Coronary Artery Computed Tomography Angiography Research Articles

A hybrid convolutional and transformer network for segmentation of coronary computed tomography angiographic slices

AbstractCoronary artery three‐dimensional reconstruction is essential for preventing, diagnosing, and treating coronary heart disease. This study introduces SegUnet, a lightweight hybrid CNN‐Transformer network for pixel‐level segmentation of coronary artery computed tomography angiography (CTA) slices to enhance the precision of coronary artery reconstruction. The overall SegUnet adopts a U‐shaped encoder‐decoder structure, with a hierarchical Transformer structure serving as the encoder to extract global contextual information; the decoder is enhanced with spatial attention mechanism (SAM) and residual structure to improve its perception and adaptive adjustment abilities for coronary artery vessels. In contrast to other methods, we propose an interpolation‐based multi‐feature fusion bridge to integrate multi‐scale features between encoder levels, capturing their semantic dependencies. Experimental results show that SegUnet achieves a prediction accuracy of 97.23% on the test set of coronary arteries 2D slices. Moreover, the network exhibits excellent performance on Synapse Multi‐Organ Segmentation, highlighting the superiority, effectiveness, and robustness of our proposed method. The outstanding performance of SegUnet in coronary artery segmentation has elevated the quality of three‐dimensional reconstruction of the coronary arteries, exerting a positive impact on the enhancement of diagnosis and treatment of coronary artery diseases.

Association between Major Adverse Cardiovascular Events and the Liver Fibrosis Score in Patients with and without Coronary Artery Disease: From the FU-CCTA Registry.

The liver fibrosis score reflects the degree of hepatic scarring and has been reported to be associated with cardiovascular disease. Using a coronary artery computed tomography angiography registry at the Fukuoka University Hospital (FU-CCTA registry), we investigated the association between major adverse cardiovascular events (MACEs) and the liver fibrosis score (fibrosis-4 index (FIB-4I)) in 612 patients who underwent CCTA to screen for coronary artery disease and performed a prognosis survey for up to 5 years. The primary endpoint was MACEs (all-cause mortality, acute myocardial infarction, ischemic stroke, coronary revascularization). FIB-4I in all patients and in patients with hypertension (HTN) was significantly higher in the MACE group than in the non-MACE group. The event-free survival rate of MACEs targeting only patients with HTN was significantly lower in patients with a high risk of liver fibrosis (FIB-4I values of 2.67 or higher) than in those with a low or intermediate risk (less than 2.67). However, no significant difference was observed in all patients or in patients without HTN. Finally, FIB-4I and body mass index were independent factors associated with MACEs in patients with HTN. In conclusion, the liver fibrosis score may be an independent predictor of MACEs in hypertensive patients undergoing CCTA.

A new predictor of coronary artery disease in acute ischemic stroke or transient ischemic attack patients: pericarotid fat density.

The study aims to evaluate the incremental predictive value of pericarotid fat density (PFD) on head and neck computed tomography angiography (CTA) for the obstructive coronary artery disease (CAD) (≥ 50% stenosis) relative to a clinical risk model (Framingham risk score (FRS)) and the degree of carotid artery stenosis and plaque type in acute ischemic stroke (AIS) or transient ischemic attack (TIA) patients without a known history of CAD. In a cohort of 134 consecutive stable patients diagnosed with AIS or TIA undergoing head and neck CTA between January 2010 and December 2021, pericarotid adipose tissue density (PFD) was quantified using a dedicated software. We collected demographic and clinical data, assessed the risk of CAD using the FRS, and analyzed coronary and carotid artery CTA images. Univariate and multivariate logistic regression analyses were performed to assess associations between FRS, PFD, CTA variables, and obstructive CAD risk. Four prediction models were established to evaluate the incremental predictive value of PFD relative to FRS, stenosis degree, and plaque types. Receiver operating characteristic (ROC) curves were generated, and the areas under the curves (AUC) were compared. Increasing FRS, stenosis degree, and PFD values were positively correlated with obstructive CAD (all p < 0.05). In the predictive models for obstructive CAD, the model incorporating carotid stenosis exhibited superior predictive performance compared to FRS alone (p < 0.05). Moreover, the predictive model integrating PFD demonstrated enhanced performance and yielded the highest AUC of the receiver operator characteristic curve (AUC = 0.783), with sensitivity and specificity values of 86.89% and 65.75%, respectively. CTA-derived PFD measurements offer supplementary predictive value for obstructive CAD beyond FRS and stenosis, thereby facilitating improved risk stratification of TIA or stroke patients without a history of CAD history. CTA-derived PFD provides incremental predictive value for obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients without CAD history, beyond Framingham risk score and carotid artery stenosis degree, improving risk stratification. • Pericarotid fat density is associated with obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients. • Higher pericarotid fat density corresponds to an increased risk of obstructive coronary artery disease. • Estimation of pericarotid fat density using computed tomography angiography imparts additional predictive value for obstructive CAD in risk stratification of acute ischemic stroke or transient ischemic attack patients.

Basing on the machine learning model to analyse the coronary calcification score and the coronary flow reserve score to evaluate the degree of coronary artery stenosis

AimTo obtain the coronary artery calcium score (CACS) for each branch in coronary artery computed tomography angiography (CCTA) examination combined with the flow fraction reserve (FFR) of each branch in the coronary artery detected by CT and apply a machine learning model (ML) to analyse and predict the severity of coronary artery stenosis. MethodsAll patients who underwent coronary computed tomography angiography (CCTA) from January 2019 to April 2022 in the HOSPITAL (T.C.M) AFFILIATED TO SOUTHWEST MEDICAL UNIVERSITY) were retrospectively screened, and their sex, age, characteristics of lipid-containing lesions, coronary calcium score (CACS) and CT-FFR values were collected. Five machine learning models, random forest (RF), k-nearest neighbour algorithm (KNN), kernel logistic regression, support vector machine (SVM) and radial basis function neural network (RBFNN), were used as predictive models to evaluate the severity of coronary stenosis. ResultsAmong the five machine learning models, the SVM model achieved the best prediction performance, and the prediction accuracy of mild stenosis was up to 90%. Second, age and male sex were important influencing factors of increasing CACS and decreasing CT-FFR. Moreover, the critical CACS value of myocardial ischemia >200.70 was calculated. ConclusionThrough computer machine learning model analysis, we prove the importance of CACS and FFR in predicting coronary stenosis, especially the prominent vector machine model, which promotes the application of artificial intelligence computer learning methods in the field of medical analysis.

Using a machine learning-based risk prediction model to analyze the coronary artery calcification score and predict coronary heart disease and risk assessment

ObjectivesTo calculate the coronary artery calcification score (CACS) obtained from coronary artery computed tomography angiography (CCTA) examination and combine it with the influencing factors of coronary artery calcification (CAC), which is then analyzed by machine learning (ML) to predict the probability of coronary heart disease(CHD). MethodsAll patients who were admitted to the Affiliated Hospital of Traditional Chinese Medicine of Southwest Medical University from January 2019 to March 2022, suspected of CHD, and underwent CCTA inspection were retrospectively selected. The degree of CAC was quantified based on the Agatston score. To compare the correlation between the CACS and clinical-related factors, we collected 31 variables, including hypertension, diabetes, smoking, hyperlipidemia, among others. ML models containing the random forest (RF), radial basis function neural network (RBFNN),support vector machine (SVM),K-Nearest Neighbor algorithm (KNN) and kernel ridge regression (KRR) were used to assess the risk of CHD based on CACS and clinical-related factors. ResultsAmong the five ML models, RF achieves the best performance about accuracy (ACC) (78.96%), sensitivity (SN) (93.86%), specificity(Spe) (51.13%), and Matthew's correlation coefficient (MCC) (0.5192).It also has the best area under the receiver operator characteristic curve (ROC) (0.8375), which is far superior to the other four ML models. ConclusionComputer ML model analysis confirmed the importance of CACS in predicting the occurrence of CHD, especially the outstanding RF model, making it another advancement of the ML model in the field of medical analysis.

Coronary Artery Computed Tomography Angiography for Preventing Cardio-Cerebrovascular Disease: Observational Cohort Study Using the Observational Health Data Sciences and Informatics' Common Data Model.

BackgroundCardio-cerebrovascular diseases (CVDs) result in 17.5 million deaths annually worldwide, accounting for 46.2% of noncommunicable causes of death, and are the leading cause of death, followed by cancer, respiratory disease, and diabetes mellitus. Coronary artery computed tomography angiography (CCTA), which detects calcification in the coronary arteries, can be used to detect asymptomatic but serious vascular disease. It allows for noninvasive and quick testing despite involving radiation exposure.ObjectiveThe objective of our study was to investigate the effectiveness of CCTA screening on CVD outcomes by using the Observational Health Data Sciences and Informatics’ Observational Medical Outcomes Partnership Common Data Model (OMOP-CDM) data and the population-level estimation method.MethodsUsing electronic health record–based OMOP-CDM data, including health questionnaire responses, adults (aged 30-74 years) without a history of CVD were selected, and 5-year CVD outcomes were compared between patients undergoing CCTA (target group) and a comparison group via 1:1 propensity score matching. Participants were stratified into low-risk and high-risk groups based on the American College of Cardiology/American Heart Association atherosclerotic cardiovascular disease (ASCVD) risk score and Framingham risk score (FRS) for subgroup analyses.ResultsThe 2-year and 5-year risk scores were compared as secondary outcomes between the two groups. In total, 8787 participants were included in both the target group and comparison group. No significant differences (calibration P=.37) were found between the hazard ratios of the groups at 5 years. The subgroup analysis also revealed no significant differences between the ASCVD risk scores and FRSs of the groups at 5 years (ASCVD risk score: P=.97; FRS: P=.85). However, the CCTA group showed a significantly lower increase in risk scores at 2 years (ASCVD risk score: P=.03; FRS: P=.02).ConclusionsAlthough we could not confirm a significant difference in the preventive effects of CCTA screening for CVDs over a long period of 5 years, it may have a beneficial effect on risk score management over 2 years.

Congenital Anomalous Origin of Coronary Artery Disease in Children With Syncope: A Case Series.

ObjectiveThis study is aimed to analyze the characteristics of congenital anomalous origin of coronary artery in pediatric patients with syncope.MethodsA total of eight patients were retrospectively analyzed from August 2018 to August 2020 who were admitted to the Peking University First Hospital with the complaint of syncope and were diagnosed with congenital coronary artery disease.ResultsIn total, eight patients were included in the study with a median age of 12.5 ± 2.7 (8–16) years. In total, four of them were males, and four were females. Six of the eight patients were diagnosed with right anomalous coronary artery from the opposite sinus (R-ACAOS), while two patients were diagnosed with left anomalous coronary artery from the opposite sinus (L-ACAOS). The most frequent inducement was exercise, and the commonest prodromes were dizziness and blurred vision. Serum cardiac markers and exercise electrocardiography test (EET) were normal in seven of the patients. The majority of cases had abnormal electrocardiograms (ECGs), but only two of them manifested elevated/depressed ST-T segments. In total, seven patients had positive head-up tilt test (HUT). Echocardiography and coronary artery computed tomography angiography (CTA) were performed to aid the diagnosis. Coronary unroofing procedures were conducted in four patients, and none of them reported syncope after the surgery. The other four patients received routine medical treatment for vasovagal-like syncope. In total, two patients out of them became asymptomatic, and in the other two patients, episodes of syncope were reduced, but they still required medical treatment.ConclusionCongenital coronary artery anomalies in children with syncope need prompt attention. Though ECG and echocardiography are the common methods for investigating cardiac syncope, they have limited ability to find coronary artery anomalies. When coronary artery anomalies are suspected, coronary CTA should be considered.

Characteristics of coronary artery disease in patients with subclinical hypothyroidism: evaluation using coronary artery computed tomography angiography

BackgroundSubclinical hypothyroidism (SCH) has recently been acknowledged as an independent risk factor for coronary artery disease (CAD). However, the characteristics of CAD in patients with SCH are not fully understood. This study aims to evaluate the features of CAD in patients with SCH using coronary computed tomographic angiography (CCTA).Materials and methodsFrom 1 April, 2018 to 30 June, 2020, 234 consecutive SCH patients with coronary plaques identified on CCTA were included retrospectively. They were further subdivided into different degree of SCH groups (mild SCH vs. moderate SCH vs. severe SCH: 143 vs 62 vs 28) and different gender groups (men with SCH vs. women with SCH:116 vs 118). The distributions and types of plaques, luminal narrowing, segment involvement scores (SIS) and segment stenosis scores (SSS) were evaluated and compared among the different groups.ResultsPatients with severe SCH had fewer calcified plaques (0.7 ± 0.9 vs. 2.0 ± 1.9, p < 0.001) and more non-calcified plaques (0.9 ± 1.0 vs. 0.3 ± 0.5, p < 0.001) than those with mild SCH. As the SCH condition worsened, the proportion of non-calcified plaques significantly increased. Whereas there were no significant discrepancies in SIS and SSS among patients with different grades of SCH (all p > 0.05). Men with SCH had higher SIS (3.9 ± 2.3 vs. 3.0 ± 2.3, p = 0.004) and SSS (7.8 ± 5.4 vs. 5.4 ± 3.0, p = 0.002) than women. Multivariate logistic and linear regression analysis demonstrated that grades of SCH (Moderate SCH, odds ratio [OR] 2.11; 95% CI 1.03–4.34, p = 0.042; severe SCH, OR: 10.00; 95% CI 3.82–26.20, p < 0.001, taken mild SCH as a reference) was independently associated with the presence of non-calcified plaques, whereas sex (B: 1.67; 95% CI 0.27–3.10, p = 0.009) was independently associated with SSS.ConclusionsSevere SCH is associated with non-calcified plaques, and men with SCH have higher total plaque burden than women. We suggest that it is important to evaluate for coronary plaque in SCH patients, especially those with severe SCH and men with SCH.

Anatomical correlation between left atrium pulmonary vein ablation targets of atrial fibrillation and adjacent bronchi and pulmonary arteries by MSCT

BackgroundThe ablation targets of atrial fibrillation (AF) are adjacent to bronchi and pulmonary arteries (PAs). We used computed tomography (CT) to evaluate the anatomical correlation between left atrium (LA)-pulmonary vein (PV) and adjacent structures.MethodsData were collected from 126 consecutive patients using coronary artery CT angiography. The LA roof was divided into three layers and nine points. The minimal spatial distances from the nine points and four PV orifices to the adjacent bronchi and PAs were measured. The distances from the PV orifices to the nearest contact points of the PVs, bronchi, and PAs were measured.ResultsThe anterior points of the LA roof were farther to the bronchi than the middle or posterior points. The distances from the nine points to the PAs were shorter than those to the bronchi (5.19 ± 3.33 mm vs 8.62 ± 3.07 mm; P < .001). The bilateral superior PV orifices, especially the right superior PV orifices were closer to the PAs than the inferior PV orifices (left superior PV: 7.59 ± 4.14 mm; right superior PV: 4.43 ± 2.51 mm; left inferior PV: 24.74 ± 5.26 mm; right inferior PV: 22.33 ± 4.75 mm) (P < .001).ConclusionsThe right superior PV orifices were closer to the bronchi and PAs than other PV orifices. The ablation at the mid-posterior LA roof had a higher possibility to damage bronchi. CT is a feasible method to assess the anatomical adjacency in vivo, which might provide guidance for AF ablation.

Comparative effectiveness of coronary screening in heart valve surgery: Computed tomography versus conventional coronary angiography

BackgroundAlthough conventional coronary angiography (CAG) is considered the gold standard for coronary artery disease (CAD) screening in the setting of heart valve surgery, coronary artery computed tomography angiography (CCTA) has emerged as an alternative modality. This study was conducted to evaluate the clinical outcomes of CCTA compared with conventional CAG for CAD screening in patients undergoing heart valve surgery. MethodsA total of 3150 consecutive patients aged >40 years or with coronary risk factors undergoing elective valve operations between 2001 and 2015 were evaluated. Of these, 1402 patients underwent CCTA (CT group) and 1748 patients underwent conventional CAG (CAG group) for CAD screening. ResultsThe 30-day mortality rates were similar in the 2 groups (2.1% in the CT group vs 1.7% in the CAG group; P = .463); however, the incidence of low cardiac output syndrome was higher in the CT group (2.3% vs 1.0%; P = .008). The final rate of detection of significant CAD (≥50% stenosis) (4.9% vs 9.7%; P < .001) and proportion of receiving coronary bypass grafting (CABG) (2.9% vs 4.3%; P = .041) were lower in the CT group. After adjustment by propensity score matching (563 pairs), the main findings of our crude analyses did not change, with lower rates of CAD detection (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.36-0.85) and CABG (OR, 0.47; 95% CI, 0.26-0.81), a similar risk of early mortality (OR, 1.51; 95% CI, 0.54-4.52), but a higher risk of low cardiac output syndrome (OR, 3.30; 95% CI, 1.16-11.78) in the CT group compared with the CAG group. ConclusionsThe detection of significant CAD and identification of candidates for CABG were inferior with CCTA compared with conventional CAG in patients scheduled for elective heart valve operations.

Impact of advanced modeled iterative reconstruction on interreader agreement in coronary artery measurements

ObjectivesTo evaluate the influence of advanced modeled iterative reconstruction (ADMIRE) on coronary artery computed tomography angiography (cCTA) measurements in comparison to filtered back projection (FBP). Material and methodsPhantom scans and coronary CTA studies of 27 patients were acquired with a third generation dual-source CT scanner. Images were reconstructed using FBP and ADMIRE. Phantom measurements were used as reference standard. In patient studies, representative axial slices of each coronary artery segment without (n=308) and with coronary plaques (n=40) were assessed in identical positions for comparison of FBP and ADMIRE reconstructions. Image analyses included quality assessment, phantom and coronary artery measurements, plaque analysis, and interreader agreement of two independent and blinded readers. ResultsMean image noise was lower on ADMIRE reconstructions with 31.3±9.9 HU compared to 55.9±15.7 HU on FBP reconstructions (p<0.001). Measurement precision and interreader agreement of both observers were assessed satisfactorily on phantom images in comparison to the full width half maximum method. In patients, correlation of lumen diameters of both observers improved using ADMIRE with a Pearson’s r=0.987 (95% confidence interval [CI], 0.983–0.989; p<0.001) compared to FBP images with r=0.939 (95% CI, 0.924–0.951; p<0.001). Applying ADMIRE, agreement of both observers for lumen diameter measurements significantly increased (p<0.001). This was also observed for the degree of stenosis (p<0.001) with r=0.560 using FBP (95% CI, 0.301–0.742) and with r=0.818 using ADMIRE (95% CI, 0.680–0.900). Plaque density measurements correlated closely with a Pearson’s r of 0.951 in FBP (95% CI, 0.909–0.974) and 0.967 in ADMIRE (95% CI, 0.939–0.983). ConclusionsAdvanced modeled iterative reconstruction significantly improves coronary artery assessment in coronary CTA in comparison to FBP by improved image quality due to image noise removal. This renders improved interobserver agreement for coronary lumen diameter and degree of stenosis measurements without influencing mean plaque attenuation.

Morphological features of the left atrial appendage in consecutive coronary computed tomography angiography patients with and without atrial fibrillation.

The majority of intracardiac thrombi form in the left atrial appendage (LAA). Enlargement of this structure, together with certain morphological features, may indicate a predisposition to the formation of thrombi and subsequent cardioembolic stroke. Thus far, studies on LAA morphology have largely focused on those patients with atrial fibrillation (AF). Taking a different approach, we investigated the variation in LAA morphology in a consecutive patient population with and without AF. We evaluated 808 consecutive patients (529 females; mean age 52.5±9.9 years) who underwent coronary artery computed tomography angiography (CCTA), the majority of whom (749) had no history of AF. We assessed the length, lobe number, and morphological classification of their LAAs. Demographic data and medical histories were collated from medical records and then correlated with LAA morphology. The proportions of each of the four morphological classes of LAA for the overall vs. non-AF population were: WindSock, 62.3/61.5%; Cactus, 18.6/18.8%; ChickenWing, 10.0/10.0%; and CauliFlower, 9.2/9.6%. Age (p<0.001; r = 0.156) and female gender (p<0.001) were both found to be associated with an increased body surface area (BSA)-related LAA length. Male patients were more likely to manifest multi-lobed (p = 0.003) LAAs, and overweight patients with a greater number of multi-lobed LAA morphological classes (p = 0.010). No associations with morphological LAA features could be found for patients with diabetes, hypertension, or dyslipidemia. Nor did the size of the left atrium exhibit any correlation with BSA-related LAA length. In the overall and non-AF populations, aging and female gender were associated with longer BSA-indexed LAAs.

Effect of Coronary Artery Calcification Score by Lifestyle and Correlation With Coronary Artery Stenosis by Multidetector Computed Tomography.

This study examined the effect of coronary artery calcification score by lifestyle and correlation with coronary artery stenosis in persons who underwent coronary artery computed tomography (CT) angiography among health examinees for heart diseases in Korea. The study included 506 subjects (256 men and 250 women) who underwent coronary artery CT angiography among health examines for heart diseases at the Incheon Branch of the Korea Association of Health Promotion between January 2, 2014, and December 31, 2014. The demographical variables of the subjects were determined by frequency analysis, and the difference by sex was compared and analyzed using χ independence test. Independent 2-sample t test was performed to determine any difference in main factors by coronary artery calcification. According to the results, 175 (34.6%) had calcification, men showed statistically higher scores than women, and calcification seemed higher in those who were older, taller, heavier, and thicker in waist. Regarding blood pressure, calcification was shown if contraction phase and relaxation blood pressure was higher, blood sugar before meal was higher, and neutral fat was higher. By lifestyle, calcification seemed to be higher in those with more alcohol drinking per week, long past smoking years, and higher smoking amount per day in the past and present. In addition, coronary artery stenosis rate showed statistical correlation with calcification from the left anterior descending artery, right coronary artery, left circumflex artery, and left main coronary artery in sequence. In conclusion, coronary artery calcification score CT is deemed to be a suitable method for the estimation of coronary artery stenosis with short examination time, low radiation exposure, and noninvasive method.

320-row-detector CT angiography findings in a case with myocardial bridging in the three main coronary arteries.

A 46-year-old man with the complaining of palpitation was admitted to our hospital. Polymorphic ventricular early beats were observed on electro cardiography, The patient was referred to our department for coronary artery computed tomography angiography (CTA) for a probable congenital anomaly. On coronary CTA performed by a 320-Row-Detector scanner; left main coronary artery was short. The myocardial bridging (MB) causes approximately 75% luminal stenosis in a 2.5-cm segment was observed in the middle segment of left anterior descending artery (Fig. A, white arrow). The circumflex artery was continuing as the first obtus margin artery and this branch was separating to four branches in the middle part. All of these branches were coursing subepicardially in the middle and distal part (Fig. B, white arrowheads). The right main coronary artery was separating to two branches in the proximal part, and the thinner one was showing MB in its middle part (Fig. C, black arrow). This branch had a subepicardial course as well, in its distal part along the right atrium (Fig. C, black arrowheads). Eventually, all the cardiologic examinations and imaging findings were reevaluated. Based on those findings, antiarrhythmic drug therapy was prescribed by cardiology department, and the patient was called for regular follow-up.

Upward Displacement of Prosthetic Aortic Valved Conduit after Modified Bentall Procedure for Type A Acute Aortic Dissection

Aim: Role of non-invasive coronary artery computed tomography (CACT) in diagnosis of complications of aortic root surgery in patients with chest pain. Introduction: Dehiscence of an aortic valved conduit or pseudoaneurysm development is a rare, but serious and potentially life-threatening complication after aortic root surgery. Case Presentation: We report an interesting case of a 61-year-old man with chest pain and dyspnea, previous history of modified Bentall procedure for type A acute aortic dissection and coronary stenting, that shows a complete detachment and upward displacement of a composite tubular graft with mechanical valve prosthesis detected by a CACT angiography. Discussion: Generally, in the few survivors, the diagnosis is made by means of echocardiography. This is the first case of CACT diagnosis of a prosthetic aortic valved conduit displacement after a

Value of dual-source computed tomography angiography of coronary artery for preoperative evaluation of old patients scheduled for noncardiac surgery

To assess the role of computed tomography angiography (CTA) using dual-source computed tomography in the preoperative evaluation of old patients scheduled for noncardiac surgery. A retrospective review of the clinical data of patients who underwent CTA in our hospital between May 2011 and May 2013 was performed, and totally 111 old patients with risk factors of coronary artery diseases scheduled for noncardiac surgery were found to coronary CTA for preoperative evaluation. Prospectively electrocardiograph-triggered sequence scan protocol with dual-source computed tomography was performed. The imaging quality, coronary artery stenosis, the treatment before operation, and perioperative complications were assessed. For 1 779 coronary artery segments in 111 patients, the number of evaluable segments was 1 676 (97.4%). The mean effective dose of CTA was (2.7 ± 0.9) mSv. Among them, 71 patients with coronary artery stenosis <50% underwent surgery without cardiac complication and 17 patients with coronary artery stenosis ≥ 70% underwent conventional coronary angiography and coronary angioplasty or bypass surgery. The sensitivity and specificity of CTA in detecting ≥ 50% stenosis were 95% and 96%, and the sensitivity and specificity of CTA in detecting ≥ 70% stenosis were 97% and 98%. For 19 patients with coronary artery stenosis between 50% and 70%, the levels of myocardial enzyme were transiently higher for two patients, and no other cardiac complication occurred. Coronary artery CTA is reliable in artery stenosis evaluation and can be used as cardiac risk stratification for old patients scheduled for noncardiac surgery.

151 Prevalence of Coronary Artery Disease and Major Adverse Cardiovascular Events in Patients with A Zero Calcium Score: A Prospective Cardiac CT Study

IntroductionCardiac computed tomography (CT), consisting of coronary artery calcium (CAC) scoring and CT angiography (CTa), is recommended by NICE for the exclusion of coronary artery disease (CAD) in intermediate-risk symptomatic...

Reconstructions with identical filling (RIF) of the heart: a physiological approach to image reconstruction in coronary CT angiography

To compare image quality in coronary artery computed tomography angiography (cCTA) using reconstructions with automated phase detection and Reconstructions computed with Identical Filling of the heart (RIF). Seventy-four patients underwent ECG-gated dual source CT (DSCT) between November 2009 and July 2010 for suspected coronary heart disease (n = 35), planning of transcatheter aortic valve replacement (n = 34) or evaluation of ventricular function (n = 5). Image data sets by the RIF formula and automated phase detection were computed and evaluated with the AHA 15-segment model and a 5-grade Likert scale (1: poor, 5: excellent quality). Subgroups regarding rhythm (sinus rhythm = SR; arrhythmia = ARR) and potential premedication were evaluated by a per-segment, per-vessel and per-patient analysis. RIF significantly improved image quality in 10 of 15 coronary segments (P < 0.05). More diagnostic segments were provided by RIF regarding the entire cohort (n = 693 vs. 590, P < 0.001) and all of the subgroups (e.g. ARR: n = 143 vs. 72, P < 0.001). In arrhythmic patients (n = 19), more diagnostic vessels (e.g. LAD: n = 10 vs. 3; P < 0.014) and complete data sets (n = 7 vs. 1; P < 0.001) were produced. RIF reconstruction is superior to automatic diastolic non-edited reconstructions, especially in arrhythmic patients. RIF theory provides a physiological approach for determining the optimal image reconstruction point in ECG-gated CT angiography. Conventional CT coronary angiography suffers from numerous artefacts in patients with irregular rhythms. Coronary computed tomography angiograms (cCTA) were reconstructed with identical cardiac filling (RIF). RIF reconstructions provide improved image quality compared to non-edited standard reconstructions. RIF theory links physiology with cardiac CT.

Tachycardia during Coronary Computed Tomography Angiography

A 76-year-old woman underwent a coronary artery computed tomography angiography (CTA) to exclude coronary occlusive disease after a segmental inferoseptal hypokinesia was discovered at echocardiography in the workup for atypical chest pain. The patient has a body mass index of 40 kg/m2, a history of arterial hypertension, hyperlipidemia, hypothyroidism, and type 2 diabetes. Her drug regimen consists of acenocoumarol, bisoprolol, potassium canrenoate, simvastatin, levothyroxine, and metformin. She also has a history of a second-degree type I atrioventricular block found 18 years earlier during an episode of atrial fibrillation (AF) that has led to several syncopes. A Topaz II pacemaker (Vitatron, Maastricht, the Netherlands) was implanted 10 years ago, replaced 1 year ago, with preservation of the lead, by a Zephyr SR 5620 pacemaker (St. Jude Medical, St. Paul, MN, USA) in the ventricular rate modulated pacing (VVIR mode). The pacemaker control examinations 10 days prior and 6 months after CTA showed a normally functioning stimulator with a virtually permanent ventricular pacing and no alert between both examinations. Stimulation (0.75 then 0.75 V) and sensing (9.6 then 9.3 mV) thresholds and lead impedance (827 then 848 ohms) were within normal ranges and relatively unchanged between both examinations. The activity sensor was turned “on” and the maximum sensor rate was set at 130 beats per minute (bpm). Reaction time was tuned to “fast” and recovery time to “medium.” Stimulation was programmed in the unipolar mode and sensing in the bipolar mode. Battery voltage was 2.79 V with an estimated remaining life of more than 7 years. The 64-row multidetector LightSpeed VCT XT scanner (General Electric, Fairfield, CT, USA)

Absolute Coronary Artery Calcium Scores are superior to MESA percentile rank in predicting obstructive coronary artery disease

Coronary artery calcium scoring (CAC) is an excellent non-invasive method to evaluate coronary atherosclerotic burden. To better predict the risk of future events in an individual, their absolute CAC score is compared to an age- and gender-matched cohort in order to assign a percentile rank. However, it is unknown whether absolute CAC or percentile rank is better in predicting obstructive coronary artery disease (CAD). We hypothesized that absolute CAC is superior to percentile rank in predicting obstructive CAD. 210 consecutive patients referred to our institution for CAC and coronary artery computed tomography angiography (CTA) were included. CAC scores were expressed as Agatston score; percentile rank as published by the Multi-Ethnic Study of Atherosclerosis. Coronary artery stenoses were graded semi-quantitatively. Receiver operating characteristics curves (ROC) were used to assess the performance of CAC to predict obstructive CAD. In the overall group, the area under the curve (AUC) was significantly greater for absolute CAC compared to MESA percentile rank in predicting obstructive CAD (0.80 vs. 0.72, P = 0.006). Subgroup analysis revealed similar findings: AUC for absolute CAC was greater than for MESA percentile rank in males (0.82 vs. 0.71, P = 0.008), females (0.78 vs. 0.72, P = 0.085), symptomatic patients (0.78 vs. 0.72, P = 0.067) and in asymptomatic subjects (0.89 vs. 0.74, P = 0.05). Absolute CAC is superior to MESA percentile rank in predicting obstructive CAD. This finding was seen in both symptomatic and asymptomatic patients as well as in males and females.