ABSTRACT
Cardiomiopatia chagásica crônica (CCC) causa arritmias ventriculares e morte súbita, sendo a mais freqüente causa de óbito em muitas áreas endêmicas1,2. A variação circadiana na incidência de arritmias ventriculares e morte súbita difere de acordo com o substrato (p. ex: picos matinais e noturnos na cardiopatia isquêmica e na cardiomiopatia dilatada não-chagásica). Cardioversores-desfibriladores implantáveis de terceira geração (CDI) conseguem registrar o dia e a hora de cada episódio de taquicardia ventricular (TV), permitindo uma análise dos padrões de ocorrência de taquiarritmias. O objetivo deste estudo foi avaliar a variação circadiana da TV espontânea em portadores de CCC tratados com CDI.
Chronic Chagas' cardiomyopathy (CCM) causes ventricular arrhythmias and sudden death, and constitutes the most frequent cause of death in many endemic areas1,2. The circadian variation in the incidence of ventricular arrhythmias and sudden death differs according to the substrate (e.g., morning and evening peaks in ischemic heart disease and non-Chagasic dilated cardiomyopathy). Third generation implantable cardioverter defibrillators (ICDs) have the ability to store the time and date of each ventricular tachycardia (VT) episode, enabling the patterns of ventricular tachyarrhythmia occurrence to be analyzed. The aim of our study was to evaluate the circadian variation of spontaneous VT in recipients of an ICD with CCM.
Subject(s)
Humans , Male , Female , Middle Aged , Circadian Rhythm , Chagas Cardiomyopathy/complications , Defibrillators, Implantable , Tachycardia, Ventricular/etiology , Chronic Disease , Cohort Studies , Chagas Cardiomyopathy/physiopathology , Retrospective Studies , Tachycardia, Ventricular/physiopathology , Tachycardia, Ventricular/therapyABSTRACT
Introducción y objetivos: La elevación de la creatinina es un marcador de riesgo en la insuficiencia cardíaca descompensada (ICD). Nuestro objetivo fue evaluar el rol pronóstico a largo plazo de la detección temprana de deterioro renal (DR), definido por elevación en los niveles de urea y/o creatinina, en pacientes con ICD. Material y métodos: Se incluyeron en forma prospectiva 241 individuos admitidos por ICD. Se seleccionaron los puntos de corte para urea y creatinina al ingreso a través de curva ROC, para la detección de eventos combinados (muerte o rehospitalización por ICD). El seguimiento medio fue de 366 ± 482 días. Resultados: La edad media fue 65,4 ± 11,6 años (63,8% hombres, 42,3% etiología isquémica) y la incidencia de eventos fue de 107. El área bajo curva ROC de urea y creatinina para la predicción de eventos fue de 0,59 y 0,57. Los puntos de corte, sensibilidad y especificidad fueron: urea 55 mg/dL, 57% y 63%; y creatinina 1,17 mg/dL, 58% y 62%, respectivamente. El DR se identificó en 144 (60,4%) sujetos, 82 con ambos marcadores elevados, 29 sólo con creatinina elevada y 33 sólo con urea elevada. En el grupo con DR fue más frecuente el diagnóstico previo de ICD (89 vs 78%, p=0,041) y la hipoperfusión periférica (12,5 y 4,1%, p=0,020), tuvieron menor fracción de eyección del ventrículo izquierdo (FEVI) (36,4±17,2% y 41,1±19,6%, p=0,05) y mayor nivel de pro-BNP (8681±9010 pg/l y 2943±269 pg/l, p<0,001). La supervivencia libre de rehospitalización por ICD a 18 meses en aquellos con y sin DR fue 35 y 60% (p=0,0086), y las variables asociadas con evolución adversa fueron DR (HR=1,8; IC 95% 1,1-2,7) y diagnóstico previo de ICD (HR=1,9; p<0,001; IC 95% 1,1-3,5). Conclusión: El uso combinado de urea y creatinina permite incrementar la detección temprana de DR en pacientes con ICD. Este hallazgo fue un fuerte predictor de eventos a largo plazo.
Background: Increased level of creatinine is a powerful risk marker in decompensated heart failure (DHF). Our objective was to evaluate the long-term prognostic role of early detection of renal dysfunction (RD), defined by abnormal levels of urea and/or creatinine, in patients with DHF. Patients and methods: Two hundred and forty-one patients admitted for DHF were prospectively included. The cut-off of urea and creatinine were selected using ROC curves for predicting combined events (death or rehospitalization for DHF). The mean follow-up was 366±482 days. Results: The mean age were 65.4±11.6 years (64% male, 42.3% ischemic etiology), and 44.4% had events. The area under ROC curves to predicting events for urea and creatinine was 0.59 and 0.57, respectively. The cut-off, sensitivity and specificity were: urea 55 mg/dL, 57% and 63%; creatinine 117 mg/dL, 58% and 62%, respectively. RD was identified in 144 (60.4%) subjects, 82 had elevated both markers, 29 with only increased levels of creatinine, and 33 with only abnormal levels of urea. RD groups had more frequently a previous diagnosis of HF (89 vs 78%, p=0.041) and peripheral hypoperfusion (12.5 vs 4.1%, p=0.020), and they showed lower LVEF (36.4±17.2% vs 41.1±19.6%, p=0.05) and higher pro-BNP (8.681±9010 pg/mL vs 2943±2690 pg/ mL, p<0.001) than those without RD. Eighteen-month free-DHF rehospitalization survival in patients with and without RD was 35% and 60% (p=0.0086). The variables significantly associated with events were RD (1.8, p<0.001; CI 95%=1.1-2.7) and previous diagnosis of HF (HR=1.9, CI 95%=1.1-3.5). Conclusion: The combined use of urea and creatinine improve the early detection of RD in patients with DHF. This finding was a strong long-term prognostic predictor.