On the search of arterial geometry heritability.

BACKGROUND: Geometrical risk factors for CAD have been previously proposed before. To date, however, the effect of those factors is not conclusive, and remains as an open research field. Here, we hypothesize that some of these factors have a genetic component explaining inter-individual variability. OBJECTIVE: To detect heritability indicators of the coronary arterial geometry. MATERIALS AND METHODS: A patient sample of 48 individuals, consisting of 24 siblings, was used. Three dimensional geometry of the LAD, LCx and RCA were reconstructed from standard CCTA. Arterial models were characterized in terms of 20+ geometric descriptors (phenotypes). A comprehensive statistical analysis to detect potential heritability of such phenotypes was employed. Heritability was assessed by means of several statistical indexes. Finally, the association of phenotypes to stenotic lesion is also reported. RESULTS: The RCA scored positive indications for heritability in 15+ phenotypes, while the LAD in 10 and the LCx in only 3 phenotypes. Association between presence of lesion and phenotypes was higher in the LAD, 10+ phenotypes, while for the LCx only 2 phenotypes were significantly associated, and none association was found for the RCA. CONCLUSION: The RCA showed potential heritability for the largest number of phenotypes, followed by the LAD. The LCx presents the weaker association of morphology among siblings. Regarding lesion-geometry associations, the there are hints of an underlying relation in the LAD, the LCx featured a weaker association and the RCA showed none. This difference could be related to the different hemodynamic environments in these arteries.

Late gadolinium enhancement magnetic resonance imaging in the diagnosis and prognosis of endomyocardial fibrosis patients.

BACKGROUND: Endocardial fibrous tissue (FT) deposition is a hallmark of endomyocardial fibrosis (EMF). Echocardiography is a first-line and the standard technique for the diagnosis of this disease. Although late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) allows FT characterization, its role in the diagnosis and prognosis of EMF has not been investigated. METHODS AND RESULTS: Thirty-six patients (29 women; age, 54±12 years) with EMF diagnosis after clinical evaluation and comprehensive 2-dimensional Doppler echocardiography underwent cine-CMR for assessing ventricular volumes, ejection fraction and mass, and LGE-CMR for FT characterization and quantification. Indexed FT volume (FT/body surface area) was calculated after planimetry of the 8 to 12 slices obtained in the short-axis view at end-diastole (mL/m(2)). Surgical resection of FT was performed in 16 patients. In all patients, areas of LGE were confined to the endocardium, frequently as a continuous streak from the inflow tract extending to the apex, where it was usually most prominent. There was a relation between increased FT/body surface area and worse New York Heart Association functional class and with increased probability of surgery (P<0.05). The histopathologic examination of resected FT showed typical features of EMF with extensive endocardial fibrous thickening, proliferation of small vessels, and scarce inflammatory infiltrate. In multivariate analysis, the patients with FT/body surface area >19 mL/m(2) had an increased mortality rate, with a relative risk of 10.8. CONCLUSIONS: Our study provides evidence that LGE-CMR is useful in the diagnosis and prognosis of EMF through quantification of the typical pattern of FT deposition.

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).

[Coronary calcium score as predictor of stenosis and events in pretransplant renal chronic failure].

BACKGROUND: Coronary artery disease (CAD) is the major cause of death among chronic renal failure (CRF) patients. Traditional, non-invasive exams to detect CAD and to predict events have shown insufficient results in this group. CT Scan evaluation of Coronary Calcium Score (CCS) has proven to be of prognostic value for the population reporting no renal condition. OBJECTIVE: To investigate CCS accuracy in detecting obstructive CAD and in predicting cardiovascular events in candidates to renal transplant as compared to quantitative invasive coronary angiography (ICA). METHODS: Ninety-seven (97) CRF patients aged > or =35 were evaluated. Obstructive CAD was considered as > or =50% or > or =70% stenosis on ICA. Descriptive data, concordance, diagnostic tests, Kaplan-Meier, and multivariate analysis were used. RESULTS: Agatston mean score was 580.6 +/- 1,102.2. Minimum and maximum values were 0 and 7,994, with median at 176. Only 14 patients had zero calcium score. No differences were reported in regard to ethnicity. Highest regional calcium was associated to the highest probability of coronary stenosis in the same segment. Agatston calcium score showed high accuracy for the diagnosis of > or =50% and > or =70% stenosis, with area under ROC curve (AUC) of 0.75 and 0.70, respectively. At the threshold of 400, calcium score identified a subgroup with a higher rate of cardiovascular events at an average follow-up time of 29+/-11.0 months. CONCLUSION: CCS proved to have good diagnostic and prognostic performance for cardiovascular events evaluation in CRF patients.

Escore de cálcio coronariano prediz estenose e eventos na insuficiência renal crônica pré-transplante / Score de calcio coronario predice estenosis y eventos en la insuficiencia renal crónica pre trasplante / Coronary calcium score as predictor of stenosis and events in pretransplant renal chronic failure

FUNDAMENTO: A doença arterial coronariana (DAC) é a principal causa de óbito em pacientes com insuficiência renal crônica (IRC). Os exames não invasivos tradicionais para detecção de DAC e predição de eventos têm apresentado resultados insuficientes nesse grupo. A avaliação do escore de cálcio coronariano (ECC) por tomografia computadorizada tem comprovado valor prognóstico na população sem doença renal. OBJETIVO: Avaliar a acurácia do ECC para detectar DAC obstrutiva e prever eventos cardiovasculares em candidatos a transplante renal comparada à angiografia coronariana invasiva (ACI) quantitativa. MÉTODOS: Foram avaliados 97 pacientes com IRC e idade > 35anos. Foi considerada DAC obstrutiva a presença de estenose >50 por cento ou >70 por cento pela ACI. Dados descritivos, concordância, testes diagnósticos, Kaplan-Meier e análise multivariada foram utilizados. RESULTADOS: O escore de Agatston médio foi de 580,6 ± 1.102,2; os valores mínimos e máximos foram 0 e 7.994, e mediana de 176. Apenas 14 pacientes tinham escore de cálcio de zero. Não houve diferenças entre as etnias e a maior presença de cálcio regional associou-se a maior probabilidade de estenose coronária no mesmo segmento. O escore de cálcio de Agatston apresentou boa acurácia para o diagnóstico de estenose, >50 por cento e >70 por cento com área sob a curva ROC de 0,75 e 0,70, respectivamente. No limiar de 400, o escore de cálcio identificou o subgrupo com maior taxa de eventos cardiovasculares em tempo médio de seguimento de 29,1±11,0 meses. CONCLUSÃO: O ECC na avaliação de DAC apresentou boa performance diagnóstica e prognóstica para eventos cardiovasculares em pacientes com insuficiência renal crônica (IRC).

BACKGROUND: Coronary artery disease (CAD) is the major cause of death among chronic renal failure (CRF) patients. Traditional, non-invasive exams to detect CAD and to predict events have shown insufficient results in this group. CT Scan evaluation of Coronary Calcium Score (CCS) has proven to be of prognostic value for the population reporting no renal condition. OBJECTIVE: To investigate CCS accuracy in detecting obstructive CAD and in predicting cardiovascular events in candidates to renal transplant as compared to quantitative invasive coronary angiography (ICA). METHODS: Ninety-seven (97) CRF patients aged > 35 were evaluated. Obstructive CAD was considered as >50 percent or >70 percent stenosis on ICA. Descriptive data, concordance, diagnostic tests, Kaplan-Meier, and multivariate analysis were used. RESULTS: Agatston mean score was 580.6 ± 1,102.2. Minimum and maximum values were 0 and 7,994, with median at 176. Only 14 patients had zero calcium score. No differences were reported in regard to ethnicity. Highest regional calcium was associated to the highest probability of coronary stenosis in the same segment. Agatston calcium score showed high accuracy for the diagnosis of >50 percent and >70 percent stenosis, with area under ROC curve (AUC) of 0.75 and 0.70, respectively. At the threshold of 400, calcium score identified a subgroup with a higher rate of cardiovascular events at an average follow-up time of 29±11.0 months. CONCLUSION: CCS proved to have good diagnostic and prognostic performance for cardiovascular events evaluation in CRF patients.

FUNDAMENTO: La enfermedad arterial coronaria (EAC) es la principal causa de óbito en pacientes con insuficiencia renal crónica (IRC). Los exámenes no invasivos tradicionales para detección de EAC y predicción de eventos vienen presentando resultados insuficientes en este grupo. La evaluación del score de calcio coronario (SCC) por tomografía computarizada ha estado comprobando valor pronóstico en la población sin enfermedad renal. OBJETIVO: Evaluar la exactitud del SCC para detectar EAC obstructiva y prever eventos cardiovasculares en candidatos a trasplante renal comparada a la angiografía coronaria invasiva (ACI) cuantitativa. MÉTODOS: Se evaluaron a 97 pacientes con IRC y edad > 35 años. Se consideró como EAC obstructiva la presencia de estenosis > 50 por ciento o > 70 por ciento por la ACI. Datos descriptivos, concordancia, pruebas diagnósticas, Kaplan-Meier y análisis multivariado se utilizaron. RESULTADOS: El score de Agatston promedio fue de 580,6 ± 1.102,2; los valores mínimos y máximos fueron 0 y 7.994, y mediana de 176. Solamente 14 pacientes tenían score de calcio de cero. No hubo diferencias entre las etnias y la mayor presencia de calcio regional se asoció a la mayor probabilidad de estenosis coronaria en el mismo segmento. El score de calcio de Agatston presentó buena exactitud para el diagnóstico de estenosis, > 50 por ciento y > 70 por ciento con área bajo la curva ROC de 0,75 y 0,70, respectivamente. En el umbral de 400, el score de calcio identificó el subgrupo con mayor tasa de eventos cardiovasculares en tiempo promedio de seguimiento de 29,1 ± 11,0 meses. CONCLUSIÓN: El SCC en la evaluación de EAC presentó una buena performance diagnóstica y pronostica para eventos cardiovasculares en pacientes con insuficiencia renal crónica (IRC).

Relation between visceral fat and coronary artery disease evaluated by multidetector computed tomography.

Visceral abdominal fat has been associated to cardiovascular risk factors and coronary artery disease (CAD). Computed tomography (CT) coronary angiography is an emerging technology allowing detection of both obstructive and nonobstructive CAD adding information to clinical risk stratification. The aim of this study was to evaluate the association between CAD and adiposity measurements assessed clinically and by CT. We prospectively evaluated 125 consecutive subjects (57% men, age 56.0+/-12 years) referred to perform CT angiography. Clinical and laboratory variables were determined and CT angiography and abdominal CT were performed in a 64-slice scanner. CAD was defined as any plaque calcified or not detected by CT angiography. Visceral and subcutaneous adiposity areas were determined at different intervertebral levels. CT angiography detected CAD in 70 (56%) subjects, and no association was found with usual anthropometric adiposity measurements (waist and hip circumferences and body mass index). Otherwise, CT visceral fat areas (VFA) were significantly related to CAD. VFA T12-L1 values > or =145cm(2) had an odds ratio of 2.85 (95% CI 1.30-6.26) and VFA L4-L5 > or =150cm(2) had a 2.87-fold (95% CI 1.31-6.30) CAD risk. The multivariate analysis determined age and VFA T12-L1 as the only independent variables associated to CAD. Visceral fat assessed by CT is an independent marker of CAD determined by CT angiography.

Contrast-enhanced magnetic resonance imaging identifies focal regions of intramyocardial fibrosis in patients with severe aortic valve disease: Correlation with quantitative histopathology.

BACKGROUND: Chronic aortic valve disease (AVD) is characterized by progressive accumulation of interstitial myocardial fibrosis (MF). However, assessment of MF accumulation has only been possible through histologic analyses of endomyocardial biopsies. We sought to evaluate contrast-enhanced magnetic resonance imaging (ce-MRI) as a noninvasive method to identify the presence of increased MF in patients with severe AVD. METHODS: Seventy patients scheduled to undergo aortic valve replacement surgery were examined by cine and ce-MRI in a 1.5-T scanner. Cine images were used for the assessment of left ventricular (LV) volumes, mass, and function. Delayed-enhancement images were used to characterize the regions of MF. In addition, histologic analyses of myocardial samples obtained during aortic valve replacement surgery were used for direct quantification of interstitial MF. Ten additional subjects who died of noncardiac causes served as controls for the quantitative histologic analyses. RESULTS: Interstitial MF determined by histopathologic analysis was higher in patients with AVD than in controls (2.7% +/- 2.0% vs 0.6% +/- 0.2%, P = .001). When compared with histopathologic results, ce-MRI demonstrated a sensitivity of 74%, a specificity of 81%, and an accuracy of 76% to identify AVD patients with increased interstitial MF. There was a significant inverse correlation between interstitial MF and LV ejection fraction (r = -0.67, P < .0001). Accordingly, patients with identifiable focal regions of MF by ce-MRI exhibited worse LV systolic function than those without MF (45% +/- 14% vs 65% +/- 14%, P < .0001). CONCLUSIONS: Contrast-enhanced MRI allows for the noninvasive detection of focal regions of MF in patients with severe AVD. Moreover, patients with identifiable MF by ce-MRI exhibited worse LV functional parameters.

CT angiography in highly calcified arteries: 2D manual vs. modified automated 3D approach to identify coronary stenoses.

BACKGROUND: Two-dimensional axial and manually-oriented reformatted images are traditionally used to analyze coronary data provided by multidetector-row computed tomography angiography (MDCTA). While apparently more accurate in evaluating calcified vessels, 2D methods are time-consuming compared with automated 3D approaches. The purpose of this study was to evaluate the performance of a modified automated 3D approach (using manual vessel isolation and different window and level settings) in a population with high calcium scores who underwent coronary half-millimeter 16-detector-row CT angiography (16 x 0.5-MDCTA). METHODS: ECG-gated 16 x 0.5-MDCTA (16 x 0.5 mm cross-sections, 0.35 x 0.35 x 0.35 mm3 isotropic voxels, 400 ms rotation) was performed after injection of iopamidol (120-ml, 300 mg/ml) in 19 consecutive patients (11 male, 62+/-10 years-old). Native arteries were independently evaluated for >or=50%-stenoses using both manual 2D and modified automated 3D approaches. Stents and bypass grafts were excluded. Conventional coronary angiography was visually analyzed by 2 observers. RESULTS: Median Agatston calcium score was 434. Sensitivities, specificities, positive and negative predictive values for detection of >or=50% coronary stenoses using the 2D and modified 3D approaches were, respectively: 74%/63%, 76%/80%, 45%/34%, and 91%/93% (p=NS for all comparisons). Overall diagnostic accuracies were 75 and 78%, respectively (p=NS). Uninterpretable vessels were, respectively: 37% (77/209) and 35% (73/209) - p=NS. Time to analyze a single study was 160+/-23 and 53+/-11 min, respectively (p<0.01). CONCLUSIONS: This modified automated 3D approach is equivalent to and significantly less time consuming than the traditional manual 2D method for evaluation of >or=50%-stenoses by 16 x 0.5-MDCTA in native coronary arteries of patients with high calcium scores.

Myocardial delayed enhancement by magnetic resonance imaging in patients with Chagas' disease: a marker of disease severity.

OBJECTIVES: We sought to investigate whether myocardial delayed enhancement (MDE) by magnetic resonance imaging (MRI) could quantify myocardial fibrosis (MF) in patients with Chagas' heart disease (CHD), thus defining the severity of the disease. BACKGROUND: Myocardial fibrosis secondary to ischemic disease can be imaged using MDE. Advanced CHD is characterized by progressive MF. METHODS: Fifty-one patients with CHD were enrolled: 15 seropositive asymptomatic participants in the indeterminate phase (IND); 26 patients with known clinical CHD; and 10 patients with known CHD and ventricular tachycardia (VT). Using a 1.5-T MRI system, we acquired left ventricular (LV) short-axis slices using cine-MRI (LV function) and inversion-recovery gradient-echo (MDE). RESULTS: Myocardial fibrosis by MRI was present in 68.6% of all patients, in 20% of IND, 84.6% of CHD, and 100% of VT (p < 0.001). Quantified MF increased progressively across disease severity subgroups (0.9 +/- 2.3% in IND; 16.0 +/- 12.3% in CHD; and 25.4 +/- 9.8% in VT, p < 0.001) and New York Heart Association functional classes (I: 7.5 +/- 9.5%; II: 21.9 +/- 13.8%; and III: 25.3 +/- 9.9% of LV mass, p < 0.001). Left ventricular ejection fraction and MF had significant negative correlation (r = -0.78, p < 0.001), similar to the segmental MF and function: 4.9 +/- 15.1% of MF in normal function, 32.5 +/- 32.5% in mildly hypokinetic, 57.8 +/- 31.4% in severely hypokinetic, and 72.3 +/- 36.2% in akinetic and dyskinetic segments, respectively (p < 0.001). CONCLUSIONS: In CHD, MDE by MRI quantifies MF that not only can be detected in the early asymptomatic stages but parallels well-established prognostic factors and provides unique information for clinical disease staging.

Perfusäo cerebral retrógrada é método eficaz de proteçäo cerebral?: resultados imediatos de estudo consecutivo e randomizado / Is retrograde cerebral perfusion an effective method for cerebral protection?: immediate results of a consecutive and randomized study

Foram estudados 30 pacientes com diagnóstico de aneurisma ou dissecçäo de aorta tratados cirurgicamente. O método utilizado consistiu: uso de hipotermia profunda, parada circulatória total, infusäo de 0,20 mg/Kg de peso de dexametasona intravenosa e 10 mg/Kg/peso de thiopental, colocaçäo dos pacientes em Trendelemburg a 45 graus durante o período de parada respiratória. Os 30 pacientes foram operados consecutivamente e randomizados em 2 grupos. Grupo I constituído de 15 pacientes, nos quais foi utilizada a perfusäo cerebral retrógrada (PCR) através da veia cava superior e Grupo II também com 15 pacientes nos quais näo foi utilizada PCR. Onze (36,7 por cento) pacientes tinham aneurisma da aorta ascendente e arco aórtico, 7 (23,3 por cento) tinham dissecçäo aguda da aorta do tipo I, 6 (20 por cento) com dissecçäo crônica da aorta ascendente e os 6 (20 por cento) restantes outros diagnósticos näo agrupáveis. Foi realizada análise das seguintes variáveis independentes para mortalidade: idade, sexo, tempo de circulaçäo extracorpórea, tempo de parada circulatória, diagnóstico, complicaçöes prévias, comparando os dois grupos. A mortalidade imediata do Grupo I foi de 4/15 (insuficiência respiratória) 26,6 por cento e no Grupo II 3/15 (coma) 20,0 por cento - p =1,00. A incidência de complicaçöes neurológicas no Grupo I foi 3/15 (20,0 por cento) e no Grupo II, 2/15 (13,3 por cento) p = 1,000. A análise estatística utilizando o teste exato de Fisher näo demonstrou diferença entre os dois grupos com relaçäo à mortalidade imediata e complicaçöes neurológicas. As causas de óbito foram: insuficiência respiratória em 4 pacientes, alteraçäo neurológica, hiperpotassemia e infarto do miocárdio, respectivamente nos 3 últimos. No presente trabalho, concluímos que a associaçäo de PCR näo oferece proteçäo cerebral mais eficaz que a parada circulatória total associada à hipotermia profunda, para o tempo de isquemia utilizado.