ABSTRACT
We determined whether increased carotid intima-media thickness (cIMT) and prevalence of carotid plaque (CP) are predictive of prevalence and severity of coronary atherosclerosis. Consecutive patients (n = 150) with no history of coronary artery disease (CAD), who underwent both carotid ultrasound and computed tomographic coronary angiography, were included in the analysis. The mean cIMT was higher in patients with CAD than in those without CAD (0.76 vs 0.66 mm, P < .003). In a logistic regression analysis, diabetes (P = .03) and CP (P = .02) were associated with significant coronary plaque. Backward selection analysis (after removing nonsignificant variables) showed higher mean cIMT measurement correlated well with prevalence of any coronary plaque (P = .03) and obstructive coronary plaque disease (P = .05), whereas presence of CP was a good predictor of both obstructive (>50% stenosis P = .003) and any coronary plaque (P = .003). In conclusion, CP and cIMT can be useful predictors of prevalence of CAD and its severity.
Subject(s)
Carotid Arteries/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Carotid Intima-Media Thickness , Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Coronary Vessels/diagnostic imaging , Plaque, Atherosclerotic , Tomography, X-Ray Computed , Aged , Carotid Artery Diseases/epidemiology , Coronary Artery Disease/epidemiology , Female , Humans , Logistic Models , London/epidemiology , Male , Middle Aged , Odds Ratio , Pilot Projects , Predictive Value of Tests , Prevalence , Risk Factors , Severity of Illness IndexABSTRACT
We have described a myocardial infarct scar identified by a standard dual source CT coronary angiography (CTCA). We were able to detect the scar during the routine coronary assessment without contrast late enhancement and without additional radiation exposure. It is therefore feasible to assess chronic scar using a standard CTCA technique.
ABSTRACT
BACKGROUND: CT coronary angiography (CTCA) is an evolving modality for the diagnosis of coronary artery disease. Radiation burden associated with CTCA has been a major concern in the wider application of this technique. It is important to reduce the radiation dose without compromising the image quality. OBJECTIVES: To estimate the radiation dose of CTCA in clinical practice and evaluate the effect of dose-saving algorithms on radiation dose and image quality. METHODS: Effective radiation dose was measured from the dose-length product in 616 consecutive patients (mean age 58 ± 12 years; 70% males) who underwent clinically indicated CTCA at our institution over 1 year. Image quality was assessed subjectively using a 4-point scale and objectively by measuring the signal- and contrast-to-noise ratios in the coronary arteries. Multivariate linear regression analysis was used to identify factors independently associated with radiation dose. RESULTS: Mean effective radiation dose of CTCA was 6.6 ± 3.3 mSv. Radiation dose was significantly reduced by dose saving algorithms such as 100 kV imaging (-47%; 95% CI, -44% to -50%), prospective gating (-35%; 95% CI, -29% to -40%) and ECG controlled tube current modulation (-23%; 95% CI, -9% to -34%). None of the dose saving algorithms were associated with a significant reduction in mean image quality or the frequency of diagnostic scans (P = non-significant for all comparisons). CONCLUSION: Careful application of radiation-dose saving algorithms in appropriately selected patients can reduce the radiation burden of CTCA significantly, without compromising the image quality.
Subject(s)
Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Radiation Dosage , Tomography, X-Ray Computed/methods , Algorithms , Cardiac-Gated Imaging Techniques , Contrast Media , Cross-Sectional Studies , Female , Humans , Linear Models , Male , Middle Aged , Prospective Studies , Signal-To-Noise Ratio , Statistics, NonparametricABSTRACT
BACKGROUND: Epicardial adipose tissue (EAT), a metabolically active visceral fat depot surrounding the heart, has been implicated in the pathogenesis of coronary artery disease (CAD) through possible paracrine interaction with the coronary arteries. We examined the association of EAT with metabolic syndrome and the prevalence and progression of coronary artery calcium (CAC) burden. METHODS: CAC scan was performed in 333 asymptomatic diabetic patients without prior history of CAD (median age 54 years, 62% males), followed by a repeat scan after 2.7±0.3 years. CAC progression was defined as >2.5mm(3) increase in square root transformed volumetric CAC scores. EAT and intra-thoracic fat volumes were quantified using a dedicated software (QFAT), and were examined in relation to the metabolic syndrome, baseline CAC scores and CAC progression. RESULTS: Both epicardial and intra-thoracic fat were associated with metabolic syndrome after adjustment for conventional cardiovascular risk factors, but the association was attenuated after additional adjustment for body mass index. EAT, but not intra-thoracic fat, showed significant association with baseline CAC scores (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.04-1.22, p=0.04) and CAC progression (OR 1.12, 95% CI 1.05-1.19, p<0.001) after adjustment for conventional measures of obesity and risk factors. CONCLUSION: EAT volume measured on non-contrast CT is an independent marker for the presence and severity of coronary calcium burden and also identifies individuals at increased risk of CAC progression. EAT quantification may thus add to the prognostic value of CAC imaging.
