Prior History Of Coronary Artery Disease Research Articles

Use of observation followed by outpatient stress testing in chest pain patients with prior coronary artery disease history: An evaluation of prognostic utility

ObjectiveTo determine the outcomes of patients with chest pain (CP) and prior history of coronary artery disease (CAD) managed with observation followed by outpatient stress myocardial perfusion imaging (MPI). MethodsRetrospective analysis of patients with CP managed with observation followed by outpatient stress MPI, comparing cardiovascular (CV) event rates stratified by CAD history. Results375 patients were included: 111 with and 264 without a CAD history. All patients underwent outpatient stress MPI within 72h of observation. MPI identified patients at risk for CV events. However, while patients with negative MPI and without a CAD history had very low rates of short- and long-term CAD events (0.8%, 0.8%, and 1.3% at 30days, 1year, and 3years, respectively), event rates of those with a negative test but a CAD history were significantly higher (2.6%, 5.3%, and 6.6% at 30days, 1year and 3years, respectively; p=0.044 and p=0.034 compared to CAD− patients at 1year and 3years, respectively). In a multivariable logistic regression model, a positive MPI proved to be an independent predictor of long-term CV events in patients with CP and prior CAD. ConclusionObservation followed by stress MPI can effectively risk stratify CP patients with prior CAD for CV risk. These patients are at increased risk of CV events even after a low-risk stress MPI study. Patients presenting with CP and managed with a strategy of observation followed by a negative stress MPI warrant close short- and long-term monitoring for recurrent events.

Abstract 212: Temporal Trends of SPECT Myocardial Perfusion Imaging in Patients with Coronary Heart Disease: A 22-Year Experience from a Tertiary Academic Medical Center

Background: Over the past 20 years, there has been an increasing decline in the prevalence of abnormal stress single-photon emission computed tomography myocardial perfusion imaging (SPECT) studies among patients with no history of coronary artery disease (CAD). The trend of SPECT studies among patients with known CAD has not been evaluated before. Methods: Using the Mayo Clinic nuclear cardiology database, we examined all stress SPECT tests performed between 1/1991-12/2012 in patients with prior history of CAD defined as having prior myocardial infarction, percutaneous coronary intervention, and/or coronary artery bypass grafting. Patients with left bundle branch block, paced rhythm, bicycle or rest-only tests, cardiomyopathy, valvular heart disease, and technically unsatisfactory studies were excluded. The study cohort was divided into 5 time periods: 1991-5, 1996-2000, 2001-5, 2006-10, and 2011-12. Results: There were 19373 eligible SPECT tests (mean age 66.2 ± 10.9y, 75.4% men). Annual utilization of SPECT studies in patients with history of CAD increased from an average of 495 tests per year between 1991-1995 to a peak of 1425 in 2003; and then decreased to 552 tests in 2012. Asymptomatic patients comprised 33% in 1991-1995, peaked at 48% in 2006, and then decreased back to 31% in 2012. Over time, patients with typical angina decreased while patients with dyspnea increased, P <0.001 (Fig 1). The percentage of high risk SPECT tests significantly decreased, and the percentage of low-risk SPECT tests significantly increased despite the overall decline of SPECT utilization between 2003 and 2012. Almost 80% of all tests performed in 2012 had a low risk summed stress score compared to 29% in 1991, P <0.001 (Fig 2). Conclusions: In Mayo Clinic Rochester, annual SPECT utilization in patients with prior CAD increased between 1992 and 2003, but then decreased significantly after 2003. Fewer patients had typical angina while patients with dyspnea increased over time. High risk SPECT tests declined while low risk tests increased dramatically. These data suggest that stress SPECT was being increasingly utilized in CAD patients without typical angina who are at low risk.

Myocardial perfusion scintigraphy: interpretation of a normal scan

Myocardial perfusion scintigraphy: interpretation of a normal scan

Negative predictive value of SPECT for the occurrence of MACE in a medium-sized clinic in the Netherlands

BackgroundSingle-photon emission computed tomography (SPECT) is an important prognostic tool in evaluating coronary artery disease (CAD), with a high negative predictive value (NPV) for the occurrence of major adverse cardiac events (MACE). The prognostic value of SPECT is disputed in women, patients with atrial fibrillation (AF), diabetes, left bundle branch block (LBBB) and renal impairment.MethodsSeven hundred sixty-two patients without prior history of CAD who had SPECT without perfusion deficits were followed for 2 years for MACE. Predictive variables for the occurrence of MACE were reviewed by Cox proportional hazard regression, considering clinical information, resting-ECG data and SPECT data.ResultsThe NPV of SPECT for the occurrence of MACE within 2 years was 95.8 %. Multivariate Cox regression revealed male gender as the only significant predictor for the occurrence of MACE, besides a positive stress ECG at SPECT and a low LVEF. AF, LBBB, renal impairment and diabetes had no significant effect on the prognosis after normal SPECT.ConclusionSPECT with normal perfusion images has great NPV in a medium-sized clinic in the Netherlands, even in patients with LBBB, AF, diabetes and renal impairment. MACE-free survival, however, was negatively influenced by male gender; we therefore propose more caution in men.

Reliable exclusion of acute coronary syndrome among hospitalized patients with elevated troponin.

Elevated cardiac troponin I (cTnI) occurs in acute coronary syndrome (ACS) as well as various scenarios not associated with ACS. Simple clinical criteria can reliably exclude ACS among hospitalized patients with elevated cTnI. Records for patients hospitalized from January to April 2011 with elevated cTnI (>0.29 ng/dL) and an available echocardiogram were retrospectively reviewed. Patients with ST-segment elevation myocardial infarction were excluded. Based on available clinical data, patients were classified as having ACS or elevation of cTnI unrelated to ACS (non-ACS). Median follow-up was 365 days. Of 265 records meeting inclusion criteria, 82 (31%) had ACS and 183 (69%) had non-ACS. In multivariable analysis, odds ratios for non-ACS were 7.6 (95% confidence interval [CI]: 3.8-15.3) for peak cTnI <2 ng/dL, 6.3 (95% CI: 3.1-13.0) for absent wall-motion abnormality, and 4.4 (95% CI: 2.2-8.6) for no prior coronary artery disease history. The area under the receiver operating curve for amodel using these 3 variables was 0.86, with a 98% negative predictive value for excluding ACS. Patients who met these 3 criteria had no ACS-related deaths over 1-year follow-up. Hospitalized patients with peak Tn level<2 ng/dL, no prior history of coronary artery disease, and no new echocardiographic wall-motion abnormality appear to have a very low likelihood of ACS. Prospective validation of these results is needed to determine whether additional diagnostic testing could be safely avoided in hospitalized patients meeting these simple clinical criteria.

Association of asymmetric dimethylarginine levels with treadmill-stress-test-derived prognosticators

BackgroundAsymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide production. The purpose of this study was to assess the correlation between ADMA and treadmill stress test outcome parameters with known prognostic value, in patients with intermediate risk for coronary artery disease (CAD). MethodsStudy participants were referred for treadmill exercise stress test (EST) due to symptoms of suspected CAD. Participants with prior history of CAD, cerebrovascular events, peripheral artery disease, systemic inflammatory disease or use of anti-inflammatory agents were excluded. ADMA levels were measured before EST. ResultsThe study prospectively enrolled 209 individuals (165 males, aged 58.1±10.9). A significant negative correlation was detected between ADMA and maximal exercise time (r=−0.556, p<0.001), metabolic equivalents (METs) (r=−0.555, p<0.001) and Duke treadmill score (DTS) (r=−0.347, p<0.001). Subjects who exercised to ≥10 METs (n=114) had lower ADMA levels than those who achieved <7 METs (n=30) (0.58±0.06 vs 0.87±0.08μmol/L, p<0.001), and those with DTS<5 (n=63) had higher ADMA (0.75±0.19 vs 0.64±0.15μmol/L, p<0.001) compared to those with DTS ≥5 (n=146). In multivariable analysis, ADMA remained an independent predictor of DTS (R2=0.210; beta=−10.5; 95% confidence interval −14.9 to −6.2; adjusted p<0.001) and METs (R2=0.500; beta −8.5; 95% confidence interval −9.7 to −6.0; adjusted p<0.001) after adjustment for age, BMI, gender, diabetes, smoking status, dyslipidemia, hypertension and family history of premature CAD. ConclusionADMA is correlated to EST parameters with proven prognostic value. This implies that ADMA itself might be a useful prognosticator in patients with suspected CAD.

Abstract 18490: The Use of a Personalized Gene Expression Score in Women Presenting to Primary Care With Symptoms of Suspected Obstructive Coronary Artery Disease Improves Clinical Decision Making Around Non-Invasive Diagnostic Testing: Gender-Specific Results From the IMPACT-PCP (Investigation of a Molecular Personalized Coronary Gene Expression Test on Primary Care Practice Pattern) Trial

Introduction: Better methods are needed to evaluate symptomatic patients with suspected obstructive coronary artery disease (CAD), particularly among women as current methods overestimate disease prevalence. A previously validated blood-based diagnostic test with a negative predictive value of 96% among patients with low gene expression score (GES ≤ 15) uses expression levels of 23 genes to determine the likelihood of a patient having at least one vessel with ≥50% coronary artery stenosis. Use of a GES early in the diagnostic work-up for obstructive CAD may impact quality and efficiency of care. Hypothesis: In this gender-based analysis, we hypothesized that GES results would lead to a change in the clinician’s diagnostic assessment of women presenting with symptoms suggestive of obstructive CAD. Methods: The IMPACT-PCP Trial ( NCT01594411 ) evaluated 251 consecutive patients with no prior history of CAD who presented to nine primary care clinicians for evaluation of chest pain and related symptoms and underwent GES testing. The clinicians outlined their diagnostic strategy before and after GES results were known. The primary outcome was the decision change in the diagnostic strategy pre/post GES testing as measured by regression modeling. In this pre-specified secondary analysis, we focused on the assessment of women in this prospective cohort. Results: There were 140 women (56%) eligible for analysis, with mean age 59 years (SD± 13). Mean GES was 11 (SD± 9), with 76% (n=107) of women patient with low GES. Following GES, a change in the evaluation plan was noted in 83 patients (59% observed vs 10% expected change, p&lt;0.001). More patients had a decreased (n=69, 49%) vs increased (n=14, 10%) intensity of testing (p&lt;0.001). In particular, 96% (66/69) of patients with decreased testing had low GES (≤ 15), while 93% (13/14) of patients with increased testing had elevated GES. There has been one MACE event reported (judged as not related to CAD status by the clinician) over 30 days of follow-up. Conclusions: The GES showed clinical utility in the evaluation of suspected obstructive CAD by affecting clinical decision making among primary care practitioners and was associated with an overall relevant reduction in diagnostic test utilization among women with low GES.

Elevated troponin I levels but not low grade chronic inflammation is associated with cardiac-specific mortality in stable hemodialysis patients

BackgroundElevated cardiac troponin I (TnI) levels are associated with all-cause mortality in stable hemodialysis patients. Their relationship to cardiac-specific death has been inconsistent, and the reason for their elevation is not well understood. We hypothesized that elevated TnI levels in chronic stable hemodialysis patients more specifically track with cardiac mortality, and this mechanism is independent of other contributors of cardiac mortality, such as inflammation.MethodsWe conducted a single-centre, cohort study of prevalent hemodialysis patients at a tertiary care hospital. Plasma TnI levels were measured with routine monthly blood tests in clinically stable patients for two consecutive months. Plasma TnI was measured by immunoassay and a value above the laboratory reference range (0.06 μg/L) was considered elevated. The primary outcome of death was adjudicated separately for this study, and classified as cardiac, non-cardiac, or unknown. Cox proportional hazard models were used to examine the association of TnI with the all-cause and cardiac-specific mortality, adjusting for potential confounders, including C-reactive protein (CRP) as a marker of inflammation.ResultsOf 133 patients followed for a median of 1.7 years, there were 38 deaths (58% non-cardiac, 39% cardiac, 3% unknown). Elevated TnI was associated with adjusted HR for all-cause mortality of 2.57 (95% CI 1.30-5.09) and an adjusted HR for cardiac death of 3.14 (95% CI 1.07-9.2), after accounting for age, time on dialysis, diabetes status, prior coronary artery disease history, and C-reactive protein. Although CRP was also independently associated with all-cause mortality, it did not add prognostic information to TnI for cardiac-specific death.ConclusionElevated TnI levels are independently associated with cardiac and all-cause mortality in asymptomatic hemodialysis patients. The mechanism for this risk is likely independent of inflammation, but may reflect chronic subclinical myocardial injury or unmask those with subclinical atherosclerotic heart disease. Whether those with elevated TnI levels may benefit from additional investigations or more aggressive therapies to treat cardiovascular disease remains to be determined.

Effects of a fish-based diet and administration of pure eicosapentaenoic acid on brachial-ankle pulse wave velocity in patients with cardiovascular risk factors

Background and purposeBrachial-ankle pulse wave velocity (baPWV) and ratio of plasma eicosapentaenoic acid to arachidonic acid (EPA/AA ratio) are surrogate markers for coronary artery disease (CAD). We aimed to evaluate the effects of a fish-based diet and administration of EPA on baPWV and plasma EPA/AA ratio. Methods and resultsThe changes in baPWV and plasma EPA/AA ratio were compared before and after a 6-month fish-based diet in 191 patients with cardiovascular risk factors. A fish-based diet resulted in significant increment of plasma EPA/AA ratio (0.40±0.18 vs. 0.49±0.27, p<0.001), with baPWV remaining unchanged. Multivariate analysis revealed that systolic blood pressure (SBP) (6-month SBP-baseline SBP) and CAD were positively associated with increased baPWV (CAD: odds ratio=2.040, p=0.0436, SPB: odds ratio=1.056, p=0.0003). When the patients were divided into three groups: CAD, low-risk, and high-risk with no prior history of CAD according to the number of risk factors at baseline, comparison among the three groups disclosed an inter-group difference in the magnitude of change in baPWV (low-risk: −35±164cm/s, high-risk: −14±190cm/s, CAD: 39±164cm/s, p=0.0071 for trend). In 191 patients who had received a 6-month fish-based diet, 21 patients (primarily CAD patients) sequentially received high purity EPA (1800mg/day) for 6 months. It resulted in marked increment of plasma EPA/AA ratio (0.65±0.57 vs. 1.19±0.46, p<0.001), accompanied by significant reduction in baPWV (1968±344cm/s vs. 1829±344cm/s, p=0.0061). There was a significant negative correlation between changes in baPWV and changes in plasma EPA/AA ratio in patients with a fish-based diet and sequential administration of EPA (r=−0.446, p=0.017). ConclusionA fish-based diet was effective against increased baPWV only in low-risk patients, with slight increment of plasma EPA/AA. In high-risk patients and CAD patients, administration of EPA for preventing progression of baPWV endorsed the validity of high purity EPA administration recommended in the current guidelines.

Abstract 73: Use of an ED- Based Observation Unit Followed by Outpatient Stress Testing in Chest Pain Patients with Prior Coronary Artery Disease History: Evaluation of Safety and Prognostic Utility

Objective: Chest pain (CP) observation units are increasingly being used to efficiently triage patients with CP but without high-risk features such as positive biomarkers or pathologic ECG changes. However, little data is available regarding the use of a CP observation strategy in patients presenting with low-risk CP but with history of prior CAD events. The aim of the present study was to determine the outcomes of patients with CP and established CAD managed with observation followed by outpatient stress myocardial perfusion imaging (MPI) and to determine the prognostic value of this strategy. Methods: Retrospective analysis of patients with CP managed with observation followed by outpatient stress MPI at a single community teaching hospital and followed up for 3 years for CV events (defined as death, MI, or need for urgent revascularization). Follow-up event rates were stratified by CAD history at the time of initial CP evaluation. Results: A total of 375 patients were included: 111 with and 264 without a CAD history. All patients safely completed outpatient stress MPI within 72 hours of observation. Stress MPI effectively identified patients at risk for CV events regardless of CAD history, although patients with CAD history had a significantly higher rate of +MPI (35/111 (31.5%) vs. 28/264 (10.6%) for patients with +CAD vs. [[Unable to Display Character: &amp;#8211;]]CAD history, respectively, p=&lt;0.001). Patients managed in an observation unit followed by a non-ischemic outpatient stress MPI and without a CAD history had, as expected, very low rates of short- and long-term CAD events (2/264 (0.8%), and 3/264 (1.1%) at 1 year and 3 years, respectively). In contrast, follow-up event rates of those patients with a non-ischemic test but a +CAD history were significantly higher (6/111 (5.4%) and 7/111 (6.3%) at 1 year and 3 years, respectively; p=0.044 and p=0.034 compared to CAD- patients). To determine if stress MPI testing contributed independent prognostic information regarding CP patients with a history of CAD, we developed a multivariable logistic regression model using patient demographic and risk factor data as well as MPI results: in this model a positive MPI proved to be a strong independent predictor of long-term CV events (OR=4.75 for CV events at 3yr follow-up, 95% CI 1.35-16.70, p=0.015). Conclusion: A strategy of observation followed by stress MPI can safely and effectively risk stratify CP patients with prior CAD for long-term CV events. However, our data suggests these patients are at increased risk of CV events even after a low-risk follow-up stress MPI study. Thus, patients presenting with CP and managed with a strategy of observation and a non-ischemic stress MPI still warrant close short and long term monitoring for recurrent events.

Does Motor Dysfunction After Cerebral Infarction Impede the Development of Angina Symptoms?

Previous studies based on coronary angiography or computed tomography coronary angiography have demonstrated a high prevalence of coronary stenosis in patients with cerebral infarction and no prior history of coronary artery disease (CAD). The purpose of the present study was to compare the coronary angiographic findings of patients with prior cerebral infarction with those of patients with no prior cerebral infarction. Consecutive patients (n = 126) who underwent a first coronary angiography for suspected CAD but had no prior history of CAD were classified into 2 groups, those with a clinical history of cerebral infarction (cerebral infarction group) and those without a clinical history of cerebral infarction (noncerebral infarction group). The incidences of diabetes mellitus, peripheral artery disease, coronary stenosis, and multivessel disease were significantly higher in the cerebral infarction group than in the noncerebral infarction group. Multiple logistic regression analysis relating to coronary stenosis identifi ed prior cerebral infarction (P = 0.0027, odds ratio = 4.414) and diabetes mellitus (P = 0.0446, odds ratio = 2.619) as explanatory factors. Thirty-four of 78 patients (44%) with coronary stenosis did not have angina symptoms. Multiple logistic regression analysis regarding the lack of angina symptoms identified motor dysfunction (modified Rankin scale ≥ 2) (P = 0.0028, odds ratio = 8.323) as an explanatory factor. The results of the present study suggest that compared with patients without cerebral infarction those with the disorder have a high prevalence of coronary stenosis, and indicate that the development of angina symptoms is influenced by the severity of motor dysfunction.

ABCA1 gene promoter DNA methylation is associated with HDL particle profile and coronary artery disease in familial hypercholesterolemia

High-density lipoproteins cholesterol (HDL-C) level, a strong coronary artery disease (CAD) clinical biomarker, shows significant interindividual variability. However, the molecular mechanisms involved remain mostly unknown. ATP-binding cassette A1 (ABCA1) catalyzes the cholesterol transfer from peripheral cells to nascent HDL particles. Recently, a differentially methylation region was identified in ABCA1 gene promoter locus, near the first exon. Therefore, we hypothesized that DNA methylation changes at ABCA1 gene locus is one of the molecular mechanisms involved in HDL-C interindividual variability. The study was conducted in familial hypercholesterolemia (FH), a monogenic disorder associated with a high risk of CAD . Ninety-seven FH patients (all p.W66G for the LDLR gene mutation and not under lipid-lowering treatment) were recruited and finely phenotyped for DNA methylation analyses at ABCA1 gene locus. ABCA1 DNA methylation levels were found negatively correlated with circulating HDL-C (r = -0.20; p = 0.05), HDL2-phospholipid levels (r = -0.43; p = 0.04), and with a trend for association with HDL peak particle size (r = -0.38; p = 0.08). ABCA1 DNA methylation levels were also found associated with prior history of CAD (CAD = 40.2% vs. without CAD = 34.3%; p = 0.003). These results suggest that epigenetic changes within the ABCA1 gene promoter contribute to the interindividual variability in plasma HDL-C concentrations and are associated with CAD expression. These findings could change our understanding of the molecular mechanisms involved in the pathophysiological processes leading to CAD.

Computed Tomography Coronary Angiography as Initial Work-Up for Unstable Angina Pectoris

Computed Tomography Coronary Angiography (CTCA) is a rapid, non-invasive diagnostic tool for coronary artery disease (CAD). Rapid Access Chest Pain Clinics (RACPC) were introduced in UK in 2000, in order to assess rapidly patients with chest pain. To evaluate the use of CTCA as initial work-up for unstable angina pectoris in a primary care-based RACPC. Eighty-eight (n=88) patients were examined by a consultant cardiologist and referred for CTCA if indicated. CTCA was performed with a 640 slices, 320-row CT scanner. Thirty-five (n=35) patients were discharged without further investigations; 50 (mean age 59.8 years; 24 male) were referred for CTCA and 3 were referred directly for an invasive angiography (IA). Following CTCA, 17 patients were discharged. Seventeen (n=17) patients with no history of CAD, but with positive CTCA findings and eleven (n=11) patients with known CAD but without new lesions on CTCA were discharged after optimisation of medical treatment. Five (n=5) of the 50 patients eventually underwent IA; 2 were referred for CABG; 3 continued with medical treatment. No major adverse cardiac events were recorded in a 6-months’ follow up period. The cost for each patient who underwent CTCA was £1,087; 94% of patients rated their experience as good or excellent. The time interval from RACPC visit-to-definitive diagnosis was <3 weeks in 50% of patients, <6 weeks in 90%. Use of CTCA as initial investigation in Primary Care, is both clinically and cost-effective. CTCA should be considered in the initial diagnostic work-up of unstable angina pectoris patients, with or without prior history of CAD.

Prognostic value of cardiovascular CT: Is coronary artery calcium screening enough? The added value of CCTA

Coronary artery disease (CAD) is the primary cause of death in adults in the United States. Only 50% of patients who present with a myocardial infarction have a prior history of CAD. Non-invasive cardiac imaging tests have been developed to diagnose CAD. Current guidelines and systematic reviews have tried to determine the prognostic value of the coronary artery calcium (CAC) scoring and the coronary computed tomography angiography (CCTA) for major adverse cardiovascular events. Several studies support the roles of CCTA and CAC scoring for the diagnosis of CAD in asymptomatic patients. Further studies are needed to confirm the superior role of CCTA over CAC scoring in symptomatic patients.

Abstract P107: Diagnostic Accuracy of Coronary Artery Stenosis With 64-Multidetector Row Coronary Computed Tomographic Angiography in Veteran Patients Presenting With Chest Pain

Background: The ACCURACY trial was a prospective multicenter study using 64-multidetector row coronary computed tomographic angiography (CCTA) to evaluate its diagnostic performance for the detection and exclusion of coronary artery stenosis in patients presenting with chest pain without known coronary artery disease (CAD). We evaluated patients at a Veterans Administration Hospital (VAH) to assess if CCTA possesses high diagnostic accuracy for detection of obstructive CAD at both thresholds of 50% and 70% stenosis compared to invasive coronary angiography (ICA). Methods: We conducted a retrospective study of 44 patients at a VAH from November 2008 to November 2009. Baseline demographics are noted in Table 1 . Inclusion criteria were: age ≥ 21, no known history of CAD, and symptoms of typical or atypical chest pain. All patients underwent CCTA and subsequently had ICA performed within 1 month. CCTAs and ICAs were evaluated and scored for coronary stenosis by 2 independent blinded readers. A vessel based analysis was used to evaluate for ≥ 50% and ≥ 70% stenosis using a 15 segment American Heart Association coronary tree model. Results: A total of 176 vessels were analyzed. Compared to ICA, CCTA's sensitivity, specificity, positive predictive value, and negative predictive value (NPV) for detecting greater than 50% stenoses were, 85%, 89%, 54% and 98%, respectively, and 86%, 91%, 51%, 98%, respectively, for stenoses greater than 70%. There were no statistically significant differences for sensitivity, specificity or NPV compared to the findings in the ACCURACY trial. Conclusion: Among veteran patients presenting with chest pain and no prior history of CAD, CCTA appears to be an effective noninvasive alternative to exclude coronary artery stenosis. Table 1: Baseline Demographics Risk Factors ACCURACY Trial VHA patients p-value Age 57 ± 10 61 ± 9.9 0.016 Sex Male gender 59% 95% p &lt; 0.001 Race Caucasian African American Hispanic Other 87.8% 5.7% 3.5% 3.1% 86% 6.3% 3.8% 3.9% NS Body mass index (kg/m²) 31.4 ± 6.2 29.9 ± 6.1 NS Heart rate (beats/min) 60 ± 12 63.2 ± 9.2 NS Creatinine (mg/dl) 1.0 ± 0.2 0.97 ± 0.19 NS Agatston coronary artery calcium score 284 ± 538 916 ± 805 p &lt; 0.001 Diabetes 23.9% 21.6% NS Hypertension 67% 64% NS Hyperlipidemia 68.3% 66% NS Family History of coronary artery disease 73.5% 71.2% NS Smoker 55.7% 53.2% NS

Increased volume of epicardial fat is an independent risk factor for accelerated progression of sub-clinical coronary atherosclerosis

BackgroundEpicardial 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. MethodsCAC 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 >2.5mm3 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. ResultsBoth 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. ConclusionEAT 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.

Coronary multidetector computed tomographic angiography to evaluate coronary artery disease in liver transplant candidates: methods, feasibility and initial experience

In patients undergoing orthotopic liver transplantation (OLT), coronary artery disease (CAD), obstructive and nonobstructive, is associated with high morbidity and mortality. In OLT candidates, stress testing for detecting ischemia is often inaccurate, and this patient population often has relative contraindications for cardiac catheterization. The objective of this study was to describe the methods, assess the feasibility and determine the extent and severity of CAD in OLT candidates without a prior history of CAD using coronary multidetector computer tomographic angiography (MDCTA). Sixty-five OLT candidates without known CAD underwent coronary MDCTA with dual source cardiac computed tomography (Siemens Definition). Coronary arteries were divided into 17 segments based on American Heart Association guidelines and evaluated independently by two blinded reviewers. Image quality of coronary MDCTA was assessed on a four-point Likert scale (0 = poor, 1 = fair, 2 = good, and 3 = excellent). Atherosclerotic lesions were evaluated for severity [mild (0-50%), moderate (51-70%), and severe (71-100%)], morphology, extent, location and consistency. Image quality was graded as good or excellent in 73.8%. In this cohort of OLT candidates without known CAD, 9% had normal coronary arteries, 58% had mild CAD and 34% had moderate to severe CAD. Plaque severity and burden scores were high. The prevalence of asymptomatic CAD is high in OLT candidates. Coronary MDCTA is feasible in OLT candidates and appears to be a useful technique to diagnose occult CAD in this patient population.

Treadmill Exercise Stress Echocardiography in Patients With No History of Coronary Artery Disease: A Single-Center Experience in Korean Population

Background and ObjectivesTreadmill exercise stress echocardiography (TSE) has superior diagnostic accuracy than exercise electrocardiography (ECG). The objectives of the study are 1) to define the diagnostic accuracy and safety of TSE in patients without a history of coronary artery disease (CAD), 2) to identify the clinical characteristics that predict positive TSE results and 3) to assess the differential predictive value between TSE and concomitant exercise ECG in a Korean population.Subjects and MethodsA total of 1,287 patients among 1,500 consecutive patients with no prior history of CAD and who were referred for TSE during a 4-year 3-month period were enrolled.ResultsOf the 1,287 patients, 95 (7.4%) showed positive TSE results (newly developed regional wall motion abnormality). Among the 154 patients with coronary angiography, 94 patients (61%) showed significant CAD (30 of 77 patients with negative TSE results and 64 of 77 patients with positive TSE results). The TSE positive population had more cardiovascular risk factors and showed a higher Duke treadmill score and wall motion score index than the TSE negative group. TSE showed relatively good sensitivity (68%), specificity (78%) and positive and negative predictive values (83% and 61%, respectively), and TSE also had higher diagnostic accuracy than concomitant exercise ECG (72% vs. 64%, respectively).ConclusionTSE is safe and offers greater diagnostic power for CAD than exercise ECG in Korean population without a history of CAD. Its prognostic value in this population needs to be confirmed in a larger prospective study.

Prevalence of Asymptomatic Coronary Artery Disease in Ischemic Stroke Patients

Coronary artery disease (CAD) is a significant cause of morbidity and mortality in stroke patients. Some patients with asymptomatic CAD might benefit from specific prevention, but the prevalence of asymptomatic CAD is not well known. We assessed the prevalence of >or=50% asymptomatic CAD in patients with ischemic stroke or transient ischemic attack and whether the prevalence is related to traditional vascular risk factors and cervicocephalic atherosclerosis. From January 2006 to February 2009, consecutive patients between 45 and 75 years of age with nondisabling, noncardioembolic ischemic stroke or transient ischemic attack and no prior history of CAD were enrolled in the study. All patients had a 64-section computed tomography coronary angiography and a detailed cervicocephalic arterial workup. Risk factors were assessed individually and through the Framingham Risk Score. Among 300 patients included in the study, 274 had computed tomography coronary angiography. The prevalence of >or=50% asymptomatic CAD was 18% (95% confidence interval [CI], 14 to 23; n=50). Asymptomatic CAD was independently associated with traditional risk factors assessed individually and through the Framingham Risk Score (odds ratio [OR], 2.6; 95% CI, 1.0 to 7.6 for a 10-year risk of coronary heart disease of 10% to 19%; and OR, 7.3; 95% CI, 2.8 to 19.1 for a 10 year-risk of coronary heart disease >or=20%), the presence of at least 1 >or=50% cervicocephalic artery stenosis (OR, 4.0; 95% CI, 1.4 to 11.2), excessive alcohol consumption (OR, 3.1; 95% CI 1.3 to 7.3), and ankle brachial index <0.9 (OR, 2.2; 95% CI, 0.9 to 5.2). The prevalence of >or=50% asymptomatic CAD was also related to the extent of cervicocephalic atherosclerosis. About one fifth of patients with nondisabling, noncardioembolic ischemic stroke or transient ischemic attack have >or=50% asymptomatic CAD. In addition to vascular risk factors, the presence of >or=50% cervicocephalic artery stenosis is strongly related to >or=50% asymptomatic CAD.

Relation of coronary artery plaque location to extent of coronary artery disease studied by computed tomographic angiography

Distal coronary artery disease (CAD) is less amenable to surgery or stenting compared with proximal disease. However, little is known about the epidemiology of distal versus proximal CAD. We determined the prevalence and factors associated with proximal, mid, and distally located plaque in the left anterior descending, left circumflex, and right coronary arteries in 418 subjects without prior CAD history who underwent coronary computed tomographic angiography for symptoms or stress test results. Clinical characteristics and coronary artery calcium (CAC) scores were also determined. Most subjects (88%) had plaque, but only 18% of plaques were associated with stenosis >50%. In subjects with single-vessel plaque, only 7% had distal plaque, whereas 75% had proximal plaque. With 3-vessel plaque, 70% had distal and 100% had proximal plaques. Of subjects with a single location of plaque along a vessel, most had proximal plaque (69%); isolated distal-vessel plaque was rare (2%). Distal plaque was dominantly found in association with both proximal and mid plaque (88%). After multivariable adjustment for demographics, traditional, and nontraditional risk factors, both increasing number of vessels with plaque and clinically significant CAC scores were independently associated with higher odds of distal plaque, whereas associations of traditional risk factors were weaker. Distal plaque was independently associated with stenosis > 50%. These data support the concept that early lesions are most often proximal and that CAC scoring may be a poor screening tool for detecting proximal disease. Furthermore, distal lesions are more associated with advanced disease than with traditional cardiovascular risk factors.