Endocarditis infecciosa: morbimortalidad en Chile: resultados del estudio cooperativo nacional de endocarditis infecciosa, ECNEI, 1998-2002 / Mortality and complications of infective endocarditis in Chile: results of the national cooperative study of infective endocarditis, 1998-2002

Infective endocarditis is a severe condition, with a mortality that fluctuates between 16 and 25 percent 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 percent male, mean age 49ñ16.5 years) were studied. According Duke's criteria, 89 percent had a definitive and 11 percent a possible endocarditis. The subacute form occurred in 64 percent of patients. The most frequent predisposing cardiopathies were rheumatic in 25 percent, prosthetic valves in 15 percent and congenital in 13 percent. There was no evidence of cardiopathy in 20 percent. Twenty percent of patients were on hemodialysis, 11 percent were diabetic and only one patient abused intravenous drugs. The most frequent complication was cardiac failure in 59 percent of cases, followed by renal failure in 32 percent and embolism in 28 percent. The most frequent causing organism was coagulase positive Staphylococcus in 35 percent. Blood cultures were negative in 28 percent of cases from the metropolitan region, in 56 percent of cases from the north and 38 percent of cases from the south. Echocardiographic diagnosis was done in 92 percent of cases. Aortic valve was involved in 42 percent and mitral valve in 29 percent. Successful antimicrobial treatment was achieved in 59 percent of patients. Thirty five percent of patients were subjected to surgical procedures with a 78 percent survival. Overall mortality was 29 percent. 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. The most frequent causing agent is coagulase positive Staphylococcus...

Hipercoagulabilidad en fibrilación auricular y su relación con factores de riesgo para embolia sistémica / Hypercoagulable state in atrial fibrillation and its relationship with risk factors for systemic embolism

Background: Atrial fibrillation is associated to a high risk of systemic embolism and to hypercoagulability. Aim: To evaluate the activation of the coagulation cascade through determinations of the thrombin-antithrombin complex in patients with atrial fibrillation and to correlate this data with the clinical and echocardiographic risk factors for systemic embolism. Patients and Methods: In 53 patients with atrial fibrillation plasma levels of the thrombin-antithrombin complex were determined on admission to a coronary care unit and 30 days later. Using a univariate and multiple regression analysis, the association basal thrombin-antithrombin with the duration of the arrhythmia, age over 70 years, previous use of antiplatelet agents, history of hypertension, mitral valve disease, diabetes, heart failure, previous systemic embolism, left atrial diameter and the presence of spontaneous contrast echo or thrombus in the left atrial appendage, was studied. Results: Basal thrombin-antithrombin values were 40.1ñ69 mg/L (Median 8.34 [3.0-47.5]) compared to 2.7ñ3.3 mg/L in healthy controls (p <0.001). No significant correlation was found between activation of the coagulation cascade and risk factors for systemic embolism. There were no significant differences in thrombin-antithrombin values between patients with chronic or paroxysmal atrial fibrillation (29.5ñ43 mg/L and 49.4ñ83 mg/L respectively). Mean thrombin-antithrombin values in patients under antiplatelet agents were lower than in those without treatment (17.3ñ43 vs 66.8ñ127 mg/L; p=0.018). Conclusions: The activation of the coagulation cascade in patients with atrial fibrillation was confirmed. However, no association of this activation with well known clinical and echocardiographic risk factors for systemic embolism, was found. Previous antiplatelet treatment prevented a higher activation of the coagulation cascade

Experiencia de 36 años con marcapasos implantables: un análisis histórico / A 36 year experience with implantable pacemakers

Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificaci-n de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74 percent from 1988 to 1998. Complication rate was 42 percent in the 1963-1976 study period, it decreased to 10.6 percent in the 1977-1987 study period, and to 5.6 percent by 1988-1998. Only two patients died during surgery in the study period (0.08 percent). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52 percent at ten years, 33 percent at 15 years, and 21 percent at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures

Cirugía de la insuficiencia mitral isquémica / Surgery for ischemic mitral regurgitation

Background. Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, nowithstanding a relatively high mortality rate. Objectives. To evaluate the results of mitral valve replacement or repair in patients with IMR. Patients and methods. Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8 percent of surgical procedures on the mitral valve. Results. Mean age was 67 ñ 9 years. Surgery was performed urgently in 19 patients (66,5 percent). NYHA functional class was 3.4 ñ 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83 percent) had concomitant myocardial revascularization. Overall surgical mortality was 24 percent; 26 percent for mitral replacement and 13 percent for mitral valve repair (p=0.215). On follow up of 26ñ33 months, one year survival was 76ñ0.8 percent and 5 years survival was 59ñ12 percent. Excluding in hospital mortality, survival was 100 percent at one year and 78ñ14 percent at 5 years. Functional class improved in all survivors, to 1.4ñ0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58 percent, 1+ MR in 17 percent and 2+ MR in 25 percent. Conclusion. In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease

Reoperaciones coronarias: análisis retrospectivo de 16 años de experiencia / Coronary artery bypass grafting reoperation: a 16 years retrospective analysis

Background: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. Aim: To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors. Patients and methods: 214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied. Results: Mean age was 64.2 years (range 42-79 years), 202 (94.4 per cent) were male and 12 (5.6 per cent) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4,6 per cent) were emergency surgeries. Overall operative mortality was 5.6 per cent (11 deaths) and in 5 patients (3.4 per cent) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p=0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p=0.02) and moderate or severe left ventricular failure (p=0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9 per cent, a 10 years survival rate of 73.1 per cent and a 15 years survival rate of 53.4 per cent. Moderate or severe left ventricular failure (p <0.0001) and emergency surgeries (p=0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p=0.01) and peripheral vascular disease (p=0.01) as predictors of decreased late survival. Conclusions: Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality

Endocarditis infecciosa: análisis de 261 casos y resultados del tratamiento con un enfoque multidisciplinario / Infectious endocarditis: short and long term results in 261 cases managed by a multidisciplinary approach

Background: Early diagnosis, an effective treatment and prompt recognition of complications are essential to improve the prognosis of infective endocarditis (IE) Aim: To report the results of a multidisciplinary approach to diagnosis and management of patients with IE at the Universidad Cat-lica de Chile Hospital. Patients and methods: The clinical history, diagnosis, treatment and outcome of 261 episodes (Duke criteria) of IE admitted between January 1980 and January 1999 were analyzed. These included 185 episodes of native, 73 of prosthetic valve and 3 of nonvalvular IE. Results: Sixty nine percent of patients were men and the mean age was 49 ñ 16 years. Seventy five percent had a definite diagnosis of IE (Duke). S. viridans, staphylococci and enterococci together constituted 85 percent of the isolated bacterial strains. Twenty seven had culture-negative IE, related to a high incidence of antibiotic therapy prior to diagnosis. Transesophageal echocardiography was performed in 102 cases and it detected vegetations in 91 percent of aortic and 96 percent of mitral IE, rupture or prosthesis dehiscence in 67 percent of aortic and 52 percent of mitral IE and abscesses in 51 percent of aortic and 15 percent of mitral IE. Fifty one percent developed heart failure and 34 percent had embolic events. S. aureus IE was associated to a higher incidence of embolic events, complications which contraindicated surgery and increased mortality rate (27 percent). Of all patients, 40 percent were treated exclusively with antibiotics, 52 percent were operated on and 8 percent had surgical indication but were nonoperable because of serious complications. The overall mortality was 16.3 percent: 13 percent in the medical, 9 percent in the surgical and 81 percent in the non-operable groups. The type of treatment and mortality rates did not differ between IE of native valves and prosthetic valves. Long term follow up showed survival rates of 73 percent at 5 years and 66 percent at 10 years. Conclusion: A multidisciplinary approach may be very helpful to improve the prognosis of IE

Actividad plasmática de la enzima convertidora de angiotensina I en población chilena normal y relación con el genotipo inserción/deleción de la enzima convertidora de angiotensina / Plasma activity of angiotensin I converting enzyme in a normal chilean population and it relation to de I/D polymorphism

El objetivo del estudio fue estimar la prevalencia de los distintos alelos del polimorfismo del gen de la enzima convertidora de angiotensina (ECA), inserción/deleción (I/D) y simultáneamente la actividad de ECA plasmática (pl) asociada en población sana chilena normotensa. 117 sujetos sanos normotensos (entre 45 y 60 años, de nivel socioeconómico medio, no obesos ni diabéticos) fueron seleccionados de un estudio poblacional sobre prevalencia de factores de riesgo de enfermedades crónicas. Las frecuencias de los alelos I y D fueron 0,57 y 0,43 respectivamente. La actividad de ECApl fue en promedio 15,3ñ3,9 U/mL. Comparado con sujetos con genotipo II, la actividad de ECApl fue significativamente mayor en sujetos con genotipo ID y DD sin diferencias entre ellos. No se observó correlación entre actividad de ECApl y masa VI en ningún sexo ni en los distintos genotipos. El análisis de regresión lineal multivariado (que usó masa VI e índice de masa VI como variables dependientes mostró efectos independientes (p<0,05) del sexo (mayor masa VI en varones) y de la presión diastólica, pero no del genotipo DD. En conclusión, en esta población la presencia del alelo D del gen de la ECA determina mayor actividad de ECA circulante, lo cual podría estar asociado a mayor morbilidad cardiovascular. En esta población sana normotensa, el sexo masculino y la presión diastólica, pero no la presencia del alelo D, están asociados a mayor masa VI

Cardiopatía, embarazo y tratamiento anticoagulante / Anticoagulant therapy in pregnant women with mechanical valve prosthesis and/or heart diseases

Pregnancy is a hypercoagulable state. Some women with cardiac disease and mechanical valve prosthesis are at increased risk of arterial thromboembolic phenomena. These women are maintained on oral anticoagulants and require effective permanent prophylaxis during pregnancy. The use of oral anticoagulants during pregnancy is controversial because of the risks of embriopathy (Chondrodysplasia punctata) in fetuses who are exposed to coumarin between the 6th and 9th week of gestation, the risk of neurological disorders all through pregnancy, and a higher incidence of abortion and stillbirths. The exact incidence of these complications is unknown. Most of this information comes from North American reports, when much higher mean daily doses of coumarin were administered, and they were probably overemphasised2. Reports from Europe, Asia and our own, show that both embriopathy and central nervous system malformations are probably dose-related and that the risks of abnormality to the fetus are small3-8. The ACC Antithrombotic Consensus (1998) recommends the use of subcutaneous heparin all through pregnancy or until the 13th week of gestation. Heparin does not cross the placenta, however there is a higher risk of maternal bleeding, abortion and stillbirths. With the use of small dose of heparin and of therapeutic heparin doses there is a risk of prosthesis thrombosis. Anticoagulant treatment of patients with prosthetic heart valves during pregnancy remains controversial. Subcutaneous heparin prophylaxis is feasible but the use of well controlled oral anticoagulants appear to offer lower risks of maternal and fetal complications

Resultados alejados de la cirugía reconstructora de la insuficiencia mitral / Long term results of reconstructive surgery for mitral insufficiency

Background: Surgical repair is the procedure of choice for mitral insufficiency since it preserves better left ventricular structure and function. Aim: To assess the long term clinical and echocardiographic results of mitral valve reconstructive surgery. Material and methods: A review of clinical and echocardiographic data of 68 patients (34 male, age range 17 to 82 years), subjected to surgical mitral valve repair between december 1991 and march 1998. Preoperative functional capacity of these patients was 2.96 ñ 0.7. Surgical repair was assessed using transesophagic echocardiography in all subjects. Results: The etiology of mitral insufficiency was degenerative in 43 patients, rheumatic in 10, infectious in 6, ischemic in 5 and miscellaneous in 4. The most frequent pathological findings were dilatation of the mitral ring in 42 percent of patients, chordae tendinae rupture in 32 percent and enlargement in 24 percent. A mitral anuloplasty was done in 90 percent of patients, a cuadrilateral resection of posterior leaflet in 52 percent and chordae tendinae transference in 12 percent. An additional surgical procedure was done in 34 percent of subjects. Three patients died during hospitalization (4.4 percent). During the follow up of 36.5 ñ 22.3 months, five patients died and one required a mitral valve replacement. The actuarial survival probability was 95.3 ñ 2.6 percent at one year and 83.5 ñ 6.5 percent at five years. The reoperation free survival was 100 percent at one year and 97.4 ñ 2.5 percent at five years. At the end of follow up the functional capacity improved to 1.25 ñ 0.4. echocardiography showed absence of mitral insufficiency in 48.4 percent of patients, minimal, mild and moderate insufficiency in 35.5, 14.5 and 1.6 percent of patients respectively. Conclusions: Surgical valve reconstruction in mitral insufficiency has satisfactory long term results and should be the procedure of choice for eligible patients

Mini esternotomía en cirugía valvular / Minimally invasive sternotomy for valvular heart surgery

Antecedentes: desde mediados de la presente década se han propuesto distintos accesos mínimamente invasivos en cirugía cardiovascular, entre ellos la miniesternotomía. Objetivo: presentar nuestra experiencia inicial en cirugía valvular a través de miniesternotomía. Pacientes: entre octubre 1997 y diciembre 1998, se efectuó un reemplazo valvular aórtica y en otra un reemplazo valvular mitral, a través de una miniesternotomía media en "J". Nueve pacientes eran hombres. El promedio de edad fue de 53,6 años (29-73). Todos los pacientes fueron operados con monitorización ecocardiográfica transesofágica. Técnica quirúrgica. Se efectuó una esternotomía media en "J" en el 3º o 4º espacio intercostal derecho con una incisión cutánea menor a 10 cm en todos los casos. Para el retorno arterial se canuló la aorta ascendente y para el drenaje venoso, la orejuela derecha con una cánula única. La protección miocárdica se efectuó con cardioplegia cristaloide infundida en forma anterógrada y/o retrógrada a 4ºC. El drenaje de las cavidades izquierdas se efectuó con un catéter introducido a través de la vena pulmonar superior derecha. Los reemlazos valvulares aórticos se efectuaron a través de una aortotomía oblicua y el reemplazo valvular mitral a través de una auriculotomía izquierda superior...

Ritmo cardíaco y embolias sistémicas en la evolución alejada de pacientes con fibrilación auricular paroxística no valvular / Cardiac rhythm and systemic emboli during long term follow up of patients with non-valvular paroxysmal atrial fibrillation

Background: Paroxysmal atrial fibrillation may predispose to systemic embolism. There is little information about the evolution of cardiac rhythm and the occurrence of new embolic events in these patients. Aim: To report the results of a long term follow up of patients with paroxysmal atrial fibrillation. Patients and methods: Patients consulting for non valvular paroxysmal atrial fibrillation were followed for a mean period of 5 years. An EKG, 2D echocardiogram and brain CT scans were performed on admission and at the end of the follow up period to all patients. Results: Sixty eight patients aged 65 ñ 1.5 years were studied. Thirty two had an idiopathic atrial fibrillation, 28 had a history of mild hypertension and 8 had a history of coronary artery disease. Evidence of systemic emboli was found in 17 patients at entry (to the brain in 14 patients). During the follow up 87 per cent of patients required antiarrhythmics, 27 per cent were anticoagulated and 28 per cent received aspirin. Five patients had new embolic episodes. Of these, four had a history of prior embolism. Forty one percent of patients continued in sinus rhythm and remained asymptomatic, 32 per cent had at least one recurrence of paroxysmal atrial fibrillation and nine patients evolved to chronic atrial fibrillation. Five patients required a permanent pacemaker due to symptomatic bradycardia. Conclusions: Most patients with non valvular paroxysmal atrial fibrillation remain in sinus rhythm but one third have recurrences of the arrhythmia. A main risk factor for embolism is the history of previous embolic episodes

Cirugía coronaria: veinte años de seguimiento / Results of coronary surgery: a 20 years experience

Background: Since the first surgical coronary revascularization done in Chile in 1971, 5000 such procedures bave been performed. Aim: To assess the long term results of coronary revascularization surgery in our institution and to identify prognostic factors. Patients and methods: Five groups of 100 patients each, composed by the first consecutive patients subjected exclusively to coronary bypass surgery in the years 1975, 1980, 1985, 1990 and 1995 were retrospectively studied. Results: Mean age of Patients increased from a median of 52 years old in 1975 to 62 yean old in 1995. No changes in the frequency of diabetes, hypertension, high serum cholesterol or prvious mycardial infarction were observed. There was an increase in the Proportion of patients with a recent (< 30 days) infarction that were operated along time. Seventy percent of patients had triple vessel disease or LMT and this proportion did not change. The number of grafts per patients increased form 1.9 to 3.4 and the use of arterial conduits from 0.18 to 0.81. Perioperative mortality remained constant and was 1.6 percent. Follow up information was obtained for 93 percent of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93ñ1, 82ñ2, 62ñ3 and 41ñ4 percent respectively. Ninety eight ñO.7, 89ñ2, 73ñ4 and 65ñ5 percent of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninety seven ñl, 94ñ2, 76ñ4 and 47ñ7 percent of patients remained free of a new operation. Stepwise logistical regression analysis identified as bad Prognostic factors, in decreasing order: cardiac failure, diabetes, smoking, hypercholesterolemia and age at the moment of operation. Conclusions: Coronary artery bypass surgery provides good and long lasting clinical improvement. The prognosis of patients is influenced by the presence of cardiac failure, some well known coronary risk factors and age at the moment of operation

Tromboendarterectomía pulmonar: tratamiento quirúrgico del tromboembolismo pulmonar crónico bajo paro circulatorio con hipotermia profunda en un caso / Pulmonary thromboendarterectomy: surgical treatment of chronic pulmonary thromboembolism under circulatory arrest and with deep hypothermia in 1 case

Pulmonary thromboendarterectomy under circulatory arrest and deep hypothermia is presently a curative treatment for pulmonary hypertension secondary to chronic pulmonary artery thromboembolic occlusion, but is still not frequently performed around the world. We report here the first successful pulmonary thromboendarterectomy under circulatory arrest performed in Chile. The patient was a 37 years old white man, high school teacher, with a 5 months history of effort dyspnea and cough. Pulmonary hypertension secondary to chronic pulmonary thromboembolism was confirmed by angiography and echocardiography. The patient was operated on april 27, 1995. After the operation the patient had an enmediate and maintained normalization of his pulmonary hemodynamics. He presented periods of delirium that postponed mechanical ventilation disconnection until the 7th postoperative day, after which he had an uneventful neurological recovery. Before hospital discharge a control angiography showed complete patency of the pulmonary artery system with no evidence of residual thrombi. Presently he is enjoying a normal life and back to his teaching activities

Valvuloplastía mitral percutánea con técnica de Inoue: resultados de acuerdo al grado de alteración ecográfica / Percutaneous mitral valvuloplasty with Inoue technique: results according to the degree of echographic alterations

Hay cierta incertidumbre referente a las diferencias en resultados de acuerdo al grado de daño preexistente de la válvula mitral en pacientes sometidos a valvulotomía percutánea con el balón de Inoue. Analizamos nuestra serie consecutiva de 126 pacientes (88 por ciento mujeres) tratadas con este procedimiento desde abril de 1990 a diciembre de 1994. Todos los pacientes tuvieron un área valvular mitral (AVM, método de hemipresión por Doppler)< 1,5 cm² e insuficiencia mitral ausente o menor de grado 2/4. El mismo ecocardiografista determinó el AVM antes y 24 a 48 horas después del procedimiento. En 71 por ciento de los pacientes se efectuó una nueva medición del AVM 12 ñ 1 meses después de la valvuloplastía. La valvuloplastía falló en 5 pacientes: no se pudo cruzar la válvula mitral en 3, 1 paciente falleció durante el procedimiento y 2 tuvieron tamponamiento cardiaco tratado por cirugía de emergencia con comisurotomía quirúrgica en el mismo acto. En los 121 pacientes restantes (96 por ciento), la presión media de aurícula izquierda disminuyó de 20 ñ 6 (DS) a 11 ñ 5 mmHg (p <0,001) y el AVM aumentó de 0,96 ñ 0,16 a 1,80 ñ 0,33 cm² (p <0,001). Cuatro de los 5 casos fallidos tenían puntaje de Wilkins ò 10. En 99 pacientes con puntaje £ 7, el AVM aumentó 98 ñ 40 por ciento, en tanto que en 22 pacientes con puntaje de 8 ó 9 el AVM aumentó 79 ñ 41 por ciento (p <0,05). Tres pacientes entre los primeros y 1 entre los segundos desarrollaron insuficiencia mitral ò 3/4. Se observó una disminución leve del AVM en el control efectuado 1 año después de la valvuloplastía (1,83 ñ 0,27 a 1,73 ñ 0,29 cm²). Concluimos que la valvuloplastía mitral percutánea con el balón de Inoue es segura y efectiva en pacientes bien seleccionados (puntaje de Wilkins menor de 10). Los pacientes con puntaje > 7 tienen resultados menos favorables que aquellos con puntajes menores