Prognostic Significance of Nonobstructive Left Main Coronary Artery Disease in Patients With and Without Diabetes: Long-Term Outcomes From the CONFIRM Registry.

BACKGROUND: Prognostic significance of non-obstructive left main (LM) disease was recently reported. However, the influence of diabetes mellitus (DM) on event rates in patients with and without non-obstructive LM disease is not well-known. METHODS: We evaluated 27,252 patients undergoing coronary computed tomographic angiography from the COroNary CT Angiography Evaluation For Clinical Outcomes: An InteRnational Multicenter (CONFIRM) Registry. Cumulative long-term incidence of all-cause mortality (ACM) was assessed between DM and non-DM patients by normal or non-obstructive LM disease (1-49% stenosis). RESULTS: The mean age of the study population was 57.6±12.6 years. Of the 27,252 patients, 4,434 (16%) patients had DM. A total of 899 (3%) deaths occurred during the follow-up of 3.6±1.9. years. Compared to patients with normal LM, those with non-obstructive LM had more pronounced overall coronary atherosclerosis and more cardiovascular risk factors. After clinical risk factors, segment involvement score, and stenosis severity adjustment, compared to patients without DM and normal LM, patients with DM were associated with increased ACM regardless of normal (HR 1.48, 95% CI 1.22-1.78, p<0.001) or non-obstructive LM (HR 1.46, 95% CI 1.04-2.04, p=0.029), while nonobstructive LM disease was not associated with increased ACM in patients without DM (HR 0.85, 95% CI 0.67-1.07, p=0.165) and there was no significant interaction between DM and LM status (HR 1.03, 95% CI 0.69-1.54, p=0.879). CONCLUSION: From the CONFIRM registry, we demonstrated that DM was associated with increased ACM. However, the presence of non-obstructive LM was not an independent risk marker of ACM, and there was no significant interaction between DM and non-obstructive LM disease for ACM.

Machine learning of clinical variables and coronary artery calcium scoring for the prediction of obstructive coronary artery disease on coronary computed tomography angiography: analysis from the CONFIRM registry.

AIMS: Symptom-based pretest probability scores that estimate the likelihood of obstructive coronary artery disease (CAD) in stable chest pain have moderate accuracy. We sought to develop a machine learning (ML) model, utilizing clinical factors and the coronary artery calcium score (CACS), to predict the presence of obstructive CAD on coronary computed tomography angiography (CCTA). METHODS AND RESULTS: The study screened 35 281 participants enrolled in the CONFIRM registry, who underwent ≥64 detector row CCTA evaluation because of either suspected or previously established CAD. A boosted ensemble algorithm (XGBoost) was used, with data split into a training set (80%) on which 10-fold cross-validation was done and a test set (20%). Performance was assessed of the (1) ML model (using 25 clinical and demographic features), (2) ML + CACS, (3) CAD consortium clinical score, (4) CAD consortium clinical score + CACS, and (5) updated Diamond-Forrester (UDF) score. The study population comprised of 13 054 patients, of whom 2380 (18.2%) had obstructive CAD (≥50% stenosis). Machine learning with CACS produced the best performance [area under the curve (AUC) of 0.881] compared with ML alone (AUC of 0.773), CAD consortium clinical score (AUC of 0.734), and with CACS (AUC of 0.866) and UDF (AUC of 0.682), P < 0.05 for all comparisons. CACS, age, and gender were the highest ranking features. CONCLUSION: A ML model incorporating clinical features in addition to CACS can accurately estimate the pretest likelihood of obstructive CAD on CCTA. In clinical practice, the utilization of such an approach could improve risk stratification and help guide downstream management.

Prognostic value of age adjusted segment involvement score as measured by coronary computed tomography: a potential marker of vascular age.

Extent of coronary atherosclerotic disease (CAD) burden on coronary computed tomography angiography (CCTA) as measured by segment involvement score (SIS) has a prognostic value. We sought to investigate the incremental prognostic value of 'age adjusted SIS' (aSIS), which may be a marker of premature atherosclerosis and vascular age. Consecutive patients were prospectively enrolled into the CONFIRM (Coronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicentre) multinational observational study. Patients were followed for the outcome of all-cause death. aSIS was calculated on CCTA for each patient, and its incremental prognostic value was evaluated. A total of 22,211 patients [mean age 58.5 ± 12.7 years, 55.8% male) with a median follow-up of 27.3 months (IQR 17.8, 35.4)] were identified. After adjustment for clinical factors and presence of obstructive CAD, higher aSIS was associated with increased death on multivariable analysis, with hazard ratio (HR) 2.40 (1.83-3.16, p < 0.001), C-statistic 0.723 (0.700-0.756), net reclassification improvement (NRI) 0.36 (0.26-0.47, p < 0.001), and relative integrated discrimination improvement (IDI) 0.33 (p = 0.009). aSIS had HR 3.48 (2.33-5.18, p < 0.001) for mortality in those without obstructive CAD, compared to HR 1.79 (1.25-2.58, p = 0.02) in those with obstructive CAD. In conclusion, aSIS has an incremental prognostic value to traditional risk factors and obstructive CAD, and may enhance CCTA risk stratification.

Machine learning for prediction of all-cause mortality in patients with suspected coronary artery disease: a 5-year multicentre prospective registry analysis.

AIMS: Traditional prognostic risk assessment in patients undergoing non-invasive imaging is based upon a limited selection of clinical and imaging findings. Machine learning (ML) can consider a greater number and complexity of variables. Therefore, we investigated the feasibility and accuracy of ML to predict 5-year all-cause mortality (ACM) in patients undergoing coronary computed tomographic angiography (CCTA), and compared the performance to existing clinical or CCTA metrics. METHODS AND RESULTS: The analysis included 10 030 patients with suspected coronary artery disease and 5-year follow-up from the COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter registry. All patients underwent CCTA as their standard of care. Twenty-five clinical and 44 CCTA parameters were evaluated, including segment stenosis score (SSS), segment involvement score (SIS), modified Duke index (DI), number of segments with non-calcified, mixed or calcified plaques, age, sex, gender, standard cardiovascular risk factors, and Framingham risk score (FRS). Machine learning involved automated feature selection by information gain ranking, model building with a boosted ensemble algorithm, and 10-fold stratified cross-validation. Seven hundred and forty-five patients died during 5-year follow-up. Machine learning exhibited a higher area-under-curve compared with the FRS or CCTA severity scores alone (SSS, SIS, DI) for predicting all-cause mortality (ML: 0.79 vs. FRS: 0.61, SSS: 0.64, SIS: 0.64, DI: 0.62; P< 0.001). CONCLUSIONS: Machine learning combining clinical and CCTA data was found to predict 5-year ACM significantly better than existing clinical or CCTA metrics alone.

The global cardiovascular magnetic resonance registry (GCMR) of the society for cardiovascular magnetic resonance (SCMR): its goals, rationale, data infrastructure, and current developments.

BACKGROUND: With multifaceted imaging capabilities, cardiovascular magnetic resonance (CMR) is playing a progressively increasing role in the management of various cardiac conditions. A global registry that harmonizes data from international centers, with participation policies that aim to be open and inclusive of all CMR programs, can support future evidence-based growth in CMR. METHODS: The Global CMR Registry (GCMR) was established in 2013 under the auspices of the Society for Cardiovascular Magnetic Resonance (SCMR). The GCMR team has developed a web-based data infrastructure, data use policy and participation agreement, data-harmonizing methods, and site-training tools based on results from an international survey of CMR programs. RESULTS: At present, 17 CMR programs have established a legal agreement to participate in GCMR, amongst them 10 have contributed CMR data, totaling 62,456 studies. There is currently a predominance of CMR centers with more than 10 years of experience (65%), and the majority are located in the United States (63%). The most common clinical indications for CMR have included assessment of cardiomyopathy (21%), myocardial viability (16%), stress CMR perfusion for chest pain syndromes (16%), and evaluation of etiology of arrhythmias or planning of electrophysiological studies (15%) with assessment of cardiomyopathy representing the most rapidly growing indication in the past decade. Most CMR studies involved the use of gadolinium-based contrast media (95%). CONCLUSIONS: We present the goals, mission and vision, infrastructure, preliminary results, and challenges of the GCMR. TRIAL REGISTRATION: Identification number on ClinicalTrials.gov: NCT02806193 . Registered 17 June 2016.

Characteristic Features on Morphologic and Topographic Findings of Pulmonary Vein Orifices in Transition From Diastolic Dysfunction to Heart Failure: A Computerized Tomography Study.

BACKGROUND: Diastolic dysfunction (DD), a precursor to clinical heart failure (HF), has traditionally been evaluated by means of echocardiography. Data regarding morphologic descriptions of pulmonary vein (PV) orifices in transition from DD to HF have been lacking. METHODS AND RESULTS: We retrospectively studied 124 subjects with computerized tomography (CT)-derived PV parameters and echocardiography-derived diastolic indices. We categorized our subjects as 1) non-DD, 2) DD, or 3) heart failure with preserved ejection fraction (HFpEF) and observed a graded enlargement for 4 PV orifice areas across these groups. Positive linear relationship between the 4 PV orifice areas, echocardiography-derived mean pulmonary capillary wedge pressure (PCWP), and velocity of propagation (VP) were observed. Finally, maximum areas of left superior pulmonary vein (LSPV) and left inferior pulmonary vein (LIPV) significantly increased clinical diagnosis of HFpEF (likelihood-ratio χ(2): from 42.92 to 50.75 and 54.67 for LSPV and LIPV, respectively) when superimposed on left ventricular mass index, PCWP, and left atrial volume. CONCLUSIONS: PV size measurements with the use of CT are feasible and further aid in diseases discrimination between preclinical DD and those progressed into HF, even with preserved global pumping. Our data suggest that CT-based PV measures may help to identify subjects at risk for HF.

Volumetric Single-Beat Coronary Computed Tomography Angiography: Relationship of Image Quality, Heart Rate, and Body Mass Index. Initial Patient Experience With a New Computed Tomography Scanner.

BACKGROUND: Cardiac computed tomography (CT) image quality (IQ) is very important for accurate diagnosis. We propose to evaluate IQ expressed as Likert scale, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) from coronary CT angiography images acquired with a new volumetric single-beat CT scanner on consecutive patients and assess the IQ dependence on heart rate (HR) and body mass index (BMI). METHODS: We retrospectively analyzed the data of the first 439 consecutive patients (mean age, 55.13 [SD, 12.1] years; 51.47% male), who underwent noninvasive coronary CT angiography in a new single-beat volumetric CT scanner (Revolution CT) to evaluate chest pain at West Kendall Baptist Hospital. Based on patient BMI (mean, 29.43 [SD, 5.81] kg/m), the kVp (kilovolt potential) value and tube current were adjusted within a range of 80 to 140 kVp and 122 to 720 mA, respectively. Each scan was performed in a single-beat acquisition within 1 cardiac cycle, regardless of the HR. Motion correction software (SnapShot Freeze) was used for correcting motion artifacts in patients with higher HRs. Autogating was used to automatically acquire systolic and diastolic phases for higher HRs with electrocardiographic milliampere dose modulation. Image quality was assessed qualitatively by Likert scale and quantitatively by SNR and CNR for the 4 major vessels right coronary, left main, left anterior descending, and left circumflex arteries on axial and multiplanar reformatted images. Values for Likert scale were as follows: 1, nondiagnostic; 2, poor; 3, good; 4, very good; and 5, excellent. Signal-to-noise ratio and CNR were calculated from the average 2 CT attenuation values within regions of interest placed in the proximal left main and proximal right coronary artery. For contrast comparison, a region of interest was selected from left ventricular wall at midcavity level using a dedicated workstation. We divided patients in 2 groups related to the HR: less than or equal to 70 beats/min (bpm) and greater than 70 bpm and also analyzed them in 2 BMI groupings: BMI less than or equal to 30 kg/m and BMI greater than 30 kg/m. RESULTS: Mean SNR was 8.7 (SD, 3.1) (n = 349) for group with HR 70 bpm or less and 7.7 (SD, 2.4) (n = 78) for group with HR greater than 70 bpm (P = 0.008). Mean CNR was 6.9 (SD, 2.7) (n = 349) for group with HR 70 bpm or less and 5.9 (SD, 2.2) (n = 78) for group with HR 70 bpm or greater (P = 0.002). Mean SNR was 8.8 (SD, 3.2) (n = 249) for group with BMI 30 kg/m or less and 8.1 (SD, 2.6) (n = 176) for group with BMI greater than 30 kg/m (P = 0.008). Mean CNR was 7.0 (SD, 2.8) (n = 249) for group with BMI 30 kg/m or less and 6.4 (SD, 2.4) (n = 176) for group with BMI greater than 30 kg/m (P = 0.002). The results for mean Likert scale values were statistically different, reflecting difference in IQ between people with HR 70 bpm or less and greater than 70 bpm, BMI 30 kg/m or less, and BMI greater than 30 kg/m.

PROMISE of Coronary CT Angiography: Precise and Accurate Diagnosis and Prognosis in Coronary Artery Disease.

Coronary computed tomography angiography (CCTA) is a rapidly growing and powerful diagnostic test that offers a great deal of precision with respect to diagnosing coronary artery disease (CAD). Guideline statements for patients with stable ischemic heart disease have recommended CCTA for only a limited portion of intermediate-risk patients who have relative or absolute contraindications for exercise or vasodilator stress testing. The publication of two large, prospective randomized clinical trials, the Prospective Multicenter Imaging Study for Evaluation of Chest Pain and the Scottish Computed Tomography of the Heart Trial are likely to expand these indications. These new data from large trials, in addition to other studies, show that CCTA is highly sensitive for the detection of CAD, identifies high-risk patients for cardiac events based on extent or plaque morphology of CAD that would not be identified by other noninvasive means, and provides significantly greater diagnostic certainty for proper treatment, including referral for invasive coronary angiography with revascularization more appropriately. Superior diagnostic accuracy and prognostic data with CCTA, when compared with other functional stress tests, may result in a reduction in unnecessary downstream testing and cost savings. In addition, newer CCTA applications hold the promise of providing a complete evaluation of a patient's coronary anatomy as well as a per-vessel ischemic evaluation. This review focuses on the interval knowledge obtained from newer data on CCTA in patients with stable ischemic heart disease, primarily focusing on the contributions of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain and the Scottish Computed Tomography of the Heart Trial.

Incremental prognostic utility of coronary CT angiography for asymptomatic patients based upon extent and severity of coronary artery calcium: results from the COronary CT Angiography EvaluatioN For Clinical Outcomes InteRnational Multicenter (CONFIRM) study.

AIM: Prior evidence observed no predictive utility of coronary CT angiography (CCTA) over the coronary artery calcium score (CACS) and the Framingham risk score (FRS), among asymptomatic individuals. Whether the prognostic value of CCTA differs for asymptomatic patients, when stratified by CACS severity, remains unknown. METHODS AND RESULTS: From a 12-centre, 6-country observational registry, 3217 asymptomatic individuals without known coronary artery disease (CAD) underwent CACS and CCTA. Individuals were categorized by CACS as: 0-10, 11-100, 101-400, 401-1000, >1000. For CCTA analysis, the number of obstructive vessels-as defined by the per-patient presence of a ≥50% luminal stenosis-was used to grade the extent and severity of CAD. The incremental prognostic value of CCTA over and above FRS was measured by the likelihood ratio (LR) χ(2), C-statistic, and continuous net reclassification improvement (NRI) for prediction, discrimination, and reclassification of all-cause mortality and non-fatal myocardial infarction. During a median follow-up of 24 months (25th-75th percentile, 17-30 months), there were 58 composite end-points. The incremental value of CCTA over FRS was demonstrated in individuals with CACS >100 (LRχ(2), 25.34; increment in C-statistic, 0.24; NRI, 0.62, all P < 0.001), but not among those with CACS ≤100 (all P > 0.05). For subgroups with CACS >100, the utility of CCTA for predicting the study end-point was evident among individuals whose CACS ranged from 101 to 400; the observed predictive benefit attenuated with increasing CACS. CONCLUSION: Coronary CT angiography provides incremental prognostic utility for prediction of mortality and non-fatal myocardial infarction for asymptomatic individuals with moderately high CACS, but not for lower or higher CACS.

Qualitative and semi-quantitative evaluation of myocardium perfusion with 3 T stress cardiac MRI.

BACKGROUND: 3 T MRI has been adopted by some centers as the primary choice for assessment of myocardial perfusion over conventional 1.5 T MRI. However, there is no data published on the potential additional value of incorporating semi-quantitative data from 3 T MRI. This study sought to determine the performance of qualitative 3 T stress magnetic resonance myocardial perfusion imaging (3 T-MRMPI) and the potential incremental benefit of using a semi-quantitative perfusion technique in patients with suspected coronary artery disease (CAD). METHODS: Fifty eight patients (41 men; mean age: 59 years) referred for elective diagnostic angiography underwent stress 3 T MRMPI with a 32-channel cardiac receiver coil. The MR protocol included gadolinium-enhanced stress first-pass perfusion (0.56 mg/kg, dipyridamole), rest perfusion, and delayed enhancement (DE). Visual analysis was performed in two steps. Ischemia was defined as a territory with perfusion defect at stress study but no DE or a territory with DE but additional peri-infarcted perfusion defect at stress study. Semi-quantitative analysis was calculated by using the upslope of the signal intensity-time curve during the first pass of contrast medium during dipyridamole stress and at rest. ROC analysis was used to determine the MPRI threshold that maximized sensitivity. Quantitative coronary angiography served as the reference standard with significant stenosis defined as >70 % diameter stenosis. Diagnostic performance was determined on a per-patient and per-vessel basis. RESULTS: Qualitative assessment had an overall sensitivity and specificity for detecting significant stenoses of 77 % and 80 %, respectively. By adding MPRI analysis, in cases with negative qualitative assessment, the overall sensitivity increased to 83 %. The impact of MPRI differed depending on the territory; with the sensitivity for detection of left circumflex (LCx) stenosis improving the most after semi-quantification analysis, (66 % versus 83 %). CONCLUSIONS: Pure qualitative assessment of 3 T MRI had acceptable performance in detecting severe CAD. There is no overall benefit of incorporating semi-quantitative data; however a higher sensitivity can be obtained by adding MPRI, especially in the detection of LCx lesions.

Rest-Only Myocardial CT Perfusion in Acute Chest Pain.

OBJECTIVES: Cardiac computed tomography perfusion (CTP) using stress testing is an emerging application in the field of cardiac computed tomography. We evaluated patients with acute chest pain (CP) in the emergency department (ED) with evidence of obstructive coronary artery disease (CAD), defined as >70% stenosis on coronary computed tomography angiography (CCTA) and confirmed by invasive coronary angiography (ICA), to evaluate the applicability of resting CTP in the acute CP setting. METHODS: From January to December 2013, 183 low-intermediate risk symptomatic patients with negative cardiac biomarkers and no known CAD underwent a rapid CCTA protocol in the ED. Of these, 4 patients (1.4%) had obstructive CAD (≥70% stenosis) on CCTA confirmed by ICA. All 183 CCTA studies were evaluated retrospectively with CTP software by a transmural perfusion ratio (TPR) method with a superimposed 17-segment model. A TPR value <0.99 was considered abnormal based on previously published data. RESULTS: A total of four patients were included in this pilot analysis. The duration from resolution of CP to performance of CCTA ranged from 1.6 to 5.0 hours. Three patients underwent revascularization, two with percutaneous coronary intervention (PCI) and one with coronary artery bypass grafting. The fourth patient was managed with aggressive medical therapy. Two patients had multivessel obstructive CAD and two patients had single-vessel CAD. The first patient underwent CCTA 5 hours after resolution of CP symptoms. CCTA demonstrated noncalcified obstructive CAD in the mid-LAD and mid-right coronary artery. ICA showed good correlation by quantitative coronary assessment (QCA) in both vessels and the patient underwent PCI. CTP analysis demonstrated perfusion defects in the LAD and right coronary artery territories. The second patient underwent CCTA 1.6 hours after resolution of CP symptoms with findings of obstructive ostial left main CAD. ICA confirmed obstructive left main CAD by QCA and intravascular ultrasound. The patient underwent revascularization with coronary artery bypass grafting. CTP demonstrated perfusion defects in the anterior and lateral wall segments. The third patient was evaluated for CP in the ED with CCTA demonstrating single-vessel CAD 10 hours after resolution of symptoms with findings of a noncalcified obstructive stenosis in the mid-LAD. The patient subsequently underwent ICA demonstrating good correlation to the CCTA findings in the LAD by QCA. CTP analysis revealed perfusion defects in LAD territory. He was successful treated with PCI. The final patient underwent CCTA 5.4 hours following resolution of CP with the finding of an intermediate partially calcified stenosis in the distal LAD. ICA was performed, with fractional flow reserve demonstrating a hemodynamically insignificant distal LAD at 0.86. CTP detected a perfusion defect in the LAD territory. CONCLUSIONS: When positive, rest CTP may have value in the risk stratification of patients presenting to the ED with nontraumatic acute CP.

Left ventricular function and volume with coronary CT angiography improves risk stratification and identification of patients at risk for incident mortality: results from 7758 patients in the prospective multinational CONFIRM observational cohort study.

PURPOSE: To assess whether gradations of left ventricular (LV) ejection fraction (LVEF) and volumes measured with coronary computed tomography (CT) would augment risk stratification and discrimination for incident mortality. MATERIALS AND METHODS: This study was approved by the institutional review board, and informed consent was obtained when required. Subjects without known coronary artery disease (CAD) who underwent cardiac CT angiography with quantitative LV measurements were categorized according to LVEF (≥ 55%, 45%-54.9%, 35%-44.9%, or <35%). LV end-systolic volume (LVESV) and LV end-diastolic volume (LVEDV) were classified as normal (≥ 90 mL) or abnormal (≥ 200 mL). CAD extent and severity was categorized as none, nonobstructive, obstructive (≥ 50%), one-vessel, two-vessel, and three-vessel or left main disease. LVEF and volumes were assessed for risk prediction and discrimination of future mortality by using Cox hazards model and receiver operating characteristic curve analysis, respectively. RESULTS: During a follow-up of 2.0 years ± 0.9, 7758 patients (mean age, 58.5 years ± 13.0; 4220 male patients [54.4%]) were studied. At multivariable analysis, worsening LVEF was independently associated with mortality for moderately (hazard ratio = 3.14, P < .001) and severely (hazard ratio = 5.19, P < .001) abnormal ejection fraction. LVEF demonstrated improved discrimination for mortality (Az = 0.816) when compared with CAD risk factors alone (Az = 0.781) or CAD risk factors plus extent and severity. At multivariable analysis of a subgroup of 3706 individuals, abnormal LVEDV (hazard ratio = 4.02) and LVESV (hazard ratio = 6.46) helped predict mortality (P < .001). Similarly, LVESV and LVEDV demonstrated improved discrimination when compared with CAD risk factors or CAD extent and severity (P < .05). CONCLUSION: LV dysfunction and volumes measured with cardiac CT angiography augment risk prediction and discrimination for future mortality.

Sex-based prognostic implications of nonobstructive coronary artery disease: results from the international multicenter CONFIRM study.

PURPOSE: To determine the clinical outcomes of women and men with nonobstructive coronary artery disease ( CAD coronary artery disease ) with coronary computed tomographic (CT) angiography data in patients who were similar in terms of CAD coronary artery disease risk factors, angina typicality, and CAD coronary artery disease extent and distribution. MATERIALS AND METHODS: Institutional review board approval was obtained for all participating sites, with either informed consent or waiver of informed consent. In a prospective international multicenter cohort study of 27 125 patients undergoing coronary CT angiography at 12 centers, 18 158 patients with no CAD coronary artery disease or nonobstructive (<50% stenosis) CAD coronary artery disease were examined. Men and women were propensity matched for age, CAD coronary artery disease risk factors, angina typicality, and CAD coronary artery disease extent and distribution, which resulted in a final cohort of 11 462 subjects. Nonobstructive CAD coronary artery disease presence and extent were related to incident major adverse cardiovascular events ( MACE major adverse cardiovascular events ), which were inclusive of death and myocardial infarction and were estimated by using multivariable Cox proportional hazards models. RESULTS: At a mean follow-up ± standard deviation of 2.3 years ± 1.1, MACE major adverse cardiovascular events occurred in 164 patients (0.6% annual event rate). After matching, women and men experienced identical annualized rates of myocardial infarction (0.2% vs 0.2%, P = .72), death (0.5% vs 0.5%, P = .98), and MACE major adverse cardiovascular events (0.6% vs 0.6%, P = .94). In multivariable analysis, nonobstructive CAD coronary artery disease was associated with similarly increased MACE major adverse cardiovascular events for both women (hazard ratio: 1.96 [95% confidence interval { CI confidence interval }: 1.17, 3.28], P = .01) and men (hazard ratio: 1.77 [95% CI confidence interval : 1.07, 2.93], P = .03). CONCLUSION: When matched for age, CAD coronary artery disease risk factors, angina typicality, and nonobstructive CAD coronary artery disease extent, women and men experience comparable rates of incident mortality and myocardial infarction.

Prognostic significance of calcified plaque among symptomatic patients with nonobstructive coronary artery disease.

BACKGROUND: Coronary artery calcium (CAC) is a well-established predictor of clinical outcomes for population screening. Limited evidence is available as to its predictive value in symptomatic patients without obstructive coronary artery disease (CAD). The aim of the current study was to assess the prognostic value of CAC scores among symptomatic patients with nonobstructive CAD. METHODS: From the COronary Computed Tomographic Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter (CONFIRM) registry, 7,200 symptomatic patients with nonobstructive CAD (<50% coronary stenosis) on coronary-computed tomographic angiography were prospectively enrolled and followed for a median of 2.1 years. Patients were categorized as without (0% stenosis) or with (>0% but <50% coronary stenosis) a luminal stenosis. CAC scores were calculated using the Agatston method. Univariable and multivariable Cox proportional hazard models were employed to estimate all-cause mortality and/or myocardial infarction (MI). Four-year death and death or MI rates were 1.9% and 3.3%. RESULTS: Of the 4,380 patients with no luminal stenosis, 86% had CAC scores of <10 while those with a luminal stenosis had more prevalent and extensive CAC with 31.9% having a CAC score of ≥100. Among patients with no luminal stenosis, CAC was not predictive of all-cause mortality (P = .44). However, among patients with a luminal stenosis, 4-year mortality rates ranged from 0.8% to 9.8% for CAC scores of 0 to ≥400 (P < .0001). The mortality hazard was 6.0 (P = .004) and 13.3 (P < .0001) for patients with a CAC score of 100-399 and ≥400. In patients with a luminal stenosis, CAC remained independently predictive in all-cause mortality (P < .0001) and death or MI (P < .0001) in multivariable models containing CAD risk factors and presenting symptoms. CONCLUSIONS: CAC allows for the identification of those at an increased hazard for death or MI in symptomatic patients with nonobstructive disease. From the CONFIRM registry, the extent of CAC was an independent estimator of long-term prognosis among symptomatic patients with luminal stenosis and may further define risk and guide preventive strategies in patients with nonobstructive CAD.

Calcium score, coronary artery disease extent and severity, and clinical outcomes among low Framingham risk patients with low vs high lifetime risk: results from the CONFIRM registry.

BACKGROUND: Short-term risk scores, such as the Framingham risk score (FRS), frequently classify younger patients as low risk despite the presence of uncontrolled cardiovascular risk factors. Among patients with low FRS, estimation of lifetime risk is associated with significant differences in coronary arterial calcium scores (CACS); however, the relationship of lifetime risk to coronary atherosclerosis on coronary CT angiography (CCTA) and prognosis has not been studied. METHODS AND RESULTS: We evaluated asymptomatic 20-60-year-old patients without diabetes or known coronary artery disease (CAD) within an international CT registry who underwent ≥64-slice CCTA. Patients with low FRS (<10%) were stratified as low (<39%) or high (≥39%) lifetime CAD risk, and compared for the presence and severity of CAD and prognosis for death, myocardial infarction, and late coronary revascularization (>90 days post CCTA). 1,863 patients of mean age of 47 years were included, with 48% of the low FRS patients at high lifetime risk. Median follow-up was 2.0 years. Comparing low-to-high lifetime risk, respectively, the prevalence of any CAD was 32% vs 41% (P < .001) and ≥50% stenosis was 7.4% vs 9.6% (P = .09). For those with CAD, subjects at low vs high lifetime risk had lower CACS (median 12 [IQR 0-94] vs 38 [IQR 0.05-144], P = .02) and less purely calcified plaque, 35% vs 45% (P < .001). Prognosis did not differ due to low number of events. CONCLUSION: Assessment of lifetime risk among patients at low FRS identified those with the increase in CAD prevalence and severity and a higher proportion of calcified plaque.

Multimodality imaging of a rare intracardiac bronchogenic cyst.

The authors report a case of pathologically proven intracardiac bronchogenic cyst embedded within the interatrial septum of a 30-year-old woman presenting with chest pain and first-degree AV block. Multimodality imaging played an essential role in the discovery, investigation, and diagnosis of this extremely rare entity.

Coronary artery imaging with single-source rapid kilovolt peak-switching dual-energy CT.

PURPOSE: To evaluate beam-hardening (BH) artifact reduction in coronary computed tomography (CT) angiography with dual-energy CT, to define the optimal monochromatic-energy levels for coronary and myocardial signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in dual-energy CT, and to compare these levels with single-energy CT. MATERIALS AND METHODS: The study was approved by the institutional review board and/or ethics committee at each site. Patients provided informed consent. Thirty-nine patients were prospectively enrolled to undergo dual-energy CT, and 25 also underwent single-energy CT. Myocardial and coronary SNR, CNR, and iodine concentration were measured across multiple segments at varying monochromatic energy levels (40-140 keV). BH was defined as signal decrease in basal inferior wall versus midinferior wall, and signal increase in midseptum versus midinferior wall. Generalized estimating equation was used to identify optimal monochromatic-energy levels and compare them with single-energy CT. RESULTS: BH was noted at single-energy CT with basal inferior wall mean reduction of 19.7 HU ± 29.2 (standard deviation) and midseptum increase of 46.3 HU ± 36.3. There was reduction in this artifact at 90 keV or greater (1.7 HU ± 18.4 in basal inferior wall and 20.1 HU ± 37.5 in midseptum at 90 keV; P < .05). SNR and CNR were higher in the myocardium and coronary arteries at 60-80 keV than single-energy CT (myocardium: SNR, 3.02 vs 2.39, and CNR, 6.73 vs 5.16; coronary arteries: SNR, 10.83 vs 7.75, and CNR, 13.31 vs 9.54; P < .01). Mean iodine concentration in resting myocardium was 2.19 mg/mL ± 0.57. CONCLUSION: Rapid kilovolt peak-switching dual-energy CT resulted in significant BH reduction and improvements in SNR and CNR in the myocardium and coronary arteries.

Triage of patients presenting with chest pain to the emergency department: implementation of coronary CT angiography in a large urban health care system.

OBJECTIVE: There is growing evidence supporting the use of coronary CT angiography (CTA) to triage patients in the emergency department (ED) with acute chest pain and low risk of acute coronary syndrome (ACS). We hypothesized that coronary CTA can guide early management and safely discharge patients by introducing a dedicated patient management protocol. SUBJECTS AND METHODS: We conducted a prospective cohort study in three EDs of a large health care system (> 1300 beds). Five hundred twenty-nine patients (mean age, 52.1 years; 56% women) with chest pain, negative cardiac enzyme results, normal or nondiagnostic ECG findings, and a thrombolysis in myocardial infarction (TIMI) risk score of 2 or less were admitted and underwent CTA. A new dedicated chest pain triage protocol (levels 1-5) was implemented. On the basis of CTA findings, patients were stratified into one of the following four groups: 0, low (negative CTA findings); 1, mild (1-49% stenosis); 2, moderate (50-69% stenosis); or 3, severe (≥ 70% stenosis) risk of ACS. Outcome measures included major adverse cardiac events (MACEs) during the first 30 days after CTA, downstream testing results, and length of stay (LOS). LOS was compared before and after implementation of our chest pain triage protocol. RESULTS: Three hundred seventeen patients (59.9%) with negative CTA findings and 151 (28.5%) with mild stenosis were discharged from the ED with a very low downstream testing rate and a very low MACE rate (negative predictive value = 99.8%). Twenty-five patients (4.7%) had moderate stenosis (n = 17 undergoing further testing). Thirty-six patients (6.8%) had stenosis of 70% or greater by CTA (n = 34 positive by invasive angiography or SPECT-myocardial perfusion imaging). The sensitivity of CTA was 94%. The rate of MACEs in patients with stenosis of 70% or greater (8.3%) was significantly higher (p < 0.001) than in patients with negative CTA findings (0%) or those with mild stenosis (0.2%). A 51% decrease in LOS-from 28.8 to 14.0 hours--was noted after implementation of the dedicated chest pain protocol (p < 0.001). CONCLUSION: Chest pain patients with negative or mild nonobstructive CTA findings can be safely discharged from the ED without further testing. Implementation of a dedicated chest pain triage protocol is critical for the success of a coronary CTA program.

High pericardial and peri-aortic adipose tissue burden in pre-diabetic and diabetic subjects.

BACKGROUND: Central obesity in relation to insulin resistance is strongly linked to the development of type 2 diabetes. However, data regarding the association between pericardial and peri-aortic adiposity, a potential estimate of visceral adipose tissue burden, and pre-diabetes status remains unclear.The aim of this study was to examine whether the degree of pericardial and thoracic peri-aortic adipose tissue, when quantified by multi-detector computed tomography (MDCT), differs significantly in a normal, pre-diabetic, and overtly diabetic population. METHODS: We studied 562 consecutive subjects including 357 healthy, 155 pre-diabetic, and 50 diabetic patients selected from participants who underwent annual health surveys in Taiwan. Pre-diabetes status was defined by impaired fasting glucose or impaired glucose intolerance according to American Diabetes Association guidelines. Pericardial (PCF) and thoracic peri-aortic (TAT) adipose tissue burden was assessed using a non-contrast 16-slice multi-detector computed tomography (MDCT) dataset with off-line measurement (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). Body fat composition, serum high-sensitivity C-reactive protein (hs-CRP) level and insulin resistance (HOMA-IR) were also assessed. RESULTS: Patients with diabetes and pre-diabetes had greater volume of PCF (89 ± 24.6, 85.3 ± 28.7 & 67.6 ± 26.7 ml, p < 0.001) as well as larger TAT (9.6 ± 3.1 ml vs 8.8 ± 4.2 & 6.6 ± 3.5 ml, respectively, p < 0.001) when compared to the normal group, although there were no significant differences in adiposity between the diabetic and pre-diabetic groups. For those without established diabetes in our study, increasing TAT burden, but not PCF, appear to correlate with insulin resistance (HOMA-IR) and hs-CRP in the multivariable models. CONCLUSIONS: Pre-diabetic and diabetic subjects, compared to normoglycemia, were associated with significantly higher pericardial and peri-aortic adipose tissue burden. In addition, visceral fat accumulation adjacent to the thoracic aorta seemed to exert a significant impact on insulin resistance and systemic inflammation.

Assessing cardiovascular risk with mammography and non-contrast chest CT: A review of the literature and clinical implications.

Coronary artery disease (CAD) is the leading cause of mortality and disability globally. In the United States, about 7.2% of adults aged 20 and older are affected by CAD. However, due to its progression over decades, CAD is often undetected and unnoticed until plaque ruptures. This leads to partial or complete artery blockage, resulting in myocardial infarction. Thus, new screening methods for early detection of CAD are needed to prevent and minimize the morbidity and mortality from CAD. Vascular calcifications seen on mammography and non-contrast chest CT (NCCT) can be used for the early detection of CAD and are an accurate predictor of cardiovascular risk. This paper aims to review the basic epidemiology, pathophysiology, imaging findings, and correlation of long-term cardiovascular outcomes with vascular calcifications on mammography and NCCT.