Volume Plaquetário Médio está Associado com Reperfusão Inadequada Detectada por Angiografia em Pacientes com Terapia Fibrinolítica Bem Sucedida / Mean Platelet Volume is Associated with Inadequate Reperfusion Detected by Angiography in Patients with Successful Fibrinolytic Therapy

Fundamento: Volume plaquetário médio (VPM) elevado está associado com falha na fibrinólise e eventos adversos em pacientes com infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAMCSST). No entanto, não há dados sobre os efeitos do VPM sobre o fluxo sanguíneo coronariano anterógrado e o grau de reperfusão em pacientes com fibrinólise bem sucedida. Objetivo: O objetivo deste estudo foi investigar o papel do VMP sobre a circulação coronariana via contagem de quadros angiográficos (TFC) na trombólise no infarto do miocárdio (TIMI) após terapia fibrinolítica bem sucedida. Métodos: Entre 145 pacientes tratados com agentes fibrinolíticos, 123 (84,8%) pacientes consecutivos com fibrinólise bem sucedida, determinados por eletrocardiografia, foram incluídos. Os pacientes foram divididos em dois grupos de acordo com TFC. Um TCF > 40 foi considerado como um marcador de reperfusão inadequada, e um TCF ≤ 40 aceito como um indicador de reperfusão completa. Resultados: Após a angiografia coronária, 57 pacientes apresentaram TFC ≤ 40 e 66 pacientes apresentaram TFC > 40. O VPM foi significativamente mais alto no grupo com reperfusão inadequada (8,93 ± 0,87 fl vs. 7,92 ± 0,80 fl, p < 0,001). Um VPM elevado foi identificado como um indicador de reperfusão inadequada, e coordenadas da curva ROC indicaram um ponto de corte de 8,3 fl para VPM. Conclusão: VPM elevado na admissão em pacientes com IAMCSST tratados com terapia fibrinolítica bem sucedida associou-se com reperfusão inadequada detectada por TFC

Background: Higher Mean platelet volume (MPV) is associated with fibrinolysis failure and adverse outcomes in patients with ST elevation myocardial infarction (STEMI). However, there are no data about the effects of MPV on antegrade coronary blood flow and the degree of reperfusion in patients with successful fibrinolysis. Objective: The aim of our study was to investigate the role of MPV on coronary circulation via thrombolysis in myocardial infarction (TIMI) frame count (TFC) after successful fibrinolytic therapy. Methods: Among 145 patients treated with fibrinolytics, 123 (84.8%) consecutive patients with successful fibrinolysis determined by electrocardiography criteria were included. The patients were divided into two groups according to TFC. TFC > 40 was accepted as a marker for inadequate reperfusion and TFC ≤ 40 was accepted as an indicator of complete reperfusion. Results: After coronary angiography, 57 patients had TFC ≤ 40 and 66 patients had TFC > 40. MPV was significantly higher in the inadequate reperfusion group (8.93 ± 0.87 fl vs 7.92 ± 0.80 fl, p < 0.001). Higher MPV was found to be an indicator of inadequate reperfusion and coordinates of the ROC curve indicated a cutoff value of 8.3 fl for MPV. Conclusion: Higher MPV on admission in STEMI patients treated with successful fibrinolytic therapy was found to be associated with inadequate reperfusion detected by TFC

Terapia antitrombótica na fase aguda das síndromes coronarianas aguda / Antithrombotic therapy in acute phase of acute coronary syndrome

A morbidade e a mortalidade nas síndromes coronarianas agudas – causadas principalmente pela instabilidade da placa aterosclerótica, levando à formação de trombos – foi bastante reduzida com o advento de antiplaquetários, antitrombóticos e revascularização precoce. Hoje, dispomos de quatro antitrombóticos para uso nestas condições: a heparina não fracionada, a de baixo peso molecular, o fondaparinux e a bivalirudina – sendo apenas as três primeiras disponíveis no Brasil. Como são agentes antiocoagulantes, o risco de sangramento não é desprezível e deve ser apropriadamente dosado com o fim de trazer o máximo benefício antitrombótico, sem grande risco hemorrágico. Nesta revisão sumarizamos o atual estado da arteno uso de antitrombóticos no Brasil...

Morbidity and mortality in the acute coronary syndromes – caused in the majorly by atherosclerotic plaque instability, with consequent thrombus formation – was drastically reduced by the advent of antiplatelet and antithrombotic agents, and by early revascularization. Nowadays, we have 4 antithrombotic agents: unfractionated heparin, low molecular weight heparin, fondaparinux and bivalirudin – with only the first 3 available in Brazil. As they comprise anticoagulant effects, the risk of bleedingis high and must be taken into account when prescribed, in order to bring the greater benefits without higher bleeding risk. In this review we summarized the current state of the art about the use of these agents in our country...

Aterectomia rotacional multiarterial em lesão de tronco de coronária esquerda seguida de implante de stents / Multivessel rotational atherectomy in left main coronary artery lesion followed by stent implantation

Paciente com 82 anos, portadora de múltiplas comorbidades, com angina do peito apesar de terapia medicamentosa otimizada. Submetida à coronariografia, que evidenciou doença triarterial com envolvimento do tronco da coronária esquerda e intensa calcificação das artérias coronárias. A cirurgia de revascularização miocárdica foi contraindicada, sendo encaminhada para intervenção coronária percutânea, realizada em dois tempos, com intervalo de 15 meses. Primeiramente, a coronária esquerda foi abordada, realizando-se aterectomia rotacional no tronco da coronária esquerda, artérias descendente anterior e circunflexa, com implante de cinco stents farmacológicos com sucesso. Posteriormente, a coronária direita foi tratada com aterectomia rotacional e implante de quatro stents farmacológicos, também com sucesso

A 82-year-old patient with multiple comorbidities and angina, in spite of optimal drug therapy, was submitted to coronary angiography, which showed three-vessel disease with left main coronary artery involvement and severe coronary artery calcification. Coronary artery bypass grafting surgery was contraindicated and the patient was referred for percutaneous coronary intervention, which was carried out in two stages, with a 15-month interval between them. Firstly, the left coronary artery was treated and rotational atherectomy was performed in the left main coronary artery, left anterior descending and left circumflex arteries, with successful implantation of five drug-eluting stents. Subsequently, the right coronary artery was treated with rotational atherectomy, and four drug-eluting stents were also successfully implanted

Selective inactivation of NADPH oxidase 2 causes regression of vascularization and the size and stability of atherosclerotic plaques.

BACKGROUND: A variety of NADPH oxidase (Nox) isoforms including Noxs 1, 2, 4 and 5 catalyze the formation of reactive oxygen species (ROS) in the vascular wall. The Nox2 isoform complex has arguably received the greatest attention in the progression of atherogenesis in animal models. Thus, in the current study we postulated that specific Nox2 oxidase inhibition could reverse or attenuate atherosclerosis in mice fed a high-fat diet. METHODS: We evaluated the effect of isoform-selective Nox2 assembly inhibitor on the progression and vascularization of atheromatous plaques. Apolipoprotein E-deficient mice (ApoE-/-) were fed a high fat diet for two months and treated over 15 days with Nox2ds-tat or control sequence (scrambled); 10 mg/kg/day, i.p. Mice were sacrificed and superoxide production in arterial tissue was detected by cytochrome C reduction assay and dihydroethidium staining. Plaque development was evaluated and the angiogenic markers VEGF, HIF1-α and visfatin were quantified by real time qRT-PCR. MMP-9 protein release and gelatinolytic activity was determined as a marker for vascularization. RESULTS: Nox2ds-tat inhibited Nox-derived superoxide determined by cytochrome C in carotid arteries (2.3 ± 0.1 vs 1.7 ± 0.1 O2(•-) nmol/min*mg protein; P < 0.01) and caused a significant regression in atherosclerotic plaques in aorta (66 ± 6 µm(2) vs 37 ± 1 µm(2); scrmb vs. Nox2ds-tat; P < 0.001). Increased VEGF, HIF-1α, MMP-9 and visfatin expression in arterial tissue in response to high-fat diet were significantly attenuated by Nox2ds-tat which in turn impaired both MMP-9 protein expression and activity. CONCLUSION: Given these results, it is quite evident that selective Nox inhibitors can reverse vascular pathology arising with atherosclerosis.

Resultados do uso de stents de nitinol superflexíveis na artéria femoral superficial / Outcomes after implantation of superflexible nitinol stents in the superficial femoral artery

As intervenções endovasculares na artéria femoral superficial para o tratamento da doença arterial oclusiva periférica têm crescido nas últimas décadas. A primeira e a segunda geração de stents na artériafemoral superficial falharam em demonstrar a melhora da perviedade do vaso tratado, devido às altas taxas defratura. O objetivo deste estudo foi avaliar os desfechos clínicos no curto prazo com o uso de stents de nitinolsuperflexíveis de terceira geração no tratamento de lesões ateroscleróticas na artéria femoral superficial. Métodos: Trata-se de um estudo retrospectivo, realizado em único centro, no período de junho de 2013 a maio de 2014. Um total de 27 pacientes foi submetido à angioplastia com stents de nitinol superflexíveis de terceira geração em lesões ateroscleróticas da arterial femoral superficial. Resultados: A média de idades foi de 68 ± 12 anos, 55,6% eram do sexo feminino e 74,1%, diabéticos. Os pacientes foram classificados em TASC B e C em 77,7% dos casos. O sucesso técnico foi de 100%. Houve aumento do índice tornozelo-braquial de 0,35 ± 0,1 pré-intervenção para 0,75 ± 0,2 na alta hospitalar. O seguimento médio dos pacientes foi de 6,7 ± 2,3 meses. A taxa de patência primária foi de 96,3%. A taxa de salvamento de membro foi de 100%. Não ocorreram fraturas de stent documentadas por raios X. Conclusões: A angioplastia com uso de stent de nitinol superflexível de terceira geração demonstrou ser efetiva no tratamento das lesões ateroscleróricas da artéria femoral superficial...

Endovascular interventions in the superficial femoral artery for the treatment of peripheral arterial occlusive disease have increased over the last decades. The first- and second-generation stents in the superficial femoral artery have failed to demonstrate improved patency of the treated vessel due to high fracture rates. The aim of this study was to evaluate the clinical, short-term outcomes of using third-generation superflexible nitinol stents in the treatment of atherosclerotic lesions in the superficial femoral artery. Methods: This was a retrospective study carried out in a single center, from June 2013 to May 2014. A total of 27 patients underwent angioplasty with third-generation superflexible nitinol stents in atherosclerotic lesions of the superficial femoral artery. Results: The mean age was 68 ± 12 years, 55.6% were females, and 74.1% were diabetics. Patients were classified as TASC B and C in 77.7% of cases. Technical success was 100%. There was an increase in the anklebrachial index from 0.35 ± 0.1 before the intervention to 0.75 ± 0.2 at hospital discharge. The mean followupof patients was 6.7 ± 2.3 months. The primary patency rate was 96.3%. The limb salvage rate was 100%. There were no stent fractures documented by X-rays. Conclusions: Angioplasty with third-generation superflexible nitinol stent placement was shown to beeffective in the treatment of atherosclerotic lesions of the superficial femoral artery...

Avaliação da subtração do artefato do fio-guia na análise quantitativa e tecidualcom ultrassom intracoronário e tecnologia iMAP® em pacientes com síndrome coronária aguda: subanálise do estudo iWonder / Evaluation of guidewire artifact subtraction in quantitative and tissue analysis with intracoronary ultrasound and iMAPTM technology in patients presenting with acute coronary syndrome: an iWonder study subanalysis

O ultrassom intracoronário (USIC) é o método adjunto mais utilizado na Cardiologia Intervencionista, e sua análise depende de normas para a aquisição, mensuração e interpretação das imagens. Ao associar a caracterização tecidual, o artefato causado pelo fio-guia pode hiperestimaro porcentual de núcleo necrótico em determinadas lesões, levando à classificação equivocada defibroateroma. Descrevemos os efeitos quantitativos e na análise tecidual resultantes da subtração do efeitodo artefato do fio-guia nas lesões ateroscleróticas em pacientes com síndrome coronária aguda. Métodos: Foram avaliados 21 pacientes com infarto do miocárdio pós-trombólise com USIC em escala de cinzas e com a tecnologia iMAP®, totalizando 76 lesões.Resultados: O USIC em escala de cinzas mostrou que as lesões tinham extensão média de 21,01 ± 18,03 mm e apresentavam elevada carga de placa (52,07 ± 7,56%). A análise pelo iMAP® demonstrou que, após a subtração do artefato do fio-guia, houve redução de todos os componentes teciduais (necrótico, calcífico, lipídico e fibrótico), porém de maneira mais acentuada do núcleo necrótico (diferença média de 3,59%). Além disso, após a subtração do artefato, 12,4% das lesões que inicialmente apresentavam núcleo necrótico ≥ 10% passaram a não ser mais classificadas como fibroateroma.Conclusões: A análise da placa de ateroma pela tecnologia iMAP® mostrou que o artefato do fio-guia superestimou o componente tecidual do núcleo necrótico. Essa interferência pode mudar errônea e categoricamente as características fenotípicas de lesões mais benignas e estáveis (fibróticas) para lesões potencialmente instáveis, como os fibroateromas, na relação de um em cada dez pacientes...

Intravascular ultrasound (IVUS) is the most widely used ancillary method in Interventional Cardiology, and its analysis depends on standards for acquisition, measurement and interpretation of the images. By associating tissue characterization, the artifact caused by the guidewire may overestimate the percentage of necrotic core in certain lesions, leading to misclassification of fibroatheroma. In this paper we described quantitative and tissue analysis effects resulting from subtracting the effect of guidewire artifact on atherosclerotic lesions in patients with acute coronary syndrome. Methods: Twenty-one patients with post-thrombolysis myocardial infarction were evaluated with grayscale IVUS and iMAPTM technology, totaling 76 lesions. Results: Grayscale IVUS showed that the lesions had a mean length of 21.01 ± 18.03 mm and revealed highplaque burden (52.07 ± 7.56%). The analysis by iMAPTM demonstrated that, after subtracting the guidewire artifact, there was a reduction of all tissue (necrotic, calcific, lipid and fibrotic) components, but more markedly in necrotic core (mean difference: 3.59%). In addition, after artifact subtraction 12.4% of the lesions that initially exhibited a necrotic core ≥ 10% ceased to be classified as fibroatheroma.Conclusions: An atheroma analysis by iMAPTM technology showed that the guidewire artifact over estimated the tissue component of the necrotic core. This interference may change, in an erroneous and categoric alway, the phenotypic characteristics of more stable and benign (fibrotic) lesions to potentially unstable lesions, for example, fibroatheromas, in a ratio of one out of ten patients...

Effects of the simultaneous use of drug-eluting stents and statins in an atherosclerotic animal model.

INTRODUCTION: The use of statins and medicated stents (MS) is the best available therapy for the treatment of severe coronary disease in selected cases. However, the vascular effects of the simultaneous use of both therapies are unknown. MATERIALS AND METHODS: An experimental study was carried out on 60 NZ rabbits with advanced atherosclerosis, distributed in four groups of 15 animals each. Group 1: Control. Group 2: paclitaxel-eluting stent (PES) in the thoracic aorta. Group 3: Atorvastatin 2.5mg/day po+PES implant, and Group 4: Atorvastatin 2.5mg/day po. They were followed up at 30, 60 and 90 days. Histo-morphometric analyses were carried out. RESULTS: A total of 60 PES were successfully implanted. One animal from Group 3 died due to respiratory infection. PES increased the lumen diameter and area, as well as the vessel area; atorvastatin induced a potent plaque regression. In the PES group, the lumen diameter was 4.25±0.0mm, lumen area was 14.2±0.4mm(2), vessel area was 16.7±0.0mm(2), and plaque/media area ratio was 0.1±0.0. In the PES+atorvastatin group the measurements were 4.9±0.1mm (p<0.001), 18.6±0.8mm(2) (p=0.005), 21.6±0.9mm(2) (p=0.007) and 0.8±0.08 (p=0.032), respectively. CONCLUSIONS: Our results confirm the potent synergistic mechanical effect of the PES and plaque regression of the statins in an animal model with advanced atherosclerosis.

Avaliação angiográfica do volume de placa e eventos cardiovasculares após implante de stents coronarianos / Angiographic evaluation of plaque volume and cardiovascular events after coronary Stent Implantation / Evaluación angiográfica del volumen de placa y eventos cardiovasculares tras implantación de stents coronarios

FUNDAMENTO: O volume de placa (VP) está relacionado a eventos cardiovasculares maiores (ECVM) após o implante de stents coronarianos. OBJETIVO: Avaliar a associação entre o VP antes do procedimento avaliado por angiografia e desfechos clínicos. MÉTODOS: Trata-se de estudo de coorte prospectivo incluindo pacientes submetidos a implante de stents coronarianos em um centro de referência. O VP antes do implante do stent foi avaliado pela fórmula descrita por Giugliano (Am J Cardiol 2005; 95:173): VP = À X (comprimento da lesão) X [(diâmetro do vaso/2)² - (diâmetro luminal mínimo/2)²]. Os ECVM foram registrados no seguimento clínico de um ano e análise de regressão linear múltipla foi realizada para identificar os preditores de eventos. RESULTADOS: A amostra estudada consistiu em 824 pacientes, com idade média de 60 ± 11 anos, sendo 70,0 por cento do gênero masculino. O diabete melito estava presente em 21,0 por cento e o comprometimento triarterial em 12,0 por cento. O diâmetro médio de referência foi de 3,3 ± 3,2 mm, a média do comprimento da lesão foi de 10,2 ± 4,7 mm e a média da estenose residual foi de 1,0 por cento ± 12,0 por cento. Os pacientes com ECVM apresentaram VP maior do que aqueles sem eventos (92,84 ± 42,85 vs 85 ± 46,85; p = 0,03). Outras variáveis associadas com ECVM na análise univariada foram comprometimento triarterial, IAM, diâmetro do vaso e comprimento da lesão tratada. O VP manteve a associação significativa com ECVM após ajuste para as variáveis descritas e diabete melito. CONCLUSÃO: O volume da placa do ateroma antes do implante do stent foi maior nos pacientes que apresentaram ECVM no seguimento clínico em um ano, independentemente de outros preditores de eventos.

BACKGROUND: Plaque volume (PV) is related to major cardiovascular events (MACE) after coronary stent implantation. OBJECTIVE: To evaluate the association between PV before the procedure evaluated by angiography and clinical outcomes. METHODS: This is a prospective cohort study of patients undergoing coronary stent implantation in a referral center. PV before the stent implantation was evaluated by the formula described by Giugliano (Am J Cardiol 2005, 95:173): VP = À X (lesion length) X [(vessel diameter/2)² - (minimum luminal diameter/2)²]. The MACE were registered at clinical follow-up of one year and multiple linear regression analysis was performed to identify predictors of events. RESULTS: The sample consisted of 824 patients, mean age 60 ± 11 years, 70.0 percent were male. Diabetes mellitus was present in 21.0 percent and triple vessel involvement in 12.0 percent. Average reference diameter was 3.3 ± 3.2 mm, average lesion length was 10.2 ± 4.7 mm and mean residual stenosis was 1.0 percent ± 12.0 percent. Patients with MACE had higher PV than those without events (92.84 ± 42.85 vs 85 ± 46.85, p = 0.03). Other variables associated with MACE in the univariate analysis were triple vessel involvement, myocardial infarction, vessel diameter and length of the lesion treated. PV maintained a significant association with MACE after adjusting for the variables described and diabetes mellitus. CONCLUSION: The volume of atheromatous plaque before stenting was higher in patients with MACE on clinical follow-up in one year, regardless of other predictors of events.

FUNDAMENTO: El volumen de placa (VP) está relacionado a eventos cardiovasculares mayores (ECVM) tras implantación de stentscoronarios. OBJETIVOS: Evaluar la asociación entre el VP antes del procedimiento evaluado por angiografía y desenlaces clínicos. MÉTODOS: Se trata de estudio de cohorte prospectivo que incluye a pacientes sometidos a implantación de stentscoronarios en un centro de referencia. El VP antes de la implantación del stent se evaluó por la fórmula descrita por Giugliano (Am J Cardiol 2005; 95:173): VP = Π X (longitud de la lesión) X [(diámetro del vaso/2)² - (diámetro luminal mínimo/2)²]. Los ECVM fueron registrados en el seguimiento clínico de un año y análisis de regresión lineal múltiple se llevó a cabo para identificar los predictores de eventos. RESULTADOS: La muestra estudiada consistió en 824 pacientes, con edad promedio de 60 ± 11 años, con el 70 por ciento del género masculino. El diabetes melito estaba presente en el 21,0 por ciento y el compromiso triarterial en el 12 por ciento. El diámetro medio de referencia fue de 3,3 ± 3,2 mm, la media del longitud de la lesión fue de 10,2 ± 4,7 mm y la media de la estenosis residual fue del 1 por ciento ± 12 por ciento. Los pacientes con ECVM presentaron VP mayor que aquellos sin eventos (92,84 ± 42,85 vs 85 ± 46,85; p = 0,03). Otras variables asociadas con ECVM en el análisis univariado fueron el compromiso triarterial, el IAM, el diámetro del vaso y longitud de la lesión tratada. El VP mantuvo la asociación significativa con ECVM tras ajuste para las variables descritas y diabetes melito. CONCLUSIÓN: El volumen de la placa del ateroma antes de la implantación del stent fue mayor en los pacientes que presentaron ECVM en el seguimiento clínico en un año, independientemente de otros predictores de eventos.

Angiographic evaluation of plaque volume and cardiovascular events after coronary stent implantation.

BACKGROUND: Plaque volume (PV) is related to major cardiovascular events (MACE) after coronary stent implantation. OBJECTIVE: To evaluate the association between PV before the procedure evaluated by angiography and clinical outcomes. METHODS: This is a prospective cohort study of patients undergoing coronary stent implantation in a referral center. PV before the stent implantation was evaluated by the formula described by Giugliano (Am J Cardiol 2005, 95:173): VP = π X (lesion length) X [(vessel diameter/2)² - (minimum luminal diameter/2)²]. The MACE were registered at clinical follow-up of one year and multiple linear regression analysis was performed to identify predictors of events. RESULTS: The sample consisted of 824 patients, mean age 60 ± 11 years, 70.0% were male. Diabetes mellitus was present in 21.0% and triple vessel involvement in 12.0%. Average reference diameter was 3.3 ± 3.2 mm, average lesion length was 10.2 ± 4.7 mm and mean residual stenosis was 1.0% ± 12.0%. Patients with MACE had higher PV than those without events (92.84 ± 42.85 vs 85 ± 46.85, p = 0.03). Other variables associated with MACE in the univariate analysis were triple vessel involvement, myocardial infarction, vessel diameter and length of the lesion treated. PV maintained a significant association with MACE after adjusting for the variables described and diabetes mellitus. CONCLUSION: The volume of atheromatous plaque before stenting was higher in patients with MACE on clinical follow-up in one year, regardless of other predictors of events.