Aterosclerose carotídea avaliada pelo eco-Doppler: associação com fatores de risco e doenças arteriais sistêmicas

Indications for carotid Doppler ultrasound in asymptomatic patients - are we ordering it correctly?

Background

Carotid arteries are frequently the site of pathologies, the most common being atherosclerosis, which may result in the formation of plaques, causing stenosis. Doppler ultrasound is currently the exam of choice for assessment of the carotid arteries in asymptomatic patients to screen for and diagnose vascular lesions. Current guidelines recommend screening patients who have risk factors for carotid stenosis and who are able and willing to undergo medical treatment and/or carotid intervention. Screening asymptomatic patients in the general adult population who have no significant risk factors is not recommended.

Objectives

To assess whether medical experts rely on the literature to request Doppler ultrasound for screening.

Methods

A retrospective selection of patients was performed based on requests for carotid ultrasound. The data collected were computed and analyzed using RStudio version 1.3.959.

Results

The request was evaluated as appropriate as long as the patients presented at least one risk factor for carotid plaques. Fifty-five out of 152 patients met criteria for carotid screening. The most frequent indication in the study population was vascular check-up. Arterial hypertension was the most prevalent risk factor. Vascular surgery specialists were more likely to order the exam correctly (odds ratio for correct indications: 3.52 [CI 1.14 - 10.87], with p=0.02). The rate of correct Doppler ultrasound requests was 36% (95%CI 29 to 42%).

Conclusions

An excess of requests for carotid ultrasound screening was found in this study. Vascular surgeons more often requested the test correctly.

Comparação das artérias carótidas comuns de equinos e muares por ultrassonografia modo-B e Doppler espectral e a relação com a massa corpórea

RESUMO A ultrassonografia convencional e o Doppler espectral nas artérias carótidas comuns em equinos e muares são considerados escassos, diferentemente do que ocorre na medicina humana. Este trabalho propôs comparar as artérias carótidas comuns de equinos e muares por ultrassonografia modo-B e Doppler espectral, além de verificar as diferenças dessas variáveis entre os gêneros desses animais e a relação com a massa corpórea. Foram avaliados os seguintes parâmetros: massa corpórea, diâmetros das artérias, espessura da camada íntima-média (EIM), índice de resistividade (IR), índice de pulsatilidade (IP), velocidade sistólica (VS), velocidade diastólica (VD) e velocidade média (VM). Salvo a massa corpórea, esses parâmetros foram obtidos de três regiões (cranial, médio e caudal) e submetidos à análise conjuntamente. Os diâmetros das artérias carótidas comuns são diferentes entre equinos e muares, com valores menores nos equinos. O IR, o IP, a VS e a VM diferiram entre equinos e muares, sendo maiores nos equinos, e a VD superior nos muares. Não foi observada diferença das variáveis do modo-B e Doppler entre gêneros nos equinos, diferentemente dos muares, cujos machos apresentaram valores maiores do diâmetro, do IR e do IP, mas menores da VS e da VM. A massa corpórea não influenciou as variáveis do modo-B, independentemente do gênero, mas apresenta correlação significativa nas variáveis do modo Doppler. As artérias carótidas comuns de equinos e muares são diferentes pelos exames ultrassonográficos modo-B e Doppler espectral. O gênero não influencia no modo-B e no Doppler nos equinos, porém influencia parcialmente nos muares. A massa corpórea de equinos e de muares, independentemente do gênero, não tem associação com as variáveis do modo-B, apenas com o Doppler.

Prevalence and risk factors of asymptomatic carotid artery stenosis in Indian population: An 8-year follow-up study

BACKGROUND

Asymptomatic carotid artery stenosis (ACAS) is a marker for cerebrovascular disease, coronary atherosclerosis, and death.

AIM

To investigate the prevalence of ACAS in the Indian population, and to correlate ACAS with other vascular risk factors.

MATERIALS AND METHODS

We prospectively recruited 1500 individuals who were older than 40 years and asymptomatic for cerebrovascular disease between June 2003 and December 2014. Evaluation of vascular risk factors was done for all the participants. Color Doppler of bilateral carotid arteries was performed for all the participants. Carotid stenosis of 1-49% and ≥50% was considered to be mild and significant stenosis, respectively.

RESULTS

There were 1016 (67.7%) men, with a mean age of 58.1 ± 10.6 years (age range: 40-98 years). The prevalence of significant carotid stenosis was 5.2%. After adjustment using multiple regression analysis, age >70 years (OR: 2.0; 95% CI: 1.48-2.74), hypertension (OR: 1.8; 95% CI: 1.11-2.96), diabetes (OR: 2.3; 95%CI: 1.45-3.89), smoking (OR: 3.6; 95% CI: 2.18-6.03), dyslipidemia (OR: 4.0; 95% CI: 2.52-6.63), history of migraine (OR: 3.6; 95% CI: 2.54-9.13), history of periodontitis (OR: 3.2; 95% CI: 1.90-5.68), and family history of stroke (OR: 7.1; 95% CI: 4.20-12.2) were significantly associated with >50% stenosis. Duration (>15 years) of hypertension (OR: 2.5; 95% CI: 1.33-6.43), diabetes (OR: 6.2; 95% CI: 3.41-11.3), and smoking (OR: 5.2; 95% CI: 2.20-12.1) markedly worsened the risk. During the 8-year follow up, 14 participants (1.4%) with mild stenosis and 3 participants (4.7%) with significant stenosis developed stroke.

CONCLUSIONS

Our study suggests that 5.2% of asymptomatic individuals > 40 years of age harbor significant extracranial carotid artery disease. Presence of multiple vascular risk factors markedly increases the risk of carotid stenosis.

Variation of Carotid Intima Media Thickness With Body Mass Index in Healthy Adults of Black African Descent

OBJECTIVES

Studies have shown that common carotid intima media thickness (CIMT) measured by B-mode sonography increases with body mass index (BMI) among subjects with cardiovascular diseases in different populations. However, association of body fat and subclinical atherosclerosis in the absence of these cardiovascular diseases is understudied. We aimed to evaluate the correlation between BMI and CIMT in a healthy adult population of black African ancestry.

METHODS

This is a cross-sectional prospective study in 300 consecutive apparently healthy subjects aged 18 to 70 years without history of hypertension, dyslipidemia, diabetes mellitus, and renal disease. Subjects' common carotid artery intima media thickness was measured with a 7.5-MHz linear ultrasound transducer at a point 10 mm proximal to the carotid bulb. All subjects' biodata, medical history, anthropometric (weight and height from which BMI was calculated), laboratory (fasting lipid profile and blood glucose), and CIMT values were recorded on a pro forma. Data were analysed using SPSS version 21, and significant P was set at less than .05.

RESULTS

The right, left, and average CIMT of both sides in our study subjects are 0.52 ± 0.11 mm, 0.51 ± 0.11 mm and 0.52 ± 0.11 mm respectively, with no significant difference between the right and left sides (P > .05). The right, left, and average CIMT increased with increasing age and BMI category (all P < .01) but were not significantly different between men and women (all P > .05). Age (r = .824, .825, and .827; P < .01) and BMI (r = .503, .504, .507; P < .01) had strong positive correlations with right, left, and average CIMT.

CONCLUSIONS

Increasing age and BMI category, but not sex, significantly influenced CIMT values in our apparently healthy black African population.

Can common carotid intima media thickness serve as an indicator of both cardiovascular phenotype and risk among black Africans?

BACKGROUND

It is not known whether common carotid intima media thickness (CIMT) can serve as a surrogate marker of cardiovascular risk among black Africans. Therefore, we examined whether CIMT differed significantly among individuals with distinct cardiovascular phenotype and correlated significantly with traditional cardiovascular risk factors in a black African population.

METHODS

CIMT was measured in 456 subjects with three distinct cardiovascular phenotypes - 175 consecutive Nigerian African stroke patients, 161 hypertensive patients without stroke and 120 normotensive non-smoking adults. For each pair of cardiovascular phenotypes, c-statistics were obtained for CIMT and traditional vascular risk factors (including age, gender, weight, waist circumference, smoking, alcohol, systolic and diastolic blood pressures, fasting plasma glucose, fasting total cholesterol). Pearson's correlation coefficients were calculated to quantify bivariate relationships.

FINDINGS

Bilaterally, CIMT was significantly different among the three cardiovascular phenotypes (right: p < 0.001, F = 33.8; left: p < 0.001, F = 48.6). CIMT had a higher c-statistic for differentiating stroke versus normotension (c = 0.78 right; 0.82 left, p < 0.001) and hypertension versus normotension (c = 0.65 right; 0.71 left, p < 0.001) than several traditional vascular risk factors. Bilaterally, combining all subjects, CIMT was the only factor that correlated significantly (right: 0.12 ≤ r ≤ 0.41, 0.018 ≤ p < 0.0001; left: 0.18 ≤ r ≤ 0.41, 0.005 ≤ p < 0.0001) to all the traditional cardiovascular risk factors assessed.

CONCLUSION

Our findings support CIMT as a significant indicator of both cardiovascular risk and phenotype among adult black Africans. However, specific thresholds need to be defined based on prospective studies.

Mapeamento ecográfico da bifurcação das artérias carótidas extracranianas para planejamento cirúrgico: diferenças baseadas no gênero do paciente

CONTEXTO: A ecografia das artérias carótidas extracranianas já se estabeleceu como método diagnóstico de imagem pré-operatória, e para seguimento de pacientes. OBJETIVO: Avaliar diferenças do mapeamento ecográfico em função do gênero masculino ou feminino dos pacientes. MÉTODOS: Ultrassonografia de alta resolução foi realizada antes do tratamento cirúrgico de 500 bifurcações carotídeas em 192 mulheres e 308 homens. Análise de diferenças baseadas no gênero foi feita em imagens modo B e fluxo a cor, transversal e longitudinal, e medidas duplex doppler de velocidades. Porcentual de estenose expressa em redução de diâmetro, comprimento de placa, diâmetros das artérias carótida interna distal e comum, e distância da bifurcação ao lóbulo da orelha foram comparados. Média, desvio padrão, mínimo e máximo foram descritos. Comparações estatísticas foram baseadas em testes t de Student e do Χ2. RESULTADOS: Estenoses carotídeas mediram 70±11% (30-95%) em mulheres e 72±12% (40-98%) em homens (p=0,013). Prevalência de estenoses no intervalo 90-99% foi mais alta em homens, 14,3 vs 7,8% (p=0,029). As placas foram mais extensas nos homens, 2,3±0,8 vs 1,9±0,6 cm (p<0,001). O diâmetro médio foi maior nos homens, tanto da carótida interna distal, 4,9±0,9 vs 4,6±0,8 mm, como da carótida comum, 7,6±1,3 vs 7,1±1,4 mm (p=0.001). A distância da bifurcação ao lóbulo da orelha foi maior nos homens, 5,9±1,1 vs 5,3±0,9 cm (p<0,001). CONCLUSÕES: O mapeamento ecográfico demonstrou que as medidas analisadas foram maiores em pacientes do gênero masculino. O planejamento detalhado do tratamento da placa carotídea deve considerar diferenças individuais como as associadas ao gênero do paciente.

Dilatação fluxo-mediada da artéria braquial e complexo médio-intimal das artérias carótida e braquial: avaliação de indivíduos com e sem fatores de risco para aterosclerose

OBJETIVO: Avaliar a função endotelial em pacientes com fatores de risco para aterosclerose pela dilatação fluxo-mediada da artéria braquial (DILA) e complexo médio-intimal (CMI) das artérias carótida e braquial. MATERIAIS E MÉTODOS: Estudo transversal, caso controle, no qual foi avaliada a função endotelial pelo DILA e CMI das artérias carótida e braquial e presença ou não de fatores de risco para aterosclerose, em 112 pacientes assim distribuídos: mulheres com fatores de risco (n = 49), mulheres grupo controle (n = 24), homens com fatores de risco (n = 21) e homens grupo controle (n = 18). RESULTADOS: O DILA esteve comprometido significativamente no grupo fator de risco, quando comparado ao controle, independente do sexo: em mulheres, 15,2 × 25,3 (p < 0,01); em homens, 11,8 × 16,8 (p < 0,02). Já o CMI, tanto na braquial quanto na carótida, não foi significativo, independente do sexo: braquial em mulheres, 0,3 × 0,3 (p < 0,06); braquial em homens, 0,36 × 0,23 (p < 0,07); carótida em mulheres, 0,6 × 0,4 (p < 0,07); carótida em homens, 0,85 × 0,38 (p < 0,08). Utilizou-se como índice de significância p < 0,05. CONCLUSÃO: O DILA foi eficiente para atestar comprometimento endotelial em população de risco para aterosclerose