Multidetector computed tomography in transcatheter aortic valve replacement: an update on technological developments and clinical applications.

INTRODUCTION: Transcatheter aortic valve replacement (TAVR) has revolutionized the treatment of patients with underlying sever aortic valve stenosis across all spectrum of the disease. CT imaging is so crucial to the pre procedural planning, to incorporate the information from the CT imaging in the decision making intraprocedurally and to predict and identity the post procedural complications.Areas covered: In this article, we review available studies on CT role in TAVR procedure and provide update on the technological developments and clinical applications.Expert opinion: CT imaging, with its high resolution, and in particular its utilization in aortic annular measurements, bicuspid aortic valve assessment, hypoattenuated leaflet thickening and valve in valve therapy proved to be the ideal approach to study the mechanisms of aortic stenosis, detection of high-risk anatomy, more accurate risk stratification and thus to allow a personalized catheter based intervention of the affected patients.

The relationship between endothelial function and aortic valve calcification: Multi-Ethnic Study of Atherosclerosis.

BACKGROUND AND AIMS: Aortic valve calcification (AVC) may be associated with atherogenic processes arising from endothelial dysfunction (ED). Limited data is available about the relationship between ED, defined by flow mediated dilation (FMD%) and biomarkers, and the prevalence and progression of AVC in a multiethnic population. METHODS: A sample of 3475 individuals from the Multi-Ethnic Study of Atherosclerosis (MESA), with both initial and repeat CT scans at a mean of 2.65 ±â€¯0.84 years and FMD% and serologic markers of ED [ C-reactive protein (CRP), Von Willebrand factor (vWF), Plasminogen Activator Inhibitor (PAI), fibrinogen, Interleukin 6 (IL6), E-selectin and ICAM-1 (Intercellular Adhesion Molecule 1)], were analyzed. Multivariate modeling evaluated the association between ED and the prevalent AVC and AVC progression. RESULTS: The median levels of FMD% was lower and vWF%, fibrinogen, IL6 and ICAM-1 were significantly higher in the AVC prevalence group versus no AVC prevalence (all p < 0.001). In the fully adjusted model for established risk factors, decreasing FMD% or increasing biomarkers was not independently associated with AVC prevalence [OR FMD% 1.028 (0.786, 1.346), CRP 0.981 (0.825, 1.168), vWF 1.132 (0.559, 2.292), PAI 1.124 (0.960, 1.316), fibrinogen 1.116 (0.424, 2.940), IL6 1.065 (0.779, 1.456), E-selectin 0.876 (0.479, 1.602) and ICAM-1 1.766 (0.834, 3.743)]. In the AVC progression group, FMD%, vWF%, fibrinogen and IL6 were significantly different (p < 0.05). After adjusting for cardiac risk factors, AVC progression was not independently associated with decreasing FMD% or increasing biomarkers [OR FMD% 1.105 (0.835, 1.463), CRP 1.014 (0.849, 1.210), vWF% 1.132 (0.559, 2.292), PAI 1.124 (0.960, 1.316), fibrinogen 0.909 (0.338, 2.443), IL6 1.061 (0.772, 1.459), E-selectin 0.794 (0.426, 1.480) and ICAM-1 0.998 (0.476, 2.092)]. CONCLUSIONS: Endothelial dysfunction by FMD% and biomarkers is not significantly associated with the prevalence or progression of aortic valve calcification after adjustment for cardiac risk factors.

The Correlation of Dyslipidemia with the Extent of Coronary Artery Disease in the Multiethnic Study of Atherosclerosis.

BACKGROUND: The extent of coronary artery calcium (CAC) improves cardiovascular disease (CVD) risk prediction. The association between common dyslipidemias (combined hyperlipidemia, simple hypercholesterolemia, metabolic Syndrome (MetS), isolated low high-density lipoprotein cholesterol, and isolated hypertriglyceridemia) compared with normolipidemia and the risk of multivessel CAC is underinvestigated. OBJECTIVES: To determine whether there is an association between common dyslipidemias compared with normolipidemia, and the extent of coronary artery involvement among MESA participants who were free of clinical cardiovascular disease at baseline. METHODS: In a cross-sectional analysis, 4,917 MESA participants were classified into six groups defined by specific LDL-c, HDL-c, or triglyceride cutoff points. Multivessel CAC was defined as involvement of at least 2 coronary arteries. Multivariate Poisson regression analysis evaluated the association of each group with multivessel CAC after adjusting for CVD risk factors. RESULTS: Unadjusted analysis showed that all groups except hypertriglyceridemia had statistically significant prevalence ratios of having multivessel CAC as compared to the normolipidemia group. The same groups maintained statistical significance prevalence ratios with multivariate analysis adjusting for other risk factors including Agatston CAC score [combined hyperlipidemia 1.41 (1.06-1.87), hypercholesterolemia 1.55 (1.26-1.92), MetS 1.28 (1.09-1.51), and low HDL-c 1.20 (1.02-1.40)]. CONCLUSION: Combined hyperlipidemia, simple hypercholesterolemia, MetS, and low HDL-c were associated with multivessel coronary artery disease independent of CVD risk factors and CAC score. These findings may lay the groundwork for further analysis of the underlying mechanisms in the observed relationship, as well as for the development of clinical strategies for primary prevention.

Computer-aided analysis of 64- and 320-slice coronary computed tomography angiography: a comparison with expert human interpretation.

Routine use of CCTA to triage Emergency Department (ED) chest pain can reduce ED length of stay while providing accurate diagnoses. We evaluated the effectiveness of using Computer Aided Diagnosis in the triage of low to intermediate risk emergency chest pain patients with Coronary Computed Tomographic Angiography (CCTA). Using 64 and 320 slice CT scanners, we compared the diagnostic capability of computer aided diagnosis to human readers in 923 ED patients with chest pain. We calculated sensitivity, specificity, Positive Predictive Value and Negative Predictive Value for cases performed on each scanner. We calculated the area under the Receiver Operator Curve (ROC) comparing results for the two scanners to Computer Aided Diagnosis performance as compared to the human reader. We examined index and 30 Day outcomes by diagnosis for each scanner and the human reader. 60% of cases could be triaged by the computer. Sensitivity was approximately 85% for both scanners, with specificity at 50.6% for the 64 slice and at 56.5% for the 320 slice scanner (per person measures). The NPV was 97.8 and 97.1 for the 64 and 320 slice scanners, respectively. Results for the four major vessels were similar with negative predictive values ranging from 97 to 100%. The ROC for Computer Aided Diagnosis for the 64 and 320 Slice Scanners, using the human reader as the gold standard was 0.6794 and 0.7097 respectively. The index and 30 day outcomes were consistent for the human reader and Computer Aided Diagnosis interpretation. Although Computer Aided Diagnosis with CCTA cannot serve completely as a substitute for human reading, it offers excellent potential as a triage tool in busy EDs.

The Cardiovascular Trial of the Testosterone Trials: rationale, design, and baseline data of a clinical trial using computed tomographic imaging to assess the progression of coronary atherosclerosis.

BACKGROUND: Data from prior studies have yielded inconsistent results on the association of serum testosterone levels with the risk for cardiovascular disease. There are no clinical trial data on the effects of testosterone replacement therapy on plaque progression. OBJECTIVE: We designed a study to investigate the effect of testosterone therapy on coronary artery plaque progression using serial coronary computed tomographic angiography (CCTA). In this paper, we describe the study design, methods, and characteristics of the study population. METHODS: The Cardiovascular Trial of the Testosterone Trials (TTrials; NCT00799617) is a double-blind, placebo-controlled trial of 1 year of testosterone therapy in men 65 years or older with clinical manifestations of androgen deficiency and unequivocally low serum testosterone concentrations (<275 ng/dl). CCTA performed at baseline and after 12 months of therapy will determine the effects of testosterone on the progression of the total volume of noncalcified plaques. All scans are evaluated at a central reading center by an investigator blinded to treatment assignment. RESULTS: A total of 165 men were enrolled. The average age is 71.1 years, and the average BMI is 30.7. About 9% of men had a history of myocardial infarction, 6% angina, and 10% coronary artery revascularization. A majority reported hypertension and/or high cholesterol; 31.8% reported diabetes. Total noncalcified plaque at baseline showed a slight but nonsignificant trend toward lower plaque volume with higher serum testosterone concentrations (P=0.12). CONCLUSION: The Cardiovascular Trial will test the hypothesis that testosterone therapy inhibits coronary plaque progression, as assessed by serial CCTA.

Prevalence and correlates of mitral annular calcification in adults with chronic kidney disease: Results from CRIC study.

BACKGROUND: Risk factors for mitral annular calcification (MAC) and cardiovascular disease (CVD) demonstrate significant overlap in the general population. The aim of this paper is to determine whether there are independent relationships between MAC and demographics, traditional and novel CVD risk factors using cardiac CT in the Chronic Renal Insufficiency Cohort (CRIC) in a cross-sectional study. METHODS: A sample of 2070 subjects underwent coronary calcium scanning during the CRIC study. Data were obtained for each participant at time of scan. SUBJECTS: were dichotomized into the presence and absence of MAC. Differences in baseline demographic and transitional risk factor data were evaluated across groups. Covariates used in multivariable adjustment were age, gender, BMI, HDL, LDL, lipid lowering medications, smoking status, family history of heart attack, hypertension, diabetes mellitus, phosphate, PTH, albuminuria, and calcium. RESULTS: Our study consisted of 2070 subjects, of which 331 had MAC (prevalence of 16.0%). The mean MAC score was 511.98 (SD 1368.76). Age and white race remained independently associated with presence of MAC. Decreased GFR was also a risk factor. African American and Hispanic race, as well as former smoking status were protective against MAC. In multivariable adjusted analyses, the remaining covariates were not significantly associated with MAC. Among renal covariates, elevated phosphate was significant. CONCLUSION: In the CRIC population, presence of MAC was independently associated with age, Caucasian race, decreased GFR, and elevated phosphate. These results are suggested by mechanisms of dysregulation of inflammation, hormones, and electrolytes in subjects with renal disease.