Prognostic Prediction of Cardiopulmonary Exercise Test Parameters in Heart Failure Patients with Atrial Fibrillation / Previsão Prognóstica dos Parâmetros do Teste de Esforço Cardiopulmonar em Pacientes com Insuficiência Cardíaca e Fibrilação Atrial

Abstract Background: Atrial fibrillation (AF) is associated with increased mortality in heart failure (HF) patients. Objective: To evaluate whether the risk of AF patients can be precisely stratified by relation with cardiopulmonary exercise test (CPET) cut-offs for heart transplantation (HT) selection. Methods: Prospective evaluation of 274 consecutive HF patients with left ventricular ejection fraction ≤ 40%. The primary endpoint was a composite of cardiac death or urgent HT in 1-year follow-up. The primary endpoint was analysed by several CPET parameters for the highest area under the curve and for positive (PPV) and negative predictive value (NPV) in AF and sinus rhythm (SR) patients to detect if the current cut-offs for HT selection can precisely stratify the AF group. Statistical differences with a p-value <0.05 were considered significant. Results: There were 51 patients in the AF group and 223 in the SR group. The primary outcome was higher in the AF group (17.6% vs 8.1%, p = 0.038). The cut-off value of pVO2 for HT selection showed a PPV of 100% and an NPV of 95.5% for the primary outcome in the AF group, with a PPV of 38.5% and an NPV of 94.3% in the SR group. The cut-off value of VE/VCO2 slope showed lower values of PPV (33.3%) and similar NPV (92.3%) to pVO2 results in the AF group. Conclusion: Despite the fact that AF carries a worse prognosis for HF patients, the current cut-off of pVO2 for HT selection can precisely stratify this high-risk group.

Resumo Fundamento: A fibrilação atrial (FA) está associada ao aumento da mortalidade em pacientes com insuficiência cardíaca (IC). Objetivo: Avaliar se o risco de pacientes com FA pode ser estratificado com precisão em relação aos pontos de corte do teste de esforço cardiopulmonar (TECP) para seleção do transplante cardíaco (TC). Métodos: Avaliação prospectiva de 274 pacientes consecutivos com IC com fração de ejeção do ventrículo esquerdo ≤ 40%. O endpoint primário foi um composto de morte cardíaca ou TC urgente no seguimento de 1 ano. O endpoint primário foi analisado através de vários parâmetros do TECP para a maior área sob a curva e para o valor preditivo positivo (VPP) e negativo (VPN) em pacientes com FA e ritmo sinusal (RS) para detectar se os atuais pontos de corte para a seleção de TC podem estratificar com precisão o grupo com FA. Diferenças estatísticas com valor de p < 0,05 foram consideradas significativas. Resultados: Havia 51 pacientes no grupo de FA e 223 no grupo RS. O endpoint primário foi maior no grupo FA (17,6% vs. 8,1%, p = 0,038). O valor de corte de pVO2 para a seleção do TC mostrou um VPP de 100% e um VPN de 95,5% para o endpoint primário no grupo FA, com um VPP de 38,5% e um VPN de 94,3% no grupo RS. O valor de corte da inclinação VE/VCO2 apresentou valores mais baixos de VPP (33,3%) e valor semelhante de VPN (92,3%) aos resultados de pVO2 no grupo FA. Conclusões: Apesar do fato de a FA apresentar um pior prognóstico para os pacientes com IC, o atual ponto de corte de pVO2 para a seleção de TC pode estratificar com precisão esse grupo de alto risco.

Hypothyroidism is a risk factor for atrial fibrillation after coronary artery bypass graft

Abstract Introduction: Few reports in the world have shown a differential effect of hypothyroidism in relation to morbidity and mortality following cardiac surgery. Objective: To determine the association between preoperative hypothyroidism, composite and disaggregated outcomes of mortality and complications in patients undergoing first-time isolated myocardial revascularization surgery. Methods: Historical cohort of patients undergoing myocardial revascularization between January 2008 and December 2014, with 626 patients included for evaluation of the composite and disaggregated outcomes of in-hospital mortality and complications (atrial fibrillation, surgical site infection and reoperation due to bleeding). A logistic regression model was used to determine the association between hypothyroidism and the onset of those outcomes. Results: Cohort of 1696 eligible patients for the study, with 1.8 mortality. Median age, female gender and prevalence of arterial hypertension were all significantly higher among hypothyroid patients. No differences were found in other preoperative or intraoperative characteristics. Hypothyroidism was associated with the presence of the composite outcome, RR 1.6 (1.04-2.4) and atrial fibrillation 1.9 (1.05-3.8). No association with mortality, infections or reoperation due to bleeding was found. Conclusion: Hypothyroidism is a disease that affects females predominantly and does not determine the presence of other comorbidities. Hypothyroidism is a risk factor for the onset of postoperative fibrillation in patients undergoing myocardial revascularization surgery. Postoperative care protocols focused on the prevention of these complications in this type of patients must be instituted.

Efectividad y seguridad del tratamiento anticoagulante con acenocumarol en fibrilación auricular no valvular / Effectiveness and safety of oral anticoagulation treatment with acenocoumarol in non-valvular atrial fibrillation

Background: Vitamin K antagonists significantly decrease the incidence of stroke but increase the risk of bleeding. Aim: To assess the effectiveness and risk of bleeding of vitamin K antagonists in non-valvular atrial fibrillation. Material and Methods: Retrospective cohort study of 524 patients, 236 women (45%) and 288 men (55%) with non-valvular atrial fibrillation (NVAF) admitted to the oral anticoagulation treatment (OAT) clinic at four public hospitals, between 2009 and 2012. They were followed until March 2013, measuring the quality of OAT, ischemic and bleeding events. Results: The mean follow-up was 26.1 months, with 1,154.7 person-years of follow-up accrued. The percentage of time in therapeutic range (TTR) was 35.2 ± 18%; this was deemed to represent the quality of OAT. The cumulative incidence of ischemic events, either stroke or systemic embolism, was 2.25/100 person-years, being greater in patients with previous embolism (Risk ratio 5.21, 95% confidence intervals 2.31- 11.73, p < 0.01). The cumulative incidence of major bleeding events-extracranial and intracraneal-was 4.08/100 person-years. The main site of extracranial major bleeding was the gastrointestinal tract (32%). Conclusions: In our clinical practice, the effectiveness of OAT with acenocoumarol in NVAF patients is similar to that published abroad. However, the incidence of bleeding complications is higher. The quality of the OAT measured by the TTR was lower than abroad.

Surgical treatment of atrial fibrillation in patients with rheumatic valve disease

Abstract Objective: To assess heart rhythm and predictive factors associated with sinus rhythm after one year in patients with rheumatic valve disease undergoing concomitant surgical treatment of atrial fibrillation. Operative mortality, survival and occurrence of stroke after one year were also evaluated. Methods: Retrospective longitudinal observational study of 103 patients undergoing rheumatic mitral valve surgery and ablation of atrial fibrillation using uni- or bipolar radiofrequency between January 2013 and December 2014. Age, gender, functional class (NYHA), type of atrial fibrillation, EuroSCORE, duration of atrial fibrillation, stroke, left atrial size, left ventricular ejection fraction, cardiopulmonary bypass time, myocardial ischemia time and type of radiofrequency were investigated. Results: After one year, 66.3% of patients were in sinus rhythm. Sinus rhythm at hospital discharge, lower left atrial size in the preoperative period and bipolar radiofrequency were associated with a greater chance of sinus rhythm after one year. Operative mortality was 7.7%. Survival rate after one year was 92.3% and occurrence of stroke was 1%. Conclusion: Atrial fibrillation ablation surgery with surgical approach of rheumatic mitral valve resulted in 63.1% patients in sinus rhythm after one year. Discharge from hospital in sinus rhythm was a predictor of maintenance of this rhythm. Increased left atrium and use of unipolar radiofrequency were associated with lower chance of sinus rhythm. Operative mortality rate of 7.7% and survival and stroke-free survival contribute to excellent care results for this approach.

Idade avançada e incidência de fibrilação atrial em pós-operatório de troca valvar aórtica / Advanced age and incidence of atrial fibrillation in the postoperative period of aortic valve replacement

Objetivo: Descrever, em idosos, a correlação entre faixa etária e ocorrência de fibrilação atrial após cirurgia por estenose aórtica, além de avaliar a influência da ocorrência de fibrilação atrial na incidência de acidente vascular cerebral, tempo de internação e mortalidade hospitalar. Métodos: Estudo transversal retrospectivo incluindo pacientes com idade > 70 anos submetidos à cirurgia de troca valvar aórtica isolada. Resultados: Foram estudados 348 pacientes com idade média de 76,8±4,6 anos. A incidência de fibrilação atrial no pós-operatório foi 32,8% (n=114), sendo superior nos pacientes > 80 anos (42,9 vs. 28,8% 70-79 anos, P=0,017) e havendo significância estatística limítrofe (P=0,055) para tendência linear na correlação idade e incidência de fibrilação atrial. Verificou-se significativo maior tempo de internação na Unidade de Terapia Intensiva e hospitalar total, porém, não se observou maior taxa de acidente vascular cerebral ou de mortalidade hospitalar decorrente da fibrilação atrial. Conclusão: A incidência de fibrilação atrial no pós-operatório de cirurgia para estenose valvar aórtica em pacientes idosos com > 70 anos foi elevada e linearmente correlacionada ao avanço da idade, especialmente após 80 anos, causando aumento dos tempos de internação total e em Unidade de Terapia Intensiva, sem aumento significativo da morbimortalidade. O conhecimento desses dados é importante para evidenciar a necessidade de medidas profiláticas e de tratamento precoce dessa arritmia nesse subgrupo. .

Objective: This study aims to describe the correlation between age and occurrence of atrial fibrillation after aortic stenosis surgery in the elderly as well as evaluate the influence of atrial fibrillation on the incidence of strokes, hospital length of stay, and hospital mortality. Methods: Cross-sectional retrospective study of > 70 year-old patients who underwent isolated aortic valve replacement. Results: 348 patients were included in the study (mean age 76.8±4.6 years). Overall, post-operative atrial fibrillation was 32.8% (n=114), but it was higher in patients aged 80 years and older (42.9% versus 28.8% in patients aged 70-79 years, P=0.017). There was borderline significance for linear correlation between age and atrial fibrillation (P=0.055). Intensive Care Unit and hospital lengths of stay were significantly increased in atrial fibrillation (P<0.001), but there was no increase in mortality or stroke associated with atrial fibrillation. Conclusion: Post-operative atrial fibrillation incidence in aortic valve replacement is high and correlates with age in patients aged 70 years and older and significantly more pronounced in patients aged 80 years. There was increased length of stay at Intensive Care Unit and hospital, but there was no increase in mortality or stroke. These data are important for planning prophylaxis and early treatment for this subgroup. .

Effect of â-blockers on the risk of atrial fibrillation in patients with acute myocardial infarction

INTRODUCTION: Oral â-blockers improve the prognosis of patients with acute myocardial infarction, while atrial fibrillation worsens the prognosis of this population. The reduction of atrial fibrillation incidence in patients treated with â-blockers could at least in part explain the benefits of this drug. OBJECTIVE: To investigate the effect of â-blockers on the incidence of atrial fibrillation in patients with acute myocardial infarction. METHODS: We analyzed 1401 patients with acute myocardial infarction and evaluated the occurrence or absence of atrial fibrillation, the use of oral â-blockers and mortality during the first 24 hours. RESULTS: a) The use of â-blockers was inversely correlated with the presence of atrial fibrillation (ñ = 0.004; OR = 0.54). b) Correlations with mortality were as follows: 31.5 percent in patients with atrial fibrillation, 9.2 percent in those without atrial fibrillation (ñ < 0.001; Odds Ratio = 4.52), and 17.5 percent in patients not treated with â-blockers and 6.7 percent in those who received the drug (ñ < 0.001; OR = 0.34). c) Adjusted Models: The presence of atrial fibrillation was independently correlated with mortality (OR = 2.48, ñ = 0.002). The use of â-blockers was inversely and independently correlated with mortality (OR = 0.53; ñ = 0.002). The patients who used â-blockers showed a lower risk of atrial fibrillation (OR = 0.59; ñ = 0.029) in the adjusted model. CONCLUSION: The presence of atrial fibrillation and the absence of oral â-blockers increased in-hospital mortality in patients with acute myocardial infarction. Oral â-blockers reduced the incidence of atrial fibrillation, which might be at least partially responsible for the drug's benefit.

Fibrilação atrial no pós-operatório de cirurgia de revascularização do miocárdio: características do perfil clínico associadas a óbitos hospitalares / Postoperative atrial fibrillation following coronary artery bypass graft: clinical factors associated with in-hospital death

OBJETIVO: Identificar fatores associados à maior chance de óbitos hospitalares em pacientes submetidos a revascularização cirúrgica do miocárdio (RM), que tenham apresentado fibrilação atrial (FA) no pós-operatório. MÉTODOS: No período de 2000 a 2003, foi analisada uma série consecutiva de 397 pacientes submetidos a RM que desenvolveram FA no pós-operatório. Esses pacientes foram divididos em dois grupos (G), sendo o G1 formado pelos pacientes que sobreviveram (n=369) e o G2, por aqueles que faleceram na fase hospitalar (n=28). Foram realizados os testes t de Student e do qui-quadrado, sendo p significativo quando < 0,05. RESULTADOS: A análise comparativa entre o G1 e o G2 demonstrou não haver diferença entre os grupos quanto a idade (67,3 ± 8,4 anos vs 69,3 ± 9,6 anos; p = 0,4), sexo masculino (75,9 por cento vs 64,3 por cento; p = 0,1), hipertensão arterial sistêmica (75,3 por cento vs 85,7 por cento; p = 0,2) e insuficiência cardíaca congestiva (17 por cento vs 17 por cento; p = 1). O G2 apresentou maiores taxas de infarto agudo do miocárdio prévio (14,6 por cento vs 28,6 por cento; p = 0,05), fração de ejeção do ventrículo esquerdo < 40 por cento (12,2 por cento vs 32,1 por cento; p = 0,003), acidente vascular encefálico prévio (0,8 por cento vs 17,9 por cento; p = 0,03), intervenção coronariana percutânea prévia (19,5 por cento vs 39,3 por cento; p = 0,01), e revascularização cirúrgica do miocárdio prévia (19,3 por cento vs 35,7 por cento; p = 0,03). CONCLUSÃO: Antecedentes de infarto agudo do miocárdio, RM, intervenção coronariana percutânea, acidente vascular encefálico e déficit ventricular grave foram mais freqüentes no grupo que faleceu na fase hospitalar, sugerindo possível associação entre esses fatores e maior chance de óbito no pós-operatório de RM.

OBJECTIVE: To identify factors associated with a higher likelihood of in-hospital death in patients submitted to coronary artery bypass graft surgery (CABG) who developed atrial fibrillation (AF) postoperatively. METHODS: The authors analyzed data from 397 consecutive patients submitted to CABG that developed AF postoperatively between 2000 and 2003. The patients were divided into 2 groups: group 1 (G1) comprised patients who survived (n=369); and group 2 (G2) comprised patients who died during hospital stay (n=28). Statistical analysis was performed using Student's t test and chi-square test, and p values < 0.05 were considered significant. RESULTS: A comparative analysis between G1 and G2 showed that there was no difference between the groups as regards age (67.3 ± 8.4 versus 69.3 ± 9.6; p = 0.4), male gender (75.9 percent versus 64.3 percent; p = 0.1), systemic arterial hypertension (75.3 percent versus 85.7 percent; p = 0.2) and congestive heart failure (17 percent versus 17 percent; p = 1). Group 2 presented higher rates for previous acute myocardial infarction (14.6 percent versus 28.6 percent; p = 0.05), left ventricular ejection fraction < 40 percent (12.2 percent versus 32.1 percent; p = 0.003), previous cerebrovascular accident (0.8 percent versus 17.9 percent; p = 0.03), previous percutaneous coronary intervention (19.5 percent versus 39.3 percent; p = 0.01) and previous CABG (19.3 percent versus 35.7 percent; p = 0.03). CONCLUSION: Clinical history of acute myocardial infarction, CABG, percutaneous coronary intervention, cerebrovascular accident and severe ventricular dysfunction were significantly more frequent in the group that died during hospital stay, which suggests a possible association of these factors with a higher likelihood of death following CABG.

Criocoagulación de venas pulmonares como tratamiento complementario de la fibrilación auricular en cirugía valvular / Cryoablation of pulmonary veins as complementary treatment of atria I fibrillation in valvular surgery

Background: The Cox MAZE III operation for the treatment of atrial fibrillation (AF) is complex and consumes significant operative time. Cryoablation of the pulmonary veins (CPV) is a simpler alternative for patients that require concomitant valvular surgery. Aim: To evaluate CPV in patients with AF submitted to valvular surgery. Patients and Methods: Twenty one patients had simultaneous valvular surgery and CPV, 81 percent of them had permanent AFfor an average of 5 years. Twenty patients had mitral valve disease. The etiology was rheumatic in 14. Average left atrial diameter was 60 mm. In 7patients the mitral valve was replaced, in 5 it was repaired, in 7 both mitral and aortic valve were replaced, in 1 the mitral valve was repaired and the aortic valve was replaced and in 1 only the aortic valve was replaced. A combined transeptal and superior approach was used for all patients. The CPV was performed after the valvular procedure with cryothermy at -60°C for 2 minutes with two 15 mm cryoprobes applied simultaneously. Results: CPV increased surgical time by 10 to 20 minutes. Operative mortality was 4.8 percent (1 patient). One patient developed a pericardial effusion and another a complete heart block that required a permanent pacemaker. All patients improved their functional class. At the end of an average 10.5 months of follow-up, 50 percent of patients were in normal sinus rhythm and 25 percent persisted in AF. The remaining patients were in some type of regular rhythm. Conclusions: CPV as a complementary procedure in patients with AF undergoing valvular surgery had good results to abate AF. It restored normal sinus rhythm in 50 percent of the cases, with low morbidity and mortality and little increment in surgical time.

Fibrilação atrial crônica, AVC e anticoagulação: sub-uso de warfarina? / Atrial fibrillation, stroke and anticoagulation: under-use of warfarin?

OBJETIVO: Correlacionar acidente vascular cerebral (AVC) cardioembólico em portadores de fibrilação atrial (FA) crônica não valvular, potencialmente evitáveis, previamente acompanhados por cardiologistas, sem restrições ao uso da warfarina, com o grau de absorção das recomendações e limitações publicadas sobre anticoagulação e FA. MÉTODO: Registramos prospectivamente todos os casos de AVC internados em dois hospitais de Joinville.Na presença de FA, foi questionado aos pacientes se sabiam da existência da arritmia, freqüência de visitas a cardiologistas e uso prévio de warfarina. Posteriormente aplicamos um questionário transversal a 11 cardiologistas sobre o FA, anticoagulação e AVC. RESULTADOS: Entre 167 pacientes com AVC, 22 tinham FA prévia e AVC isquêmico. Destes, 15 tinham consultado previamente um cardiologista. Nove pacientes faleceram, sete tiveram alta anticoagulados e seis não receberam warfarina. O questionário evidenciou que 91 por cento dos colegas conheciam as recomendações publicadas, mas somente 54 por cento deles consideravam-nas aplicáveis para pacientes do serviço público. CONCLUSAO: A anticoagulação na FA reduz 68 por cento o risco relativo para AVC/ano. Logo, 11 dos 22 pacientes poderiam ter evitado o evento. Extrapolando a incidência em 1997 e a população atual, podemos considerar que 4 por cento de todos os AVC por ano em Joinville são potencialmente evitáveis.