OBJECTIVES: The red blood cell distribution width has been associated with an increased risk of cardiovascular events. In the present study, we assessed the relationship between red cell distribution width values and cardiac troponin I levels in patients admitted with non-ST-elevation acute coronary syndrome. METHODS: We analyzed blood parameters in 251 adult patients who were consecutively admitted to the intensive coronary care unit with non-ST-elevation acute coronary syndrome over a 1-year period. For all patients, a baseline blood sample was collected for routine hematological testing. Cardiac troponin I was measured at baseline and after 6 h. The patients were diagnosed with non-ST-elevation myocardial infarction or unstable angina based on the elevation of cardiac troponin I levels. RESULTS: The red cell distribution width was higher in the group with non-ST-elevation myocardial infarction compared with the patient group with unstable angina (14.6±1.0 vs 13.06±1.7, respectively; p = 0.006). Coronary thrombus was detected more frequently in the group of patients with non-ST-elevation myocardial infarction than in the patients with unstable angina (72% vs 51%, respectively; p = 0.007). Using receiver operating characteristic curve analysis for the prediction of non-ST-elevation myocardial infarction based on the red cell distribution width, the area under the curve was 0.649 (95% confidence interval: 0.546-0.753; p = 0.006), suggesting a modest model for the prediction of non-ST-elevation myocardial infarction using the red cell distribution width. At a cut-off value of 14%, the sensitivity and specificity of the red cell distribution width were 73% and 59%, respectively. Additionally, the red cell distribution width was positively correlated with cardiac troponin I (r = 0.19; p = 0.006). CONCLUSION: A greater baseline red cell distribution width value was associated with myocardial injury and elevated cardiac troponin I levels in non-ST-elevation acute coronary syndrome. Therefore, the red cell distribution width could be considered for risk stratification of acute coronary syndrome patients admitted to emergency departments.

Fundamento: A hipertensão arterial é o fator de risco mais prevalente e modificável para a fibrilação atrial. A sobrecarga de pressão no átrio esquerdo induz alterações fisiopatológicas que ocasionam alterações na função contrátil e nas propriedades elétricas. Objetivo: Nesse estudo, o objetivo foi avaliar a função do átrio esquerdo em pacientes hipertensos para determinar a associação entre a função atrial esquerda e a fibrilação atrial paroxística (FAP). Método: Foram estudados 57 pacientes hipertensos (idade: 53 ± 4 anos, fração de ejeção do ventrículo esquerdo: 76 ± 6,7%), incluindo 30 pacientes consecutivos com FAP e 30 indivíduos de controle pareados por idade. Os volumes do átrio esquerdo (AE) foram medidos através do método biplano de Simpson modificado. Foram determinados três tipos de volume do AE: volume máximo do AE (AEVmax), contração atrial prematura do AE (AEVpreA) e volume mínimo do AE (AEVmin). Foram calculadas as funções de esvaziamento do AE. Volume total de esvaziamento do AE = AEVmax - AEVmin e a FEtotal do AE = (AEVmax - AEVmin)/AEVmax, volume de esvaziamento passivo do AE = AEVmax-AEVpreA, e a FE do AE = (AEVmax - AEVpreA)/AEVmax, o volume de esvaziamento ativo do AE = AEVpreA- AEVmin e a FE ativa do AE = (AEVpreA - AEVmin)/AEVpreA. Resultados: O período hipertenso é maior no grupo de hipertensos com FAP. O AEVmax aumentou significativamente no grupo de hipertensos com FAP quando comparado ao grupo de hipertensos sem FAP (p = 0,010). A FEAE diminuiu significativamente no grupo de hipertensos com FAP em comparação com o grupo de hipertensos sem FAP (p = 0,020). A' diminuiu no grupo de hipertensos com FAP quando comparado com hipertensos sem FAP (p = 0,044). Conclusão: O volume aumentado do AE e função de esvaziamento ativa do AE prejudicada foram associados com a FAP em pacientes hipertensos não tratados. Um período hipertenso mais longo está associado com a FAP.

Background: Hypertension is the most prevalent and modifiable risk factor for atrial fibrillation. The pressure overload in the left atrium induces pathophysiological changes leading to alterations in contractile function and electrical properties. Objective: In this study our aim was to assess left atrial function in hypertensive patients to determine the association between left atrial function with paroxysmal atrial fibrillation (PAF). Method: We studied 57 hypertensive patients (age: 53±4 years; left ventricular ejection fraction: 76±6.7%), including 30 consecutive patients with PAF and 30 age-matched control subjects. Left atrial (LA) volumes were measured using the modified Simpson's biplane method. Three types of LA volume were determined: maximal LA(LAVmax), preatrial contraction LA(LAVpreA) and minimal LA volume(LAVmin). LA emptying functions were calculated. LA total emptying volume = LAVmax−LAVmin and the LA total EF = (LAVmax-LAVmin )/LAVmax, LA passive emptying volume = LAVmax− LAVpreA and the LA passive EF = (LAVmax-LAVpreA)/LAVmax, LA active emptying volume = LAVpreA−LAVmin and LA active EF = (LAVpreA-LAVmin )/LAVpreA. Results: The hypertensive period is longer in hypertensive group with PAF. LAVmax significantly increased in hypertensive group with PAF when compared to hypertensive group without PAF (p=0.010). LAAEF was significantly decreased in hypertensive group with PAF as compared to hypertensive group without PAF (p=0.020). A' was decreased in the hypertensive group with PAF when compared to those without PAF (p = 0.044). Conclusion: Increased LA volume and impaired LA active emptying function was associated with PAF in untreated hypertensive patients. Longer hypertensive period is associated with PAF.