Limb ischemia in patients with COVID-19 / Isquemia de membros em pacientes com COVID-19

Abstract This narrative review covers the life-threatening thromboembolic events associated with SARS-CoV-2 infection/COVID-19. It addresses the physical changes that cause vascular and arterial damage to limbs, laboratory management of coagulation, and management of anticoagulation. COVID-19's relationship with deep venous thrombosis and arterial thrombosis is also emphasized. The main thromboembolic events described in the literature are illustrated with examples from our experience with COVID-19 patients.

Resumo Esta revisão narrativa abrange os eventos tromboembólicos com risco de vida associados a infecção por SARS-CoV-2/COVID-19. Aborda as mudanças físicas que causam danos vasculares e arteriais aos membros, o manejo laboratorial da coagulação e o manejo da anticoagulação. A relação de COVID-19 com trombose venosa profunda e trombose arterial também é enfatizada. Os principais eventos tromboembólicos descritos na literatura são ilustrados a partir de nossa experiência com pacientes COVID-19.

Anticoagulation in patients with cardiac manifestations of Chagas disease and cardioembolic ischemic stroke / Anticoagulação nas manifestações cardíacas da doença de Chagas e acidente vascular cerebral isquêmico cardioembólico

ABSTRACT Objectives To describe anticoagulation characteristics in patients with cardiac complications from Chagas disease and compare participants with and without cardioembolic ischemic stroke (CIS). Methods A retrospective cohort of patients with Chagas disease, using anticoagulation, conducted from January 2011 to December 2014. Results Forty-two patients with Chagas disease who were using anticoagulation were studied (age 62.9±12.4 years), 59.5% female and 47.6% with previous CIS, 78.6% with non-valvular atrial fibrillation and 69.7% with dilated cardiomyopathy. Warfarin was used in 78.6% of patients and dabigatran (at different times) in 38%. In the warfarin group, those with CIS had more medical appointments per person-years of follow-up (11.7 vs 7.9), a higher proportion of international normalized ratios within the therapeutic range (57% vs 42% medical appointments, p = 0.025) and an eight times higher frequency of minor bleeding (0.64 vs 0.07 medical appointments). Conclusion Patients with Chagas disease and previous CIS had better control of INR with a higher frequency of minor bleeding.

RESUMO Objetivos descrever as características da anticoagulação em pacientes com manifestações cardíacas da doença de Chagas (MCDC) e comparar os participantes com sem acidente vascular cerebral isquêmico cardioembólico (AVCIC). Resultados 42 pacientes com MCDC em anticoagulação foram estudados (62,9 ± 12,4 anos), 59,5% do sexo feminino e 47,6% com AVCIC prévio, 78,6% portadores de fibrilação atrial não valvar e 69,7% com cardiomiopatia dilatada. Varfarina foi utilizada em 78,6% dos pacientes e dabigatrana em 38% (em momentos diferentes). No grupo da varfarina, aqueles com AVCIC tiveram mais consultas médicas por pessoas-ano de seguimento (11,7 vs 7,9), maior taxa de RNI na faixa terapêutica (57% vs 42% consultas médicas, p = 0,025) e uma frequência oito vezes maior de sangramento menor (0,64 vs. 0,07 consultas médicas). Conclusão pacientes com MCDC e AVCIC prévio têm melhor controle de RNI com maior frequência de sangramento menor.

Orejuela izquierda en la enfermedad reumática mitral: principal fuente embolígena en la fibrilación auricular / Left atrial appendage in rheumatic mitral valve disease: The main source of embolism in atrial fibrillation

Resumen: Objetivo: Demostrar que la resección quirúrgica de la orejuela izquierda en los pacientes con enfermedad reumática mitral y fibrilación auricular persistente de larga evolución disminuye la posibilidad de embolia cerebral. Asimismo, esto también elimina la necesidad de anticoagulación oral a largo plazo. Método: Se estudiaron en forma observacional y prospectiva 27 pacientes adultos con enfermedad reumática mitral y fibrilación auricular persistente de larga evolución, sometidos a cirugía valvular mitral y resección quirúrgica de la orejuela izquierda. La anticoagulación oral con warfarina fue suspendida después del tercer mes postoperatorio, recibiendo solamente aspirina a largo plazo. El punto final fue la ausencia de embolia cerebral. Secundariamente, se evaluó la formación de trombos en la aurícula izquierda por ecocardiografía transtorácica postoperatoria. Resultados: Después del tercer mes, ningún paciente presentó embolia cerebral. Un paciente exhibió isquemia cerebral transitoria dentro de los primeros 3 meses en tratamiento con warfarina. Secundariamente, en la cirugía se encontró trombo en aurícula izquierda en 11 casos (40.7%). De estos 11, 6 (54.5%) habían tenido embolia cerebral previamente, sin encontrar significación estadística (p = 0.703). Conclusiones: Este estudio muestra que pudiera haber indicios de que la orejuela izquierda pueda ser la principal fuente embolígena en la enfermedad reumática mitral, y que su resección pueda eliminar el riesgo de embolia cerebral en pacientes con enfermedad reumática mitral y fibrilación auricular persistente de larga evolución.

Abstract: Objective: To demonstrate that surgical removal of the left atrial appendage in patients with rheumatic mitral valve disease and long standing persistent atrial fibrillation decreases the possibility of stroke. This also removes the need for long-term oral anticoagulation after surgery. Method: A descriptive, prospective, observational study was conducted on 27 adult patients with rheumatic mitral valve disease and long standing persistent atrial fibrillation, who had undergone mitral valve surgery and surgical removal of the left atrial appendage. Oral anti-coagulation was stopped in the third month after surgery. The end-point was the absence of embolic stroke. An assessment was also made of postoperative embolism formation in the left atrium using transthoracic echocardiography. Results: None of the patients showed embolic stroke after the third post-operative month. Only one patient exhibited transient ischaemic attack on warfarin therapy within the three postoperative months. Left atrial thrombi were also found in 11 (40.7%) cases during surgery. Of these, 6 (54.5%) had had embolic stroke, with no statistical significance (P = .703). Conclusions: This study suggests there might be signs that the left atrial appendage may be the main source of emboli in rheumatic mitral valve disease, and its resection could eliminate the risk of stroke in patients with rheumatic mitral valve disease and long-standing persistent atrial fibrillation.

Factores de riesgo para la formación de trombos sobre el dispositivo ULTRASEPT®, en pacientes con fibrilación auricular sometidos a cierre percutáneo de orejuela izquierda / Risk factors for thrombus formation on the ULTRASEPT® device in patiens with atrial fibrillation being submitted to left atrial appendage closure

Introducción: El cierre percutáneo de orejuela izquierda con dispositivos percutáneos (CPOI) ha demostrado ser útil en la prevención de embolia arterial como alternativa al tratamiento anticoagulante (TACO) en pacientes con fibrilación auricular no valvular (FANV). Sin embargo, en las primeras semanas post implante, existe el riesgo de formación de trombos sobre el dispositivo. Objetivos: Describir e Identificar los factores de riesgo para la formación de trombos sobre el dispositivo posterior al cierre de orejuela izquierda. Métodos: Se incluyeron 15 pacientes con FANV y alto riesgo hemorrágico, sometidos a CPOI con dispositivo Ultrasept (Cardia Inc., Eagan, MN), en el Hospital Clínico de la Universidad Católica, entre Abril 2013 y Junio 2014. A todos se les realizó eco-cardiograma transesofágico (ETE) al primer, tercer y sexto mes post implante. Todos los pacientes recibieron aspirina en forma permanente y TACO por 45 días el que se reemplazó por clopidogrel hasta el sexto mes post implante. Se analizaron parámetros clínicos y ecocardiográficos en forma retrospectiva para identificar los factores de riesgo asociados a la formación de trombos sobre el dispositivo. Resultados: La edad promedio de los pacientes fue 77± 8 años, 73% de sexo masculino. El 80% tenía FA permanente y 20% FA paroxística. EL Score de CHA2DS2VASc promedio fue de 5 (mínimo 3, máximo 8 puntos). En 4 pacientes (26.6%), encontramos trombos en el dispositivo en el seguimiento con ETE (1 paciente al primer mes y 3 al tercer mes), sin consecuencias clínicas. Al comparar los pacientes que formaron trombos con el resto, no hubo diferencias en las variables clínicas (edad, sexo, Hipertensión arterial (HTA), Diabetes Mellitus (DM), Dislipidemia, Tabaquismo, Insuficiencia Renal, AVE previos), ni en las variables ecocardiográficas estudiadas, como el área de la aurícula izquierda (AI), contraste espontáneo en la AI, insuficiencia mitral ni cierre incompleto de orejuela (medida por la existencia de flujo peridispositivo). Sin embargo, los pacientes con trombos presentaron CHA2DS2VASc score más alto (7.1 vs 4.7; p= 0.001) y fracción de eyección (FE) más baja (43% vs 55%; p= 0.001). En la curva ROC de CHA2DS2VASc para predecir una mayor probabilidad de formación de trombos, un valor > 6 obtiene una sensibilidad de un 100% y una especificidad de un 80%. En nuestro seguimiento clínico de 2 años ± 5.7 meses posterior al implante, 1 paciente tuvo un AVE isquémico identificando como fuente enfermedad carotidea (no tenía trombos en el dispositivo). El resto de los pacientes se mantienen asintomáticos. Conclusiones: En nuestra experiencia, el CHA2DS-2VASc score (> 6) y la fracción de eyección baja, fueron factores de riesgo para la formación de trombos sobre el dispositivo de cierre de orejuela. Este hallazgo debería confirmarse en series más grandes dado que podría cambiar la estrategia de anticoagulación post implante.

Background: Percutaneous closure of the left atrial appendage (LAA) has been shown to be useful in the prevention of arterial embolism as an alternative to oral anticoagulants in patients with non valvular atrial fibrillation. However, thrombus formation may develop in the first weeks following device implantation/ Aim: to identify risk factors for thrombus development on devices used for LAA closure. Methods: 15 patients with non valvular AF and high risk for anticoagulant treatment were included. Patients received an Ultrasept (Cardia Inc., Eagan, MN) between April 2013 and June 2014. Transesophageal echocardiography was performed in all patients 1, 3 and 6 months post implant. All patients received aspirin permanently and acenocumarol for 45 days, followed by clopidogrel until 6 months post implant. Results: Mean age was 77 years old (SD 8). 73% were males. AF was permanent in 80% and paroxysmal in 20%. Mean CHA2DS2VASC was 8 (range 3 to 8). Thrombus were revealed by TEE in 4 patients (26.6%), at 1 month (1 patient) and at 3 months post implant (3 patients). No complications occurred in these patients. Clinical variables (age, sex, hyper-tension, diabetes, dyslipidemia, smoking habit, renal failure and prior strokes) were no different in patients with or without thrombus. The same was true for left atrial size, mitral insufficiency or incomplete closure of LAA. In contrast, patients with thrombus formation had a higher CHA2DS2VASc score (7.1 vs 4.7, p=0.001 and a lower LV ejection fraction (43% vs 55%, p=0.001). A CHA2DS2VASc score > 6 was 100% sensible and 80% specific for thrombus formation (ROC curve). After a follow-up of 24 ± 5 months only 1 patients had and ischemic cerebro-vascular event which was attributed to carotid artery disease (the patient had no evidence of device thrombus). All other patients remain asymptomatic. Conclusion: A CHA2DS2VASc score > 6 and a low ejection fraction were risk factors for thrombus formation on LAA closing device. Confirmation of these findings in a larger series of patients could lead to a change in anticoagulant strategy following the implantation of devices to close the LAA.

Profilaxia do tromboembolismo venoso em cirurgia ortopédica / Prophylaxis of venous thromboembolism in orthopaedic surgery

A importância da profilaxia do tromboembolismo venoso e de suas complicações em cirurgia ortopédica é cada vez mais significativa. Esta revisão aborda as bases fisiopatológicas da formação dos trombos em geral e em cirurgia ortopédica, sua incidência, fatores predisponentes e complicações. Apresenta, ainda, uma abordagem atualizada e crítica dos meios de profilaxia atualmente disponíveis em nosso meio.

The relevance of prophylaxis of venous thromboembolism and its complications in orthopedic surgery is increasingly significant. This review discusses the pathophysiology of thrombus formation in general and orthopedic surgery, its incidence, predisposing factors and complications. It also presents an updated presen tation and critique of prophylaxis currently available in our environment.

Estudo comparativo entre protocolos para profilaxia da trombose venosa profunda: uma nova proposta / Deep venous thrombosis prophylaxis protocols comparative study: a new proposal

Introdução: O artigo compara os protocolos Davison-Caprini (americano) e Sandri(brasileiro) para profilaxia da trombose venosa profunda (TVP), buscando a elaboração de um novo protocolo, mais abrangente e aplicável. Método: Foi realizado um estudo prospectivo, durante um ano, abrangendo 212 pacientes, comparando os protocolos quanto à estratificação de risco de TVP, e ao tipo de profilaxia indicado. Um novo protocolo foi proposto, aplicado e comparado aos anteriores. Resultados: Obteve-se um novo protocolo, denominado Sandri modificado, que restringe a heparina a um grupo seleto de pacientes, semelhante ao americano, mantendo-se adequado tanto para cirurgias estéticas quanto reparadoras. Conclusões: A baixa adesão, por parte dos cirurgiões plásticos, ao uso rotineiro da profilaxia de TVP, espelha a escassez de informação sobre o tema. O protocolo Sandri modificado busca melhorar a compreensão e a aplicabilidade da profilaxiada TVP na cirurgia plástica.

Background: Compare Davison-Caprini (American) and Sandri (Brazilian) protocols for deep vein thrombosis (DVT) prophylaxis, suggesting a new protocol, more comprehensive and applicable. Method: A prospective study was conducted over a year, including 212 patients, comparing the protocols on DVT stratification risk, and the type of prophylaxis indicated. A new protocol was proposed, applied and compared to the previous. Results: The new protocol, modified Sandri, restricts the heparin to a select group of patients, similar to the American protocol, and remains suitable for both aesthetic and reconstructive surgery. Conclusions: The low adhesion of plastic surgeons to the routine use of DVT prophylaxis reflects lack of information concerning this topic. The Sandri modified protocol seeks improvement on the understanding and applicability of DVT prophylaxis in plastic surgery.

Experiencia preliminar: STENT MGUARD en angioplastía coronaria con alta carga trombótica, ¿una nueva alternativa en protección embólica? / Percutaneous coronary angioplasty in patients with high thrombotic load: a preliminary evaluation using the MGuard stent

Introducción: La microembolización se asocia a más eventos cardiovasculares adversos (MACE) especialmente en angioplastía (PTCA) de puentes venosos aortocoronarios (PAC) o en síndrome coronario agudo (SCA). El stent MGuard evitaría la embolización distal. Nuestro objetivo: evaluar el stent con micromalla de dacron como alternativa de protección embólica. Métodos: Registro prospectivo de PTCA con stent MGuard en de SCA de PAC y vasos nativos. Resultados: 15 angioplastias, de ellas 53 por ciento con infarto agudo miocárdico con supradesnivel de ST (IAM con SDST). PTCA en vasos nativos: 60 por ciento y PAC: 40 por ciento (antigüedad: 13 +/- 3 años). El 53 por ciento tuvo flujo inicial TIMI 0-1, alto contenido trombótico (66 por ciento: 4-5 en escala de trombos TIMI). Se predilató la lesión en 73 por ciento de los casos, se empleó Reopro en 2 casos, no se usó filtros de protección ni aspirador de trombos. Las dimensiones del stent MGuard: 22.2 +/- 4.4 mm de largo por 3.7 +/- 0.44 mm de diámetro. El 100 por ciento con flujo TIMI 3 final, 93 por ciento con impregnación miocárdica grado 3. Subgrupo de IAM con SDST: 71 por ciento obtuvo < 23 cuadros TIMI/segundo, 100 por ciento con regresión del SDST mayor de 50 por ciento a 90 minutos de PTCA. Subgrupo de PTCA de PAC: (excepto caso de PTCA de PAC en IAM c/SDST) no se registró elevación de la CK total o MB post PTCA. Seguimiento: un caso de trombosis al mes. Conclusión: El MGuard stent parece ser efectivo en la protección de la microcirculación. Se requieren estudios para evaluar la seguridad clínica y eficacia en protección embólica.

Background: Coronary angioplasty (PTCA) is associated to a greater incidence of major adverse cardiac events (MACE) in patients with stenosis of saphenous vein grafts (SVG) and in those with acute coronary syndromes (ACS). The MGuard stent, a device with a dacron micro mesh, is currently being evaluated for the prevention of distal thrombotic embolization in these patients. Aim to evaluate the MGuard stent, for the prevention of distal embolization. Methods: analysis of a prospective registry of patients submitted to PTCA for ACS in native coronary arteries or occluded SVG using the MGuard stent. Results: 15 PTCA procedures were performed, 53 percent in patients with ST segment elevation acute myocardial infarction (STE-MI). PTCA was performed in native vessels in 60 percent patients and in SVG in 40 percent. Interval from surgery in these patients was 13+/-3 years. 53 percent of patients had initial TIMI fow rate 0-1 and 66 percent had a thrombotic load of 4-5 (TIMI scale). Lesions were predilated in 73 percent of cases; abxicimab was used in 2 patients and no protection filters or thrombus aspiration were performed. MGuard stent dimensions were 22.2+/-4.4 mm in length, and 3.7+/-0.44 mm in diameter. Final TIMI 3 fow was observed in all patients; 93 percent of then had grade 3 myocardial impregnation. In the subgroup of patients with STE-MI, a 23 frames/sec TIMI frame count was observed with >50 percent reduction of ST elevation 90 min after PTCA. In patients with SVG, except one patient with ACS, no elevation of total or MB- CK was observed. Follow up revealed reocclusion in 1 patient, 1 month after the procedure. Conclusion: The MGuard stent appears to be an effective device to protect the microcirculation form distal embolization during PTCA. Studies with larger number of patients and extended periods of follow up are encouraged by these results.

Avaliação da captura de fragmentos por meio da filtração intra-aórtica em pacientes submetidos à troca valvar aórtica / Particulate emboli capture by an intra-aortic filter device during aortic valve replacement

OBJETIVO: O objetivo deste estudo foi avaliar a atividade embólica de pacientes portadores de estenose aórtica calcificada submetidos a troca valvar aórtica por meio da filtração intra-aórtica com dispositivo EMBOL-X® System (Edwards Lifesciences Inc., Mountain View, CA, USA). MÉTODOS: De janeiro de 2007 a julho de 2007, foi utilizado o filtro intra-aórtico EMBOL-X após o despinçamento aórtico em 13 portadores de estenose aórtica calcificada submetidos a troca valvar aórtica consecutivamente. A média de idade dos pacientes foi 63,7 anos (34-79) e 61,5% eram do sexo feminino. A média do tempo de CEC foi 60,2±7,5 (45-72) minutos e a média do tempo despinçamento aórtico foi 50±7,5 (35-63) minutos. Após a retirada dos filtros, eles foram fixados em formalina, analisados macroscopicamente e quantificados os fragmentos capturados. Foi realizado exame histológico do material capturado. RESULTADOS Não foi observado nenhum caso de complicação neurológica. Nenhum paciente apresentou insuficiência renal pós-operatória. Não houve óbitos hospitalares. Partículas embólicas foram encontradas em cinco (38,5%) dos filtros. Das partículas embólicas capturadas, em dois (40%) filtros havia fibrina, dois (40%) apresentavam tecido conjuntivo, um (20%) continha hemácias e em um não foi possível determinar a natureza. CONCLUSÃO: O dispositivo EMBOL-X® System foi efetivo na captação de fragmentos intra-aórticos na substituição da valva aórtica em pacientes com estenose aórtica calcificada.

OBJECTIVE: This study aims to analyze the embolic activity in patients with calcified aortic stenosis who underwent aortic valve replacement using intra-aortic filtration with an EMBOL-X® System device (Edwards Lifesciences Inc., Mountain View, CA, USA). METHODS: From January 2007 to July 2007, 13 consecutive patients with calcified aortic stenosis, who underwent isolated aortic valve replacement using intra-aortic filtration by an EMBOL-X® System for 5 minutes after aortic clamp release, were evaluated. Mean patient age was 63.7 years (range 34 to 79 years) and 61.5% were female. The mean bypass time was 60.2 ± 7.5 minutes (range 45 to 72 minutes) and the mean cross-clamp time was 50 ± 7.5 minutes (range 35 to 63 minutes). Following removal, each filter was fixed in formalin and analyzed macroscopically with the captured fragments being counted. Histological examinations of the captured material were performed. RESULTS: There were no strokes or gross neurological events. There were no cases of postoperative renal failure. No deaths were reported during hospitalization. Particulate emboli were found in five (38.5%) of the filters. On histological analysis of the particulate emboli captured, two (40%) contained fibrin, two (40%) presented conjunctive tissue, one (20%) contained red blood cells and in one it was not possible to determine the nature of the particulates captured. CONCLUSION: The EMBOL-X® System device was effective in particulate emboli capture in aortic valve replacement surgery of patients with calcified aortic stenosis.

Utilidad de la aspiración de trombos de la arteria culpable en infarto agudo del miocardio / Usefulness of thrombus aspiration when treating the culprit artery in patients with acute myocardial infarction

Introducción: La angioplastía primaria es el método más efectivo de reperfusión en el infarto agudo al miocardio (IAM). Sin embargo, no en todos los pacientes en los que se logra restaurar el flujo epicárdico se consigue una rerperfusión eficaz, lo cual puede deberse a migración de trombos durante el procedimiento. Objetivo: Evaluar el efecto de la aspiración de trombos en el IAM, mediante uso de catéter ad hoc, sin oclusión distal. Método: Se incluyeron 33 pacientes con IAM sometidos a angioplastía primaria desde diciembre del 2004 a octubre de 2005, 19 en el grupo de aspiración de trombos y 14 en el grupo control. La arteria culpable debía ser >2,5 mm. Ningunotenía falla ventricular izquierda. La aspiración de trombos se hizo mediante catéter Export, compatible con catéter guía 6 French. A todos los pacientes se les implantó stent. La reperfusión precoz se evaluó por disminución mayor al 50 por ciento del supradesnivel del ST (SDST) a los 60 minutos de la última inyección y el remodelamiento miocárdico por el aumento mayor al 20 por ciento de los volúmenes ventriculares izquierdos a los 6 meses post infarto medidos por ecocardiograma. El análisis estadistico incluyó chi cuadrado y T de student para muestras no pareadas. Resultados: La edad promedio fue 64 ± 9 años, 23 hombres (69 por ciento). No hubo diferencias significativas entre los grupos en edad, hipertensión, dislipidemia, diabetes, función ventricular y tiempo de evolución del infarto. Los pacientes del grupo aspiración eran mayoritariamente hombres (81 versus 33 por ciento, p< 0.05)). La arteria culpable fue con mayor frecuencia la descendente anterior (56 y 50 por ciento, p=NS) y el diámetro de referencia del vaso de 3,2 y 3,4 mm (p=NS) en aspiración y control, respectivamente. La disminución precoz del SDST fue de 69 y 83 por ciento (p=0,4) y el remodelamiento a los 6 meses de 13 y 17 por ciento (p=0,2) en aspiración y control respectivamente. Al analizar sólo los pacientes con trombos angiográfi...

Impacto clínico da ecocardiografia transesofágica em pacientes com acidente vascular cerebral sem evidência clínica de fonte emboligênica cardíaca / Clinical impact of transesophageal echocardiography in patients with stroke without clinical evidence of cardiovascular sources of emboli

OBJECTIVE: The purpose of this study is to evaluate the impact of transeophageal echocardiography on management of patients at low-risk for cardiogenic embolism to prevent new potential cardiovascular sources of emboli. METHODS: We studied 69 patients with ischemic stroke at low-risk for cardiogenic embolism. Transeophageal echocardiography was performed to access: left atrium enlargement; communication or aneurysm of the interatrial septum; patent foramen ovale; spontaneous echo contrast or intracavitary thrombi; the presence of intraaortic atherosclerotic plaques or thrombi; significant valvar morphologic alteration or dysfunction; left ventricle enlargement, hypertrophy, or contractile abnormality. Transesophageal echocardiography altered clinical management, and we adopted anticoagulant therapy or another procedure apart from the use of acetylsalicylic acid. RESULTS: Transeophageal echocardiography detected at least one abnormality in 40 cases (58 percent). Clinical conduct was adjusted after the performance of transesophageal echocardiography in 11 patients (15.9 percent); anticoagulation was added in 10 cases and surgical correction in one patient. CONCLUSION: Transeophageal echocardiography was a very useful tool in the secondary prevention for stroke in patients at low risk for cardiogenic embolism

Tratamiento de la fibrilación auricular: un dilema permanente / Treatment of atrial fibrillation: a persistent dilema

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. Increased life expectancy will result in a higher prevalence of AF. Treatment of AF constitutes a persistent medical dilemma. Different multicenter trials have confirmed that oral anticoagulant therapy is the best choice for the prevention of systemic embolism. It must be recognized, however, that the incidence of systemic embolism in patients with AF varies according to the presence and type of underlying heart disease. Advanced age increases the risk of emboli in patients with AF. At the same time, older patients have a higher risk of hemorrhage when treated with oral anticoagulants. Thus, careful titrated individual oral anticoagulant therapy targeted to a safe and effective INR must be considered in patients with AF. Another dilemma in AF patients is the convenience of restoring sinus rhythm and indicating permanent antiarrhythmic therapy versus the alternative of heart rate control plus oral anticoagulants. Several multicenter trials now in progress have addressed this issue and most likely will answer these questions. Identification of patients with paroxysmal AF and risk of systemic embolism constitutes another dilemma, since only a small proportion of these patients evolve to chronic arrhythmia. Advanced age, history of hypertension and left atrial enlargement in 2D Echo are well recognized risk factors for embolism in patients with non valvular paroxysmal AF. A history of previous embolism constitutes another risk factor and supports the hypothesis that AF may activate systemic coagulation factors and left atrial thrombus formation in some patients

Análisis ultrasonográfico del sistema venoso profundo de las extremidades inferiores en el diagnóstico de trombosis / Ultrasound evaluation of deep vein thrombosis of the lower extremities

La compresión por ultrasonido es un método no invasivo para el diagnóstico de trombosis venosa profunda (TVP) en las extremidades. Las principales indicaciones del estudio son confirmar la sospecha clínica de TVP y localizar la fuente de émbolos en pacientes con tromboembolia pulmonar. El uso de las tecnologías Doppler y Doppler color facilitar la realización y acorta el tiempo de estudio, pero no mejora la sensibilidad ni la especificidad del método de compresión para el diagnóstico de TVP. La información se debe interpretar con conocimiento de los datos clínicos y es muy importante que exista comunicación estrecha entre el radiólogo y el clínico para que los resultados del estudio sean de utilidad en el manejo del paciente

Seguimento de 8 anos de prótese aórtica Medtronic-hall: influência da anticoagulaçäo oral na ocorrência de embolias / Follow-up of 8 years of the Medtronic-hall aortic prosthesis: influence of oral anti-coagulation on embolism incidence

Foram estudados 165 sobreviventes à prótese aórtica Medtronic-Hall, operados entre setembro de 1979 e setembro de 1987. As idades variaram entre 14 e 68 anos (m = 35,2); 129 eram masculinos, 36 femininos. As lesöes operadas foram 70 insuficiências, 37 estenoses e 39 duplas lesöes aórticas. Havia 8 disfunçöes de próteses, 8 endocardites agudas e 3 comunicaçöes interventriculares + insuficiência aórtica. O seguimento foi de 163 (98,7%) pacientes, sendo 9 perdidos durante o período de observaçäo. Houve 45 óbitos tardios, sendo de 59% EP 10,9% a probabilidade atuarial de sobrevida aos 8 anos. Houve 26 episódios embólicso em 21 pacientes, sendo de 69,8% EP 11,7% a probabilidade de näo ocorrência de embolia e de 39,7% EP 10,4% de sobrevida sem embolia. A incidência global de episódios foi de 3,5 por pacientes/ano, sendo 6 fatais (23%). Quanto ao uso de anticoagulaçäo ora, os pacientes dividiram-se em 3 grupos. No grupo A houve 144 pacientes, com uma incidência linearizada de 3,2 por 100 pacientes/ano. No grupo B - 21 pacientes que passaram a tomar anticoagulantes em seguida á operaçäo, houve 1,9 episódios por 100 pacientes/ano. No grupo C - 9 pacientes que iniciaram a anticoagulaçäo após a ocorrência de um episódio embólico, apresentaram 8,1 embolias por 100 pacientes/ano. Concluímos que näo foi possível demonstrar a eficiência da anticoagulaçäo oral, nas condiçöes em que foi conduzida, na presente série, na prevençäo das embolias. Após a ocorrência de um episódio embólico, sua instituiçäo näo foi suficiente para diminuir, significativamente, a recorrência desta complicaçäo