). O VO2pico estimado pela equação foi 18,81 ± 3,2 mL.kg−1.min−1 e o determinado pelo teste cardiopulmonar de exercício foi 18,18 ± 5,9 mL.kg−1.min−1 (p > 0,05). O melhor ponto de corte para o VO2pico ≥ 20 mL.kg−1.min−1 foi de ≤ 5,47 segundos (área sob a curva: 0,80; intervalo de confiança de 95%: 0,74 a 0,86). Conclusões O TUG e o VO2pico apresentaram associação significativa. A equação preditiva do VO2pico foi desenvolvida e validada internamente com bom desempenho. O ponto de corte no TUG para prever um VO2pico ≥ 20 mL.kg−1.min−1 foi ≤ 5,47 segundos.

Abstract Background The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature. Objectives Test the association between TUG and peak oxygen consumption (VO2peak), construct an equation based on TUG to predict VO2peak, and determine a cutoff point to estimate VO2peak ≥ 20 mL/kg/min. Methods This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05. Results The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO2peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO2peak and TUG was r = −0.54 (p < 0.001), and R2 was 0.30. The following equation was developed based on TUG: V O 2 peak = 33.553 + ( − 0.149 × age ) + ( − 0.738 × TUG ) + ( − 2.870 × sex ); a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R2: 0.40). The VO2peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO2peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86). Conclusions TUG and VO2peak showed a significant association. A prediction equation for VO2peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.

Espiritualidade, Ganho Funcional e Qualidade de Vida em Reabilitação Cardiovascular / Spirituality, Functional Gain, and Quality of Life in Cardiovascular Rehabilitation

Resumo Fundamento Religiosidade e espiritualidade têm sido associadas a maiores taxas de recuperação, maior adesão a tratamentos e melhores níveis de qualidade de vida em pacientes cardiopatas. Objetivos Avaliar a associação entre espiritualidade, ganho funcional e melhoria de qualidade de vida em pacientes de um programa de reabilitação cardiovascular. Métodos Estudo de coorte prospectiva, no qual foi avaliada a associação entre os ganhos funcional e em qualidade de vida obtidos durante um programa de reabilitação cardiovascular e o índice de religiosidade/espiritualidade a partir de escala validada. Sintomas de depressão, ansiedade e estresse foram rastreados, para fins de controle. Um p < 0,05 foi adotado como padrão significante para todas as análises. Resultados Foram acompanhados 57 pacientes (66 ± 12 anos; 71,7% masculinos, 76% com doença arterial coronariana). O cálculo do coeficiente de correlação de Spearman não evidenciou associações entre incrementos na capacidade funcional e religiosidade organizacional (rs = 0,110; p = 0,421), não organizacional (rs = −0,007; p = 0,421) ou intrínseca (rs = −0,083; p = 0,543). Também não foram detectadas associações entre os resultados de um escore de qualidade de vida e religiosidade organizacional (rs = 0,22; p = 0,871), não organizacional (rs = 0,191; p = 0,159) ou intrínseca (rs = 0,108; p = 0,429). Conclusão Não foi detectada associação entre ganho funcional ou em qualidade de vida e religiosidade organizacional, não organizacional ou intrínseca, nesta amostra de pacientes em reabilitação cardiovascular.

Abstract Background Religiosity and spirituality have been associated with higher recovery rates, greater adherence to treatments, and better levels of quality of life in patients with heart disease. Objectives To evaluate the association between spirituality, functional gain, and improved quality of life in patients in a cardiovascular rehabilitation program. Methods This prospective cohort study evaluated the association between functional and quality of life gains during a cardiovascular rehabilitation program and a religiosity/spirituality index based on a validated scale. Depression, anxiety, and stress symptoms were screened for control purposes. P values < 0.05 were considered significant for all analyses. Results The study followed 57 patients (66 ± 12 years old; 71.7% male; 76% with coronary artery disease). The Spearman correlation coefficient did not show any associations between increases in functional capacity and organizational (rs = 0.110; p = 0.421), non-organizational (rs = −0.007; p = 0.421), or intrinsic (rs = −0.083; p = 0.543) religiosity. Furthermore, no associations were detected between the results of a quality of life score and organizational (rs = 0.22; p = 0.871), non-organizational (rs = 0.191; p = 0.159), or intrinsic (rs = 0.108; p = 0.429) religiosity. Conclusion No association was detected between functional and quality of life gains and organizational, non-organizational, or intrinsic religiosity in this sample of patients undergoing cardiovascular rehabilitation.

Dysautonomia Evaluation by Holter in Chagas Heart Disease

Abstract Background Sudden cardiac death is the main lethal mechanism associated with Chagas cardiomyopathy. Studies suggest that dysautonomia may represent a relevant, intense, independent, and early phenomenon in the natural history of the disease, even when ventricular systolic function is preserved, and may also be the mechanism that triggers malignant ventricular arrhythmias. Objective To evaluate the degree of dysautonomia and its possible association with ventricular arrhythmias in patients with Chagas cardiomyopathy, according to different categories of mortality risk, as defined by the score proposed by Rassi, used as a surrogate outcome for death. Methods A cross-sectional study involving 43 patients with Chagas cardiomyopathy stratified into risk categories based on the Rassi score, with 23 being classified as low risk and 20 as intermediate-to-high risk. Heart rate variability (HRV) was assessed using Holter monitoring for long-term recordings of 24 hours (time domain) and for short-term recordings of 5 minutes (frequency domain) at rest and after autonomic tests: deep breathing and Valsalva maneuver. The HRV variables were compared between the groups using the Student's t-test and α=0.05. Results Comparison of the results between the risk stratification groups showed no differences in HRV indexes, either in the time or frequency domain. However, results showed a significant increase in the number of arrhythmias as a function of increased risk (p=0.02). Conclusion There was no association between the degree of dysautonomia, evaluated by Holter monitoring, and the categories of mortality risk, despite a direct association between the rate of arrhythmias and the higher risk group.

Baixa Concordância entre a Classificação da NYHA e as Variáveis do Teste de Exercício Cardiopulmonar em Pacientes com Insuficiência Cardíaca e Fração de Ejeção Reduzida / Low Concordance between NYHA Classification and Cardiopulmonary Exercise Test Variables in Patients with Heart Failure and Reduced Ejection Fraction

Resumo Fundamento A classificação funcional da New York Heart Association (NYHA) é o sistema de classificação mais utilizado para a insuficiência cardíaca (IC), enquanto o teste de exercício cardiopulmonar (TECP) é o padrão ouro para a avaliação do estado funcional na IC. Objetivo Analisar a correlação e a concordância entre as classes da NYHA e as variáveis do TECP. Métodos Foram selecionados pacientes com IC com indicação clínica para TECP e fração de ejeção (FE) < 50%. A correlação (coeficiente de Spearman) e a concordância (kappa) entre a classificação da NYHA e as classificações baseadas no TECP foram analisadas. Um valor de p < 0,05 foi considerado significativo. Resultados No total, foram incluídos 244 pacientes no estudo. A idade média foi de 56±14 anos, e a FE média foi de 35,5%±10%. A distribuição de pacientes de acordo com a classificação da NYHA foi a seguinte: classe I (31,2%), classe II (48,3%), classe III (19,2%) e classe IV (1,3%). A correlação (r) entre as classes da NYHA e de Weber foi de 0,489 (p < 0,001), e a concordância foi de 0,231 (p < 0,001). A correlação (r) entre as classes da NYHA e ventilatórias (inclinação da ventilação minuto/produção de dióxido de carbono [VE/VCO2]) foi de 0,218 (p < 0,001), e a concordância foi de 0,002 (p = 0,959). A correlação de Spearman entre as classes da NYHA e do escore TECP foi de 0,223 (p = 0,004), e a concordância kappa foi de 0,027 (p = 0,606). Conclusão Foi identificada uma associação moderada entre as classes da NYHA e de Webber, embora a concordância tenha sido baixa. As classes ventilatórias (inclinação VE/VCO2) e do escore TECP apresentaram uma associação fraca e uma baixa concordância com as classes da NYHA.

Abstract Background The New York Heart Association (NYHA) functional classification is the most commonly used classification system for heart failure (HF), whereas cardiopulmonary exercise testing (CPET) is the gold standard for functional status evaluation in HF. Objective This study aimed to analyze correlation and concordance between NYHA classes and CPET variables. Methods HF patients with clinical indication for CPET and ejection fraction (EF) < 50% were selected. Correlation (Spearman coefficient) and concordance (kappa) between NYHA classification and CPET-based classifications were analyzed. A p < 0.05 was accepted as significant. Results In total, 244 patients were included. Mean age was 56 ± 14 years, and mean EF was 35.5% ± 10%. Distribution of patients according to NYHA classification was 31.2%% class I, 48.3% class II, 19.2% class III, and 1.3% class IV. Correlation (r) between NYHA and Weber classes was 0.489 (p < 0.001), and concordance was 0.231 (p < 0.001). Correlation (r) between NYHA and ventilatory classes (minute ventilation/carbon dioxide production [VE/VCO2] slope) was 0.218 (p < 0.001), and concordance was 0.002 (p = 0.959). Spearman correlation between NYHA and CPET score classes was 0.223 (p = 0.004), and kappa concordance was 0.027 (p = 0.606). Conclusion There was a moderate association between NYHA and Weber classes, although concordance was low. Ventilatory (VE/VCO2slope) and CPET score classes had a weak association and a low concordance with NYHA classes.

Cardiopulmonary Exercise Test: Background, Applicability and Interpretation.

Cardiopulmonary exercise test (CPET) has been gaining importance as a method of functional assessment in Brazil and worldwide. In its most frequent applications, CPET consists in applying a gradually increasing intensity exercise until exhaustion or until the appearance of limiting symptoms and/or signs. The following parameters are measured: ventilation; oxygen consumption (VO2); carbon dioxide production (VCO2); and the other variables of conventional exercise testing. In addition, in specific situations, pulse oximetry and flow-volume loops during and after exertion are measured. The CPET provides joint data analysis that allows complete assessment of the cardiovascular, respiratory, muscular and metabolic systems during exertion, being considered gold standard for cardiorespiratory functional assessment.1-6 The CPET allows defining mechanisms related to low functional capacity that can cause symptoms, such as dyspnea, and correlate them with changes in the cardiovascular, pulmonary and skeletal muscle systems. Furthermore, it can be used to provide the prognostic assessment of patients with heart or lung diseases, and in the preoperative period, in addition to aiding in a more careful exercise prescription to healthy subjects, athletes and patients with heart or lung diseases. Similarly to CPET clinical use, its research also increases, with the publication of several scientific contributions from Brazilian researchers in high-impact journals. Therefore, this study aimed at providing a comprehensive review on the applicability of CPET to different clinical situations, in addition to serving as a practical guide for the interpretation of that test. Resumo O teste cardiopulmonar de exercício (TCPE) vem ganhando importância crescente como método de avaliação funcional tanto no Brasil quanto no Mundo. Nas suas aplicações mais frequentes, o teste consiste em submeter o indivíduo a um exercício de intensidade gradativamente crescente até a exaustão ou o surgimento de sintomas e/ou sinais limitantes. Neste exame se mensura a ventilação (VE), o consumo de oxigênio (VO2), a produção de gás carbônico (VCO2) e as demais variáveis de um teste de exercício convencional. Adicionalmente, podem ser verificadas, em situações específicas, a oximetria de pulso e as alças fluxo-volume antes, durante e após o esforço. A análise integrada dos dados permite a completa avaliação dos sistemas cardiovascular, respiratório, muscular e metabólico no esforço, sendo considerado padrão-ouro na avaliação funcional cardiorrespiratória.1-6 O TCPE permite definir mecanismos relacionados à baixa capacidade funcional, os quais podem ser causadores de sintomas como a dispneia, correlacionando-os com alterações dos sistemas cardiovascular, pulmonar e musculoesquelético. Também pode ser de grande aplicabilidade na avaliação prognóstica em cardiopatas, pneumopatas e em pré-operatório, além de auxiliar na prescrição mais criteriosa do exercício em sujeitos normais, em atletas, em cardiopatas e em pneumopatas. Assim como ocorre com o uso clínico, a pesquisa nesse campo também cresce e várias contribuições científicas de pesquisadores nacionais são publicadas em periódicos de alto fator de impacto. Sendo assim, o objetivo deste documento é fornecer uma revisão ampla da aplicabilidade do TCPE nas diferentes situações clínicas, bem como servir como guia prático na interpretação desse teste propedêutico.

O Teste do Degrau de Seis Minutos como Preditor de Capacidade Funcional de Acordo com o Consumo de Oxigênio de Pico em Pacientes Cardíacos / The Six-Minute Step Test as a Predictor of Functional Capacity according to Peak VO2 in Cardiac Patients

Resumo Fundamento: O teste do degrau de seis minutos (TD6) é uma forma simples de avaliar a capacidade funcional, embora tenha sido pouco estudado em pacientes com doença arterial coronariana (DAC) ou insuficiência cardíaca (IC). Objetivo: Analisar a associação entre o TD6 e o consumo de oxigênio de pico (VO2pico) e desenvolver uma equação que estime o VO2pico com base no TD6, bem como determinar um ponto de corte para o TD6 que preveja um VO2pico ≥ 20 mL.kg-1.min-1 Métodos: Nos 171 pacientes submetidos ao TD6 e a um teste de exercício cardiopulmonar, análises da curva ROC, de regressão e de correlação foram usadas, e um p < 0,05 foi admitido como significativo. Resultados: A idade média foi 60±14 anos, e 74% eram do sexo masculino. A média da fração de ejeção ventricular esquerda foi 57±16%; 74% apresentavam DAC, e 28%, IC. A média do VO2pico foi 19±6 mL.kg-1.min-1, e o desempenho médio do TD6 foi 87±45 passos. A associação entre o TD6 e o VO2pico foi r 0,69 (p < 0,001). Os modelos VO2pico = 19,6 + (0,075 x TD6) - (0,10 x idade) para homens e VO2pico = 19,6 + (0,075 x TD6) - (0,10 x idade) - 2 para mulheres poderiam prever o VO2pico com base nos resultados do TD6 (R ajustado 0,72; R2 ajustado 0,53). O ponto de corte mais acurado para que o TD6 preveja um VO2pico ≥ 20 mL.kg-1.min-1 foi de > 105 passos [área sob a curva 0,85; intervalo de confiança de 95% 0,79 - 0,90; p < 0,001]. Conclusão: Uma equação que preveja o VO2pico com base nos resultados do TD6 foi derivada, e foi encontrada uma associação significativa entre o TD6 e o VO2pico. O ponto de corte do TD6, que prevê um VO2pico ≥ 20 mL.kg-1.min-1, foi > 105 passos. (Arq Bras Cardiol. 2021; 116(5):889-895)

Abstract Background: Six-minute step test (6MST) is a simple way to evaluate functional capacity, although it has not been well studied in patients with coronary artery disease (CAD) or heart failure (HF). Objective: Analyze the association between the 6MST and peak oxygen uptake (VO2peak) and develop an equation for estimating VO2peak based on the 6MST, as well as to determine a cutoff point for the 6MST that predicts a VO2peak ≥20 mL.Kg-1.min-1 Methods: In 171 patients who underwent the 6MST and a cardiopulmonary exercise test, correlation, regression, and ROC analysis were used and a p < 0.05 was admitted as significant. Results: mean age was 60±14 years and 74% were male. Mean left ventricle ejection fraction was 57±16%, 74% had CAD and 28% had HF. Mean VO2peak was 19±6 mL.Kg-1.min-1 and mean 6MST performance was 87±45 steps. Association between 6MST and VO2peak was r 0.69 (p <0.001). The model VO2peak =19.6 + (0.075 x 6MST) - (0.10 x age) for men and VO2peak =19.6 + (0.075 x 6MST) - (0.10 x age) - 2 for women could predict VO2peak based on 6MST results (adjusted R 0.72; adjusted R2 0.53). The most accurate cutoff point for 6MST to predict a VO2peak ≥20 mL.Kg-1.min-1 was >105 steps (AUC 0.85; 95% CI 0.79 -0.90; p <0.001). Conclusion: An equation for predicting VO2peak based on 6MST results was derived, and a significant association was found between 6MST and VO2peak. The cutoff point for 6MST, which predicts a VO2peak ≥20 mL.Kg-1.min-1, was >105 steps. (Arq Bras Cardiol. 2021; 116(5):889-895)