[Transcatheter aortic valve implantation: experience in 17 patients]. / Implante valvular aórtico transarterial: experiencia en Chile.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is taking a leading role in the management of patients with severe aortic stenosis. Valve replacement surgery prolongs survival and is the technique of choice considering its historical background and long experience worldwide. Recently however, TAVI has positioned itself as the only standard therapy for symptomatic patients who are not candidates for surgery. AIM: To report the experience with this new technique comparing our results with those reported in the literature. MATERIAL AND METHODS: Between May 2010 and December 2011,17 patients aged 81 ± 7.3 years (58.8% men with an Euro SCORE 29 ± 22.4%) underwent a TAVI. RESULTS: The median transvalvular gradient was 54 ± 15.7 mmHg. All patients received a CoreValve™. Technical success was 100%, with a post implant gradient of 6.29 ± 3.3 mmHg. Residual aortic regurgitation was observed in 94%, none greater than grade II. There were no complications at the vascular access site. One patient developed cardiac tamponade during the procedure. Permanent pacemaker implantation was required in 35.2%. Hospital mortality rate was 5.8%, a figure that remained unchanged at 30 days of follow-up. CONCLUSIONS: In high-risk patients with aortic stenosis, TAVI has a high success rate and a low rate of complications. Besides an appropriate patient selection, a trained multidisciplinary team and technical conditions to solve possible complications of the procedure are required.

[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.

Síndrome de Austrian en endocarditis infecciosa: reporte de un caso y manejo médico quirúrgico exitoso / Austrian syndrome in infective endocarditis

Resumen: El Síndrome de Austrian, corresponde al cuadro clínico descrito por Robert Austrian en 1957, definido por la triada de Neumonía, Endocarditis Infecciosa (EI) y Meningitis, causado por Streptococcus pneumoniae. En la mayoría de los casos el vicio valvular presente, es la insuficiencia valvular aórtica, cuyo tratamiento médico y resolución quirúrgica de acuerdo con su gravedad, deben ser realizados precoz y oportunamente. Un paciente de 51 años, sin antecedentes de valvulopatía, con historia de poli consumo de alcohol y cocaína comenzó dos semanas previo a su ingreso hospitalario con síndrome febril, neumonía, y meningitis bacteriana por Streptococcus pneumoniae. Sus hemocultivos fueron negativos. El ecocardiograma transesofágico (ETE) fue compatible con EI valvular aórtica con insuficiencia moderada a severa. Se trató como EI a microorganismo desconocido y se efectuó un reemplazo valvular aórtico electivo con prótesis biológica a la 5° semana después de terminado el tratamiento médico antibiótico, cuyo resultado fue exitoso.

Abstract: A syndrome including Infective endocarditis, pneumonia and Meningitis caused by S pneumoniae was described by Robert Austrian in 1957. The aortic valve is affected in most cases. Medical followed by surgical treatment should be promptly implemented. The clinical case of a 51 year old man with a history of multiple drug consumption developing fever, pneumonia, and meningitis caused by S pneumoniae is presented. Blood cultures were negative and trans esophageal echocardiography showed aortic valve vegetations and moderate regurgitation. After multiple antibiotic treatment the patient underwent aortic valve replacement and recovered satisfactorily. Clinical and epidemiological characteristics of this syndrome are discussed.

Costo-efectividad de reemplazo valvular aórtico percutáneo vs terapia conservadora en la estenosis aórtica de muy alto riesgo en un centro terciario chileno / Cost-effectiveness of trans aortic valve replacement vs. conservative treatment in high-risk patients with severe aortic stenosis in a referral hospital center in Santiago, Chile

Introducción: El objetivo fue evaluar la costo-efectividad del reemplazo valvular aórtico percutáneo (RVAP) contra terapia conservadora (TC) en pacientes con estenosis aórtica (EA) severa de muy alto riesgo, en un centro de derivación. Métodos: Los pacientes derivados entre Enero 2013 y Septiembre 2014, considerados de muy alto riesgo y candidatos a RVAP fueron incluidos. El costo de los recursos usados, de las readmisiones y la sobrevida fueron obtenidos para determinar el tiempo de vida ganado y la relación incremental de costo-efectividad (RICE) del RVAP Resultados: El grupo estudiado quedó compuesto por 39 pacientes, con edad promedio 82±7 años, más frecuentemente mujeres (74.4%), con elevado perfil de riesgo (STS score 11.4±5.6). Diecisiete pacientes (43.6%) fueron sometidos a RVAP y 22 (56.4%) a TC. Durante el seguimiento se registraron 25 rehospitalizaciones en el grupo de TC, a un costo promedio de $4.195.073 por paciente (7,027 dólares). Todos los pacientes sometidos a RAVP recibieron con éxito una prótesis Sapien XT y fueron egresados vivos. El costo promedio estimado del RVAP fue $20.000.000 (33,500 dólares). La sobrevida media fue de 54.5% (10 eventos) en grupo TC contra 94.1% (una muerte) en el grupo RVAP [285±204 días/seguimiento] (p<0.001). Así se pudo estimar que RVAP se asoció a un incremento de vida de al menos un año, lo cual resultó en una RICE de 26,470 dólares/año de vida ganado. Conclusión: El RAVP resultó costo-efectivo comparado con la TC en pacientes portadores de EA severa de muy alto riego tratados en la realidad de un centro de derivación nacional.

Aim: to evaluate cost-effectiveness of Transcatheter Aortic Valve Replacement (TAVR) compared to conservative treatment in patients with very high risk severe aortic stenosis (AS) referred to a tertiary center in Santiago, Chile Methods: Patients with high surgical risk and severe AS referred between January 2013 and September 2014 were included. Cost of resources, readdmissions, life-years gained and incremental cost-effectiveness of TAVI were calculated Results: Thirty-nine patients were finally included. Mean age was 82±7 years old, more commonly women (74%) with a mean STS score of 11.4±5.6 that confirmed their high-risk. Seventeen patients (43.6%) had TAVR and 22 (56.4%) underwent conventional medical therapy. All patients in the TAVR group - treated with Sapien XT® device - survived the procedure and were discharged alive. Mean cost of the procedure was approximately US$ 33,500. After a mean follow-up period of 285±204 days, mean survival rate in the control group was 54.5% (10 deaths) as compared to 94.1% in the TAVR group (1 death, p<0.001). Therefore, a gain of al least one year was obtained with TAVR resulting in an incremental cost effectiveness of US$ 26.470 per year of life gained. Conclusion: TAVR resulted costly-effective compared to conventional therapy in patients with severe AS and high surgical risk in a Chilean referral center.

Implante valvular aórtico transarterial: experiencia en Chile / Transcatheter aortic valve implantation: Experience in 17 patients

Background: Transcatheter aortic valve implantation (TAVI) is taking a leading role in the management of patients with severe aortic stenosis. Valve replacement surgery prolongs survival and is the technique of choice considering its historical background and long experience worldwide. Recently however, TAVI has positioned itself as the only standard therapy for symptomatic patients who are not candidates for surgery. Aim: To report the experience with this new technique comparing our results with those reported in the literature. Material and Methods: Between May 2010 and December 2011,17patients aged 81 ± 7.3 years (58.8% men with an Euro SCORE 29 ± 22.4%) underwent a TAVI. Results: The median transvalvular gradient was 54 ± 15.7 mmHg. All patients received a CoreValveTM. Technical success was 100%, with a post implant gradient of 6.29 ± 3.3 mmHg. Residual aortic regurgita-tion was observed in 94%, none greater than grade II. There were no complications at the vascular access site. One patient developed cardiac tamponade during the procedure. Permanent pacemaker implantation was required in 35.2%. Hospital mortality rate was 5.8%, a figure that remained unchanged at 30 days offollow-up. Conclusions: In high-risk patients with aortic stenosis, TAVI has a high success rate and a low rate of complications. Besides an appropriate patient selection, a trained multidisciplinary team and technical conditions to solve possible complications of the procedure are required.

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.

[Focal atrial fibrillation. Clinical characteristic and results of radiofrequency ablation]. / Fibrilación auricular focal. Características clínicas y resultado de la ablación con radiofrecuencia.

BACKGROUND: Atrial fibrillation can originate in arrhythmogenic foci coming from the pulmonary veins. Patients with atrial fibrillation, initiated from triggering foci, can be treated with radiofrequency ablation. AIM: To report the results of radiofrequency ablation in patients with focal atrial fibrillation. PATIENTS AND METHODS: Thirteen patients with focal atrial fibrillation (8 male, aged 19 to 60 years old) are reported. Twelve had frequent crises refractory to antiarrhythmic drugs. Two had also flutter and tachycardia. One had a permanent atrial fibrillation lasting five years. Two had ventricular dysfunction and left atrial dilatation. The triggering focus was identified during the electrophysiological study, by the precocity of the potential that initiated the atrial fibrillation. RESULTS: All patients had early atrial extrasystolic beats, isolated or repetitives, that preceded atrial fibrillation. During the electrophysiological study, 18 foci (3 in the right and 15 in the left atrium all in pulmonary veins) were identified. Radiofrequency ablation had immediate success in 11 patients. In 5, a flutter was also ablated. One patient had a sinus dysfunction after the procedure and atrial fibrillation was not eliminated. In this and other patient in whom the procedure failed, a pacemaker was implanted and the atrioventricular node was blocked. In a follow up, ranging from 4 to 31 months, eight patients are asymptomatic and 3 recidivated. No complications have been detected. CONCLUSIONS: Patients with focal atrial fibrillation have common clinical and electrocardiographic features. Radiofrequency ablation of the triggering focus is possible and effective in most cases.

[Results of intraventricular resynchronization in patients with severe cardiac failure]. / Resultados clínicos de la resincronización ventricular en pacientes con insuficiencia cardíaca severa.

BACKGROUND: Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. AIM: To report the results of this therapy in patients with cardiac failure. PATIENTS AND METHODS: Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. RESULTS: In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85%), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4% (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. CONCLUSIONS: In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.

Tromboembolismo pulmonar: correlación clínico fisiopatológica y manejo terapeútico / Pulmonary thromboenbolism: clinical and physiopathological correlation and therapeutic management

El tromboembolismo pulmonar (T.E.P) constituye un cuadro clínico frecuente, de difícil diagnóstico con una mortalidad cercana al 38% en pacientes con T.E.P. sintomático. En el 80-100% de los casos, las embolias pulmonares tienen su origen en el sistema venoso profundo de extremidades inferiores. Se analizan las alteraciones hemodinámicas, humorales y respiratorias que se producen en el T.E.P. y las manifestaciones clínicas consiguientes. Entre los exámenes de laboratorio, se destaca la importancia de la cintigrafía pulmonar y de la angiografía selectiva para el diagnóstico de esta afección. Con el empleo oportuno de heparina, trombolíticos y anticoagulantes orales, la mortalidad en esta enfermedad puede disminuirse sustancialmente. La deambulación precoz y la heparina prescrita en la forma de minidosis, son medidas efectivas de prevención