[Clinical characteristics, complications and mortality in 506 patients with infective endocarditis and determinants of survival rate at 10 years]. / Endocarditis infecciosa: características clínicas, complicaciones y mortalidad en 506 pacientes y factores pronósticos de sobrevida a 10 años (1998-2008). Estudio cooperativo nacional en endocarditis infecciosa en Chile (ECNEI-2).

BACKGROUND: Rates of morbidity and mortality in Infective Endocarditis (IE) remain high and prognosis in this disease is still difficult and uncertain. AIM: To study IE in Chile in its active phase during inpatient hospital stay and long term survival rates. MATERIAL AND METHODS: Observational prospective national cohort study of 506 consecutive patients included between June 1,1998 and July 31, 2008, from 37 Chilean hospitals (secondary and tertiary centers) nationwide. RESULTS: The main findings were the presence of Rheumatic valve disease in 22.1 % of patients, a history of intravenous drug abuse (IVDA) only in 0.7%, the presence of Staphylococcus aureus in 29.2% of blood cultures, negative blood cultures in 33.2%, heart failure in 51.7% and native valve involvement in 86% of patients. Echocardiographic diagnosis was achieved in 94% of patients. Hospital mortality was 26.1% and its prognostics factors were persisting infection (Odds ratio (OR) 6.43, Confidence Interval (CI) 1.45-28.33%), failure of medical treatment and no surgical intervention (OR 48.8; CI 6.67-349.9). Five and 10 years survival rates were 75.6 and 48.6%, respectively. The significant prognostic factors for long term mortality, determined by multivariate analysis were the presence of diabetes, Staphylococcus aureus infection, sepsis, heart failure, renal failure and lack of surgical treatment during the IE episode. CONCLUSIONS: The microbiologic diagnosis of IE must be urgently improved in Chile. Mortality rates are still high (26.1%) partly because of a high incidence of negative blood cultures and the need for more surgical valve interventions during in-hospital period. Long term prognostic factors for mortality should be identified early to improve outcome.

Endocarditis infecciosa: características clínicas, complicaciones y mortalidad en 506 pacientes y factores pronósticos de sobrevida a 10 años (1998-2008). Estudio cooperativo nacional en endocarditis infecciosa en Chile (ECNEI-2) / Clinical characteristics, complications and mortality in 506 patients with infective endocarditis and determinants of survival rate at 10 years

Background: Rates ofmorbidity and mortality in Infective Endocarditis (IE) remain high and prognosis in this disease is still difficult and uncertain. Aim: To study IE in Chile in its active phase during inpatient hospital stay and long term survival rates. Material and Methods: Observational prospective national cohort study of 506 consecutive patients included between June 1,1998 and July 31, 2008, from 37 Chilean hospitals (secondary and tertiary centers) nationwide. Results: The main findings were the presence of Rheumatic valve disease in 22.1 % of patients, a history of intravenous drug abuse (IVDA) only in 0.7%, the presence of Staphylo-coccus aureus in 29.2% of blood cultures, negative blood cultures in 33.2%, heart failure in 51.7% and native valve involvement in 86% ofpatients. Echocardiographic diagnosis was achieved in 94% of patients. Hospital mortality was 26.1% and its prognostics factors were persisting infection (Odds ratio (OR) 6.43, Confidence Interval (CI) 1.45-28.33%), failure of medical treatment and no surgical intervention (OR 48.8; CI 6.67-349.9). Five and 10 years survival rates were 75.6 and 48.6%, respectively. The significant prognostic factors for long term mortality, determined by multivariate analysis were the presence of diabetes, Staphylococcus aureus infection, sepsis, heart failure, renal failure and lack of surgical treatment during the IE episode. Conclusions: The microbiologic diagnosis of IE must be urgently improved in Chile. Mortality rates are still high (26.1%) partly because of a high incidence of negative blood cultures and the need for more surgical valve interventions during in-hospital period. Long term prognostic factors for mortality should be identified early to improve outcome.

[Infectious endocarditis: morbi-mortality in Chile. Results of the National Cooperative Study of Infective Endocarditis (1998-2002)]. / Endocarditis infecciosa: morbimortalidad en Chile. Resultados del Estudio Cooperativo Nacional de Endocarditis Infecciosa (ECNEI: 1998-2002).

BACKGROUND: Infective endocarditis is a severe condition, with a mortality that fluctuates between 16 and 25% in the Metropolitan area of Chile. AIM: To perform a prospective assessment of clinical and microbiological features of patients with infective endocarditis in Chile. MATERIAL AND METHODS: Collaborative study of regional hospitals in the whole country and teaching hospitals in Santiago. Patients with a possible or definitive infective endocarditis, according to Duke's criteria, were included in the protocol and a structured data entry form was completed. RESULTS: Three hundred twenty one patients (65% male, mean age 49 +/- 16.5 years) were studied. According Duke's criteria, 89% had a definitive and 11% a possible endocarditis. The subacute form occurred in 64% of patients. The most frequent predisposing cardiopathies were rheumatic in 25%, prosthetic valves in 15% and congenital in 13%. There was no evidence of cardiopathy in 20%. Twenty percent of patients were on hemodialysis, 11% were diabetic and only one patient abused intravenous drugs. The most frequent complication was cardiac failure in 59% of cases, followed by renal failure in 32% and embolism in 28%. The most frequent causing organism was coagulase positive Staphylococcus in 35%. Blood cultures were negative in 28% of cases from the metropolitan region, in 56% of cases from the north and 38% of cases from the south. Echocardiographic diagnosis was done in 92% of cases. Aortic valve was involved in 42% and mitral valve in 29%. Successful antimicrobial treatment was achieved in 59% of patients. Thirty five percent of patients were subjected to surgical procedures with a 78% survival. Overall mortality was 29%. Univariate analysis identified sepsis, an age over 60 years and the presence of cardiac or renal failure as prognostic indicators of mortality. On multivariate analysis, the identified prognostic indicators were the presence of sepsis, renal failure, mitroaortic involvement associated to combined surgery and failure of antimicrobial treatment not associated to surgery. CONCLUSIONS: Subacute form is the most common presentation of infective endocarditis and rheumatic valve disease is the most common underlying cardiac lesion. Intravenous drugs users infective endocarditis is exceptional in Chile. The most frequent causing agent is coagulase positive Staphylococcus and the most frequent complication is cardiac failure. Surgical and overall mortality were 22 and 29% respectively. Sepsis, renal failure, combined surgical procedures, failure of medical treatment were identified as prognostic indicators of mortality.

Amiodarona en alta dosis de carga oral única: parámetros farmacocinéticos en pacientes sometidos a cirugía coronaria / High loading dose of amiodarone: pharmacokinetics in patients undergoing coronary

Antecedentes: Amiodarona (A) es la droga antiarrítmica más utilizada en la actualidad. No obstante, algunos aspectos de su compleja farmacología son todavía poco conocidos en ciertos grupos de pacientes. Objetivo: Estudiar los parámetros farmacocinéticos de A después de una alta dosis de carga oral en pacientes (P) sometidos a cirugía coronaria. Métodos: Cuarenta y tres P sometidos a cirugía coronaria recibieron una dosis oral de 30 mg/kg en dosis fraccionada como tratamiento profiláctico de arritmias en el post operatorio. Las concentraciones sanguíneas de la droga fueron medidas a tiempos sucesivos, por HPLC, hasta las 96 h de su administración. En base a la curva obtenida de concentración sanguínea vs tiempo, los parámetros farmacocinéticos fueron calculados mediante un programa computacional independiente del modelo compartimental. Resultados: La concentración sanguínea de A alcanzó un valor máximo de 2,3 +/- 1,5µg/ml a las 10 h de la administración de la droga. Posteriormente, se observó un descenso gradual con un valor de 0,4 +/- 0,1 µg/ml a las 96h de administración. Los parámetros farmacocinéticos obtenidos fueron: Vida media 29,1 +/- 11,3h; Area bajo la curva 0’96 63,6 +/- 22,3 (µg/ml)h; Clearance total 6,1 +/- 2,2 ml/min/kg; Volumen de distribución 15,6 +/- 5,4 L/kg. Conclusiones: La farmacocinética de A presenta diferencias con lo encontrado en estudios de dosis única en otros grupos de pacientes. El presente trabajo puede servir para esquemas de dosificación menos empíricos de A.

Background: Amiodarone is currently the most commonly used antiarrhythmic drug. However, some aspects of its complex pharmacokinetics in particular groups of patients are not well known. Aim: to study the pharmacokinetics of amiodarone after a high loading oral dose in patients undergoing coronary revascularization surgery. Methods: Forty three patients operated on for coronary artery disease received oral dose amiodarone, 30mg/Kg, in a fractioned dose as a prophylactic antiarrhythmic medication following surgery. Blood amiodarone concentration was measured at successive intervals for 96 hr. A software based on a non compartmental model was used to determine pharmacokinetic parameters. Results: Maximal blood concentration of amiodarone was 2.3 +/-1.5µg/ml 10hr after drug administration. A subsequent gradual decrease of amiodarone blood level was observed, down to 0.4 +/- 0.1µg/ml at 96hr post drug administration. The half-life time was 29.1 +/- 11.3hr. The area under de 0 to 96hr curve was 63.6 +/- 22.3µg/ml.Total clearance was 6.1 +/- 2.2 ml/min/kg. The distribution volume was 15.6 +/- 5,4 L/kg. Conclusion: Pharmacokinetics of amiodarone differs from that obtained following a single dose in other groups of patients. The data provided may be used to determine more objective amiodarone dosing schemes.

Terapia de resincronización ventricular en pacientes portadores de marcapasos definitivo e insuficiencia cardiaca avanzada / Ventricular resynchronization therapy in patients with a previous pacemaker for the management of advanced refractory heart failure

Antecedentes: La Terapia de Resincronización Ventricular (TRV) es un procedimiento aceptado en el tratamiento de la Insuficiencia cardiaca (IC) avanzada y retardo de conducción intraventricular. Existe escasa información de esta terapia en pacientes con IC y Marcapasos (MP) previo. Objetivos: Evaluar el impacto de la TRV en pacientes con MP previo e IC refractaria. Pacientes y método: Entre junio 2000 y agosto 2004, 15 pacientes con MP e IC avanzada, edad 60,9 + 15 años, 12 hombres, fueron sometidos a TRV. En 2 de ellos se efectuó como medida de salvataje y puente al transplante cardíaco. Resultados: En todos se logró implantar un electrodo epicárdico en VI vía seno coronario. Dos pacientes tuvieron complicaciones: 1 neumotórax, 1 desplazamiento de electrodo y posterior fractura del mismo. En el seguimiento de 15 meses hubo disminución del DDVI (68mm versus 63mm, p<0,005) y aumento de la FE (22 por ciento versus 32 por ciento, p<0,0001). Antes de la TRV el 86 por ciento de los pacientes estaba en CF III-IV, y posteriormente el 77 por ciento estaba en CF III (p<0,005). Fallecieron 4 pacientes: 2 por neumonía y 2 por IC refractaria. De los pacientes en que la TRV fue efectuada como puente al transplante, éste se logró realizar en ambos. Conclusiones: La TRV es factible en pacientes con MP previo e IC refractaria, con una baja tasa de complicaciones, y se asocia a una mejoría clínica y de la función de VI significativa. En casos seleccionados podría ser una medida útil como puente al transplante cardíaco.