The Effect of Being Pregnant during Respiratory Pandemics: A Comparison between 2009/10 Flu and 2020/21 COVID-19 Pandemic in Brazil.

Pregnant women undergo physiological changes that make them a challenging group of patients during pandemic respiratory diseases, as previously found during H1N1 2009 pandemic and recently ratified in COVID-19 pandemic. We conducted a retrospective cohort analysis on 5888 hospitalized women for H1N1 flu pandemic (2190 pregnant and 3698 non-pregnant) and 64,515 hospitalized women for COVID-19 pandemic (5151 pregnant and 59,364 non-pregnant), from the Brazilian national database, to compare demographic profile, clinical aspects, and mortality in childbearing aged women during both pandemics. Additionally, the effect of being pregnant was compared between both pandemics. In both pandemics, pregnant women were younger than non-pregnant women. Overall, pregnant women had lower frequencies of comorbidities and were less symptomatic. Among hospitalized women, pregnant women presented lower mortality rates than non-pregnant women (9.7% vs. 12.6%, p = 0.002 in the H1N1 pandemic and 9.7% vs. 17.4%, p < 0.001 in the COVID-19 pandemic) and this difference was statistically more pronounced in the COVID-19 pandemic, even after balancing pregnant and non-pregnant groups regarding age and chronic diseases.

Impact of SARS-CoV-2 on pregnancy and neonatal outcomes: An open prospective study of pregnant women in Brazil.

OBJECTIVES: To determine the incidence and risk of adverse obstetric and neonatal outcomes according to SARS-CoV-2 infection severity in pregnant women. METHOD: Open prospective study of pregnant women tested for SARS-CoV-2 by serological and molecular assays during pregnancy or delivery in two hospitals in Sao Paulo, Brazil from April 12, 2020, to February 28, 2021. Five groups were considered for analysis: C0, negative COVID-19 results and no COVID-19 symptoms; C1, positive COVID-19 results, and no symptoms; C2, positive COVID-19 results with mild symptoms; C3, positive COVID-19 results with moderate symptoms; and C4, positive COVID-19 results with severe symptoms. The association between obstetric and neonatal outcomes and COVID-19 severity was determined using multivariate analysis. RESULTS: 734 eligible pregnant women were enrolled as follows: C0 (n = 357), C1 (n = 127), C2 (n = 174), C3 (n = 37), and C4 (n = 39). The following pregnancy and neonatal outcomes were associated with severe COVID-19: oligohydramnios (adjusted Odds Ratio [aOR] = 6.18; 95% CI 1.87‒20.39), fetal distress (aOR = 4.01; 95% Confidence Interval [CI] 1.84‒8.75), preterm birth (aOR = 5.51; 95% CI 1.47‒20.61), longer hospital stay (aOR = 1.66; 95% CI 1.36‒2.02), and admission to the neonatal intensive care unit (aOR = 19.36; 95% CI, 5.86‒63.99). All maternal (n = 6, 15.4%, p < 0.001) and neonatal (n = 5, 12.5%, p < 0.001) deaths and most fetal deaths (n = 4, 9.8%, p < 0.001) occurred in C4 group. Moderate COVID-19 was associated with oligohydramnios (aOR = 6.23; 95% CI 1.93‒20.13) and preterm birth (aOR = 3.60; 95% CI 1.45‒9.27). Mild COVID-19 was associated with oligohydramnios (aOR = 3.77; 95% CI 1.56‒9.07). CONCLUSION: Adverse pregnancy and neonatal outcomes were associated with maternal symptomatic COVID-19 status, and risk increased with disease severity.

The Influenza Vaccine May Protect Pregnant and Postpartum Women against Severe COVID-19.

The SARS-CoV-2 pandemic has imposed a huge challenge on the antenatal care of pregnant women worldwide, with the maternal mortality rate being raised to alarming levels. While COVID-19 vaccines were developed, some studies highlighted a possible relationship between influenza vaccination and lower odds of COVID-19 infection. As obstetric patients belong to a high-risk group for respiratory diseases, this study evaluated whether influenza vaccination reduces the severity of COVID-19 infection and mortality among pregnant and postpartum women. We conducted a retrospective cohort study on 3370 pregnant and postpartum women from the Brazilian national database, where they were grouped according to their influenza vaccination status before the onset of COVID-19 symptoms. The intensive care unit admission and intubation rates were significantly higher among subjects in the unvaccinated group (p = 0.002 and p < 0.001, respectively). The odds of mortality risk among those who received the vaccine was 0.33, with a 95% confidence interval of 0.23-0.47. The numbers of patients who needed to be vaccinated to avoid a case of intensive care unit admission, intubation, or death due to COVID-19 were 11, 15, and 11, respectively. Influenza vaccines could confer protection against severe COVID-19 infection in pregnant and postpartum women.

Impact of SARS-CoV-2 on pregnancy and neonatal outcomes: An open prospective study of pregnant women in Brazil

Abstract Objectives: To determine the incidence and risk of adverse obstetric and neonatal outcomes according to SARS-CoV-2 infection severity in pregnant women. Method: Open prospective study of pregnant women tested for SARS-CoV-2 by serological and molecular assays during pregnancy or delivery in two hospitals in Sao Paulo, Brazil from April 12, 2020, to February 28, 2021. Five groups were considered for analysis: C0, negative COVID-19 results and no COVID-19 symptoms; C1, positive COVID-19 results, and no symptoms; C2, positive COVID-19 results with mild symptoms; C3, positive COVID-19 results with moderate symptoms; and C4, positive COVID-19 results with severe symptoms. The association between obstetric and neonatal outcomes and COVID-19 severity was determined using multivariate analysis. Results: 734 eligible pregnant women were enrolled as follows: C0 (n = 357), C1 (n = 127), C2 (n = 174), C3 (n = 37), and C4 (n = 39). The following pregnancy and neonatal outcomes were associated with severe COVID-19: oligohydramnios (adjusted Odds Ratio [aOR] = 6.18; 95% CI 1.87‒20.39), fetal distress (aOR = 4.01; 95% Confidence Interval [CI] 1.84‒8.75), preterm birth (aOR = 5.51; 95% CI 1.47‒20.61), longer hospital stay (aOR = 1.66; 95% CI 1.36‒2.02), and admission to the neonatal intensive care unit (aOR = 19.36; 95% CI, 5.86‒63.99). All maternal (n = 6, 15.4%, p < 0.001) and neonatal (n = 5, 12.5%, p < 0.001) deaths and most fetal deaths (n = 4, 9.8%, p < 0.001) occurred in C4 group. Moderate COVID-19 was associated with oligohydramnios (aOR = 6.23; 95% CI 1.93‒20.13) and preterm birth (aOR = 3.60; 95% CI 1.45‒9.27). Mild COVID-19 was associated with oligohydramnios (aOR=3.77; 95% CI 1.56‒9.07). Conclusion: Adverse pregnancy and neonatal outcomes were associated with maternal symptomatic COVID-19 status, and risk increased with disease severity. HIGHLIGHTS COVID-19 increases the rates of adverse pregnancy and neonatal outcomes. Serious cases are associated with oligohydramnios, fetal distress, prematurity, neonatal ICU admission, maternal and neonatal deaths. The maternal clinical status dictates obstetric and neonatal outcomes.

Diet Quality Indices and Physical Activity Levels Associated with Adequacy of Gestational Weight Gain in Pregnant Women with Gestational Diabetes Mellitus.

The aim of this study was to evaluate the Diet Quality Index (DQI) and the Physical Activity (PA) levels associated with adequacy of gestational weight gain in pregnant women with gestational diabetes mellitus (GDM). A total of 172 pregnant women with a single fetus and a diagnosis of GDM participated. Food intake was self-reported on the food frequency questionnaire and DQI was quantified using the index validated and revised for Brazil (DQI-R). To assess PA, the Pregnancy Physical Activity Questionnaire was administered. Gestational weight gain was classified, following the criteria of the Institute of Medicine, into adequate (AWG), insufficient (IWG), or excessive (EWG) weight gain. A multinomial logistic regression analysis was performed, with level of significance <0.05. The participants were divided into 3 groups: AWG (33.1%), IWG (27.3%), and EWG (39.5%). The analysis indicated that if the pregnant women PA fell into tertile 1 or 2, then they had a greater chance of having IWG, whereas those with the lowest scores on the DQI-R, whose PA fell into tertile 2, and pregestational obesity women had the greatest chance of having EWG. This study has shown that low PA levels may contribute towards IWG. On the other hand, a low final DQI-R score, representing inadequate food habits, low PA levels, and pregestational obesity may increase the chance of EWG in patients with GDM.

[The influence of breastfeeding in postpartum oral glucose tolerance test in women with recent gestational diabetes mellitus]. / Influência da amamentação nos resultados do teste oral de tolerância à glicose pós-parto de mulheres com diabetes mellitusgestacional.

PURPOSE: To determine the influence of breastfeeding on the results of a postpartum oral glucose tolerance test in women recently diagnosed with gestational diabetes mellitus. METHODS: The data were obtained from the electronic medical records of the Endocrinopathy Sector during pregnancy, HCMED laboratory system ofHospital das Clínicas of São Paulo , and by telephone. According to the inclusion criteria adopted, 132 patients were eligible for the study. For statistical analysis, the patients were divided into two groups according to whether or not they breastfed. The results were analyzed by the Student t-test and by the Mann-Whitney, Chi-square and Fisher's exact tests, depending on the variable analyzed, with the level of significance set at p<0.05. RESULTS: Of the 132 patients included in the study, 114 breastfed and 18 did not. Most of the patients in both groups were overweight or obese. The breastfeeding group had a lower pre-pregnancy Body Mass Index than the non-breastfeeding group (p=0.006). Insulin was introduced earlier in the group that did not breastfeed (23.21±4.33 versus 28.84±6.17; p=0.04). The group that did not breastfeed had a higher mean postpartum fasting glucose value in the oral glucose tolerance test than the group that breastfed (91.3±8.7 versus 86.5±9.3; p=0.01). Breastfeeding acted as a protective factor against the development of glucose intolerance in the postpartum oral glucose tolerance test (OR=0.27; 95%CI 0.09-0.8). By logistic regression, breastfeeding was shown to be an independent protective factor. CONCLUSION: There was a statistically significant relationship between breastfeeding and a decreased risk of developing glucose intolerance. Breastfeeding should be encouraged because it is an effective, low cost intervention easily accessible to all patients during the postpartum period.

Influência da amamentação nos resultados do teste oral de tolerância à glicose pós-parto de mulheres com diabetes mellitusgestacional / The influence of breastfeeding in postpartum oral glucose tolerance test in women with recent gestational diabetes mellitus

Resumo OBJETIVO: Avaliar a influência da amamentação nos resultados do teste oral de tolerância à glicose pós-parto (TTGp) de mulheres que apresentaram diabetes gestacional atendidas em unidade terciária do município de São Paulo. MÉTODOS: Foram obtidos dados de pacientes com diabetes gestacional no período de janeiro a dezembro de 2014. As informações foram obtidas por meio de acesso aos prontuários eletrônicos e pelo contato telefônico. Seguindo os critérios de inclusão adotados, 132 pacientes foram elegíveis para o estudo. Para análise estatística dos dados, as pacientes foram divididas em dois grupos, segundo a informação de terem ou não amamentado. Foram utilizados os testest de Student, de Mann-Whitney, do χ2 e exato de Fisher, dependendo do tipo de variável analisada. Foram considerados estatisticamente significativos testes com p<0,05. RESULTADOS: Das 132 pacientes incluídas no estudo, 114 amamentaram e 18 não amamentaram. Em ambos os grupos, houve um predomínio de pacientes na faixa do sobrepeso e/ou obesidade. As pacientes que amamentaram apresentaram índice de massa corporal (IMC) pré-gestacional menor que as que não amamentaram (p=0,006). No grupo que não amamentou, a idade gestacional de introdução de insulina foi mais precoce (23.21±4.33 versus 28.84±6.17; (p=0,04) e o valor médio da glicemia de jejum do TTGp (91.3±8.7 versus 86.5±9.3; (p=0,01) foi maior do que o grupo que amamentou. A amamentação agiu como fator protetor para o desenvolvimento de intolerância à glicose no TTGp (OR=0,27; IC95% 0,09-0,8). Pela regressão logística, a amamentação mostrou-se ser fator protetor independente. CONCLUSÃO: Houve relação estatisticamente significativa entre a amamentação e a diminuição do risco de desenvolver intolerância à glicose. Esse ato deve ser estimulado, visto que é uma intervenção efetiva de baixo custo e fácil acesso a todas as pacientes no puerpério.

Abstract PURPOSE: To determine the influence of breastfeeding on the results of a postpartum oral glucose tolerance test in women recently diagnosed with gestational diabetes mellitus. METHODS: The data were obtained from the electronic medical records of the Endocrinopathy Sector during pregnancy, HCMED laboratory system ofHospital das Clínicas of São Paulo , and by telephone. According to the inclusion criteria adopted, 132 patients were eligible for the study. For statistical analysis, the patients were divided into two groups according to whether or not they breastfed. The results were analyzed by the Student t-test and by the Mann-Whitney, Chi-square and Fisher's exact tests, depending on the variable analyzed, with the level of significance set at p<0.05. RESULTS: Of the 132 patients included in the study, 114 breastfed and 18 did not. Most of the patients in both groups were overweight or obese. The breastfeeding group had a lower pre-pregnancy Body Mass Index than the non-breastfeeding group (p=0.006). Insulin was introduced earlier in the group that did not breastfeed (23.21±4.33 versus 28.84±6.17; p=0.04). The group that did not breastfeed had a higher mean postpartum fasting glucose value in the oral glucose tolerance test than the group that breastfed (91.3±8.7 versus 86.5±9.3; p=0.01). Breastfeeding acted as a protective factor against the development of glucose intolerance in the postpartum oral glucose tolerance test (OR=0.27; 95%CI 0.09-0.8). By logistic regression, breastfeeding was shown to be an independent protective factor. CONCLUSION: There was a statistically significant relationship between breastfeeding and a decreased risk of developing glucose intolerance. Breastfeeding should be encouraged because it is an effective, low cost intervention easily accessible to all patients during the postpartum period.

[Can genital infections alter the results of preterm birth predictive tests?]. / As infecções genitais podem alterar os resultados dos testes preditivos do parto prematuro?

PURPOSE: To determine if the presence of infectious agents in vaginal or cervical content can alter the results of the insulin-like growth factor binding protein-1 (phIGFBP-1) test and the measurement of cervical length (CC) by transvaginal ultrasonography. METHODS: A total of 107 pregnant women with a history of spontaneous preterm birth were submitted to the phIGFBP-1 test and to measurement of CC by transvaginal ultrasonography every 3 weeks, between 24 and 34 weeks of gestation. Genital infections were determined immediately before testing. The patients were distributed into four groups (GA, GB, GC, and GD) and the correlation between genital infection and changes in the tests was determined within each group based on the odds ratio (OR) and the Pearson correlation coefficient. RESULTS: In each group, over 50% of the patients had genital infections (GA 10/17; GB 28/42; GC 15/24; GD 35/53), with bacterial vaginosis being the main alteration of the vaginal flora. Positive results for phIGFBP-1(GA 10/10; GB 18/28; GC 15/15; GD 19/35) and CC ≤ 20 mm (GA 10/10; GB 20/28; GC 10/15; GD 20/35) were obtained more frequently in patients with genital infection in all groups. Nonetheless, when applying the Pearson correlation coefficient we detected a poor correlation between genital infection and positivity for markers. CONCLUSION: The presence of changes in the vaginal flora and of other genital infections does not significantly alter the results of phIGFBP-1 and the measurement of cervical length when compared to cases without infection. However, more studies with larger samples are necessary to confirm these results.

As infecções genitais podem alterar os resultados dos testes preditivos do parto prematuro? / Can genital infections alter the results of preterm birth predictive tests?

OBJETIVOS: Verificar se a presença de agentes infecciosos no conteúdo vaginal ou cervical pode alterar os resultados dos testes da proteína-1 fosforilada ligada ao fator de crescimento insulina-símile (phIGFBP-1) e das medidas do comprimento do colo uterino (CC) pela ultrassonografia transvaginal. MÉTODOS: Um total de 107 gestantes com antecedente de prematuridade espontânea foram submetidas ao teste da phIGFBP-1 e à realização da ultrassonografia transvaginal para medida do comprimento do colo uterino, a cada três semanas, entre 24 e 34 semanas. As infecções genitais foram pesquisadas imediatamente antes da realização dos testes. As pacientes foram distribuídas em quatro grupos (GA, GB, GC e GD) e dentro de cada grupo foi avaliada a correlação entre infecção genital e alteração nos testes utilizando a análise das razões de chance (OR) e o coeficiente de correlação de Pearson. RESULTADOS: Em cada grupo, mais de 50% das pacientes apresentaram infecção genital (GA 10/17; GB 28/42; GC 15/24; GD 35/53), sendo a vaginose bacteriana a principal alteração de flora vaginal. O resultado positivo para phIGFBP-1 (GA 10/10; GB 18/28; GC 15/15; GD 19/35) e CC≤20 mm (GA 10/10; GB 20/28; GC 10/15; GD 20/35) foram os resultados encontrados com maior frequência nas pacientes com infecção genital em todos os grupos. Porém, aplicando o coeficiente de correlação de Pearson foi identificada correlação entre infecção genital e positividade para os marcadores. CONCLUSÃO: A presença de alteração da flora vaginal e de outras infecções genitais não alteram significativamente os resultados do teste da phIGFBP-1 e da medida do colo uterino quando comparados aos casos sem infecção. No entanto, é necessária ...

PURPOSE: To determine if the presence of infectious agents in vaginal or cervical content can alter the results of the insulin-like growth factor binding protein-1 (phIGFBP-1) test and the measurement of cervical length (CC) by transvaginal ultrasonography. METHODS: A total of 107 pregnant women with a history of spontaneous preterm birth were submitted to the phIGFBP-1 test and to measurement of CC by transvaginal ultrasonography every 3 weeks, between 24 and 34 weeks of gestation. Genital infections were determined immediately before testing. The patients were distributed into four groups (GA, GB, GC, and GD) and the correlation between genital infection and changes in the tests was determined within each group based on the odds ratio (OR) and the Pearson correlation coefficient. RESULTS: In each group, over 50% of the patients had genital infections (GA 10/17; GB 28/42; GC 15/24; GD 35/53), with bacterial vaginosis being the main alteration of the vaginal flora. Positive results for phIGFBP-1(GA 10/10; GB 18/28; GC 15/15; GD 19/35) and CC≤20 mm (GA 10/10; GB 20/28; GC 10/15; GD 20/35) were obtained more frequently in patients with genital infection in all groups. Nonetheless, when applying the Pearson correlation coefficient we detected a poor correlation between genital infection and positivity for markers. CONCLUSION: The presence of changes in the vaginal flora and of other genital infections does not significantly alter the results of phIGFBP-1 and the measurement of cervical length when compared to cases without infection. However, more studies with larger samples are necessary to confirm these results. .

Infecção genital e marcadores preditivos do parto prematuro / Genital infection and preterm birth predictive markers

Apesar dos avanços na área da Obstetrícia, a prematuridade ainda é a principal causa de morbidade e mortalidade neonatal. Esforços continuam sendo feitos na busca de marcadores que possam predizer tal evento e, assim, evitar o parto prematuro. A presente revisão abordou a relação da infecção genital com a prematuridade e sua influência nos resultados dos principais indicadores preditivos do parto prematuro, bem como a eficácia da antibioticoterapia. Os estudos revisados sugerem que o tratamento da vaginose bacteriana relaciona-se a resultados satisfatórios para a prevenção da prematuridade somente se realizado na primeira metade da gestação. A alteração dos testes preditivos não indica, por si só, o uso de antibióticos.

Despite advances in the field of Obstetrics, prematurity is still responsible for the leading cause of neonatal morbidity and mortality. Efforts are still being made in the search for markers that can predict such an event and thus prevent premature delivery. This review explores the relationship of genital infection with preterm birth and its influence on the results of the main preterm birth predictive markers, as well as the effectiveness of antibiotics. The revised studies suggest that treatment of bacterial vaginosis relates to satisfactory results for the prevention of preterm performed only if the first half of pregnancy. The change of predictive tests not indicates, by itself, the use of antibiotics.

Anatomical variations in the human sinuatrial nodal artery.

OBJECTIVE: To analyze the anatomical variations of sinuatrial nodal branch(es) of the coronary artery mainly regarding their number; a recent report from Japan claims the presence of 2 branches in up to 50% of cases, an occurrence that would permit adequate flow compensation in case of occlusion or section of 1 of these branches. METHODS: The sinuatrial nodal branch(es) of 50 human hearts fixed in formol solution were dissected with the aid of a Normo Health 3.0 degree visor magnifying lens, measured, and classified as to the origin, route, and number of branches. RESULTS: In 94% (n = 47) of cases, a single sinuatrial nodal branch was found. classified: (A) two right side types, R1 (in 46% of cases, n = 23), situated medial to the right auricle and R2 (in 4% of cases, n = 2), situated on the posterior surface of the right atrium; (B) three left side types, L1 (in 24% of cases, n = 12), situated medial to the left auricle, L2 (in 16% of cases, n = 8), situated posterior to the left auricle, and L3 (in 4% of cases, n = 2), situated on the posterior surface of the left atrium. Except for R2, each type was subdivided into 'a' or 'b' types, according to whether the sinuatrial nodal branch(es) occurred in a clockwise or counterclockwise orientation around the base of the superior cava vena. In 4% of cases (n = 2), 2 sinuatrial nodal branch(es) were observed with 1 branch originating from each of the coronary arteries. In 1 case (2%), 3 sinuatrial nodal branch(es) were found, 2 from the right coronary artery and the third probably from the bronchial branch of the thoracic aorta. In 30% of the cases, the sinuatrial nodal branch(es) formed a ring around the base of the superior cava vena. In all cases, the sinuatrial nodal branch(es) supplied collateral branches to the atrium and/or the auricle of the same side as its origin and/or to the opposite side. CONCLUSION: The low frequency of 2 sinuatrial nodal branch(es) in Brazilian individuals, compared to the higher frequency found among the Japanese, is probably due to a variation associated with ethnic group origin.

Anatomical variations in the human sinuatrial nodal artery / As variações de número, origem e trajeto do ramo do nó sinoatrial em corações humanos

OBJECTIVE: To analyze the anatomical variations of sinuatrial nodal branch(es) of the coronary artery mainly regarding their number; a recent report from Japan claims the presence of 2 branches in up to 50 percent of cases, an occurrence that would permit adequate flow compensation in case of occlusion or section of 1 of these branches. METHODS: The sinuatrial nodal branch(es) of 50 human hearts fixed in formol solution were dissected with the aid of a Normo Health 3.0 degree visor magnifying lens, measured, and classified as to the origin, route, and number of branches. RESULTS: In 94 percent (n = 47) of cases, a single sinuatrial nodal branch was found. classified: (A) two right side types, R1 (in 46 percent of cases, n = 23), situated medial to the right auricle and R2 (in 4 percent of cases, n = 2), situated on the posterior surface of the right atrium; (B) three left side types, L1 (in 24 percent of cases, n = 12), situated medial to the left auricle, L2 (in 16 percent of cases, n = 8), situated posterior to the left auricle, and L3 (in 4 percent of cases, n = 2), situated on the posterior surface of the left atrium. Except for R2, each type was subdivided into 'a' or 'b' types, according to whether the sinuatrial nodal branch(es) occurred in a clockwise or counterclockwise orientation around the base of the superior cava vena. In 4 percent of cases (n = 2), 2 sinuatrial nodal branch(es) were observed with 1 branch originating from each of the coronary arteries. In 1 case (2 percent), 3 sinuatrial nodal branch(es) were found, 2 from the right coronary artery and the third probably from the bronchial branch of the thoracic aorta. In 30 percent of the cases, the sinuatrial nodal branch(es) formed a ring around the base of the superior cava vena. In all cases, the sinuatrial nodal branch(es) supplied collateral branches to the atrium and/or the auricle of the same side as its origin and/or to the opposite side. CONCLUSION: The low frequency of 2 sinuatrial...

OBJETIVO: Analisar as variações anatômicas do ramo do nó sinoatrial, principalmente quanto ao número, visto que a escola japonesa relatou a presença de dois ramos em até 50 por cento dos casos, fato que permitiria a compensação, em caso de oclusão ou secção de um dos ramos. MÉTODOS: O ramo do nó sinoatrial foi dissecado com o auxílio de lente de aumento com pala Normo Health, de 3,0 graus, em 50 corações fixados em solução de formol. RESULTADOS: Em 94 por cento dos casos, havia um ramo do nó sinoatrial, classificado em dois tipos do lado direito: D1 (46 por cento) - ramo do nó sinoatrial situado medialmente à aurícula direita; D2 (4 por cento) - ramo do nó sinoatrial na face posterior do átrio direito; e três tipos do lado esquerdo: E1 (24 por cento) - ramo do nó sinoatrial medial à aurícula esquerda; E2 (16 por cento) - posterior à aurícula esquerda; E3 (4 por cento) - na face posterior do átrio esquerdo. Cada tipo, exceto D2, era subdividido em a ou b, conforme o sentido do RNSA fosse, respectivamente horário ou anti-horário ao redor da base da veia cava superior. Em 4 por cento dos casos, havia dois ramos do nó sinoatrial, originados de ambas as artérias coronárias. Em 2 por cento dos casos, havia três ramos do nó sinoatrial originados, dois da artéria coronária direita e o terceiro, provavelmente de artéria brônquica. Em 30 por cento dos casos, o ramo do nó sinoatrial formava um anel ao redor da base da veia cava superior. Em todos os casos, o ramo do nó sinoatrial forneceu ramos colaterais para o átrio e/ou a aurícula do mesmo lado e/ou do lado oposto à sua origem. CONCLUSÃO: A baixa freqüência de dois ramos do nó sinoatrial em indivíduos brasileiros, comparada à alta encontrada em japoneses, provavelmente seja variação associada com as diferentes origens étnicas.