Sina Rahmani

Imaging Atherosclerosis in Diabetes: Current State

Cardiovascular events, including myocardial infarction and stroke, are the primary causes of mortality in both type 1 and type 2 diabetes. Affected patients frequently have asymptomatic coronary artery disease. Studies have shown heterogeneity in cardiovascular risk among patients with diabetes. Imaging can help categorize risk of future cardiovascular events by identifying those patients with atherosclerosis, rather than relying on risk prediction based on population-based studies. In this article, we will review the evidence regarding use of atherosclerosis imaging in patients with diabetes to predict risk of coronary heart disease and mortality.

Rationale and design of a randomized trial of apixaban vs warfarin to evaluate atherosclerotic calcification and vulnerable plaque progression

Vitamin K antagonists (VKAs) are known to increase vascular calcification, suggesting increased cardiovascular disease events. Apixaban is an oral direct factor Xa inhibitor superior to warfarin at preventing stroke or systemic embolism and may stabilize coronary atherosclerosis. The potential benefits of avoiding VKA therapy and the favorable effects of factor Xa inhibitors could contribute to cardiovascular disease event reduction. We hypothesized that apixaban inhibits vascular calcification and coronary atherosclerosis progression compared with warfarin in patients with atrial fibrillation (AF). This study is a single‐center, prospective, randomized, open‐label study. From May 2014 to December 2015, 66 patients with nonvalvular AF who experienced VKA therapy were enrolled. Patients were randomized into either warfarin or apixaban cohorts and followed for 52 weeks. The primary objective is to compare the rate of change in coronary artery calcification (CAC) from baseline to follow‐up in apixaban vs warfarin cohorts. The key secondary objective is to compare the rate of incident plaques and quantitative changes in plaque types between patients randomized to either warfarin or apixaban cohorts using serial coronary computed tomography angiography. Expert readers will blindly assess CAC and coronary artery plaques. It is thought that this trial will result in significant differences in CAC and coronary artery plaque progression between the VKA and apixaban. The results are anticipated to provide a novel insight into treatment selection for AF patients. The study is registered at http://www.clinicaltrials.gov (NCT 02090075).

Automated estimation of image quality for coronary computed tomographic angiography using machine learning

ObjectivesOur goal was to evaluate the efficacy of a fully automated method for assessing the image quality (IQ) of coronary computed tomography angiography (CCTA).MethodsThe machine learning method was trained using 75 CCTA studies by mapping features (noise, contrast, misregistration scores, and un-interpretability index) to an IQ score based on manual ground truth data. The automated method was validated on a set of 50 CCTA studies and subsequently tested on a new set of 172 CCTA studies against visual IQ scores on a 5-point Likert scale.ResultsThe area under the curve in the validation set was 0.96. In the 172 CCTA studies, our method yielded a Cohen’s kappa statistic for the agreement between automated and visual IQ assessment of 0.67 (p < 0.01). In the group where good to excellent (n = 163), fair (n = 6), and poor visual IQ scores (n = 3) were graded, 155, 5, and 2 of the patients received an automated IQ score > 50 %, respectively.ConclusionFully automated assessment of the IQ of CCTA data sets by machine learning was reproducible and provided similar results compared with visual analysis within the limits of inter-operator variability.Key points• The proposed method enables automated and reproducible image quality assessment.• Machine learning and visual assessments yielded comparable estimates of image quality.• Automated assessment potentially allows for more standardised image quality.• Image quality assessment enables standardization of clinical trial results across different datasets.

HIV INFECTION IS ASSOCIATED WITH INCREASED LEFT VENTRICULAR MASS IN THE MULTICENTER AIDS COHORT STUDY (MACS)

HIV infection is associated with increased risk for cardiovascular events, heart failure and atrial fibrillation; however, underlying mechanisms are not fully understood. We evaluated the association between HIV serostatus and left-ventricular mass (LVM), left-ventricular end-diastolic volume (LVEDV

Correlation of Arterial Stiffness With Left Atrial Volume Index and Left Ventricular Mass Index in Young Adults: Evaluation by Coronary Computed Tomography Angiography

BACKGROUND Increased arterial stiffness is reportedly associated with cardiac remodelling, including the left atrium and left ventricle, in middle-aged and older adults. However, little is known about this association in young adults. METHODS In total, 73 patients (44 (60%) men) aged 25 to 45 years with suspected coronary artery disease were included in the analysis. The left atrial volume index (LAVI), left ventricular volume index (LVVI), and left ventricular mass index (LVMI) were measured using coronary computed tomography angiography (CCTA). Arterial stiffness was assessed with the cardio-ankle vascular index (CAVI). An abnormally high CAVI was defined as that above the age- and sex-specific cut-off points of the CAVI. RESULTS Compared with patients with a normal CAVI, those with an abnormally high CAVI were older and had a greater prevalence of diabetes mellitus, higher diastolic blood pressure, greater coronary artery calcification score, and a greater LAVI (33.5±10.3 vs. 43.0±10.3mL/m2, p <0.01). In contrast, there were no significant differences in the LVVI or LVMI between the subgroups with a normal CAVI and an abnormally high CAVI. Multivariate linear regression analysis showed that the LAVI was significantly associated with an abnormally high CAVI (standardised regression coefficient=0.283, p=0.03). CONCLUSIONS The present study demonstrated that increased arterial stiffness is associated with the LAVI, which reflects the early stages of cardiac remodelling, independent of various comorbidity factors in young adults with suspected coronary artery disease.

Ischemic stroke/transient ischemic attack events and carotid artery disease in the absence of or with minimal coronary artery calcification: Results from the Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS The association between minimally elevated coronary artery calcification (CAC) and cerebrovascular disease is not well known. We assessed whether individuals with minimal CAC (Agatston scores of 1-10) have higher ischemic stroke or transient ischemic attack (TIA) frequencies compared with those with no CAC. We also investigated the relative prevalence of carotid atherosclerosis in these two groups. METHODS A total of 3924 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) without previous cardiovascular events, including stroke, and with baseline CAC scores of 0-10 were followed for the occurrence of incident ischemic stroke/TIA. We used carotid ultrasound to detect carotid artery plaques and to measure the intima-media thickness (IMT). RESULTS During a median follow-up of 13.2 years, 130 participants developed incident ischemic stroke/TIA. There was no significant difference in the ischemic stroke/TIA incidence between those with minimal CAC and no CAC (3.7 versus 2.7 per 1000 person-years). In participants with minimal CAC, we observed a significant association of the condition with an internal carotid artery (ICA) that had a greater-than-average IMT (ICA-IMT; β = 0.071, p = 0.001) and a higher odds ratio (OR) for carotid artery plaques (OR 1.46; with a 95% confidence interval [CI] of 1.18-1.80; p < 0.001). CONCLUSIONS A CAC score of 0-10 is associated with a low rate of ischemic stroke/TIA, and thus a minimal CAC score is not a valuable predictive marker for ischemic stroke/TIA. A minimal CAC score may, however, provide an early and asymptomatic sign of carotid artery disease.

IMPACT OF CARDIAC TROPONIN I ON THE PRESENCE OF THE CORONARY ARTERY PLAQUE IN RHEUMATOID ARTHRITIS PATIENTS

Introduction: The presence of accelerated coronary artery disease in rheumatoid arthritis (RA) was previously reported. The goal of this study was to investigate if using high sensitivity cardiac troponin I (hs-cTnI) identifies patients at higher coronary atherosclerosis risk. Method: A total of

ASSOCIATION OF TOTAL TESTOSTERONE WITH PROGRESSION OF CAROTID ATHEROSCLEROSIS AND CORONARY ARTERY CALCIUM SCORE: THE MULTI-ETHNIC STUDY OF ATHEROSCLEROSIS

Background: Studies investigating testosterone (T) as a cardiovascular (CV) risk factor are controversial. We aimed to determine association of total T with progression of coronary artery calcium (CAC) score, carotid intima-media thickness (cIMT) and new carotid plaque formation. Methods: Male

THE UTILITY OF LEFT ATRIAL APPENDAGE HOUNSFIELD UNIT AND THE RATIO OF LEFT ATRIAL APPENDAGE/ASCENDING AORTA HOUNSFIELD UNIT FOR DETECTING LEFT ATRIAL APPENDAGE THROMBUS

Background: Atrial fibrillation (AF) increases the risk of thromboembolic events by promoting thrombus formation in the left atrial appendage (LAA). Delayed enhancement by cardiac computed tomography angiography (CCTA) is a reliable method in evaluating LAA thrombus. Previously, studies using CCTA

THE UTILITY OF MINIMAL CORONARY ARTERY CALCIFICATION FOR PREDICTING CAROTID ARTERY DISEASE: RESULTS FROM THE MULTI-ETHNIC STUDY OF ATHEROSCLEROSIS (MESA)

Background: An elevated CAC (coronary artery calcification) is a marker of increased cerebrovascular disease risk. However, cerebrovascular events also occur in individuals with little or no CAC. In this study, we aim to assess whether individuals with minimal CAC (1-10) have similar or higher