Inflammatory Modifications in Paranasal Sinuses and Ostiomeatal Complex Anatomical Variations in Jet Aircraft Pilots: A Computed Tomography Study.

Introduction Jet aircraft pilots are exposed to huge pressure variation during flight, which affect physiological functions as systems, such as the respiratory system. Objectives The objective of the present investigation was to evaluate inflammatory changes of paranasal sinuses of jet aircraft pilots before and after a jet aircraft training program, using multislice computed tomography (CT), in comparison with a group of nonairborne individuals with the same age, sex, and physical health conditions. A second objective of the present study was to assess the association between the ostiomeatal complex obstruction and its anatomical variations. Methods The study group consisted of 15 jet aircraft pilots participating in the training program. The control group consisted of 41 nonairborne young adults. The 15 fighter pilots were evaluated before initiating the training program and after their final approval for the presence of inflammatory paranasal sinus disease. The ostiomeatal complex anatomical variations and obstructions were analyzed in pilots after the training program. Results Jet aircraft pilots presented higher incidence of mucosal thickening in maxillary sinus and anterior ethmoid cells than controls. Prominent ethmoidal bulla showed significant association with obstruction of the osteomeatal complex. Conclusions Jet aircraft pilots present increased inflammatory disease when compared with nonairborne individuals. The presence of a prominent ethmoidal bulla is associated with ostiomeatal complex obstruction.

Chronic troponin elevation assessed by myocardial T1 mapping in patients with stable coronary artery disease.

BACKGROUND: Cardiac troponin detected with sensitive assays can be chronically elevated, in the absence of unstable coronary syndromes. In patients with chronic coronary artery disease, clinically silent ischemic episodes may cause chronic troponin release. T1 mapping is a cardiovascular magnetic resonance technique useful in quantitative cardiac tissue characterization. We selected patients with anatomically and functionally normal hearts to investigate associations between chronic troponin release and myocardial tissue characteristics assessed by T1 mapping. METHODS: We investigated the relationship between cardiac troponin I concentrations and cardiovascular magnetic resonance T1 mapping parameters in patients with stable coronary artery disease enrolled in MASS V study before elective revascularization. Participants had no previous myocardial infarction, negative late gadolinium enhancement, normal left ventricular function, chamber dimensions and wall thickness. RESULTS: A total of 56 patients were analyzed in troponin tertiles: nativeT1 and extracellular volume (ECV) values (expressed as means ±â€…standard deviations) increased across tertiles: nativeT1 (1006 ±â€…27 ms vs 1016 ±â€…27 ms vs 1034 ±â€…37 ms, ptrend = 0.006) and ECV (22 ±â€…3% vs 23 ±â€…1.9% vs 25 ±â€…3%, ptrend = 0.007). Cardiac troponin I concentrations correlated with native T1(R = 0.33, P = .012) and ECV (R = 0.3, P = .025), and were independently associated with nativeT1 (P = .049) and ventricular mass index (P = .041) in multivariable analysis. CONCLUSION: In patients with chronic coronary artery disease and structurally normal hearts, troponin I concentrations correlated with T1 mapping parameters, suggesting that diffuse edema or fibrosis scattered in normal myocardium might be associated with chronic troponin release.

Diagnostic Performance of a Machine Learning-Based CT-Derived FFR in Detecting Flow-Limiting Stenosis. / Performance Diagnóstica da FFR por Angiotomografia de Coronárias através de Software Baseado em Inteligência Artificial.

BACKGROUND: The non-invasive quantification of the fractional flow reserve (FFRCT) using a more recent version of an artificial intelligence-based software and latest generation CT scanner (384 slices) may show high performance to detect coronary ischemia. OBJECTIVES: To evaluate the diagnostic performance of FFRCT for the detection of significant coronary artery disease (CAD) in contrast to invasive FFR (iFFR) using previous generation CT scanners (128 and 256- detector rows). METHODS: Retrospective study with patients referred to coronary artery CT angiography (CTA) and catheterization (iFFR) procedures. Siemens Somatom Definition Flash (256-detector rows) and AS+ (128-detector rows) CT scanners were used to acquire the images. The FFRCT and the minimal lumen area (MLA) were evaluated using a dedicated software (cFFR version 3.0.0, Siemens Healthineers, Forchheim, Germany). Obstructive CAD was defined as CTA lumen reduction ≥ 50%, and flow-limiting stenosis as iFFR ≤0.8. All reported P values are two-tailed, and when <0.05, they were considered statistically significant. RESULTS: Ninety-three consecutive patients (152 vessels) were included. There was good agreement between FFRCT and iFFR, with minimal FFRCT overestimation (bias: -0.02; limits of agreement:0.14-0.09). Different CT scanners did not modify the association between FFRCT and FFRi (p for interaction=0.73). The performance of FFRCT was significantly superior compared to the visual classification of coronary stenosis (AUC 0.93vs.0.61, p<0.001) and to MLA (AUC 0.93vs.0.75, p<0.001), reducing the number of false-positive cases. The optimal cut-off point for FFRCT using a Youden index was 0.85 (87% Sensitivity, 86% Specificity, 73% PPV, 94% NPV), with a reduction of false-positives. CONCLUSION: Machine learning-based FFRCT using previous generation CT scanners (128 and 256-detector rows) shows good diagnostic performance for the detection of CAD, and can be used to reduce the number of invasive procedures.

FUNDAMENTO: A quantificação não invasiva da reserva fracionada de fluxo miocárdico (FFR TC ) através de software baseado em inteligência artificial em versão mais atualizada e tomógrafo de última geração (384 cortes) apresenta elevada performance na detecção de isquemia coronariana. OBJETIVOS: Avaliar o desempenho diagnóstico da FFR TC na detecção de doença arterial coronariana (DAC) significativa em relação ao FFRi, em tomógrafos de gerações anteriores (128 e 256 cortes). MÉTODOS: Estudo retrospectivo com pacientes encaminhados à angiotomografia de artérias coronárias (TCC) e cateterismo (FFRi). Foram utilizados os tomógrafos Siemens Somatom Definition Flash (256 cortes) e AS+ (128 cortes). A FFR TC e a área luminal mínima (ALM) foram avaliadas em software (cFFR versão 3.0.0, Siemens Healthineers, Forchheim, Alemanha). DAC obstrutiva foi definida como TCC com redução luminal ≥50% e DAC funcionalmente obstrutiva como FFRi ≤0,8. Todos os valores de p reportados são bicaudais; e quando <0,05, foram considerados estatisticamente significativos. RESULTADOS: Noventa e três pacientes consecutivos (152 vasos) foram incluídos. Houve boa concordância entre FFR TC e FFRi, com mínima superestimação da FFR TC (viés: ­0,02; limites de concordância: 0,14 a 0,09). Diferentes tomógrafos não modificaram a relação entre FFR TC e FFRi (p para interação = 0,73). A FFR TC demonstrou performance significativamente superior à classificação visual de estenose coronariana (AUC 0,93 vs. 0,61, p <0,001) e à ALM (AUC 0,93 vs. 0,75, p <0,001) reduzindo o número de casos falso-positivos. O melhor ponto de corte para a FFR TC utilizando um índice de Youden foi de 0,85 (sensiblidade, 87%; especificidade, 86%; VPP, 73%; NPV, 94%), com redução de falso-positivos. CONCLUSÃO: FFR TC baseada em inteligência artificial, em tomógrafos de gerações anteriores (128 e 256 cortes), apresenta boa performance diagnóstica na detecção de DAC, podendo ser utilizada para reduzir procedimentos invasivos.

Performance Diagnóstica da FFR por Angiotomografia de Coronárias através de Software Baseado em Inteligência Artificial / Diagnostic Performance of a Machine Learning-Based CT-Derived FFR in Detecting Flow-Limiting Stenosis

Resumo Fundamento A quantificação não invasiva da reserva fracionada de fluxo miocárdico (FFR TC ) através de software baseado em inteligência artificial em versão mais atualizada e tomógrafo de última geração (384 cortes) apresenta elevada performance na detecção de isquemia coronariana. Objetivos Avaliar o desempenho diagnóstico da FFR TC na detecção de doença arterial coronariana (DAC) significativa em relação ao FFRi, em tomógrafos de gerações anteriores (128 e 256 cortes). Métodos Estudo retrospectivo com pacientes encaminhados à angiotomografia de artérias coronárias (TCC) e cateterismo (FFRi). Foram utilizados os tomógrafos Siemens Somatom Definition Flash (256 cortes) e AS+ (128 cortes). A FFR TC e a área luminal mínima (ALM) foram avaliadas em software (cFFR versão 3.0.0, Siemens Healthineers, Forchheim, Alemanha). DAC obstrutiva foi definida como TCC com redução luminal ≥50% e DAC funcionalmente obstrutiva como FFRi ≤0,8. Todos os valores de p reportados são bicaudais; e quando <0,05, foram considerados estatisticamente significativos. Resultados Noventa e três pacientes consecutivos (152 vasos) foram incluídos. Houve boa concordância entre FFR TC e FFRi, com mínima superestimação da FFR TC (viés: -0,02; limites de concordância: 0,14 a 0,09). Diferentes tomógrafos não modificaram a relação entre FFR TC e FFRi (p para interação = 0,73). A FFR TC demonstrou performance significativamente superior à classificação visual de estenose coronariana (AUC 0,93 vs. 0,61, p <0,001) e à ALM (AUC 0,93 vs. 0,75, p <0,001) reduzindo o número de casos falso-positivos. O melhor ponto de corte para a FFR TC utilizando um índice de Youden foi de 0,85 (sensiblidade, 87%; especificidade, 86%; VPP, 73%; NPV, 94%), com redução de falso-positivos. Conclusão FFR TC baseada em inteligência artificial, em tomógrafos de gerações anteriores (128 e 256 cortes), apresenta boa performance diagnóstica na detecção de DAC, podendo ser utilizada para reduzir procedimentos invasivos.

Abstract Background The non-invasive quantification of the fractional flow reserve (FFRCT) using a more recent version of an artificial intelligence-based software and latest generation CT scanner (384 slices) may show high performance to detect coronary ischemia. Objectives To evaluate the diagnostic performance of FFRCT for the detection of significant coronary artery disease (CAD) in contrast to invasive FFR (iFFR) using previous generation CT scanners (128 and 256- detector rows). Methods Retrospective study with patients referred to coronary artery CT angiography (CTA) and catheterization (iFFR) procedures. Siemens Somatom Definition Flash (256-detector rows) and AS+ (128-detector rows) CT scanners were used to acquire the images. The FFRCT and the minimal lumen area (MLA) were evaluated using a dedicated software (cFFR version 3.0.0, Siemens Healthineers, Forchheim, Germany). Obstructive CAD was defined as CTA lumen reduction ≥ 50%, and flow-limiting stenosis as iFFR ≤0.8. All reported P values are two-tailed, and when <0.05, they were considered statistically significant. Results Ninety-three consecutive patients (152 vessels) were included. There was good agreement between FFRCT and iFFR, with minimal FFRCT overestimation (bias: -0.02; limits of agreement:0.14-0.09). Different CT scanners did not modify the association between FFRCT and FFRi (p for interaction=0.73). The performance of FFRCT was significantly superior compared to the visual classification of coronary stenosis (AUC 0.93vs.0.61, p<0.001) and to MLA (AUC 0.93vs.0.75, p<0.001), reducing the number of false-positive cases. The optimal cut-off point for FFRCT using a Youden index was 0.85 (87% Sensitivity, 86% Specificity, 73% PPV, 94% NPV), with a reduction of false-positives. Conclusion Machine learning-based FFRCT using previous generation CT scanners (128 and 256-detector rows) shows good diagnostic performance for the detection of CAD, and can be used to reduce the number of invasive procedures.

Biventricular imaging markers to predict outcomes in non-compaction cardiomyopathy: a machine learning study.

AIMS: Left ventricular non-compaction cardiomyopathy (LVNC) is a genetic heart disease, with heart failure, arrhythmias, and embolic events as main clinical manifestations. The goal of this study was to analyse a large set of echocardiographic (echo) and cardiac magnetic resonance imaging (CMRI) parameters using machine learning (ML) techniques to find imaging predictors of clinical outcomes in a long-term follow-up of LVNC patients. METHODS AND RESULTS: Patients with echo and/or CMRI criteria of LVNC, followed from January 2011 to December 2017 in the heart failure section of a tertiary referral cardiologic hospital, were enrolled in a retrospective study. Two-dimensional colour Doppler echocardiography and subsequent CMRI were carried out. Twenty-four hour Holter monitoring was also performed in all patients. Death, cardiac transplantation, heart failure hospitalization, aborted sudden cardiac death, complex ventricular arrhythmias (sustained and non-sustained ventricular tachycardia), and embolisms (i.e. stroke, pulmonary thromboembolism and/or peripheral arterial embolism) were registered and were referred to as major adverse cardiovascular events (MACEs) in this study. Recruited for the study were 108 LVNC patients, aged 38.3 ± 15.5 years, 48.1% men, diagnosed by echo and CMRI criteria. They were followed for 5.8 ± 3.9 years, and MACEs were registered. CMRI and echo parameters were analysed via a supervised ML methodology. Forty-seven (43.5%) patients had at least one MACE. The best performance of imaging variables was achieved by combining four parameters: left ventricular (LV) ejection fraction (by CMRI), right ventricular (RV) end-systolic volume (by CMRI), RV systolic dysfunction (by echo), and RV lower diameter (by CMRI) with accuracy, sensitivity, and specificity rates of 75.5%, 77%, 75%, respectively. CONCLUSIONS: Our findings show the importance of biventricular assessment to detect the severity of this cardiomyopathy and to plan for early clinical intervention. In addition, this study shows that even patients with normal LV function and negative late gadolinium enhancement had MACE. ML is a promising tool for analysing a large set of parameters to stratify and predict prognosis in LVNC patients.

Evaluation of Myocardial Perfusion by Computed Tomography - Principles, Technical Background and Recommendations.

Coronary computed tomography angiography (CCTA) has gained a prominent role in the evaluation of coronary artery disease. However, its anatomical nature does not allow the evaluation of the functional repercussion of coronary obstructions. It has been made possible to evaluate Myocardial computed tomography perfusion (Myocardial CTP) recently, based on myocardial contrast changes related to coronary stenoses. Several studies have validated this technique against the anatomical reference method (cardiac catheterization) and other functional methods, including myocardial perfusion scintigraphy and fractional flow reserve. The Myocardial CTP is performed in conjunction with the CCTA, a combined analysis of anatomy and function. The stress phase (with assessment of myocardial perfusion) can be performed before or after the resting phase (assessment of resting perfusion and coronary arteries), and different acquisition parameters are proposed according to the protocol and type of equipment used. Stressors used are based on coronary vasodilation (e.g. dipyridamole, adenosine). Image interpretation, similar to other perfusion assessment methods, is based on the identification and quantification of myocardial perfusion defects. The integration of both perfusion and anatomical findings is fundamental for the examination interpretation algorithm, allowing to define if the stenoses identified are hemodynamically significant and may be related to myocardial ischemia.

Evaluation of Myocardial Perfusion by Computed Tomography - Principles, Technical Background and Recommendations / Avaliação da Perfusão Miocárdica por Tomografia Computadorizada - Princípios, Fundamentação Técnica e Recomendações

Abstract Coronary computed tomography angiography (CCTA) has gained a prominent role in the evaluation of coronary artery disease. However, its anatomical nature does not allow the evaluation of the functional repercussion of coronary obstructions. It has been made possible to evaluate Myocardial computed tomography perfusion (Myocardial CTP) recently, based on myocardial contrast changes related to coronary stenoses. Several studies have validated this technique against the anatomical reference method (cardiac catheterization) and other functional methods, including myocardial perfusion scintigraphy and fractional flow reserve. The Myocardial CTP is performed in conjunction with the CCTA, a combined analysis of anatomy and function. The stress phase (with assessment of myocardial perfusion) can be performed before or after the resting phase (assessment of resting perfusion and coronary arteries), and different acquisition parameters are proposed according to the protocol and type of equipment used. Stressors used are based on coronary vasodilation (e.g. dipyridamole, adenosine). Image interpretation, similar to other perfusion assessment methods, is based on the identification and quantification of myocardial perfusion defects. The integration of both perfusion and anatomical findings is fundamental for the examination interpretation algorithm, allowing to define if the stenoses identified are hemodynamically significant and may be related to myocardial ischemia.

Resumo A angiografia coronariana por tomografia computadorizada (ACTC) assumiu um papel de destaque na avaliação da doença arterial coronariana. Entretanto, sua natureza anatômica não permitia a avaliação da repercussão funcional das obstruções coronarianas. Recentemente, tornou-se possível a avaliação da perfusão miocárdica por tomografia computadorizada (PMTC), baseando-se nas alterações de contrastação miocárdicas relacionadas às estenoses coronarianas. Diversos estudos permitiram validar esta técnica perante o método anatômico de referência (cateterismo cardíaco) e outros métodos funcionais, incluindo cintilografia de perfusão miocárdica e a reserva de fluxo fracionada. A PMTC é realizada conjuntamente com a ACTC, em uma análise combinada de anatomia e função. A fase de estresse (com avaliação da perfusão miocárdica) pode ser realizada antes ou depois da fase de repouso (avaliação da perfusão de repouso e artérias coronárias), e diferentes parâmetros de aquisição são propostos conforme o protocolo e o tipo de equipamento utilizados. Os agentes estressores utilizados baseiam-se na vasodilatação coronariana (ex: dipiridamol, adenosina). A interpretação das imagens, semelhante a outros métodos de avaliação perfusional, baseia-se na identificação e quantificação de defeitos de perfusão miocárdicos. A integração dos achados perfusionais e anatômicos é parte fundamental do algoritmo de interpretação do exame, permitindo definir se as estenoses identificadas são hemodinamicamente significativas, podendo se relacionar com isquemia miocárdica.

Desenvolvimento de modelo clínico para predição da possibilidade de identificação da artéria de Adamkiewicz por angiotomografia / Development of a clinical model to predict the likelihood of identification of the Adamkiewicz artery by angiotomography

Contexto: Diferenças morfológicas da artéria de Adamkiewicz (AKA) entre a população portadora e não portadora de doença aórtica têm importância clínica, influenciando as complicações neuroisquêmicas da medula espinhal em procedimentos operatórios. Ainda não é conhecida a correlação entre parâmetros clínicos e a previsibilidade da identificação dessa artéria pela angiotomografia. Objetivo: Desenvolver um modelo matemático que, através de parâmetros clínicos correlacionados com aterosclerose, possa prever a probabilidade de identificação da AKA em pacientes submetidos a angiotomografias. Método: Estudo observacional transversal utilizando banco de imagens e dados de pacientes. Foi feita análise estatística multivariada e criado modelo matemático logit de predição para identificação da AKA. Variáveis significativas foram utilizadas na montagem da fórmula para cálculo da probabilidade de identificação. O modelo foi calibrado, e a discriminação foi avaliada pela curva receiver operating characteristic (ROC). A seleção das variáveis explanatórias foi guiada pela maior área na curva ROC (p = 0,041) e pela significância combinada das variáveis. Resultados: Foram avaliados 110 casos (54,5% do sexo masculino, com idade média de 60,97 anos e etnia com coeficiente B -2,471, M -1,297, N -0,971), com AKA identificada em 60,9%. Índice de massa corporal: 27,06 ± 0,98 (coef. -0,101); fumantes: 55,5% (coef. -1,614/-1,439); diabéticos: 13,6%; hipertensos: 65,5% (coef. -1,469); dislipidêmicos: 58,2%; aneurisma aórtico: 38,2%; dissecção aórtica: 12,7%; e trombo mural: 24,5%. Constante de 6,262. Fórmula para cálculo da probabilidade de detecção: ( ) ( ) . . . . . tan 1 ( 1) Coef Etnia Coef IMC IMC Coef fumante Coef HAS Coe f dislip Cons te e − + ×+ + + + − + . O modelo de predição foi criado e disponibilizado no link https://vascular.pro/aka-model. Conclusão: Com as covariáveis etnia, índice de massa corporal, tabagismo, hipertensão arterial e dislipidemia, foi possível criar um modelo matemático de predição de identificação da AKA com significância combinada de nove coeficientes (p = 0,042)

Background: There are clinically important morphological differences in the Adamkiewicz artery (AKA) between populations that do and do not have aortic disease and they have an influence on the neuroischemic complications involving the spinal cord during surgical operations. It is not yet known whether clinical parameters correlate with the predictability of identification of the artery using angiotomography. Objective: To develop a mathematical model that by correlating clinical parameters with atherosclerosis enables prediction of the probability of identification of the AKA in patients examined with angiotomography. Method: This is a cross-sectional, observational study using a patient database and image bank. A multivariate statistical analysis was conducted and a logit mathematical model was constructed to predict AKA identification. Significant variables were used to build a formula for calculation of the probability of identification. This model was calibrated and its power of discrimination was assessed using receiver operating characteristic (ROC) curves. Selection of explanatory variables was based on largest area under the ROC curve (p = 0.041) and combined significance of variables. Results: A total of 110 cases were analyzed (54.5% were male, mean age was 60.97 years, and ethnicity coefficients were white -2.471, brown -1.297, and black -0.971) and the AKA was identified in 60.9%. Body mass index: 27.06 ± 0.98 (coef. -0.101); smokers: 55.5% (coef. -1.614/-1.439); diabetes: 13.6%; hypertension: 65.5% (coef. -1.469); dyslipidemia: 58.2%; aortic aneurysm: 38.2%; aortic dissection: 12.7%; and mural thrombus: 24.5%. The constant was 6.262. The formula for calculating the probability of detection is as follows: ( ) ( ) . . . ker . . tan 1 ( 1) Coef Etnicity Coef BMI BMI Coef smo Coef SAH Coef dyslip Cons t e − + ×+ + + + − + . The prediction model was constructed and made available at: https://vascular.pro/aka-model. Conclusions: Using the covariates ethnicity, body mass index, smoking, arterial hypertension, and dyslipidemia, it proved possible to create a mathematical model for predicting identification of the AKA with a combined significance of nine coefficients (p = 0.042)

Predictors of Adamkiewicz artery and anterior spinal artery detection through computerized tomographic angiography.

BACKGROUND: The detection of the Adamkiewicz artery and the anterior spinal artery has been associated with the ability to prevent adverse spinal cord outcomes after aortic surgical procedures. Yet, to our knowledge, no previous studies have attempted to use modern predictive models to identify the most important variables in determining artery detectability. AIMS: To develop a model to predict the odds of visualizing the Adamkiewicz artery or anterior spinal artery in patients undergoing computerized tomographic angiography. METHODS: We conducted a prospective, cross-sectional study. Outcomes of interest were the non-detection of the Adamkiewicz artery and anterior spinal artery, and their corresponding level of origin. Axial images were inspected in high definition in search of two dense spots characterizing the Adamkiewicz artery and anterior spinal artery. A multiplanar three-dimensional reconstruction was then performed using the OsiriX® software. RESULTS: A total of 110 participants were part of this analysis. When evaluating risks for the Adamkiewicz artery being undetectable, significant factors could be classified into three broad categories: risk factors for arterial disease, established arterial disease, and obesity. Factors in the former category included metabolic syndrome, hypertension, and smoking status, while factors in the arterial disease included descending aortic aneurysm, mural thrombi, aortic aneurysm without a dissection, and aortic disease in general. In relation to anterior spinal artery not being detectable, significant risk factors included hypertension, smoking status, and metabolic syndrome, while those associated with arterial disease involved aortic disease and arterial thrombi. When evaluating the importance of individual clinical factors, the presence of higher body mass index was the single most important risk factor. CONCLUSION: Arterial disease, established arterial disease, and increased body mass index are risk factors in the detection of Adamkiewicz artery and anterior spinal artery. Specific diagnostic protocols should be in place for patients with these underlying conditions, thus enhancing the likelihood of detection when the Adamkiewicz artery is indeed present.

Decreased glycolytic metabolism in non-compaction cardiomyopathy by 18F-fluoro-2-deoxyglucose positron emission tomography: new insights into pathophysiological mechanisms and clinical implications.

AIMS: The pathophysiological mechanisms of left ventricular non-compaction cardiomyopathy (LVNC) remain controversial. This study performed combined 18F-fluoro-2-deoxyglucose dynamic positron emission tomography (FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (SPECT) studies to evaluate myocardial glucose metabolism and perfusion in patients with LVNC and their clinical implications. METHODS AND RESULTS: Thirty patients (41 ± 12 years, 53% male) with LVNC, diagnosed by cardiovascular magnetic resonance (CMR) criteria, and eight age-matched healthy controls (42 ± 12 years, 50% male) were prospectively recruited to undergo FDG-PET with measurement of the myocardial glucose uptake rate (MGU) and SPECT to investigate perfusion-metabolism patterns. Patients with LVNC had lower global MGU compared with that in controls (36.9 ± 8.8 vs. 44.6 ± 5.4 µmol/min/100 g, respectively, P = 0.02). Of 17 LV segments, MGU levels were significantly reduced in 8, and also a reduction was observed when compacted segments from LVNC were compared with the segments from control subjects (P < 0.001). Perfusion defects were also found in 15 (50%) patients (45 LV segments: 64.4% match, and 35.6% mismatch perfusion-metabolism pattern). Univariate and multivariate analyses showed that beta-blocker therapy was associated with increased MGU (beta coefficient = 10.1, P = 0.008). Moreover, a gradual increase occurred in MGU across the beta-blocker dose groups (P for trend = 0.01). CONCLUSION: The reduction of MGU documented by FDG-PET in LVNC supports the hypothesis that a cellular metabolic pathway may play a role in the pathophysiology of LVNC. The beneficial effect of beta-blocker mediating myocardial metabolism in the clinical course of LVNC requires further investigation.

Noncompaction cardiomyopathy: a substrate for a thromboembolic event.

BACKGROUND: Noncompaction cardiomyopathy (NCC) is a rare genetic cardiomyopathy characterized by a thin, compacted epicardial layer and an extensive noncompacted endocardial layer. The clinical manifestations of this disease include ventricular arrhythmia, heart failure, and systemic thromboembolism. CASE PRESENTATION: A 43-year-old male was anticoagulated by pulmonary thromboembolism for 1 year when he developed progressive dyspnea. Cardiovascular magnetic resonance imaging showed severe biventricular trabeculation with an ejection fraction of 15%, ratio of maximum noncompacted/compacted diastolic myocardial thickness of 3.2 and the presence of exuberant biventricular apical thrombus. CONCLUSION: Still under discussion is the issue of which patients and when they should be anticoagulated. It is generally recommended to those presenting ventricular systolic dysfunction, antecedent of systemic embolism, presence of cardiac thrombus and atrial fibrillation. In clinical practice the patients with NCC and ventricular dysfunction have been given oral anticoagulation, although there are no clinical trials showing the real safety and benefit of this treatment.

Myocardial fibrosis detected by cardiac CT predicts ventricular fibrillation/ventricular tachycardia events in patients with hypertrophic cardiomyopathy.

BACKGROUND: Myocardial fibrosis (MF) occurs in up to 80% of subjects with asymptomatic or mildly symptomatic hypertrophic cardiomyopathy (HCM) and can constitute an arrhythmogenic substrate for re-entrant, life-threatening ventricular arrhythmias in predisposed persons. OBJECTIVE: The aim was to investigate whether MF detected by delayed enhancement cardiac CT is predictive of ventricular tachycardia (VT) and fibrillation (VF) that require appropriate therapy by an implantable cardioverter defibrillator (ICD) in patients with HCM. METHODS: Twenty-six patients with HCM with previously (for at least 1 year) implanted ICD underwent MF evaluation by cardiac CT. MF was quantified by myocardial delayed enhanced cardiac CT. Data on ICD firing were recorded every 3 months after ICD implantation. Risk factors for sudden cardiac death in patients with HCM were evaluated in all patients. RESULTS: MF was present in 25 of 26 patients (96%) with mean fibrosis mass of 20.5 ± 15.8 g. Patients with appropriate ICD shocks for VF/VT had significantly greater MF mass than patients without (29.10 ± 19.13 g vs 13.57 ± 8.31 g; P = .01). For a MF mass of at least 18 g, sensitivity and specificity for appropriate ICD firing were 73% (95% CI, 49%-88%) and 71% (95% CI, 56%-81%), respectively. Kaplan-Meier curves indicated a significantly greater VF/VT event rate in patients with MF mass ≥18 g than in patients with MF <18 g (P = .02). In the Cox regression analysis, the amount of MF was independently associated with VF/VT in ICD-stored electrograms. CONCLUSION: The mass of MF detected by cardiac CT in patients with HCM at high risk of sudden death was associated with appropriate ICD firings.

Dynamic myocardial perfusion imaging by dual-source computed tomography.

We report a dual-source computed tomography study of dynamic and quantitative myocardial perfusion in a 44-year-old patient with previous documented coronary artery disease. Quantitatively, the tomography showed myocardial perfusion deficit in the territories with significant coronary stenosis, confirmed by computed tomography angiography and conventional angiography. Dual-source computed tomography allowed dynamic perfusion and anatomic evaluation in a single study during the follow-up of this patient.

Perfusão miocárdica dinâmica por tomografia computadorizada de dupla fonte de raio X / Dynamic myocardial perfusion imaging by dual-source computed tomography / Perfusión miocárdica dinámica por tomografía computarizada de doble fuente de rayos X

Relatamos caso de perfusão dinâmica e quantitativa pela tomografia computadorizada de múltiplos detectores de dupla fonte de Raio X em um paciente de 44 anos, com diagnóstico prévio de doença coronariana. A tomografia demonstrou quantitativamente déficit de perfusão miocárdica nos territórios irrigados por artérias com estenoses significativas confirmadas pela angiotomografia e pela cineangiocoronariografia. A tomografia computadorizada com dupla fonte de Raio X permitiu a avaliação dinâmica perfusional e anatômica, em um único estudo, durante o controle evolutivo desse paciente.

We report a dual-source computed tomography study of dynamic and quantitative myocardial perfusion in a 44-year-old patient with previous documented coronary artery disease. Quantitatively, the tomography showed myocardial perfusion deficit in the territories with significant coronary stenosis, confirmed by computed tomography angiography and conventional angiography. Dual-source computed tomography allowed dynamic perfusion and anatomic evaluation in a single study during the follow-up of this patient.

Relatamos un caso de perfusión dinámica y cuantitativa por la tomografía computarizada de múltiples detectores de doble fuente de Rayos X, en un paciente de 44 años, con diagnóstico previo de enfermedad coronaria. La tomografía demostró cuantitativamente, un déficit de perfusión miocárdica en los territorios irrigados por arterias con estenosis significativas confirmadas por la angiotomografía y por la cineangiocoronariografía. La tomografía computarizada con doble fuente de Rayos X, permitió la evaluación dinámica de la perfusión y de la anatomía en un único estudio y durante el control evolutivo de ese paciente.

Contribuição da ressonância magnética na investigação da doença arterial coronária / Role of magnetic resonance imaging in the evaluation of coronary artery disease

A ressonância magnética (RM) é um método que recentemente foi introduzido no arsenal diagnóstico em cardiologia. O estudo por RM permite a avaliação da anatomia, da função global e regional, além da perfusão e viabilidade miocárdicas. Várias técnicas estão disponíveis como: 1) a cine ressonância, 2) a perfusão miocárdica de primeira passagem de contraste (gadolínio), 3) o realce tardio e 4) a detecção de edema secundário ao infarto em quadros agudos. Vários autores descrevem o método como padrão ouro para a avaliação da função ventricular, em especial em corações com alterações geométricas, frequentemente encontradas na DAC. A investigação de isquemia miocárdica se faz pela análise qualitativa ou quantitativa do transito do gadolínio pelo miocárdio do ventrículo esquerdo (primeira passagem), durante o estímulo farmacológico com dipiridamol / adenosina ou da alteração da contratilidade induzida após a infusão de dobutamina. A técnica de realce tardio permite a avaliação da viabilidade miocárdica, com importantes informações clínicas como 1) a definição de infartos agudos ou crônicos; 2)áreas de risco, porém viáveis; 3) isquemia reversível mesmo com o miocárdio atordoado; 4) extensão do miocárdio disfuncionante e sua recuperação funcional após a revascularização (realce acometendo menos que 25 por cento da parede recuperam função enquanto segmentos com realce acima de 75 por cento da parede tem baixa probabilidade de recuperação).