Intermediate Risk Of Coronary Artery Disease Research Articles

How did the COVID-19 pandemic affect the referral patterns for SPECT myocardial perfusion? A single center experience.

We evaluated the impact of the COVID-19 pandemic on the number of referrals for SPECT myocardial perfusion imaging (SPECT-MPI) as well as changes in the clinical and imaging characteristics. We respectively reviewed 1042 SPECT-MPI cases performed in a 4-month period during the COVID-19 pandemic (PAN; n=423) and compared their findings with those acquired in the same months before the pandemic (PRE; n=619). The number of stress SPECT-MPI studies performed during the PAN period significantly dropped compared to the number of studies carried out in the PRE period (p = 0.014). In the PRE period, the rates of patients presenting with non-anginal, atypical and typical chest pain were 31%, 25% and 19%, respectively. The figures significantly changed in the PAN period to 19%, 42%, and 11%, respectively (all p-values <0.001). Regarding the pretest probability of coronary artery disease (CAD), a significant decrease and increase were noticed in patients with high and intermediate pretest probability, respectively (PRE: 18% and 55%, PAN: 6% and 65%, p <0.001 and 0.008, respectively). Neither the rates of myocardial ischemia nor infarction differed significantly in the PRE vs. PAN study periods. The number of referrals dropped significantly in the PAN era. While the proportion of patients with intermediate risk for CAD being referred for SPECT-MPI increased, those with high pretest probability were less frequently referred. Image parameters were mostly comparable between the study groups in the PRE and PAN periods.

Ischemic heart disease : More than just chronic CAD

Myocardial ischemia as a reduction in perfusion with therefore oxygen deficiency of vital cardiomyocytes. Thus primary and secondary prophylaxis of myocardial infarction and it's complications. Adenosine-regadenoson stress magnetic resonance imaging (AR-stress MRI), computed tomography coronary angiography (CTCA). Non-invasive stress testing using AR-stress MRI to exclude relevant obstructive coronary artery disease (CAD). Meta-analysis: The diagnosis of obstructive CAD at the coronary artery level has apooled sensitivity of 87.7% and a specificity of 88.6%. Diagnostic accuracy is better than single photon emission computed tomography (SPECT; AUC 0.89 vs. 0.74). AR-stress MRI can be used to assess myocardial ischemia in the setting of obstructive CAD. Current clinical guidelines for myocardial revascularization have strengthened the use of stress MRI in patients with intermediate risk of CAD and stable symptoms. Cardiac MR imaging using late gadolinium enhancement (LGE) is considered gold standard for myocardial viability assessment in vivo. Both viability and ischemia are considered prognostic factors for major adverse cardiac events. AR-stress MRI is used to diagnose myocardial ischemia in combination with viability imaging (LGE). Dobutamine-atropine (DoA) stress MRI is an alternative in the setting of contraindications for AR or specific clinical questions.

Diagnostic accuracy and reclassification potential of the acoustic CADScor algorithm in intermediate risk patients with suspected coronary artery disease

Abstract Background Validation studies of the 2019 European Society of Cardiology pre-test probability model (ESC-PTP) for coronary artery disease (CAD) report that 35–40% of patients have intermediate pre-test risk (ESC-PTP 5-&amp;lt;15%). A clear strategy for deferral or referral in this group has not been established. Stratification tools with a high negative predictive value (NPV) are especially wanted to improve pre-test risk estimates. Acoustic detections of coronary stenosis are a new technology which could potentially be useful to supplement PTP stratification. One of the devices, the CADScor®System, has been shown to down-classify &amp;gt;40% of patients to low risk without increasing CAD prevalence. However, the clinical utility of using the CADScor algorithm (version (V)3.1) has not be validated. Purpose 1) To validate the diagnostic performance of the CADScor®System (V3.1), and 2) to study the reclassification potential of a clinical likelihood strategy by ESC-PTP estimation supplemented by a CAD-score. Methods In total, 1732 patients without known CAD but with symptoms suggestive hereof underwent coronary CTA as a first-line diagnostic test. Based on an interview prior to coronary CTA, the ESC-PTP model was applied and sound recordings were performed using the acoustic CADScor® System. Patients with a suspected &amp;gt;50% diameter stenosis in any coronary segment at coronary CTA were referred to investigation with Invasive angiography (ICA) with measurement of Fractional flow reserve (FFR). The ESC-PTP risk estimation was divided according to the recommended cut-offs of &amp;lt;5%, 5-&amp;lt;15% and &amp;gt;15% PTP of obstructive CAD. Haemodynamically obstructive CAD was defined as: (1) FFR value &amp;lt;0.80, (2) luminal diameter stenosis reduction &amp;gt;90%, or (3) luminal diameter stenosis reduction ≥50% if FFR was indicated but not performed. A predefined cut-off value of 20 was used for CAD-score values to rule-out CAD. Results A suspected stenosis was found in 439 patients (26%) after coronary CTA. The follow up with ICA with FFR showed significant stenoses in 198 patients (12%). In the entire cohort using the ≤20 CAD-score cutoff for CAD rule-out, sensitivity was 85.3% (95% CI 79.5–89.9%), specificity was 40.3% (95% CI 37.8–42.9%), the PPV was 5.9% (95% CI 13.8–18.3%)), and the NPV was 95.4% (95% CI 93.4–96.9%). Hence, the disease prevalence of obstructive CAD was 4.6% in the ruled-out patients. Applying the ≤20 CAD-score cutoff for CAD rule-out in intermediate risk patients (ESC-PTP 5-&amp;lt;15%) a total of 316 patients (48%) were down-classified to low risk with an obstructive CAD prevalence of 3.5%. Conclusion Having high NPV, the CADscor holds excellent rule-out power. Interestingly, the CADscor has reclassification properties in intermediate CAD risk patients where almost 50% can be deferred form further testing without increasing obstructive CAD risk. Thus, the CADscor can supplement clinical assessment to guide decisions on the need for further testing. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): The study was supported by the Health Research Fund of Central Denmark Region, Aarhus University Research foundation and by an institutional research grant from Acarix A/S, Denmark. Patient flowReclassification potential

MONOCYTE SUBSETS HETEROGENEITY AND CORONARY ATHEROSCLEROSIS IN SOUTH ASIANS COMPARED TO WHITE CAUCASIANS

BACKGROUND South Asians (SAs) have an increased prevalence of coronary artery disease (CAD) and myocardial infarction compared with age- and sex-adjusted White Caucasians (WCs). The mechanism for this increased risk is poorly understood. While classical CD14++CD16- monocytes act as independent predictors of cardiovascular disease, differences in the distribution of monocyte subsets between SA and WC have not been established. We aimed to determine if differences exist in monocyte subsets between SAs and WCs at risk for CAD. METHODS AND RESULTS 119 consecutive patients (59 SA, 60 WC) of at least intermediate CAD risk by the INTERHEART score were prospectively enrolled. Patients with history of malignancy, age > 70, GFR < 30 or on dialysis were excluded. A single blood sample was collected for monocyte analysis. Flow cytometry using dual colour fluorescence (CD14, CD16) within the monocyte gate was used to identify monocyte subsets (classical, intermediate, and non-classical) by staff blinded to the individuals’ characteristics. The SA group consisted of 64% males with a mean age of 54 (+/- 9), while the WC group consisted of 55% males with a mean age of 59 (+/- 7). Both groups had similar body mass index, rates of hypertension, dyslipidemia and family history of premature CAD. Compared to WCs, SAs had higher prevalence of diabetes (36% vs. 13%, p = 0.005) and hemoglobin A1C levels (6.0 +/- 1.1% vs. 5.6 +/- 0.6%, p < 0.001). SA patients had a higher proportion (85.3 +/- 10.7% vs. 81.4 +/- 11.0%, p = 0.009) and total level (449.0 +/- 180.4 vs. 388 +/- 127.4, p = 0.010) of classical CD14++CD16- monocytes compared to WCs. There was no difference between the two groups in the proportion of intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes (see Figure 1). There was no association between diabetes and the proportion of monocyte subsets. Ethnicity had a moderate association with the proportion of classical CD14++CD16- monocytes (Eta coefficient = 0.525) with a large effect size (Eta squared = 27.5%). The association of ethnicity with intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes was either weak or negligible with minimal to no effect size (see Table 1). CONCLUSION In patients with substantive risk for CAD, SAs had a significantly higher proportion and level of classical CD14++CD16- monocytes compared to WCs. Our findings provide a novel insight into the potential mechanism of increased CAD susceptibility amongst SAs compared to WCs. South Asians (SAs) have an increased prevalence of coronary artery disease (CAD) and myocardial infarction compared with age- and sex-adjusted White Caucasians (WCs). The mechanism for this increased risk is poorly understood. While classical CD14++CD16- monocytes act as independent predictors of cardiovascular disease, differences in the distribution of monocyte subsets between SA and WC have not been established. We aimed to determine if differences exist in monocyte subsets between SAs and WCs at risk for CAD. 119 consecutive patients (59 SA, 60 WC) of at least intermediate CAD risk by the INTERHEART score were prospectively enrolled. Patients with history of malignancy, age > 70, GFR < 30 or on dialysis were excluded. A single blood sample was collected for monocyte analysis. Flow cytometry using dual colour fluorescence (CD14, CD16) within the monocyte gate was used to identify monocyte subsets (classical, intermediate, and non-classical) by staff blinded to the individuals’ characteristics. The SA group consisted of 64% males with a mean age of 54 (+/- 9), while the WC group consisted of 55% males with a mean age of 59 (+/- 7). Both groups had similar body mass index, rates of hypertension, dyslipidemia and family history of premature CAD. Compared to WCs, SAs had higher prevalence of diabetes (36% vs. 13%, p = 0.005) and hemoglobin A1C levels (6.0 +/- 1.1% vs. 5.6 +/- 0.6%, p < 0.001). SA patients had a higher proportion (85.3 +/- 10.7% vs. 81.4 +/- 11.0%, p = 0.009) and total level (449.0 +/- 180.4 vs. 388 +/- 127.4, p = 0.010) of classical CD14++CD16- monocytes compared to WCs. There was no difference between the two groups in the proportion of intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes (see Figure 1). There was no association between diabetes and the proportion of monocyte subsets. Ethnicity had a moderate association with the proportion of classical CD14++CD16- monocytes (Eta coefficient = 0.525) with a large effect size (Eta squared = 27.5%). The association of ethnicity with intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes was either weak or negligible with minimal to no effect size (see Table 1). In patients with substantive risk for CAD, SAs had a significantly higher proportion and level of classical CD14++CD16- monocytes compared to WCs. Our findings provide a novel insight into the potential mechanism of increased CAD susceptibility amongst SAs compared to WCs.

Multiparametric exercise stress cardiovascular magnetic resonance in the diagnosis of coronary artery disease: the EMPIRE trial

BackgroundStress cardiovascular magnetic resonance (CMR) offers assessment of ventricular function, myocardial perfusion and viability in a single examination to detect coronary artery disease (CAD).We developed an in-scanner exercise stress CMR (ExCMR) protocol using supine cycle ergometer and aimed to examine the diagnostic value of a multiparametric approach in patients with suspected CAD, compared with invasive fractional flow reserve (FFR) as the reference gold standard.MethodsIn this single-centre prospective study, patients who had symptoms of angina and at least one cardiovascular disease risk factor underwent both ExCMR and invasive angiography with FFR. Rest-based left ventricular function (ejection fraction, regional wall motion abnormalities), tissue characteristics and exercise stress-derived (perfusion defects, inducible regional wall motion abnormalities and peak exercise cardiac index percentile-rank) CMR parameters were evaluated in the study.ResultsIn the 60 recruited patients with intermediate CAD risk, 50% had haemodynamically significant CAD based on FFR. Of all the CMR parameters assessed, the late gadolinium enhancement, stress-inducible regional wall motion abnormalities, perfusion defects and peak exercise cardiac index percentile-rank were independently associated with FFR-positive CAD. Indeed, this multiparametric approach offered the highest incremental diagnostic value compared to a clinical risk model (χ2 for the diagnosis of FFR-positive increased from 7.6 to 55.9; P < 0.001) and excellent performance [c-statistic area under the curve 0.97 (95% CI: 0.94–1.00)] in discriminating between FFR-normal and FFR-positive patients.ConclusionThe study demonstrates the clinical potential of using in-scanner multiparametric ExCMR to accurately diagnose CAD.Trial registration: ClinicalTrials.gov, NCT03217227, Registered 11 July 2017–Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03217227?id=NCT03217227&draw=2&rank=1&load=cart

P1218Deep learning survival analysis enhances the value of hybrid PET/CT for long-term cardiovascular event prediction

Abstract Background Deep Learning (DL) is revolutionizing cardiovascular medicine through complex data-pattern recognition. In spite of its success in the diagnosis of coronary artery disease (CAD), DL implementation for prognostic evaluation of cardiovascular events is still limited. Traditional survival models (e.g.Cox) notably incorporate the effect of time-to-event but are unable to exploit complex non-liner dependencies between large numbers of predictors. On the other hand, DL hasn't systematically incorporated time-to-event for prognostic evaluations. Long-term registries of hybrid PET/CT imaging represent a suitable substrate for DL-based survival analysis due the large amount of time-dependent structured variables that they convey. Therefore, we sought to evaluate the feasibility and performance of DL Survival Analysis in predicting the occurrence of myocardial infarction (MI) and death in a long-term registry of cardiac hybrid PET/CT. Methods Data from our PET/CT registry of symptomatic patients with intermediate CAD risk who underwent sequential CT angiography and 15O-water PET for suspected ischemia, was analyzed. The sample has been followed for a 6-year average for MI or death. Ten clinical variables were extracted from electronic records including cardiovascular risk factors, dyspnea and early revascularization. CT angiography images were evaluated segmentally for: presence of plaque, % of luminal stenosis and calcification (58 variables). Absolute stress PET myocardial perfusion data was evaluated globally and regionally across vascular territories (4 variables). Cox-Nnet (a deep survival neural network) was implemented in a 5-fold cross-validated 80:20 split for training and testing. Resulting DL-hazard ratios were operationalized and compared to the observed events developed during follow-up. The performance of Cox-Nnet evaluating structured CT, PET/CT, and PET/CT+clinical variables was compared to expert interpretation (operationalized as: normal coronaries, non-obstructive CAD, obstructive CAD) and to Calcium Score (CaSc), through the concordance (c)-index. Results There were 426 men and 525 women with a mean age of 61±9 years-old. Twenty-four MI and 49 deaths occurred during follow-up (1 month–9.6 years), while 11.5% patients underwent early revascularization. Cox-Nnet evaluation of PET/CT data (c-index=0.75) outperformed categorical expert interpretation (c-index=0.54) and CaSc (c-index=0.65), while hybrid PET/CT and PET/CT+clinical (c-index=0.75) variables demonstrated incremental performance overall independent from early revascularization. Conclusion Deep Learning Survival Analysis is feasible in the evaluation of cardiovascular prognostic data. It might enhance the value of cardiac hybrid PET/CT imaging data for predicting the long-term development of myocardial infarction and death. Further research into the implementation of Deep Learning for prognostic analyses in CAD is warranted.

Sexual Dimorphism of Coronary Artery Disease in a Low- and Intermediate-Risk Asymptomatic Population: Association with Coronary Vessel Wall Thickness at MRI in Women.

To demonstrate the association between coronary vessel wall thickness (VWT) measured at MRI and coronary artery disease (CAD) risk in asymptomatic groups at low and intermediate risk on the basis of Framingham score. A total of 131 asymptomatic adults were prospectively enrolled. All participants underwent CT angiography for scoring CAD, and coronary VWT was measured at 3.0-T MRI. Nonlinear single and multivariable regression analyses with consideration for interaction with sex were performed to investigate the association of traditional atherosclerotic risk factors and VWT with CT angiography-based CAD scores. The analysis included 62 women and 62 men with low or intermediate Framingham score of less than 20%. Age (mean age, 45.0 years ± 14.5 [standard deviation]) and body mass index were not different between the groups. Age, sex, and VWT were individually significantly associated with all CT angiography-based CAD scores (P < .05). Additionally, sex was a significant effect modifier of the associations with all CAD scores. In men, age was the only statistically significant independent risk factor of CAD; in women, VWT was the only statistically significant independent surrogate associated with increased CAD scores (P < .05). In asymptomatic women, VWT MRI was the primary independent surrogate of CAD, whereas age was the strongest risk factor in men. This study suggests that VWT may be used as a CAD surrogate in women at low or intermediate risk of CAD. Further longitudinal studies are required to determine the potential implication and use of this MRI technique for the preventative management of CAD in women.© RSNA, 2019.

Non-invasive fractional flow reserve using computed tomographic angiography: where are we now and where are we going?

### Learning objectives Coronary computed tomographic angiography (CTA) is now established as a clinically valuable non-invasive anatomical test for the detection and exclusion of significant coronary disease. A number of...

An Audit on the Appropriateness of Coronary Computed Tomography Angiography Referrals in a Tertiary Cardiac Center.

Background:In response to growing concerns regarding the overuse of coronary computed tomography angiography (CCTA) in the clinical setting, multiple societies, including the American College of Cardiology Foundation, have jointly published revised criteria regarding the appropriate use of this imaging modality. However, previous research indicates significant discrepancies in the rate of adherence to these guidelines.Aim:To assess the appropriateness of CCTA referrals in a tertiary cardiac center in Bahrain.Methods:This retrospective clinical audit examined the records of patients referred to CCTA between the April 1, 2015 and December 31, 2015 in Mohammed bin Khalifa Cardiac Center. Using information from medical records, each case was meticulously audited against guidelines to categorize it as appropriate, inappropriate, or uncertain.Results:Of the 234 records examined, 176 (75.2%) were appropriate, 47 (20.1%) were uncertain, and 11 (4.7%) were inappropriate. About 74.4% of all referrals were to investigate coronary artery disease (CAD). The most common indication that was deemed appropriate was the detection of CAD in the setting of suspected ischemic equivalent in patients with an intermediate pretest probability of CAD (65.9%). Most referrals deemed inappropriate were requested to detect CAD in asymptomatic patients at low or intermediate risk of CAD (63.6%).Conclusion:This audit demonstrates a relatively low rate of inappropriate CCTA referrals, indicating the appropriate and efficient use of this resource in the Mohammed bin Khalifa Cardiac Center. Agreement on and reclassification of “uncertain” cases by guideline authorities would facilitate a deeper understanding of referral appropriateness.

Epicardial Adipose Tissue Is Associated with Plaque Burden and Composition and Provides Incremental Value for the Prediction of Cardiac Outcome. A Clinical Cardiac Computed Tomography Angiography Study.

ObjectivesWe sought to investigate the association of epicardial adipose tissue (eCAT) volume with plaque burden, circulating biomarkers and cardiac outcomes in patients with intermediate risk for coronary artery disease (CAD).Methods and Results177 consecutive outpatients at intermediate risk for CAD and completed biomarker analysis including high-sensitive Troponin T (hs-TnT) and hs-CRP underwent 256-slice cardiac computed tomography angiography (CCTA) between June 2008 and October 2011. Patients with lumen narrowing ≥50% exhibited significantly higher eCAT volume than patients without any CAD or lumen narrowing <50% (median (interquartile range, IQR): 108 (73–167) cm3 vs. 119 (82–196) cm3, p = 0.04). Multivariate regression analysis demonstrated an independent association eCAT volume with plaque burden by number of lesions (R2 = 0.22, rpartial = 0.29, p = 0.026) and CAD severity by lumen narrowing (R2 = 0.22, rpartial = 0.23, p = 0.038) after adjustment for age, diabetes mellitus, hyperlidipemia, body-mass-index (BMI), hs-CRP and hs-TnT. Univariate Cox proportional hazards regression analysis identified a significant association for both increased eCAT volume and maximal lumen narrowing with all cardiac events. Multivariate Cox proportional hazards regression analysis revealed an independent association of increased eCAT volume with all cardiac events after adjustment for age, >3 risk factors, presence of CAD, hs-CRP and hs-TnT.ConclusionEpicardial adipose tissue volume is independently associated with plaque burden and maximum luminal narrowing by CCTA and may serve as an independent predictor for cardiac outcomes in patients at intermediate risk for CAD.

Abstract 180: Variation in the Use of Angiography Between Procedural and Non-procedural Cardiologists

Background: Physician specialty is associated with adherence to practice guidelines; clinical activities may influence management approaches when guidelines create equipoise. In a scenario in which either a non-invasive stress test or invasive angiography is appropriate, we hypothesized that cardiologists who perform cardiac procedures would be more likely to recommend an invasive approach compared to non-procedural cardiologists. Methods: We developed a web-based, email survey with a 2-part standardized patient case. The first part described a patient with symptoms suggestive of obstructive coronary artery disease (CAD) the second part described an abnormal exercise treadmill test (ETT) result in that patient. In both parts, the scenario was designed to represent an intermediate likelihood of obstructive CAD. Providers were asked to rate the likelihood of obstructive CAD and choose between angiography and stress testing for that patient; both a secondary stress and angiography would be consistent with guidelines. Cardiologists were classified based on self-report to non-procedural (general, non-invasive, heart failure/transplant, congenital) or procedural (invasive, interventional, electrophysiology and cardiothoracic surgery) practice. Multivariable models were used to determine the association between procedural practice and referral for angiography controlling for provider factors (age, gender, years in practice, practice setting) and estimated likelihood of CAD for that patient. Results: Of the 500 cardiologists who responded, 41.8% were procedural cardiologists. Procedural cardiologists similarly rated the patient as having a high likelihood for CAD (part 1: 38.8% vs 40.9%, p= 0.63; part 2: 81.8% vs 81.1%, p = 0.84) compared to non-procedural cardiologists. Although for a patient with intermediate risk of CAD by symptoms, more procedural cardiologists recommended direct angiography referral (12% vs 5.6%, p &lt;0.01) than non-procedural cardiologists. In multivariable models, procedural practice remained associated with higher direct angiography referral (OR 2.67; 95% CI 1.30, 5.49, p= 0.008). After an intermediate risk ETT result, both groups recommended angiography more often (70.5% vs 68.2% p=0.58) than secondary stress testing. Conclusions: Procedural cardiologists more often referred a patient with symptoms concerning for CAD directly for angiography compared to non-procedural cardiologists. When presented an abnormal stress test, both groups were equally likely to recommend angiography over additional stress testing. Therefore, clinical activities may influence management approaches; procedural cardiologists pursued an invasive approach earlier in the diagnostic pathway. Efforts to understand variation in invasive procedure use should take physician clinical activities into account.

Carotid intima media thickness and coronary atherosclerosis linkage in symptomatic intermediate risk patients evaluated by coronary computed tomography angiography

BackgroundThere is a growing evidence that carotid intima media thickness (CIMT) is associated with coronary artery disease (CAD) and it should be used as a predictor of atherosclerotic burden of coronary arteries. However, these studies have been performed by using invasive coronary angiography (ICA) and in high-risk patients for CAD. The purpose of this study was to evaluate the correlation between CIMT by ultrasound and coronary atherosclerosis in symptomatic intermediate risk patients by coronary computed tomography angiography (CCTA). MethodsWe enrolled 204 consecutive symptomatic patients (mean age: 61±10; men: 118) and intermediate risk for CAD. All patients underwent CIMT ultrasound evaluation and CCTA. Coronary artery calcium score (CACS), characteristics of plaques, severity of CAD, segment involvement score (SIS) and Gensini's score were assessed and compared with CIMT values. ResultsCIMT has been proved as an independent predictor of a number of coronary artery plaques, overall number of mixed and remodeled plaques, presence of obstructive CAD, high SIS and Gensini's score (HR 1.2, CI 1.05–1.42, p 0.01; HR 1.2, CI 1.01–1.41, p 0.03; HR 9.0, CI 1.37–59.7, p 0.02; HR 21.0, CI 2.40–184, p<0.01; HR 1.2, CI 1.08–1.42, p<0.01; HR 1.2, CI 1.08–1.42, p<0.01, respectively). A cut-off value >1.3 was associated with a better positive and negative predictive value (100% and 69%) to predict the combined endpoint of presence and mixed and/or remodeled coronary artery plaques. ConclusionsCIMT is an independent predictor of coronary atherosclerotic burden as detected by CCTA in symptomatic intermediate risk patients.

Abstract 108: Differences in Cardiologists’ Interpretation and Management of Chest Pain Symptoms and Abnormal Stress Tests in Women and Men

Background: Gender differences in evaluation of coronary artery disease (CAD) have been suggested in observational cohorts. Whether gender differences in care exist under standardized conditions is not well known. Methods: We developed a web-based survey that randomly varied a case vignette by patient gender alone. The first part described a patient presenting with symptoms suggestive of CAD and the second described the results of an abnormal ETT (exercise treadmill test) in that patient. For both parts, the scenario was designed to represent an intermediate likelihood of obstructive CAD regardless of patient gender. Providers were asked to rate the likelihood of obstructive CAD and to choose the best treatment option. The survey was emailed to all physician members of a state cardiology association. A total of 3 reminder emails were sent. Results: Of the 317 cardiologists with valid addresses, 71 (22.4%) completed the survey. Participants were mostly men (82.4%) and non-invasive cardiologists (63%). For both parts of the vignette, cardiologists tended to estimate the likelihood of obstructive CAD as “high” more often when the patient was a man (Table). Respondents were equally likely to recommend cardiac testing based on symptoms suggestive of CAD regardless of patient gender; however, after an abnormal ETT, cardiologists were more likely to recommend angiography for male patients and more likely to recommend a second stress test with imaging for female patients (Table). Conclusions: Using a standardized case patient at intermediate risk for CAD, cardiologists tended to estimate the likelihood of CAD as higher and were more likely to recommend cardiac angiography after an abnormal ETT in male patients and more likely to recommend stress testing with imaging for women. Our findings suggest differences in how cardiologists evaluate symptoms and manage abnormal stress test results according to patient gender.

Plasma lipidomic analysis predicts non-calcified coronary artery plaque in asymptomatic patients at intermediate risk of coronary artery disease

The optimal management of asymptomatic subjects at intermediate risk of coronary artery disease (CAD) is often uncertain. Re-stratification to a high- or low-risk category may enable optimization of preventative strategies. Coronary computed tomographic angiography (CCTA) enables a minimally invasive assessment of coronary artery plaque quantity and composition. Non-calcified plaque by CCTA is lipid-rich and more vulnerable to rupture and resultant acute coronary syndromes. The purpose of this study was to determine whether novel approaches to CAD risk stratification, such as plasma lipid profiling, may predict non-calcified plaque burden in intermediate risk subjects. CCTA and several markers of CAD (including plasma lipid profiling, carotid intima-media thickness, aortic pulse wave velocity, and high-sensitivity C-reactive protein) were prospectively performed in 100 asymptomatic patients at intermediate CAD risk according to the Framingham risk score. Segment stenosis scores (SSS) were calculated to evaluate the burden of total, calcified, and non-calcified coronary artery plaque. Non-calcified plaque was observed in 66 subjects and 158 (11%) of 1425 coronary artery segments. Eighteen lipid species demonstrated significant associations with non-calcified plaque burden, but not with total plaque or calcified plaque burden. No other marker of CAD was found to predict coronary artery plaque burden. Plasma lipidomic analysis can predict the burden of non-calcified coronary plaque in asymptomatic subjects at intermediate risk of CAD. Re-stratification of these patients by plasma lipid profiling may enable more appropriate and effective primary prevention management strategies.

Myocardial perfusion imaging in patients with a recent, normal exercise test

To investigate the added value of myocardial perfusion scintigraphy imaging (MPI) in consecutive patients with suspected coronary artery disease (CAD) and a recent, normal exercise electrocardiography (ECG). This study was a retrospective analysis of consecutive patients referred for MPI during a 2-year period from 2006-2007 at one clinic. All eligible patients were suspected of suffering from CAD, and had performed a satisfactory bicycle exercise test (i.e., peak heart rate > 85% of the expected, age-predicted maximum) within 6 mo of referral, their exercise ECG was had no signs of ischemia, there was no exercise-limiting angina, and no cardiac events occurred between the exercise test and referral. The patients subsequently underwent a standard 2-d, stress-rest exercise MPI. Ischemia was defined based on visual scoring supported by quantitative segmental analysis (i.e., sum of stress score > 3). The results of cardiac catheterization were analyzed, and clinical follow up was performed by review of electronic medical files. A total of 56 patients fulfilled the eligibility criteria. Most patients had a low or intermediate ATPIII pre-test risk of CAD (6 patients had a high pre-test risk). The referral exercise test showed a mean Duke score of 5 (range: 2 to 11), which translated to a low post-exercise risk in 66% and intermediate risk in 34%. A total of seven patients were reported with ischemia by MPI. Three of these patients had high ATPIII pre-test risk scores. Six of these seven patients underwent cardiac catheterization, which showed significant stenosis in one patient with a high pre-test risk of CAD, and indeterminate lesions in three patients (two of whom had high pre-test risk scores). With MPI as a gate keeper for catheterization, no significant, epicardial stenosis was observed in any of the 50 patients (0%, 95% confidence interval 0.0 to 7.1) with low to intermediate pre-test risk of CAD and a negative exercise test. No cardiac events occurred in any patients within a median follow up period of > 1200 d. The added diagnostic value of MPI in patients with low or intermediate risk of CAD and a recent, normal exercise test is marginal.

Multiple Vascular Reactivity Measures Improves Our Ability to Predict Underlying Coronary Artery Disease

patients haveNCPmay enhance cardiovascular risk factor management. We used coronary computed tomography angiography (CCTA) to identify NCP in asymptomatic patients at intermediate risk of coronary artery disease (CAD). Furthermore, we utilised lipidomic profiling to determine whether measuring serum lipids could help predict the presence of NCP in these patients. Methods: We performed 64-slice CCTA on 100 prospectively enrolled asymptomatic subjects (86% male, mean age 61± 6 years) at intermediate CAD risk according to the Framingham cardiovascular risk score. Plaque composition was classified as non-calcified, mixed or calcified and the percentage of coronary artery segments containing non-calcified or mixed plaque was determined for each patient. Serum lipid concentrations of more than 300 molecular species in 20 lipid classes were measured using liquid chromatography-mass spectrometry. Results: CCTA identified NCP in 66 patients. Of these patients, 17% of coronary artery segments containedNCP. No lipid class was significantly associated with the presence of NCP. However, the dihydroceramide (p= 0.003) and GM3 ganglioside (p= 0.002) lipid classes were significantly associated with the percentage of segments containingNCP, after adjusting for age, gender, bodymass index and blood pressure. Conclusions:Most patients at intermediate risk of CAD have non-calcified plaque, however, a significant proportion do not. Lipidomic profiling may assist in predicting which patients of this substantial population are likely to have a greater burden of NCP and, thus, require more aggressive cardiovascular risk factor modification. http://dx.doi.org/10.1016/j.hlc.2013.05.105

Une stratégie combinée coroscanner-scintigraphie myocardique peut permettre de réduire avec sécurité le recours à la coronarographie chez les patients ayant un résultat équivoque à l’un des tests

ObjectivesCT-coronary angiography (CTCA) and myocardial perfusion scintigraphy (MPS) have both high negative predictive values in detecting coronary artery disease (CAD) but suboptimal predictive positive values, leading to unnecessary invasive coronary angiography (ICA) in case of equivocal findings. Combining these two tests may obviate their inherent limitations. Patients and methodsSixty-seven patients at mostly intermediate risk of CAD were subjected to either CTCA (45 patients) or MPS (22 patients) at first test, followed by the second test because of equivocal results of the first test. A discordant defect between the two tests was considered as false positive, hence likely to exclude CAD, and a concordant defect as true positive, likely to confirm CAD. All patients with concordant defects were referred to subsequent ICA. All patients with discordant defects (except for seven of them who underwent ICA too) were subjected to a mean follow-up of 730±377days. ResultsDiscordant findings between CTCA and MPS were found in 41 patients, from whose 7/7 had no significant stenosis at the invasive angiography and 34/34 had no major cardiac event during follow-up. Concordant findings were found in 26 patients. Invasive coronary angiography revealed significant stenoses in 14/26 patients; 9/14 of them needed revascularization. ConclusionA strategy combining CTCA and MPS may safely reduce referral to ICA in patients with equivocal findings at a single examination.

Role of coronary angiography MDCT in the clinical setting: changes in diagnostic workup in the real world

The authors sought to evaluate the incremental value of introducing coronary angiography with multidetector computed tomography (MDCT-CA) compared with the conventional diagnostic workup in managing patients with suspected coronary artery disease (CAD) workup. A total of 531 consecutive patients underwent MDCT-CA between April 2008 and August 2010. For each patient the pretest probability of CAD was obtained by using the Morise score as well as the diagnostic performance of the exercise test and of MDCT-CA, considering conventional coronary angiography (CCA) as the gold standard. Based on these results, we calculated the posttest likelihood of CAD after stress testing, comparing the incremental diagnostic value for each category of cardiovascular risk with data obtained with MDCT-CA. The conventional diagnostic workup (without MDCT-CA) was then compared with the modified workup (including MDCT-CA). The diagnostic performance of the exercise test for identifying patients with significant lesions had a sensitivity and specificity of 20% and 88%, respectively, with positive (PPV) and negative (NPV) predictive value of 41% and 72%, respectively. Taking CA as the gold standard, MDCT-CA had 93% sensitivity, 89% specificity, 88% PPV and 93% NPV compared with CCA in evaluating significant stenoses in the per-patient analysis. The overall diagnostic accuracy of MDCT-CA was 91%. The exercise tests provided no significant incremental diagnostic value compared with cardiovascular history in patients with a low to intermediate risk. Comparison of the diagnostic accuracy of these protocols showed improved performance results for the modified protocol. MDCT-CA is the reference modality for the noninvasive exclusion of critical CAD. It provides a very high incremental diagnostic value compared with exercise testing in patients with a low to intermediate risk of CAD. The use of diagnostic protocols based on MDCT-CA ensures improved diagnostic performance compared with those involving conventional exercise electrocardiograms.

Accuracy of 64-multidetector computed tomography coronary angiography in patients with symptomatic atrial fibrillation prior to pulmonary vein isolation

Aim of our study was to investigate the value of multidetector computed tomography (MDCT) for detecting significant stenoses of coronary arteries in patients with symptomatic atrial fibrillation (AF) prior to pulmonary vein (PV) ablation (PVA). Many patients undergoing PVA for AF receive three-dimensional computed tomography or magnetic resonance tomography imaging for improving anatomical orientation. One-hundred and eighty-one patients with AF refractory to antiarrhythmic treatment underwent ECG-gated 64-MDCT for identification of PV anatomy and simultaneous assessment of coronary vessels before PVA. No additional radiation was incurred for MDCT coronary angiography during MDCT scan. Pretest probability for obstructive coronary artery disease (CAD) was estimated. Invasive coronary angiography (ICA) was performed in all patients with at least intermediate risk of CAD. Eighty-six out of 181 patients (48%) had ICA and MDCT, 95 patients (52%) underwent MDCT alone. ICA revealed significant stenoses in 9% of the catheterized patients (8/86). MDCT investigation lead to a sensitivity of 90% (9/10), specificity of 98% (829/844 lesions), positive predictive value (PPV) of 39% (9/24), and negative predictive value (NPV) of 100% (829/830 lesions) for the detection of >50% stenoses seen on ICA. All patients with a significant stenosis were classified as patients with CAD. Overall prevalence of significant CAD detected by MDCT was found to be low with 10% of patients and 2% of all segments. MDCT coronary angiography is sensitive and highly specific in patients presenting for PVA. In this group a negative scan reliably excludes significant CAD. These data suggest that MDCT coronary angiography can replace ICA prior to PVA.

Prognostic value of coronary artery calcium score and coronary CT angiography in patients with intermediate risk of coronary artery disease

The aim of this study was to compare the prognostic value of coronary calcium scoring and coronary computed tomography (CT) angiography in assessing the cardiac risk and its temporal characteristics in patients at intermediate pre-test likelihood of coronary artery disease (CAD). Cardiac CT was performed in 326 patients at intermediate (15-85%) pre-test likelihood of CAD to evaluate calcium score and presence and severity of the disease. Patients were followed-up for the occurrence of major cardiac events (cardiac death, myocardial infarction, and unstable angina requiring revascularization). During follow-up (26 ± 12 months) 34 events occurred. Calcium score, extent of CAD, and plaque extent and distribution were higher (all P < 0.001) in patients with events than in those without. No patients with calcium score of 0 had events at follow-up. Calcium score (P < 0.001), number of segments with non-calcified or mixed plaque (P < 0.05), and segments-at-risk-score (P < 0.005) were independent predictors of events. Cardiac risk was greater for all time intervals and accelerated more over time with worsening of calcium score. In presence of coronary calcium, significant CAD further increased the probability of failure for all time intervals. Therefore, patients at intermediate CAD risk without coronary calcium do not need further evaluation with longer and higher-radiation-dose protocols, while in the presence of coronary calcium CT angiography is useful to further stratify patients.