Relationship between the circulating N-terminal pro B-type natriuretic peptide and the risk of carotid artery plaque in different glucose metabolic states in patients with coronary heart disease: a CSCD-TCM plus study in China

OBJECTIVE

Circulating N-terminal pro B-type natriuretic peptide (NT-proBNP) is a marker for heart failure in patients with coronary heart disease (CHD) and associated with glycemic abnormalities. Studies on the association and diagnostic value of NT-proBNP in carotid plaques (CAP) in patients with CHD are limited.

METHODS

The relationships between NT-proBNP and the risk of CAP in different glucose metabolic states, sexes, and age categories were also examined using 5,093 patients diagnosed with CHD. The NT-proBNP tertiles were used to divide patients into three groups in which the NT-proBNP levels, blood glucose levels, the occurrence of CAP, and the number and nature of CAP were measured using normoglycemic (NG), prediabetes (Pre-DM), and diabetes mellitus (DM) glucose metabolic statuses. Logistic regression analyses were used to compare the relationship between NT-proBNP and the risk of CAP occurrence and the number and nature of CAP. The diagnostic value of NT-proBNP for CAP risk was measured using receiver operating characteristic (ROC) curves.

RESULTS

We found a 37% relative increase in the correlation between changes in NT-proBNP per standard deviation (SD) and the incidence of CAP. After adjusting for potential confounders, NT-proBNP at the T3 level was found to be associated with an increased CAP odds ratio (OR) when T1 was used as the reference. This relationship was also present in males, patients aged > 60 years, or both pre-DM and DM states. NT-proBNP was more likely to present as hypoechoic plaques at T1 and as mixed plaques at T3. We also measured the diagnostic accuracy of CAP for NT-proBNP in patients with CHD, with an AUC value of 0.627(95% CI 0.592-0.631), sensitivity of 50.7%, and specificity of 68.0%.

CONCLUSION

An increase in NT-proBNP was significantly associated with the risk of CAP in patients with CHD, especially in males and patients aged > 60 years, and exhibited specific characteristics under different glucose metabolism states. Trial registration The study was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine (Approval number TJUTCM-EC20210007) and certified by the Chinese Clinical Trials Registry on April 4, 2022 (Registration number ChiCTR2200058296) and March 25, 2022 by ClinicalTrials.gov (registration number NCT05309343).

The estimation of left ventricular function using prospective ECG-triggered coronary CT angiography

BACKGROUND

Coronary computed tomography angiography (CCTA) is vital for diagnosing coronary artery disease; however, prospective ECG-triggered acquisition, minimizing radiation exposure, limits left ventricular (LV) ejection fraction (EF) evaluation. We aimed to assess the feasibility and utility of LVEF100msec, a new index for estimating LV function using volumetric changes during 100 msec within systole.

METHODS

This retrospective study analyzed patients who underwent prospective ECG-triggered CCTA with systolic acquisition between January 2015 and June 2022. The LVEF100msec was calculated using the maximum and minimum LV volumes among the three phases (300, 350, and 400 msec post-QRS) and expressed as a percentage. Patients were classified into normal, mild-moderately reduced, or severely reduced LV function categories based on the reference test. The LVEF100msec was compared among groups, and the optimal cutoff value of LVEF100msec for predicting severe LV dysfunction was investigated.

RESULTS

The study included 271 patients (median age ​= ​58 years, 52% male). LVEF was normal in 188 (69.4%), mild-moderately reduced in 57 (21.0%), and severely reduced in 26 (9.6%) patients. Median LVEF100msec value was 9.0 (6.7-12.6) for normal LV function, 4.7 (3.1-8.8) for mild-moderately reduced, and 2.9 (1.5-3.8) for severely reduced LV function. LVEF100msec values significantly differed among categories (p ​< ​0.001). The optimal LVEF100msec cutoff for severe LV dysfunction was 4.3%, with an AUC of 0.924, sensitivity of 88%, and specificity of 89%.

CONCLUSION

The LVEF100msec may serve as a valuable indicator of severe LV dysfunction.

Evaluation of Atherosclerotic Plaque in Non-invasive Coronary Imaging

Coronary artery disease (CAD) is the leading cause of morbidity and mortality worldwide. Over the last decade coronary computed tomography angiography (CCTA) has gained wide acceptance as a reliable, cost-effective and non-invasive modality for diagnosis and prognostication of CAD. Use of CCTA is now expanding to characterization of plaque morphology and identification of vulnerable plaque. Additionally, CCTA is developing as a non-invasive modality to monitor plaque progression, which holds future potential in individualizing treatment. In this review, we discuss the role of CCTA in diagnosis and management of CAD. Additionally, we discuss the recent advancements and the potential clinical applications of CCTA in management of CAD.

Effect of smoking status on coronary artery disease among Chinese post-menopausal women

Smoking is a prominent risk factor of cardiovascular diseases. The occurrence of myocardial infarction and mortality in smokers with cardiovascular diseases is several times higher than that in non-smokers. Smoking is associated with gender-independent enhanced mortality. We determined the effect of smoking status on coronary artery disease (CAD) and coronary computed tomography angiography (CCTA) in Chinese post-menopausal women. Among these patients, those with significant CAD (≥50 % luminal narrowing) were further classified into one-, two-, or three-vessel disease according to CCTA results. The following events were recorded: all-cause mortality, non-fatal infarction and unstable angina. 2332 patients evaluated with CCTA included 1668 never smokers (71.5 %), 475 former smokers (20.4 %), and 189 current smokers (8.1 %). The current smokers exhibit greater luminal narrowing as observed on CCTA (p < 0.001) than the other subjects. During the median 685 ± 269.8 days follow-up period, never-smoking women have a low incidence of events, whereas former and current smokers are associated with an increased incidence of such event (p < 0.001). Furthermore, current smoking and the presence of multiple-vessel disease on CCTA are independently associated with the events in the logistic regression analysis. Smoking status is related to significant CAD and luminal narrowing on CCTA in the Chinese post-menopausal smoking women. In addition, current smoking and the presence of multiple-vessel disease on CCTA can independently predict events of all-cause mortality, non-fatal infarction or unstable angina.

Association between serum N-terminal pro-B-type natriuretic peptide levels and characteristics of coronary atherosclerotic plaque detected by coronary computed tomography angiography

The aim of the present study was to explore the association between the levels of serum N-terminal pro-B-type natriuretic peptide (NT-pro BNP) and the characteristics of coronary atherosclerotic plaque detected by coronary computed tomography angiography (CCTA), in patients with unstable angina (UA). A total of 202 patients (age range, 47-82 years) were divided into the following three groups: Non-cardiac disease group (57 patients); stable angina pectoris (SAP) group (62 patients); and UA group (83 patients). There were significant differences between the serum NT-pro BNP levels among the three groups (P=0.007). However, in multivariant diagnoses, NT-pro BNP level was not an independent risk factor for UA. The levels of serum NT-pro BNP were observed to be positively correlated with the number of vessels involved (r=0.462; P<0.001), SIS (r=0.475; P<0.001), segment-stenosis score (r=0.453; P<0.001), coronary calcification score (r=0.412; P=0.001), number of obstructive diseases (r=0.346; P<0.001), and the number of segments with non-calcified plaque (r=0.235; P=0.017), mixed plaque (r=0.234; P=0.017) and calcified plaque (r=0.431; P<0.001). The levels of serum NT-pro BNP were significantly higher in patients with UA and left main-left anterior descending (LM-LAD) disease, compared with UA patients without LM-LAD disease (P<0.001). In addition, serum NT-pro BNP was significantly higher in patients with obstructive disease and UA than in those without obstructive disease (P<0.001). The area under the curve of log(NT-pro BNP) was 0.656 (P=0.006; optimal cut-off value, 1.74; sensitivity, 77.6%; specificity, 51.9%). In conclusion, the levels of serum NT-pro BNP are associated with the burden and severity of coronary artery atherosclerotic disease in patients with UA, and may be helpful in risk stratification of patients with UA.

Human Mesenchymal Stem Cell Delivery System Modulates Ischemic Cardiac Remodeling With an Increase of Coronary Artery Blood Flow

Ways for extending the longevity of stem cells are imperative to attain diverse expected therapeutic effects. Here, we constructed a three-dimentional (3D) scaffold system for human mesenchymal stem cell (hMSC) delivery. Intramyocardial injections of porous PEI1.8k blended with poly(lactic-co-glycolic acid) (PLGA) (PLGA/PEI1.8k) (PPP) microparticles by physical electrostatic conjugation and structural entrapment of hMSCs demonstrated enhanced functional and geometric improvements on post-infarct cardiac remodeling in rats. In the hMSC-loaded PPP delivery, increases of coronary artery blood flow rate and in vivo engraftment rate as well as time-dependent functional, geometric, and pathologic findings reversing post-infarct cardiac remodeling account for improved left ventricular (LV) systolic function up to the level of sham thoracotomy group. This study expands our understanding by proving that increase of coronary artery blood flow augmented functional recovery of hMSC-loaded PPP delivery system after myocardial infarction (MI).

Korean guidelines for the appropriate use of cardiac CT

The development of cardiac CT has provided a non-invasive alternative to echocardiography, exercise electrocardiogram, and invasive angiography and cardiac CT continues to develop at an exponential speed even now. The appropriate use of cardiac CT may lead to improvements in the medical performances of physicians and can reduce medical costs which eventually contribute to better public health. However, until now, there has been no guideline regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist clinicians and other health professionals in the use of cardiac CT for diagnosis and treatment of heart diseases, especially in patients at high risk or suspected of heart disease.

CT angiography in the diagnosis of cardiovascular disease: a transformation in cardiovascular CT practice

Computed tomography (CT) angiography represents the most important technical development in CT imaging and it has challenged invasive angiography in the diagnostic evaluation of cardiovascular abnormalities. Over the last decades, technological evolution in CT imaging has enabled CT angiography to become a first-line imaging modality in the diagnosis of cardiovascular disease. This review provides an overview of the diagnostic applications of CT angiography (CTA) in cardiovascular disease, with a focus on selected clinical challenges in some common cardiovascular abnormalities, which include abdominal aortic aneurysm (AAA), aortic dissection, pulmonary embolism (PE) and coronary artery disease. An evidence-based review is conducted to demonstrate how CT angiography has changed our approach in the diagnosis and management of cardiovascular disease. Radiation dose reduction strategies are also discussed to show how CT angiography can be performed in a low-dose protocol in the current clinical practice.

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.

Incremental prognostic value of coronary computed tomographic angiography over coronary artery calcium score for risk prediction of major adverse cardiac events in asymptomatic diabetic individuals

BACKGROUND

Coronary artery disease (CAD) diagnosis by coronary computed tomographic angiography (CCTA) is useful for identification of symptomatic diabetic individuals at heightened risk for death. Whether CCTA-detected CAD enables improved risk assessment of asymptomatic diabetic individuals beyond clinical risk factors and coronary artery calcium scoring (CACS) remains unexplored.

METHODS

From a prospective 12-center international registry of 27,125 individuals undergoing CCTA, we identified 400 asymptomatic diabetic individuals without known CAD. Coronary stenosis by CCTA was graded as 0%, 1-49%, 50-69%, and ≥70%. CAD was judged on a per-patient, per-vessel and per-segment basis as maximal stenosis severity, number of vessels with ≥50% stenosis, and coronary segments weighted for stenosis severity (segment stenosis score), respectively. We assessed major adverse cardiovascular events (MACE) - inclusive of mortality, nonfatal myocardial infarction (MI), and late target vessel revascularization ≥90 days (REV) - and evaluated the incremental utility of CCTA for risk prediction, discrimination and reclassification.

RESULTS

Mean age was 60.4 ± 9.9 years; 65.0% were male. At a mean follow-up 2.4 ± 1.1 years, 33 MACE occurred (13 deaths, 8 MI, 12 REV) [8.25%; annualized rate 3.4%]. By univariate analysis, per-patient maximal stenosis [hazards ratio (HR) 2.24 per stenosis grade, 95% confidence interval (CI) 1.61-3.10, p < 0.001], increasing numbers of obstructive vessels (HR 2.30 per vessel, 95% CI 1.75-3.03, p < 0.001) and segment stenosis score (HR 1.14 per segment, 95% CI 1.09-1.19, p < 0.001) were associated with increased MACE. After adjustment for CAD risk factors and CACS, maximal stenosis (HR 1.80 per grade, 95% CI 1.18-2.75, p = 0.006), number of obstructive vessels (HR 1.85 per vessel, 95% CI 1.29-2.65, p < 0.001) and segment stenosis score (HR 1.11 per segment, 95% CI 1.05-1.18, p < 0.001) were associated with increased risk of MACE. Beyond age, gender and CACS (C-index 0.64), CCTA improved discrimination by maximal stenosis, number of obstructive vessels and segment stenosis score (C-index 0.77, 0.77 and 0.78, respectively). Similarly, CCTA findings improved risk reclassification by per-patient maximal stenosis [integrated discrimination improvement (IDI) index 0.03, p = 0.03] and number of obstructive vessels (IDI index 0.06, p = 0.002), and by trend for segment stenosis score (IDI 0.03, p = 0.06).

CONCLUSION

For asymptomatic diabetic individuals, CCTA measures of CAD severity confer incremental risk prediction, discrimination and reclassification on a per-patient, per-vessel and per-segment basis.

Optimized prognostic score for coronary computed tomographic angiography: results from the CONFIRM registry (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry)

OBJECTIVES

The aim of this study was to analyze the predictive value of coronary computed tomography angiography (CCTA) and to model and validate an optimized score for prognosis of 2-year survival on the basis of a patient population with suspected coronary artery disease (CAD).

BACKGROUND

Coronary computed tomography angiography carries important prognostic information in addition to the detection of obstructive CAD. But it is still unclear how the results of CCTA should be interpreted in the context of clinical risk predictors.

METHODS

The analysis is based on a test sample of 17,793 patients and a validation sample of 2,506 patients, all with suspected CAD, from the international CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry. On the basis of CCTA data and clinical risk scores, an optimized score was modeled. The endpoint was all-cause mortality.

RESULTS

During a median follow-up of 2.3 years, 347 patients died. The best CCTA parameter for prediction of mortality was the number of proximal segments with mixed or calcified plaques (C-index 0.64, p < 0.0001) and the number of proximal segments with a stenosis >50% (C-index 0.56, p = 0.002). In an optimized score including both parameters, CCTA significantly improved overall risk prediction beyond National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) score as best clinical score. According to this score, a proximal segment with either a mixed or calcified plaque or a stenosis >50% is equivalent to a 5-year increase in age or the risk of smoking.

CONCLUSIONS

In CCTA, both plaque burden and stenosis, particularly in proximal segments, carry incremental prognostic value. A prognostic score on the basis of this data can improve risk prediction beyond clinical risk scores.

Prognostic utility of coronary computed tomographic angiography

Coronary computed tomographic angiography (CCTA) employing CT scanners of 64-detector rows or greater represents a noninvasive method that enables accurate detection and exclusion of anatomically obstructive coronary artery disease (CAD), providing excellent diagnostic information when compared to invasive angiography. There are numerous potential advantages of CCTA beyond simply luminal stenosis assessment including quantification of atherosclerotic plaque volume as well as assessment of plaque composition, extent, location and distribution. In recent years, an array of studies has evaluated the prognostic utility of CCTA findings of CAD for the prediction of major adverse cardiac events, all-cause death and plaque instability. This prognostic information enhances risk stratification and, if properly acted upon, may improve medical therapy and/or behavioral changes that may enhance event-free survival. The goal of the present article is to summarize the current status of the prognostic utility of CCTA findings of CAD.

Cost-effectiveness analysis of coronary artery disease screening in HIV-infected men

BACKGROUND

HIV-infected patients are at increased risk of coronary artery disease (CAD). We evaluated the cost-effectiveness of cardiac screening for HIV-positive men at intermediate or greater CAD risk.

DESIGN

We developed a lifetime microsimulation model of CAD incidence and progression in HIV-infected men.

METHODS

Input parameters were derived from two HIV cohort studies and the literature. We compared no CAD screening with stress testing and coronary computed tomography angiography (CCTA)-based strategies. Patients with test results indicating 3-vessel/left main CAD underwent invasive coronary angiography (ICA) and received coronary artery bypass graft surgery. In the stress testing + medication and CCTA + medication strategies, patients with 1-2-vessel CAD results received lifetime medical treatment without further diagnostics whereas in the stress testing + intervention and CCTA + intervention strategies, patients with these results underwent ICA and received percutaneous coronary intervention.

RESULTS

Compared to no screening, the stress testing + medication, stress testing + intervention, CCTA + medication, and CCTA + intervention strategies resulted in 14, 11, 19, and 14 quality-adjusted life days per patient and incremental cost-effectiveness ratios of 49,261, 57,817, 34,887 and 56,518 Euros per quality-adjusted life year (QALY), respectively. Screening only at higher CAD risk thresholds was more cost-effective. Repeated screening was clinically beneficial compared to one-time screening, but only stress testing + medication every 5 years remained cost-effective. At a willingness-to-pay threshold of 83,000 €/QALY (∼ 100,000 US$/QALY), implementing any CAD screening was cost-effective with a probability of 75-95%.

CONCLUSIONS

Screening HIV-positive men for CAD would be clinically beneficial and comes at a cost-effectiveness ratio comparable to other accepted interventions in HIV care.

Matrix metalloproteinase-9 (MMP-9) and myeloperoxidase (MPO) levels in patients with nonobstructive coronary artery disease detected by coronary computed tomographic angiography

RATIONALE AND OBJECTIVES

The aim of this study was to evaluate whether matrix metalloproteinase-9 (MMP-9) and myeloperoxidase (MPO) are elevated in patients with nonobstructive coronary artery disease.

MATERIALS AND METHODS

Eighty-four patients with nonobstructive coronary artery disease (group A) and 90 patients with no coronary plaques (group B) were enrolled. MMP-9 and MPO levels were compared between the two groups. The relationships between these biomarkers and Framingham risk score were analyzed. Receiver-operating characteristic curves were used to evaluate the ability of these biomarkers to predict the presence of coronary artery plaques.

RESULTS

The MMP-9 and MPO values in group A were significantly higher than in group B (P < .001). The levels of MMP-9 and MPO showed significant correlations with Framingham risk score (r = 0.796, P < .001, and r = 0.409, P < .001, respectively). The areas under the receiver-operating characteristic curves for MMP-9 and MPO were 0.80 (95% confidence interval, 0.74-0.87) and 0.74 (95% confidence interval, 0.66-0.81), respectively.

CONCLUSIONS

Levels of MMP-9 and MPO are positively correlated with Framingham risk score. Additionally, in patients with nonobstructive coronary artery disease, elevated levels of MMP-9 and MPO may identify patients at risk for future myocardial infarction or sudden cardiac death.

All-cause mortality benefit of coronary revascularization vs. medical therapy in patients without known coronary artery disease undergoing coronary computed tomographic angiography: results from CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry)

AIMS

To date, the therapeutic benefit of revascularization vs. medical therapy for stable individuals undergoing invasive coronary angiography (ICA) based upon coronary computed tomographic angiography (CCTA) findings has not been examined.

METHODS AND RESULTS

We examined 15 223 patients without known coronary artery disease (CAD) undergoing CCTA from eight sites and six countries who were followed for median 2.1 years (interquartile range 1.4-3.3 years) for an endpoint of all-cause mortality. Obstructive CAD by CCTA was defined as a ≥50% luminal diameter stenosis in a major coronary artery. Patients were categorized as having high-risk CAD vs. non-high-risk CAD, with the former including patients with at least obstructive two-vessel CAD with proximal left anterior descending artery involvement, three-vessel CAD, and left main CAD. Death occurred in 185 (1.2%) patients. Patients were categorized into two treatment groups: revascularization (n = 1103; 2.2% mortality) and medical therapy (n = 14 120, 1.1% mortality). To account for non-randomized referral to revascularization, we created a propensity score developed by logistic regression to identify variables that influenced the decision to refer to revascularization. Within this model (C index 0.92, χ2 = 1248, P < 0.0001), obstructive CAD was the most influential factor for referral, followed by an interaction of obstructive CAD with pre-test likelihood of CAD (P = 0.0344). Within CCTA CAD groups, rates of revascularization increased from 3.8% for non-high-risk CAD to 51.2% high-risk CAD. In multivariable models, when compared with medical therapy, revascularization was associated with a survival advantage for patients with high-risk CAD [hazards ratio (HR) 0.38, 95% confidence interval 0.18-0.83], with no difference in survival for patients with non-high-risk CAD (HR 3.24, 95% CI 0.76-13.89) (P-value for interaction = 0.03).

CONCLUSION

In an intermediate-term follow-up, coronary revascularization is associated with a survival benefit in patients with high-risk CAD by CCTA, with no apparent benefit of revascularization in patients with lesser forms of CAD.

Incremental prognostic value of different components of coronary atherosclerotic plaque at cardiac CT angiography beyond coronary calcification in patients with acute chest pain

PURPOSE

To systematically evaluate the incremental predictive value of cardiac computed tomographic (CT) angiography beyond the assessment of coronary artery calcium (CAC) in patients who present with acute chest pain but without evidence of acute coronary syndrome (ACS).

MATERIALS AND METHODS

The human research committee approved this study and waived the need for individual written informed consent. The study was HIPAA compliant. A total of 458 patients (36% male; mean age, 55 years ± 11) with acute chest pain at low to intermediate risk for coronary artery disease underwent coronary calcification assessment with cardiac CT angiography. All patients who did not experience ACS at index hospitalization were followed for instances of a major adverse cardiac event (MACE), such as a myocardial infarct, revascularization, cardiac death, or angina requiring hospitalization. CAC score and cardiac CT angiography were used to derive the presence and extent of atherosclerotic plaque (calcified, noncalcified, or mixed), and obstructive lesions (>50% luminal narrowing) were related to outcomes by using univariate and adjusted Cox proportional hazards models.

RESULTS

Of the 458 patients, 70 (15%) experienced MACE (median follow-up, 13 months). Patients with no plaque at cardiac CT angiography remained free of events during the follow-up period, while 11 (5%) of 215 patients with no CAC had MACE. The extent of plaque was the strongest predictor of MACE independent of traditional risk factors (hazard ratio [HR], 151.77 for four or more segments containing plaque as compared with those containing no plaque; P < .001). Patients with mixed plaque were more likely to experience MACE (HR, 86.96; P = .002) than those with exclusively noncalcified plaque (HR, 58.06; P = .005) or exclusively calcified plaque (HR, 32.94; P = .02).

CONCLUSION

The strong prognostic value of cardiac CT angiography is incremental to its known diagnostic value in patients with acute chest pain without ACS and is independent of traditional risk factors and CAC.

Value of coronary computed tomography as a prognostic tool

Coronary computed tomography angiography (CCTA) has become an important part of our armamentarium for noninvasive diagnosis of coronary artery disease (CAD). Emerging technologies have produced lower radiation dose, improved spatial and temporal resolution, as well as information about coronary physiology. Although the prognostic role of coronary artery calcium scoring is known, similar evidence for CCTA has only recently emerged. Initial, small studies in various patient populations have indicated that CCTA-identified CAD may have a prognostic value. These findings were confirmed in a recent analysis of the international, prospective Coronary CT Angiography Evaluation For Clinical Outcomes: An International Multicenter (CONFIRM) registry. An incremental increase in mortality was found with a worse severity of CAD on a per-patient, per-vessel, and per-segment basis. In addition, age-, sex-, and ethnicity-based differences in mortality were also found. Whether changing our management algorithms based on these findings will affect outcomes is unclear. Large prospective studies utilizing targeted management strategies for obstructive and nonobstructive CAD are required to incorporate these recent findings into our daily practice.

Cardiac CT in the emergency department

Current triage strategies are not effective in correctly identifying patients suffering from acute coronary syndrome (ACS). The diagnostic workup of patients presenting with acute chest pain continues to represent a major challenge for emergency department (ED) personnel. This statement holds especially true for patients with a low to intermediate likelihood for ACS. Taking current concepts for the diagnosis and management of patients presenting with acute chest pain to the ED into account, this article discusses the evidence and potential role of coronary computed tomography angiography to improve management of patients with possible ACS.

Lack of sex disparity in cardiovascular testing after coronary computerized tomographic angiography

OBJECTIVES

  The authors assessed whether there was a sex disparity in testing of patients after coronary computerized tomographic angiography (CTA) was performed for emergency department (ED) patients with potential acute coronary syndromes (ACS). In theory, once coronary anatomy has been determined, any disparity in subsequent workup should not be the result of differences in presentation.

METHODS

  This was a prospective cohort study of ED patients who presented with potential ACS and received coronary CTAs at a university hospital. Demographics, history, cardiac risk factors, follow-up testing, and procedures were recorded. Follow-up at 30 days was obtained by structured record review and telephone contact. Patients were stratified by sex and coronary CTA results (max stenosis: none, 1% to 24%, 25% to 49%, 50% to 69%, and ≥70%). Main outcome was the relative risk (RR) of a male receiving a stress test or catheterization within 30 days, stratified by categories of percent maximal stenosis.

RESULTS

  A total of 1,144 patients received coronary CTAs (mean ± SD age = 47.8 ± 8.7 years), 55% were female, and 64% were black or African American. Overall, 161 patients received follow-up testing within 30 days, 113 during their index visit. Men were more likely to receive further testing (RR = 1.51; 95% confidence interval [CI] = 1.14 to 1.99) compared to women. However, when stratified by percentage of stenosis, men were not more likely to receive further testing within 30 days after coronary CTA compared to women (RR = 1.14; 95% CI = 0.68 to 1.91). In multivariable modeling for risk of further testing, stenosis remained significant (adjusted relative risk [aRR] = 1.51; 95% CI = 1.19 to 1.91), while male sex, age, race, and Thrombolysis in Myocardial Infarction (TIMI) risk score were not.

CONCLUSIONS

  Male patients with potential ACS who receive a coronary CTA as a part of their ED evaluation were no more likely than female patients to receive further testing within 30 days.

Age- and sex-related differences in all-cause mortality risk based on coronary computed tomography angiography findings results from the International Multicenter CONFIRM (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry) of 23,854 patients without known coronary artery disease

OBJECTIVES

We examined mortality in relation to coronary artery disease (CAD) as assessed by ≥64-detector row coronary computed tomography angiography (CCTA).

BACKGROUND

Although CCTA has demonstrated high diagnostic performance for detection and exclusion of obstructive CAD, the prognostic findings of CAD by CCTA have not, to date, been examined for age- and sex-specific outcomes.

METHODS

We evaluated a consecutive cohort of 24,775 patients undergoing ≥64-detector row CCTA between 2005 and 2009 without known CAD who met inclusion criteria. In these patients, CAD by CCTA was defined as none (0% stenosis), mild (1% to 49% stenosis), moderate (50% to 69% stenosis), or severe (≥70% stenosis). CAD severity was judged on a per-patient, per-vessel, and per-segment basis. Time to mortality was estimated using multivariable Cox proportional hazards models.

RESULTS

At a 2.3 ± 1.1-year follow-up, 404 deaths had occurred. In risk-adjusted analysis, both per-patient obstructive (hazard ratio [HR]: 2.60; 95% confidence interval [CI]: 1.94 to 3.49; p < 0.0001) and nonobstructive (HR: 1.60; 95% CI: 1.18 to 2.16; p = 0.002) CAD conferred increased risk of mortality compared with patients without evident CAD. Incident mortality was associated with a dose-response relationship to the number of coronary vessels exhibiting obstructive CAD, with increasing risk observed for nonobstructive (HR: 1.62; 95% CI: 1.20 to 2.19; p = 0.002), obstructive 1-vessel (HR: 2.00; 95% CI: 1.43 to 2.82; p < 0.0001), 2-vessel (HR: 2.92; 95% CI: 2.00 to 4.25; p < 0.0001), or 3-vessel or left main (HR: 3.70; 95% CI: 2.58 to 5.29; p < 0.0001) CAD. Importantly, the absence of CAD by CCTA was associated with a low rate of incident death (annualized death rate: 0.28%). When stratified by age <65 years versus ≥65 years, younger patients experienced higher hazards for death for 2-vessel (HR: 4.00; 95% CI: 2.16 to 7.40; p < 0.0001 vs. HR: 2.46; 95% CI: 1.51 to 4.02; p = 0.0003) and 3-vessel (HR: 6.19; 95% CI: 3.43 to 11.2; p < 0.0001 vs. HR: 3.10; 95% CI: 1.95 to 4.92; p < 0.0001) CAD. The relative hazard for 3-vessel CAD (HR: 4.21; 95% CI: 2.47 to 7.18; p < 0.0001 vs. HR: 3.27; 95% CI: 1.96 to 5.45; p < 0.0001) was higher for women as compared with men.

CONCLUSIONS

Among individuals without known CAD, nonobstructive and obstructive CAD by CCTA are associated with higher rates of mortality, with risk profiles differing for age and sex. Importantly, absence of CAD is associated with a very favorable prognosis.

Mortality risk in symptomatic patients with nonobstructive coronary artery disease: a prospective 2-center study of 2,583 patients undergoing 64-detector row coronary computed tomographic angiography

OBJECTIVES

We examined mortality risk in relation to extent and composition of nonobstructive plaques by 64-detector row coronary computed tomographic angiography (CCTA).

BACKGROUND

The prognostic significance of nonobstructive coronary artery plaques by CCTA is poorly understood.

METHODS

We prospectively evaluated consecutive adults from 2 centers undergoing 64-detector row CCTA without prior documented coronary artery disease (CAD) and without obstructive (≥50%) CAD by CCTA. Luminal diameter stenosis severity was classified for each segment as none (0%) or mild (1% to 49%), and plaque composition was classified as noncalcified, calcified, or mixed.

RESULTS

During 3.1 ± 0.5 years, 54 intermediate-term (≥90 days) deaths occurred among 2,583 patients (2.09%), with 4 early (<90 days) deaths. Adjusted for CAD risk factors, the presence of any nonobstructive plaque was associated with higher mortality (hazard ratio [HR]: 1.98, 95% confidence Interval [CI]: 1.06 to 3.69, p = 0.03), with the highest risk among those exhibiting nonobstructive CAD in 3 epicardial vessels (HR: 4.75, 95% CI: 2.10 to 10.75, p = 0.0002) or ≥5 segments (HR: 5.12, 95% CI: 2.16 to 12.10, p = 0.0002). Higher mortality for nonobstructive CAD was observed even among patients with low 10-year Framingham risk (3.4%, p < 0.0001) as well as those with no traditional, medically treatable CAD risk factors, including diabetes mellitus, hypertension, and dyslipidemia (6.7%, p < 0.0001). No independent relationship between plaque composition and incident mortality was observed. Importantly, patients without evident plaque experienced a low rate of incident death during follow-up (0.34%/year).

CONCLUSIONS

The presence and extent of nonobstructive plaques augment prediction of incident mortality beyond conventional clinical risk assessment.

Prognostic value of CT angiography for major adverse cardiac events in patients with acute chest pain from the emergency department: 2-year outcomes of the ROMICAT trial

OBJECTIVES

The aim of this study was to determine the 2-year prognostic value of cardiac computed tomography (CT) for predicting major adverse cardiac events (MACE) in patients presenting to the emergency department (ED) with acute chest pain.

BACKGROUND

CT has high potential for early triage of acute chest pain patients. However, there is a paucity of data regarding the prognostic value of CT in this ED cohort.

METHODS

We followed 368 patients from the ROMICAT (Rule Out Myocardial Infarction Using Computer Assisted Tomography) trial (age 53 ± 12 years; 61% male) who presented to the ED with acute chest pain, negative initial troponin, and a nonischemic electrocardiogram for 2 years. Contrast-enhanced 64-slice CT was obtained during index hospitalization, and caregivers and patients remained blinded to the results. CT was assessed for the presence of plaque, stenosis (>50% luminal narrowing), and left ventricular regional wall motion abnormalities (RWMA). The primary endpoint was MACE, defined as composite cardiac death, nonfatal myocardial infarction, or coronary revascularization.

RESULTS

Follow-up was completed in 333 patients (90.5%) with a median follow-up period of 23 months. At the end of the follow-up period, 25 patients (6.8%) experienced 35 MACE (no cardiac deaths, 12 myocardial infarctions, and 23 revascularizations). Cumulative probability of 2-year MACE increased across CT strata for coronary artery disease (CAD) (no CAD 0%; nonobstructive CAD 4.6%; obstructive CAD 30.3%; log-rank p < 0.0001) and across combined CT strata for CAD and RWMA (no stenosis or RWMA 0.9%; 1 feature-either RWMA [15.0%] or stenosis [10.1%], both stenosis and RWMA 62.4%; log-rank p < 0.0001). The c statistic for predicting MACE was 0.61 for clinical Thrombolysis In Myocardial Infarction risk score and improved to 0.84 by adding CT CAD data and improved further to 0.91 by adding RWMA (both p < 0.0001).

CONCLUSIONS

CT coronary and functional features predict MACE and have incremental prognostic value beyond clinical risk score in ED patients with acute chest pain. The absence of CAD on CT provides a 2-year MACE-free warranty period, whereas coronary stenosis with RWMA is associated with the highest risk of MACE.

Computed tomography coronary angiography in the selection of outlier patients: a feasibility report

PURPOSE

This study evaluated criteria, presence and distribution of outlier patients by means of computed tomography coronary angiography (CTCA) in a large institutional database.

MATERIAL AND METHODS

From a population of 2,881 consecutive patients (1,842 men, mean age 62 ± 13 years) in sinus rhythm who underwent CTCA, we extracted data on patients with suspected coronary artery disease (CAD). We selected patient outliers in the fifth and sixth decades of life with the following criteria: ≥ 3 risk factors and absence of CAD, zero to one risk factors and ≥ 5 diseased coronary segments. Diabetes was excluded from risk factors because of the different impact on CAD.

RESULTS

The patient population consisted of 2,432 individuals with suspected CAD (1,495 men, age 62 ± 13 years). The prevalence of obstructive CAD (≥ 50% lumen reduction at CTCA) was 36% (863/2,432). Patients with normal coronary arteries accounted for 34% of the total (837/2,432; 431 men, age 55 ± 14 years). Of these, 210 were in the fifth and 231 in the 6th decade (men 196, women 245); those with ≥ 3 risk factors accounted for 4.2% of the total (102/2,432; men 42, women 60). Patients with ≥ 5 diseased coronary segments accounted for 28% of the total (686/2,432; 510 men, age 68 ± 10 years). Of these, 115 were in the fifth and 270 in the sixth decade (men 309, women 76); those with zero to one risk factors accounted for 3.0% (73/2,432; men 66, women 7).

CONCLUSIONS

CTCA is a reliable noninvasive diagnostic modality that can be used to identify outlier patients. This will enable dedicated trials aimed at characterising biomarkers and genomics of protective and nonprotective factors against CAD and its complications.

A prospective randomized controlled trial to assess the diagnostic performance of reduced tube voltage for coronary CT angiography

OBJECTIVE

Tube voltage reduction has been shown to be an effective method to reduce radiation dose in nonobese patients undergoing coronary CT angiography. To date, the impact of reduced tube voltage on objective measures of diagnostic accuracy, as defined by quantitative coronary angiography (QCA), has not been established. The purpose of this article was to investigate the impact of tube voltage reduction on the diagnostic performance of coronary CTA compared with QCA.

SUBJECTS AND METHODS

We performed a prospective randomized trial evaluating 50 consecutive patients referred for catheter angiography with a body mass index (BMI) ≤ 35 kg/m². Patients were randomly assigned to reduced (n = 24) or standard tube voltage (n = 26). Reduced tube voltage was defined as 80 or 100 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively; whereas standard tube voltage was defined as 100 or 120 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively. Tube current was fixed by study protocol as 600 mA (BMI < 30 kg/m²) or 650 mA (BMI ≥ 30 kg/m²). Coronary CTA examinations were interpreted by two blinded experienced readers with a third reader providing consensus. QCA was performed by an independent experienced core laboratory blinded to coronary CTA findings. Coronary artery segments were graded for stenosis as < 50%, 50-69%, and ≥ 70% by coronary CTA and as percentage stenosis by QCA. In an intention-to-diagnose fashion, all segments were included for final analysis, with nonevaluable segments by coronary CTA graded as obstructive. Signal and noise; contrast (mean signal-signal in left ventricular myocardium); and signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio were compared.

RESULTS

Mean age of the study cohort was 60.2 years; 78% were men. Prospective ECG gating was used in all patients, and no differences existed in scan length between groups (p = 0.19). Standard versus reduced tube voltage was associated with a reduction in effective radiation dose (2.6 ± 0.4 vs 1.3 ± 0.5 mSv, p < 0.001). The patient prevalence of luminal stenosis ≥ 50% was 56% (28/50). For detection of ≥ 50% stenosis in the standard versus reduced kVp groups, there were no differences in per-segment sensitivity (87% vs 84%, p = 0.73), specificity (92% vs 93%, p = 0.81), or accuracy (92% vs 91%, p = 0.70). No differences were noted for reduced versus standard tube current for SNR (13 ± 4 vs 13 ± 3, p = 0.59), CNR (10 ± 3 vs 10 ± 2, p = 0.99), or graded (0-4) image quality score (3.4 ± 0.8 vs 3.5 ± 0.6, p = 0.19).

CONCLUSION

Compared with standard tube voltage, coronary CTA using reduced tube voltage results in lower effective radiation dose with comparable diagnostic performance.

Influence of smoking on the prognostic value of cardiovascular computed tomography coronary angiography

AIMS

Computed tomography coronary angiography (CTA) is an important non-invasive imaging modality increasingly used for the diagnosis and prognosis of coronary artery disease (CAD). The purpose of the current study was to determine the influence of smoking status on the prognostic value of CTA in patients with suspected or known CAD.

METHODS AND RESULTS

In 1207 patients (57% male, age 57 ± 12 years) referred for CTA, the presence of significant CAD (≥ 50% stenosis) was determined. During follow-up (FU) the following events were recorded: all cause mortality, and non-fatal infarction. The prognostic value of CTA in smokers and non-smokers was compared using an interaction term in the Cox proportional hazard regression analysis. Significant CAD was observed in 327 patients (27%), and 273 patients (23%) were smokers. During a median FU time of 2.2 years, an event occurred in 50 patients. After correction for baseline characteristics including smoking in a multivariate model, significant CAD remained an independent predictor of events. Furthermore, a significant interaction (P < 0.05) was observed between significant CAD and smoking. The annualized event rate in smokers with significant CAD was 8.78% compared with 0.99% in smokers without significant CAD (P < 0.001). In non-smokers with significant CAD the annualized event rate was 2.07% compared with 1.01% in non-smokers without significant CAD (P= 0.058).

CONCLUSION

The prognostic value of CTA was significantly influenced by smoking status. The event rates in patients with significant CAD were approximately four-fold higher in smokers compared with non-smokers. These findings suggest that smoking cessation needs to be aggressively pursued, especially in smokers with significant CAD.

Incremental prognostic value of left ventricular function analysis over non-invasive coronary angiography with multidetector computed tomography

BACKGROUND

The purpose of this study was to determine the prognostic value of computed tomography coronary angiography (CTA)-derived left ventricular (LV) function analysis and to assess its incremental prognostic value over the detection of significant stenosis using CTA.

METHODS

In 728 patients (400 males, mean age 55 ± 12 years) with known or suspected CAD, the presence of significant stenosis (≥ 50% stenosis) and LV function were assessed using CTA. LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV), and LV ejection fraction (LVEF) were calculated. LV function was assessed as a continuous variable and using cutoff values (LVEDV > 215 mL, LVESV > 90 mL, LVEF < 49%). The following events were combined in a composite end-point: all-cause mortality, non-fatal myocardial infarction, and unstable angina pectoris requiring hospitalization.

RESULTS

On CTA, a significant stenosis was observed in 221 patients (30%). During follow-up [median 765 days, 25-75th percentile: 493-978] an event occurred in 45 patients (6.2%). After multivariate correction for clinical risk factors and CTA, LVEF < 49% and LVESV > 90 mL were independent predictors of events with an incremental prognostic value over clinical risk factors and CTA.

CONCLUSIONS

The present results suggest that LV function analysis provides independent and incremental prognostic information beyond anatomic assessment of CAD using CTA.

Incidence of subclinical coronary atherosclerosis in patients with suspected embolic stroke using cardiac computed tomography

The purpose of this study was to investigate the incidence of subclinical coronary artery disease (CAD) in patients with suspected acute embolic stroke or transient ischemic attack (TIA) using 64-row multi-slice computed tomography (MSCT) and to examine its association with conventional risk stratification. We consecutively enrolled 175 patients (66 ± 13 years, 50% men) suspected to have had embolic stroke/TIA clinically or radiologically, and underwent 64-row MSCT to evaluate for a possible cardiac source of embolism. Both coronary artery calcium scoring (CACS) and coronary CT angiography (CCTA) were concurrently performed based on standard scanning protocols. Patients with a history of angina or documented CAD, and those with significant carotid stenosis were excluded. Atherosclerotic plaques were indentified in 105 (60%) individuals; 37 (21%) had occult CAD of ≥50% diameter stenosis on CCTA. Subjects with and without ≥50% occult CAD on CCTA had similar prevalence of cardiovascular risk factors. Thirty out of 175 (17%) individuals with ≥50% occult CAD would have missed further cardiac testing based on the American Heart association and the American Stroke Association guideline. However, these numbers would be reduced to 2% (4/175) using CACS. In logistic regression analysis, only CACS independently predicted the presence ≥50% occult CAD evidenced by CCTA. Subclinical CAD, including ≥50% stenotic disease, is highly prevalent in patients who had suffered a suspected embolic stroke. The current guideline for further cardiac testing may have limited value to identify patients with ≥50% CAD in this patient population, which can be improved by adopting CACS.

Multislice CT angiography in coronary artery disease: Technical developments, radiation dose and diagnostic value

Multislice computed tomography (CT) angiography has been increasingly used in the detection and diagnosis of coronary artery disease because of its rapid technical evolution from the early generation of 4-slice CT scanners to the latest models such as 64-slice, 256-slice and 320-slice CT scanners. Technical developments of multislice CT imaging enable improved diagnostic value in the detection of coronary artery disease, and this indicates that multislice CT can be used as a reliable less-invasive alternative to invasive coronary angiography in selected patients. In addition, multislice CT angiography has played a significant role in the prediction of disease progression and cardiac events. Despite promising results reported in the literature, multislice CT has the disadvantage of having a high radiation dose which could contribute to the radiation-induced malignancy. A variety of strategies have been currently undertaken to reduce the radiation dose associated with multislice CT coronary angiography while in the meantime acquiring diagnostic images. In this article, the author will review the technical developments, radiation dose associated with multislice CT coronary angiography, and strategies to reduce radiation dose. The diagnostic and prognostic value of multislice CT angiography in coronary artery disease is briefly discussed, and future directions of multislice CT angiography in the diagnosis of coronary artery disease will also be highlighted.

The prognostic value of multidetector coronary CT angiography for the prediction of major adverse cardiovascular events: a multicenter observational cohort study

To assess the prognostic value of coronary artery stenosis identification by coronary computed tomographic angiography (CCTA) for the prediction of major adverse cardiac events (MACE) in a multicenter prospective cohort study. We performed a prospective multicenter observational cohort study of symptomatic patients with suspected or known coronary artery disease (CAD) (n = 172; 57% male) undergoing CCTA in accordance to ACC/AHA Appropriateness Criteria from 4 sites in and around Paris, France, and followed for a mean duration of 22.0 +/- 4.5 months (interquartile range 18-26 months). Coronary arteries by CCTA were interpreted by physicians blinded to the patient characteristics for the presence or absence obstructive (>or=70% luminal diameter stenosis), as well as for plaque composition categorized as non-calcified, calcified or "mixed." MACE was defined as death, non-fatal myocardial infarction, unstable angina or target vessel revascularization. MACE event rates were compared between patients with or without obstructive plaque and with differing plaque compositions. MACE event rates were significantly higher in patients with obstructive coronary artery stenosis by CCTA compared to those without (61.1% vs. 3.9%, P < 0.01). In patients with obstructive stenosis, mixed (83.3% vs. 25.3%, P < 0.01) and calcified (94.4% vs. 50.7%, P < 0.01) plaque presence was significantly higher than in patients without obstructive stenosis, with no differences in prevalence of non-calcified plaque (27.8% vs. 20.8%, P = NS). For MACE, the negative predictive value of no observed coronary artery plaque was 100% in the follow-up period. In this prospective multicenter study of symptomatic patients with suspected or known CAD undergoing CCTAs interpreted by imagers blinded to patient characteristics, CCTA presence of plaque severity and composition successfully identifies patients at risk for incident MACE events. Importantly, a negative CCTA portends an extremely low risk for incidence MACE.