Alejandro Fernández

Midterm Results of a Sirolimus-Eluting Stent Implanted for Recurrent Carotid In-Stent Restenosis

One of the concerns about carotid artery stenting (CAS) is the development of restenosis. Although the incidence of restenosis is low (3% to 8% in large series) due to the large reference vessel diameter, the number of cases will continue to rise as more CAS procedures are performed each year. While drug-eluting stent implantation has replaced balloon angioplasty and brachytherapy for the treatment of in-stent restenosis in the coronary arteries, there is scarce information regarding their use for carotid in-stent restenosis. In 2007, Iancu and Lazar reported sustained patency of a drug-eluting stent 1 year after treatment for carotid in-stent restenosis. We have recently documented 30-month follow-up in a patient we treated for recurrent in-stent restenosis with a drugeluting stent. The 53-year-old diabetic woman with multiple comorbidities was seen for symptoms of bilateral carotid artery disease. Her left internal carotid artery (ICA) was chronically occluded, and the right ICA had an 80% stenosis (Figure, A); the intracranial circulation was free of hemodynamically significant lesions. An 8340-mm Wallstent under FilterWire EZ embolic protection (Boston Scientific, Natick, MA, USA) was implanted in the right ICA with excellent results (Figure, B). The patient was discharged on aspirin and clopidogrel, but 1 year later, she was seen for dizziness and left arm paresthesia. A high-grade in-stent restenosis was treated with balloon dilation without complications. Nine months later, the patient was admitted for unstable angina and left arm paresthesia. Ultrasound suggested a highgrade recurrent in-stent restenosis (Figure, C). Surgery was proposed but dismissed by the vascular surgeon due to the high cervical location of the stenosis and contralateral carotid occlusion, so we implanted a 3.5-333mm Cypher coronary stent (Cordis, Miami, FL, USA) under cerebral protection (Figure, D,E); the stent was further expanded with a 4.5-mm balloon. The patient was discharged on longterm aspirin and clopidogrel therapy. Thirty months later, she was admitted for left leg critical ischemia, but she was free of any neurological deficit or symptom. Carotid angiography showed no evidence of restenosis (Figure, F) in the right ICA stent.

Effects of overexpansion on stents' recoil, symmetry/asymmetry, and neointimal hyperplasia in aortas of hypercholesterolemic rabbits

BACKGROUND It is not known whether overexpansion modifies stent recoil, symmetric distribution of struts, and neointimal hyperplasia. OBJECTIVES The objectives were (a) to evaluate whether stent overexpansion modifies the geometric configuration of the stent in the arterial wall, (b) to determine the relationship between overexpansion and stent recoil, and (c) to evaluate the relationship between the distribution of struts and neointimal hyperplasia. METHODS Twenty tubular stainless steel 316L stents (3.0 and 3.5 mm in diameter) were implanted at 20 and 10 atm, respectively, in the abdominal aorta of New Zealand rabbits fed a hypercholesterolemic diet (1% cholesterol). Sham operations were also performed in seven animals. Eight weeks after implantation or sham operation, an intravascular ultrasound (IVUS) study was performed to measure stent recoil and aid in stent classification (symmetric or asymmetric) according to strut distribution. The degree of injury and neointimal hyperplasia were also evaluated in hematoxylin-eosin stained sections. RESULTS The symmetry/asymmetry of stents assessed by IVUS, as well as the neointimal hyperplasia, was similar in both groups. Stent recoil was significantly greater in the 3.0-mm stent (overexpanded) group (0.28+/-0.02 mm), as compared with stent recoil in the 3.5-mm stent group (0.10+/-0.01 mm, P<.05). The neointimal hyperplasia in histological slices, independent of the implant technique, was predominantly in zones with higher strut concentration as compared with zones with fewer struts. CONCLUSIONS Stent overexpansion enhanced stent recoil and did not modify symmetric and asymmetric strut distribution. Neointimal hyperplasia was not modified by the implant technique. Interestingly, significant hyperplasia was observed in locations with greater strut concentration, independent of overexpansion.

A repetição da valvuloplastia aórtica por balão é uma boa estratégia para alívio dos sintomas e seleção de pacientes para substituição percutânea da valva aórtica

INTRODUCAO: A valvuloplastia aortica por balao voltou a ganhar interesse desde o inicio da era da substituicao percutânea da valva aortica, por ser um procedimento que pode ser repetido como ponte e tambem por ser boa estrategia para a selecao de pacientes para o novo procedimento. METODO: De janeiro de 2001 a janeiro de 2009, 174 pacientes consecutivos com estenose aortica sintomatica grave e alto risco cirurgico calculado pelo EuroSCORE/ STS foram submetidos a valvuloplastia aortica por balao na Franca e na Argentina, utilizando-se a mesma tecnica. Desse total, 21 (12,1%) precisaram repetir a valvuloplastia aortica por balao em decorrencia de reestenose e os resultados foram comparados aos dos 153 pacientes que realizaram somente o primeiro procedimento. A tecnica mais utilizada foi o acesso retrogrado com abordagem femoral utilizando introdutores de 10 F, 12 F ou 14 F, com tamanhos de balao variando de 20 mm a 23 mm. RESULTADOS: A media de idade foi de 80,4 ± 9,7 anos e o EuroSCORE foi de 21 ± 2%. Abordagem femoral retrograda foi utilizada em 95% dos casos. Os resultados do procedimento primario foram os seguintes: a area valvar aortica aumentou de 0,9 ± 19 cm2 para 1,02 ± 0,20 cm2 e o gradiente medio caiu de 50 ± 21 mmHg para 22 ± 11 mmHg. Os resultados foram semelhantes apos a repeticao da valvuloplastia aortica por balao em termos da area valvar aortica, com melhora de 0,60 ± 0,1 cm2 para 1,01 ± 0,25 cm2 em um periodo de 13 ± 9 meses entre os dois procedimentos. As taxas de complicacoes hospitalares foram: morte, 3,3% vs. 9,5% (P = 0,20); acidente vascular cerebral embolico, 1,3% vs. 0 (P = 0,20); regurgitacao aortica macica, 3,3% vs. 9,5% (P = 0,20); ruptura do balao, 1,3% vs. 0 (P = 0,20); tamponamento pericardico, 0 vs. 5% (P = 0,12); e complicacoes vasculares, 3,9% vs. 9,5% (P = 0,25). No total, 48 pacientes (27,5%) foram selecionados como bons candidatos para substituicao percutânea da valva aortica durante o periodo de acompanhamento nos dois paises, dos quais 36 realizaram o procedimento na Franca e 4, na Argentina. CONCLUSOES: A repeticao da valvuloplastia aortica por balao e uma estrategia util em pacientes idosos naocirurgicos com estenose aortica sintomatica grave para aliviar os sintomas apos reestenose e como ponte para a substituicao percutânea da valva aortica. Essa tecnica pode ser repetida com baixa taxa de complicacoes.

Consenso CACI: Medición de la fracción de reserva de flujo coronario

La angiografía coronaria permite visualizar la luz arterial e inferir la presencia de lesiones obstructivas a través de la disminución localizada o difusa de la luz. Sin embargo, especialmente en obstrucciones intermedias, el significado funcional de una estenosis está relacionado no solo al grado de estrechamiento de la luz sino a la longitud de ese estrechamiento, a la cantidad de miocardio dependiente del vaso comprometido y a la circulación colateral, en caso de que estuviera presente1,2. Lo expuesto precedentemente más la gran variabilidad interobservador y el hecho de que los sistemas computarizados de angiografía cuantitativa solo tienen valor marginal para definir el grado de significancia de una lesión hacen de la coronariografía un método impreciso para identificar qué lesiones producen isquemia miocárdica cuando el compromiso de la luz es intermedio (40 a 70% del diámetro). Las pruebas funcionales tienen una especificidad limitada y no permiten identificar lesión responsable cuando más de una placa obstruye la luz en grado intermedio en el mismo territorio. En este contexto y considerando la elevada prevalencia de ateromatosis coronaria, especialmente de lesiones intermedias, la falta de un diagnóstico funcional más preciso puede derivar en una cantidad de revascularizaciones innecesarias. La medición de la Fracción de Reserva de Flujo Coronario, conocida como FFR por su acrónimo en inglés, permite determinar el grado de significación funcional de las lesiones obstructivas coronarias y definir con mayor precisión la necesidad de tratamiento de las mismas.

como interpretar una coronagrafía

Como interpretar una coronarioagrafia. Indicaciones, utilidad en patologia cardiovascular. Se aprecia en el video la realizacion del estudio. LINK https://www.youtube.com/watch?v=Y1iSwc_zRJc&feature=em-upload_owner