A erradicaçao da síncope vasovagal maligna pela estimulaçao cardíaca artificial

Reaçoes vasovagais intensas podem ocorrer em indivíduos sadios expostos a emoçoes fortes e súbitas, como medo, dor e frustraçao. O objetivo do presente trabalho é o relato do caso de um paciente que após estímulos emocionais apresentou dois episódios de síncope e parada cardíaca, necessitando de massagem cardíaca externa. Um homem de 46 anos apresentou sintomas pré-sincopais em uma consulta médica de rotina, durante a medida de sua pressao arterial. Diante desse quadro, o paciente foi monitorizado, porém sua condiçao se deteriorou rapidamente, com aumento da ansiedade, sendo constatado um período de assistolia e síncope que necessitou de massagem cardíaca externa para sua reversao. Transferido para o hospital, foi mantido sob monitorizaçao contínua. Na realizaçao de punçao venosa para colheita de exames, apresentou nova assistolia e síncope, mais uma vez necessitando de massagem cardíaca externa. Na história pregressa, o paciente relatou outros episódios pré-sincopais em situaçoes de tensao emocional. O Holter de 24 horas, período no qual nao houve estímulo emocional importante, foi normal. O Ecocardiograma também nao apresentou anormalidades.

Deep learning segmentation of fibrous cap in intravascular optical coherence tomography images

Thin-cap fibroatheroma (TCFA) is a prominent risk factor for plaque rupture. Intravascular optical coherence tomography (IVOCT) enables identification of fibrous cap (FC), measurement of FC thicknesses, and assessment of plaque vulnerability. We developed a fully-automated deep learning method for FC segmentation. This study included 32,531 images across 227 pullbacks from two registries. Images were semi-automatically labeled using our OCTOPUS with expert editing using established guidelines. We employed preprocessing including guidewire shadow detection, lumen segmentation, pixel-shifting, and Gaussian filtering on raw IVOCT (r,theta) images. Data were augmented in a natural way by changing theta in spiral acquisitions and by changing intensity and noise values. We used a modified SegResNet and comparison networks to segment FCs. We employed transfer learning from our existing much larger, fully-labeled calcification IVOCT dataset to reduce deep-learning training. Overall, our method consistently delivered better FC segmentation results (Dice: 0.837+/-0.012) than other deep-learning methods. Transfer learning reduced training time by 84% and reduced the need for more training samples. Our method showed a high level of generalizability, evidenced by highly-consistent segmentations across five-fold cross-validation (sensitivity: 85.0+/-0.3%, Dice: 0.846+/-0.011) and the held-out test (sensitivity: 84.9%, Dice: 0.816) sets. In addition, we found excellent agreement of FC thickness with ground truth (2.95+/-20.73 um), giving clinically insignificant bias. There was excellent reproducibility in pre- and post-stenting pullbacks (average FC angle: 200.9+/-128.0 deg / 202.0+/-121.1 deg). Our method will be useful for multiple research purposes and potentially for planning stent deployments that avoid placing a stent edge over an FC.Comment: 24 pages, 9 figures, 2 tables, 2 supplementary figures, 3 supplementary table

Automated analysis of fibrous cap in intravascular optical coherence tomography images of coronary arteries

Thin-cap fibroatheroma (TCFA) and plaque rupture have been recognized as the most frequent risk factor for thrombosis and acute coronary syndrome. Intravascular optical coherence tomography (IVOCT) can identify TCFA and assess cap thickness, which provides an opportunity to assess plaque vulnerability. We developed an automated method that can detect lipidous plaque and assess fibrous cap thickness in IVOCT images. This study analyzed a total of 4,360 IVOCT image frames of 77 lesions among 41 patients. To improve segmentation performance, preprocessing included lumen segmentation, pixel-shifting, and noise filtering on the raw polar (r, theta) IVOCT images. We used the DeepLab-v3 plus deep learning model to classify lipidous plaque pixels. After lipid detection, we automatically detected the outer border of the fibrous cap using a special dynamic programming algorithm and assessed the cap thickness. Our method provided excellent discriminability of lipid plaque with a sensitivity of 85.8% and A-line Dice coefficient of 0.837. By comparing lipid angle measurements between two analysts following editing of our automated software, we found good agreement by Bland-Altman analysis (difference 6.7+/-17 degree; mean 196 degree). Our method accurately detected the fibrous cap from the detected lipid plaque. Automated analysis required a significant modification for only 5.5% frames. Furthermore, our method showed a good agreement of fibrous cap thickness between two analysts with Bland-Altman analysis (4.2+/-14.6 micron; mean 175 micron), indicating little bias between users and good reproducibility of the measurement. We developed a fully automated method for fibrous cap quantification in IVOCT images, resulting in good agreement with determinations by analysts. The method has great potential to enable highly automated, repeatable, and comprehensive evaluations of TCFAs.Comment: 18 pages, 9 figure

Neoatherosclerosis prediction using plaque markers in intravascular optical coherence tomography images

IntroductionIn-stent neoatherosclerosis has emerged as a crucial factor in post-stent complications including late in-stent restenosis and very late stent thrombosis. In this study, we investigated the ability of quantitative plaque characteristics from intravascular optical coherence tomography (IVOCT) images taken just prior to stent implantation to predict neoatherosclerosis after implantation.MethodsThis was a sub-study of the TRiple Assessment of Neointima Stent FOrmation to Reabsorbable polyMer with Optical Coherence Tomography (TRANSFORM-OCT) trial. Images were obtained before and 18 months after stent implantation. Final analysis included images of 180 lesions from 90 patients; each patient had images of two lesions in different coronary arteries. A total of 17 IVOCT plaque features, including lesion length, lumen (e.g., area and diameter); calcium (e.g., angle and thickness); and fibrous cap (FC) features (e.g., thickness, surface area, and burden), were automatically extracted from the baseline IVOCT images before stenting using dedicated software developed by our group (OCTOPUS). The predictive value of baseline IVOCT plaque features for neoatherosclerosis development after stent implantation was assessed using univariate/multivariate logistic regression and receiver operating characteristic (ROC) analyses.ResultsFollow-up IVOCT identified stents with (n = 19) and without (n = 161) neoatherosclerosis. Greater lesion length and maximum calcium angle and features related to FC were associated with a higher prevalence of neoatherosclerosis after stent implantation (p < 0.05). Hierarchical clustering identified six clusters with the best prediction p-values. In univariate logistic regression analysis, maximum calcium angle, minimum calcium thickness, maximum FC angle, maximum FC area, FC surface area, and FC burden were significant predictors of neoatherosclerosis. Lesion length and features related to the lumen were not significantly different between the two groups. In multivariate logistic regression analysis, only larger FC surface area was strongly associated with neoatherosclerosis (odds ratio 1.38, 95% confidence interval [CI] 1.05–1.80, p < 0.05). The area under the ROC curve was 0.901 (95% CI 0.859–0.946, p < 0.05) for FC surface area.ConclusionPost-stent neoatherosclerosis can be predicted by quantitative IVOCT imaging of plaque characteristics prior to stent implantation. Our findings highlight the additional clinical benefits of utilizing IVOCT imaging in the catheterization laboratory to inform treatment decision-making and improve outcomes

InsCor: A Simple and Accurate Method for Risk Assessment in Heart Surgery

FUNDAMENTO: Escores de risco apresentam dificuldades para obter o mesmo desempenho em diferentes populações. OBJETIVO: Criar um modelo simples e acurado para avaliação do risco nos pacientes operados de doença coronariana e/ou valvar no Instituto do Coração da Universidade de São Paulo (InCor-HCFMUSP). MÉTODOS: Entre 2007 e 2009, 3.000 pacientes foram operados consecutivamente de doença coronariana e/ou valvar no InCor-HCFMUSP. Desse registro, dados de 2/3 dos pacientes foram utilizados para desenvolvimento do modelo (técnica de bootstrap) e de 1/3 para validação interna do modelo. O desempenho do modelo (InsCor) foi comparado aos complexos 2000 Bernstein-Parsonnet (2000BP) e EuroSCORE (ES). RESULTADOS: Apenas 10 variáveis foram selecionadas: Idade > 70 anos; sexo feminino; cirurgia de revascularização coronariana + valva; infarto de miocárdio < 90 dias; reoperação; tratamento cirúrgico da valva aórtica; tratamento cirúrgico da valva tricúspide; creatinina < 2mg/dL; fração de ejeção < 30%; e eventos. O teste de Hosmer Lemeshow para o InsCor foi de 0,184, indicando uma excelente calibração. A área abaixo da curva ROC foi de 0,79 para o InsCor, 0,81 para o ES e 0,82 para o 2000BP, confirmando que os modelos são bons e similares na discriminação. CONCLUSÕES: O InsCor e o ES tiveram melhor desempenho que o 2000BP em todas as fases da validação; pórem o novo modelo, além de se identificar com os fatores de risco locais, é mais simples e objetivo para a predição de mortalidade nos pacientes operados de doença coronariana e/ou valvar no InCor-HCFMUSP

Keratinocyte growth factor: a new mesothelial targeted therapy to reduce postoperative pericardial adhesions

Background: Several methods have been utilized to prevent pericardial and retrosternal adhesions, but none of them evaluated the mesothelial regenerative hypothesis. There are evidences that the mesothelial trauma reduces pericardial fibrinolytic capability and induces an adhesion process. Keratinocyte growth factor (KGF) has proven to improve mesothelial cells proliferation. This study investigated the influence of keratinocyte growth factor in reducing post-surgical adhesions. Methods: Twelve pigs were operated and an adhesion protocol was employed. Following a stratified randomization, the animals received a topical application of KGF or saline. At 8 weeks, intrapericardial adhesions were evaluated and a severity score was established. The time spent to dissect the adhesions and the amount of sharp dissection used, were recorded. Histological sections were stained with sirius red and morphometric analyses were assessed with a computer-assisted image analysis system. Results: The severity score was lower in the KGF group than in the control group (11.5 vs 17, p = 0.005). The dissection time was lower in the KGF group (9.2 +/- 1.4 min vs 33.9 +/- 9.2 min, p = 0.004) and presented a significant correlation with the severity score (r = 0.83, p = 0.001). A significantly less sharp dissection was also required in the KGF group. Also, adhesion area and adhesion collagen were significantly tower in the KGF group than in the control group. Conclusion: The simulation of pericardial cells with KGF reduced the intensity of postoperative adhesions and facilitated the re-operation. This study suggests that the mesothelial regeneration is the new horizon in anti-adhesion therapies. (C) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved

InsCor: um método simples e acurado para avaliação do risco em cirurgia cardíaca InsCor: a simple and accurate method for risk assessment in heart surgery

FUNDAMENTO: Escores de risco apresentam dificuldades para obter o mesmo desempenho em diferentes populações. OBJETIVO: Criar um modelo simples e acurado para avaliação do risco nos pacientes operados de doença coronariana e/ou valvar no Instituto do Coração da Universidade de São Paulo (InCor-HCFMUSP). MÉTODOS: Entre 2007 e 2009, 3.000 pacientes foram operados consecutivamente de doença coronariana e/ou valvar no InCor-HCFMUSP. Desse registro, dados de 2/3 dos pacientes foram utilizados para desenvolvimento do modelo (técnica de bootstrap) e de 1/3 para validação interna do modelo. O desempenho do modelo (InsCor) foi comparado aos complexos 2000 Bernstein-Parsonnet (2000BP) e EuroSCORE (ES). RESULTADOS: Apenas 10 variáveis foram selecionadas: Idade > 70 anos; sexo feminino; cirurgia de revascularização coronariana + valva; infarto de miocárdio < 90 dias; reoperação; tratamento cirúrgico da valva aórtica; tratamento cirúrgico da valva tricúspide; creatinina < 2mg/dL; fração de ejeção < 30%; e eventos. O teste de Hosmer Lemeshow para o InsCor foi de 0,184, indicando uma excelente calibração. A área abaixo da curva ROC foi de 0,79 para o InsCor, 0,81 para o ES e 0,82 para o 2000BP, confirmando que os modelos são bons e similares na discriminação. CONCLUSÕES: O InsCor e o ES tiveram melhor desempenho que o 2000BP em todas as fases da validação; pórem o novo modelo, além de se identificar com os fatores de risco locais, é mais simples e objetivo para a predição de mortalidade nos pacientes operados de doença coronariana e/ou valvar no InCor-HCFMUSP.<br>BACKGROUND: Risk scores show difficulties to attain the same performance in different populations. OBJECTIVE: To create a simple and accurate risk assessment model for patients submitted to surgery due to coronary and/or valvular disease at Instituto do Coração da Universidade de São Paulo (InCor-HCFMUSP). METHODS: Between 2007 and 2009, 3,000 patients were submitted to surgical procedure due to coronary artery and/or valvular disease at InCor-HCFMUSP. From this record, data of 2/3 of the patients were used for model development (bootstrap technique), and 1/3 for internal validation of the model. The performance of the model (InsCor) was compared to the 2000 Bernstein-Parsonnet (2000BP) and EuroSCORE (ES) complexes. RESULTS: Only 10 variables were selected: age > 70 years, female sex; coronary revascularization + valve, myocardial infarction < 90 days; reoperation; surgical treatment of aortic valve; surgical treatment of tricuspid valve; creatinine < 2mg/dL; ejection fraction < 30%, and events. The Hosmer Lemeshow test for the InsCor was 0.184, indicating excellent calibration. The area under the ROC curve was 0.79 for the InsCor, 0.81 for the ES and 0.82 for 2000BP, confirming that the models are good and have similar discrimination. CONCLUSIONS: The InsCor and ES performed better than 2000BP at all stages of validation, but the new model, in addition to showing identification with the local risk factors, is simpler and more objective for mortality prediction in patients undergoing surgery due to coronary and/or valvular disease at InCor-HCFMUSP

Elective vs non-elective radial artery grafts: comparing midterm results through 64-Slice computed tomography Enxertos de artéria radial eletivos vs emergência: comparando resultados em seguimento a médio prazo

BACKGROUND: Left internal thoracic artery to left anterior descending artery (LITA-LADA) grafting has become a fundamental part of the coronary artery bypass graft procedure (CABG). This grafting in turn has led to an increased use of other arterial conduits, of which the radial artery (RA) is most popular. Whether RA grafting can be used in the emergency patient is controversial. METHODS: 47 patients with critical stenosis (>70%) in all target vessels underwent CABG with LITA and RA grafts from 1996 to 2003. Patients were divided into elective (23 patients) and non-elective groups (24 patients) with LITA and RA grafts per patient being similar in both groups. Of these 47 patients, 5 died from non-cardiac complications and 12 were unavailable. Thus, 30 patients (71% of survivors) were studied by multidetector computed tomography. A total of 36 LITA and 64 RA grafts were studied. RESULTS: The RA patency rate for elective and non-elective grafts were 82% (31/38) and 85% (22/26), respectively (p=0.75). The RA had a similar patency rate for all target vessels ranging from 73% to 100%. Only one patient had a redo CABG and 29 (97%) are free from angina or re-intervention. LITA-LADA had a 92% (11/12) and 100% (10/10) patency rate for elective and non-elective groups, respectively (p=0.37). The sequential LITA-diagonal-LADA in the elective group had a 50% (03/06) patency rate, which was significantly lower than the 100% (08/08) patency rate of the non-elective group (p=0.02). CONCLUSION: Radial Artery grafts can be used in both elective and non-elective patients with excellent results.<br>INTRODUÇÃO: A anastomose da artéria torácica interna esquerda com a artéria descendente anterior (ATIE-DA) se tornou parte fundamental da cirurgia de revascularização do miocárdio (RM). Esta técnica levou ao aumento de utilização de outros enxertos arteriais, entre os quais, a artéria radial (AR) é muito usasa. Na literatura há controvérsia se a AR pode ser usada em pacientes em RM de emergência. MÉTODOS: 47 pacientes com lesões críticas (>70%) em todas as artérias alvo foram submetidos à RM com ATIE e a AR entre 1996 e 2003. Os pacientes foram agrupados em eletivos (23 pacientes) e não eletivos (24 pacientes) sendo similares para número de enxertos de ATIE e AR por paciente. Dos 47 pacientes, 5 morreram de complicações não cardíacas e 12 não estavam disponíveis. Portanto, 30 pacientes (71% dos sobreviventes) foram estudados com tomografia computadorizada. Um total de 36 ATIE e 64 AR foram analisadas. RESULTADOS: a perviabilidade da AR nos grupos eletivo e não eletivo foram respectivamente 82% (31/38) e 85% (22/26) (p=0,75). A AR teve perviabilidade semelhante para todas as artérias alvo variando de 73% a 100%. Apenas um paciente foi submetido à nova RM e 29 (97%) estão livres de angina ou nova re-intervenção. ATIE-DA teve perviabilidade de 92% (11/12) e 100% (10/10) respectivamente nos grupos eletivo e não-eletivo (p=0,37). ATIE-Diagonal-DA seqüencial obteve perviabilidade de 50% (03/06) no grupo eletivo que foi significativamente menor que a perviabilidade de 100% (08/08) do não-eletivo (p=0,02). CONCLUSÃO: A AR pode ser utilizada nos pacientes eletivos e não eletivos com excelentes resultados