Vahid Nabavi Larijani

Computed Tomography Scans in the Evaluation of Fatty Liver Disease in a Population Based Study: The Multi-Ethnic Study of Atherosclerosis

RATIONALE AND OBJECTIVES Fatty liver disease is a common clinical entity in hepatology practice. This study evaluates the prevalence and reproducibility of computed tomography (CT) measures for diagnosis of fatty liver and compares commonly used CT criteria for the diagnosis of liver fat. MATERIALS AND METHODS The study includes 6814 asymptomatic participants from a population-based sample. The ratio of liver-to-spleen (L/S) Hounsfield units (HU) <1.0 and liver attenuation <40 HU were used for diagnosing and assessing the severity of liver fat content. Participants with heavy alcohol intake (>7 drinks/week for women and >14 drinks/week for men) were excluded. Final analysis was performed on participants where images of both liver and spleen were available on the scans. RESULTS The overall prevalence of fatty liver (4175 subjects included in final analysis) was 17.2% (using L/S ratio <1.0), with 6.3% (with <40 HU cutoff) of the population having moderate to severe steatosis (>30% liver fat content). The prevalence was high in participants with dyslipidemia (70.4%), hypertension (56.8%), and obesity (53%). Diabetic patients had 24.1% prevalence of fatty liver. The prevalence provided by L/S ratio <1.0 (17.2%) was comparable to prevalence provided by <51 HU (17.3%), whereas prevalence obtained by <40 HU (6.3%) cutoff corresponded to L/S ratio of <0.8 (6.5%). The measurements of liver and spleen HU attenuations were highly reproducible (0.96, 0.99 and 0.99, 0.99 for intra- and inter-reader variability, respectively) in a sample of 100 scans. CONCLUSION Fatty liver can be reliably diagnosed using nonenhanced CT scans.

Aged garlic extract and coenzyme Q10 have favorable effect on inflammatory markers and coronary atherosclerosis progression: A randomized clinical trial.

Background: Aged garlic extract (AGE) and coenzyme Q10 (CoQ10) have been shown to affect multiple cardiovascular risk factors. The current study evaluates the effect of AGE combined with CoQ10 on inflammatory markers and progression of coronary atherosclerosis compared with placebo. Methods and Results: In this placebo-controlled, double-blind, randomized trial, 65 intermediate risk firefighters (age 55 ± 6 years) were treated with a placebo capsule or a capsule containing AGE and CoQ10 (AGE+CoQ10, 1200 and 120 mg, respectively) daily for 1 year. All participants underwent coronary artery calcium (CAC) scanning and C-reactive protein (CRP) at baseline and at 12 months. At 1 year, mean CAC progression was significantly lower in AGE+CoQ10 (32 ± 6 vs. 58 ± 8, P = 0.01) than placebo. Similarly, CRP were significantly decreased in AGE+CoQ10 compared with placebo (-0.12 ± 0.24 vs. 0.91 ± 0.56 mg/L, P < 0.05). After adjustment for age, gender, conventional cardiac risk factors, and statin therapy, AGE+CoQ10 was associated with 3.99 fold (95% 1.3–12.2, P = 0.01) lack of CAC progression compared with the placebo. Conclusion: AGE+CoQ10 are associated with beneficial effects on inflammatory markers and reduced progression of coronary atherosclerosis.

Beneficial effects of aged garlic extract and coenzyme Q10 on vascular elasticity and endothelial function: The FAITH randomized clinical trial

OBJECTIVE Aged garlic extract (AGE) is associated with a significant decrease in atherosclerotic plaque progression and endothelial function improvement. Similarly, coenzyme Q10 (CoQ10) has significant beneficial effects on endothelial function. A stressful lifestyle is a well-known risk factor for the presence and progression of atherosclerosis. This study investigated the effect of AGE plus CoQ10 on vascular elasticity measured by pulse-wave velocity (PWV) and endothelial function measured by digital thermal monitoring (DTM) in firefighters. METHODS Sixty-five Los-Angeles County firefighters who met the eligibility criteria were enrolled in this placebo-controlled, double-blinded randomized trial. The firefighters were randomized to four tablets of AGE (300 mg/tablet) plus CoQ10 (30 mg/tablet) or placebo. The participants underwent quarterly visits and 1-year follow-up. PWV and DTM were measured at baseline and at the 1-year follow-up. RESULTS There were no significant differences in age, cardiovascular risk factors, PWV, and DTM between the AGE/CoQ10 and placebo groups at baseline (P > 0.5). At 1-y, PWV and DTM significantly improved in the AGE/CoQ10 compared with the placebo group (P < 0.05). After an adjustment for cardiovascular risk factors and statin therapy, the mean decrease in vascular stiffness (PWV) was 1.21 m/s in the AGE/CoQ10 compared with the placebo group (P = 0.005). Similarly, the mean increase in the area under the temperature curve, the DTM index of endothelial function, was 31.3 in the AGE/CoQ10 compared with the placebo group (P = 0.01). CONCLUSION The combination of AGE and CoQ10 was independently associated with significant beneficial effects on vascular elasticity and endothelial function in firefighters with high occupational stress, highlighting the important role of AGE and CoQ10 in atherosclerotic prevention of such individuals.

The diagnostic accuracy of 64-detector cardiac computed tomography compared with stress nuclear imaging in patients undergoing invasive cardiac catheterization.

Objective: The aim of this study was to evaluate the diagnostic accuracy of nuclear stress imaging as compared with noninvasive coronary artery imaging using 64-detector row cardiac computed tomography. Background: Compared with invasive coronary angiography, multidetector row cardiac computed tomographic angiography (CTA) has shown promise in the accurate detection of coronary stenosis. Myocardial perfusion imaging (MPI) using single photon emission computed tomography is an established method for noninvasively assessing the functional significance of coronary stenosis. This study compared the accuracy of CTA and that of MPI in the detection of relevant lesions of coronary arteries. Methods: One hundred twenty-two symptomatic patients (77% males) with cardiac catheterization who also underwent MPI and CTA evaluations within 6 months at 2 centers were included. Comparison of CTA for lesions causing greater than 50% and greater than 70% coronary narrowing versus respective lesions on invasive cardiac catheterization (IC) was performed. Similarly, comparison of MPI findings with greater than 50% and greater than 70% lesions on IC was done. Results: The per-patient sensitivity, specificity, and positive and negative predictive values in detecting greater than 50% coronary lesions on IC for CTA were 98.9%, 74.2%, 91.8%, and 95.8%, respectively; and for MPI, 56%, 38.7%, 72.9%, and 23%, respectively. The sensitivity, the specificity, and the positive and negative predictive values in detecting greater than 70% coronary lesions on IC for CTA were 89.7%, 86.4%, 92.1%, and 82.6%, respectively; and for MPI, 57.7%, 43.2%, 64.3%, and 36.5%, respectively. The prevalence of significant coronary artery disease on cardiac catheterization was 74.6% for greater than 50% stenosis and 63.9% for greater than 70% stenosis. Conclusions: Compared with MPI, CTA provided important information and identified significant lesions in symptomatic intermediate- to high-risk patients. Cost-effective and prospective multicentered studies, currently underway, are needed to further establish the best use of these diagnostic tests in the evaluation of coronary artery disease.

Association of plaque in the carotid and coronary arteries, using MDCT angiography

OBJECTIVE Associations between various plaque types in coronary and carotid arteries using multidetector row computed tomography (MDCT) have not yet been reported. We evaluated MDCT correlation of total plaque and various plaque subtypes in carotid and coronary arteries. METHODS We studied 62 patients who had both carotid and cardiac computed tomography angiography (CTA). The plaque in each vascular segment was classified as non-calcified, calcified or mixed. RESULTS The average age of this population was 68+/-22 years, 63% males. Total plaque in the carotid artery correlated with total, calcified and mixed plaque in the coronary artery (all P<0.001). Calcified plaque in the carotid artery was associated with total and calcified plaque in the coronary bed (P<0.001). Non-calcified coronary plaque was not associated with carotid plaque. CONCLUSION Total plaque in coronary and carotid arteries are highly correlated.

AGED GARLIC EXTRACT WITH SUPPLEMENT SLOWED THE PROGRESSION OF METABOLICALLY ACTIVE EPICARDIAL ADIPOSE TISSUE, INFLAMMATION AND CORONARY ATHEROSCLEROSIS: A RANDOMIZED CLINICAL TRIAL

Methods: Sixty asymptomatic subjects, randomized to AGE-S vs. placebo, underwent CT at baseline and 12-month, and their CAC, mEAT and inflammatory biomarkers were measurement. mEAT, adipose tissue inside pericardial sac with Hounsfield unit -10 to -87, was measured from slice level 15 mm above to the bottom of the heart. The content of oxidized phospholipids (OxPL) on apolipoprotein B-100 (apoB) particles detected by antibody E06 (OxPL/apoB), lipoprotein(a), IgG and IgM autoantibodies to malondialdehyde-low-density lipoprotein and apoB-immune complexes were measured. CAC progression was defined as an annual increase in CAC >15%.

AGED GARLIC EXTRACT AND COENZYME Q10 HAS FAVORABLE EFFECT ON OXIDATIVE AND INFLAMMATORY MARKERS AND CORONARY ATHEROSCLEROSIS PROGRESSION

Aged garlic extract (AGE) and Coenzyme Q10 (CoQ10) has been shown to affect multiple cardiovascular risk factors. The current study evaluates the effect of AGE combined with CoQ10 on inflammatory and oxidative markers and progression of coronary atherosclerosis compared with placebo. In this

IMPAIRED CORONARY DISTENSIBILITY, METABOLIC STATUS AND INCREASED SUBCLINICAL ATHEROSCLEROSIS

Results: CDI was lower in DM as compared to normoglycemics (2.84±0.54 vs. 5.81±0.47). Inversely, CAC was higher in DM than normoglycemics (p<0.05). The risk of each standard deviation (SD) decrease of CDI was 2.77 in DM as compared to normoglycemics; also, the risk of each CAC category increase was 1.92 in DM after adjustment for risk factors. Subjects with lowest tertile of CDI and DM had the maximum CAC (Figure)

ACCURATE CARDIAC FUNCTION ASSESSMENT DURING TIMING BOLUS PHASE OF COMPUTED TOMOGRAPHY ANGIOGRAPHY: VALIDATION STUDY

Methods: Eighty three subjects (age 63±10, 34% female) underwent CTA. RV and LV ejection fraction (EF) were measured using Simpson’s method and timing bolus method. Based on Dye dilution technique, the RV and LV EF were measured during timing bolus contrast injection. RVEF was calculated as: (peak hounsfield-unit(HU) in pulmonary artery(PA)/ peak HU in superior vena cava)*(time to peak HU in PAtime to peak HU in SVC)/100.LVEF calculated as:(peak HU in ascending aorta(AA)/ peak HU in PA))*(time to peak HU in AAtime to peak HU in PA)/100.