Conventional Invasive Coronary Angiography Research Articles

Simultaneous Viability Assessment and Invasive Coronary Angiography Using a Therapeutic CT System in Chronic Myocardial Infarction Patients.

In a preclinical study using a swine myocardial infarction (MI) model, a delayed enhancement (DE)-multi-detector computed tomography (MDCT) scan was performed using a hybrid system alongside diagnostic invasive coronary angiography (ICA) without the additional use of a contrast agent, and demonstrated an excellent correlation in the infarct area compared with histopathologic specimens. In the present investigation, we evaluated the feasibility and diagnostic accuracy of a myocardial viability assessment by DE-MDCT using a hybrid system comprising ICA and MDCT alongside diagnostic ICA without the additional use of a contrast agent. We prospectively enrolled 13 patients (median age: 67 years) with a previous MI (>6 months) scheduled to undergo ICA. All patients underwent cardiac magnetic resonance (CMR) imaging before diagnostic ICA. MDCT viability scans were performed concurrently with diagnostic ICA without the use of additional contrast. The total myocardial scar volume per patient and average transmurality per myocardial segment measured by DE-MDCT were compared with those from DE-CMR. The DE volume measured by MDCT showed an excellent correlation with the volume measured by CMR (r=0.986, p<0.0001). The transmurality per segment by MDCT was well-correlated with CMR (r=0.900, p<0.0001); the diagnostic performance of MDCT in differentiating non-viable from viable myocardium using a 50% transmurality criterion was good with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 87.5%, 99.5%, 87.5%, 99.5%, and 99.1%, respectively. The feasibility of the DE-MDCT viability assessment acquired simultaneously with conventional ICA was proven in patients with chronic MI using DE-CMR as the reference standard.

Comprehensive Assessment of Myocardial Ischemia Mechanisms in the Catheterization Laboratory: Design and Rationale of the Advanced Invasive Diagnosis Strategy for Patients with Stable Coronary Syndromes Undergoing Coronary ANGIOgraphy - the AID-ANGIO Study

BackgroundThe diagnostic yield of invasive coronary angiography (ICA) to identify obstructive coronary artery disease in the context of chronic coronary syndromes (CCS) is very low. Furthermore, myocardial ischemia may have a non-obstructive origin, which cannot be detected by ICA. MethodsAID-ANGIO is an observational, prospective, single-cohort, multicenter study, intended to evaluate the diagnostic yield of adopting a hierarchical strategy to assess obstructive and non-obstructive causes of myocardial ischemia in an all-comers population of patients with CCS at the time of ICA. The primary endpoint will investigate the additional diagnostic value of such strategy over angiography alone regarding the identification of ischemia-generating mechanisms. SummaryAn estimated sample of consecutive 260 patients with CCS referred by their clinicians to ICA, will be enrolled. In a stepwise manner, a conventional ICA will be performed as the initial diagnostic tool. Those patients with severe-grade stenosis will not undergo further assessment and an obstructive origin for myocardial ischemia will be assumed. Subsequently, the remainder with intermediate-grade stenosis will be assessed with pressure guidewires. Those with a negative result from physiological evaluation and those without epicardial coronary stenosis will be further studied for ischemia of non-obstructive origin, including microvascular dysfunction and vasomotor disorders.The study will be conducted in two steps. Firstly, ICA images will be displayed to patient's referring clinicians, who will be asked to identify the existent epicardial stenosis, their angiographic severity and probable physiological relevance, together with a tentative therapeutic approach. Then, the diagnostic algorithm will continue to be applied and, considering the whole gathered information, a definite therapeutic plan will be consensually established by the interventional cardiologist and patient's referring clinicians. ConclusionThe AID-ANGIO study will assess the additional diagnostic yield of a hierarchical strategy over ICA alone to identify ischemia-generating mechanisms in patients with CCS and its impact on therapeutic approach. Positive results of the study might support a streamlined invasive diagnostic process for patients with CCS.

Role of MDCT in Assessment of Long-term Graft Patency in Female Patients

Objectives: The aim of the study was to analyze the utility of CT-coronary angiogram (CT-CAG) in assessment of long-term graft patency compared to conventional invasive coronary angiography (ICA) and highlight any gender-specific issues in female post-coronary artery bypass surgery (CABG) patients. Materials and Methods: The medical records and images of 30 patients including four female patients who had CABG in the past and underwent both conventional and CT-CAGs were analyzed retrospectively. Results: We studied 30 patients who had CABG in whom both CT-CAG and conventional coronary angiograms were performed. CT-CAG was able to evaluate the grafts better than ICA and was useful even in those which could not be assessed due to technical failure by ICA. There were only four female patients in this series. In first patient, the arterial graft (left internal mammary artery [LIMA]) was patent but distal run off was absent in LAD in CT-CAG images and was reported as poor in conventional coronary angiogram. The second patient had CABG 10 years back. The arterial graft (LIMA) to LAD was patent and there was total block in SVG graft to RCA at proximal anastomotic site. The third patient with hypertension and diabetes also had CABG 10 years back. Both LIMA to LAD and SVG to PDA were patent in her. In last case who had CABG 7 years, two of the three SVG grafts were blocked which were well-demonstrated on CT CAG, including one SVG missed on conventional CAG. Conclusion: CT-CAG is a non-invasive and less cumbersome alternative to conventional CAG for the assessment of grafts long after CABG even in women. The data generated by CT-CAG in post-CABG are as good as the invasive CAG and it has distinct advantage of greater acceptability.

Abstract 10954: Quantification of Myocardial Perfusion Reserve Using a Cardiac-Centered Camera: First Comparison with Invasive Indexes of Coronary Microvascular Disease

Introduction: – The invasive quantification of coronary flow reserve (CFR), the index of microcirculatory resistance (IMR), and fractional flow reserve (FFR) allows to assess coronary physiology. Although semi-conductor (CZT) SPECT myocardial perfusion reserve (MPR) has been previously compared with FFR, there are no data documenting the relationships between CZT SPECT MPR on one hand and CFR and/or IMR on the other hand. We assessed the performances of noninvasive CZT SPECT MPR in comparison with invasively determined FFR, CFR, and IMR. Methods: – Rest and dipyridamole-induced stress myocardial blood flow and MPR were quantified using 99m Tc-SestaMIBI and a Discovery NM 530c camera in 26 patients with suspected or known coronary artery disease who underwent conventional invasive coronary angiography. Thermodilution-derived resting and adenosine-induced hyperemic mean transit times, distal intracoronary pressures, and mean aortic pressures were assessed for the quantification of FFR, CFR, and IMR values. Results: – Only 2/35 vessels presented with a pathological (&lt;0.8) FFR. A moderate yet significant correlation was observed between regional CZT SPECT MPR and CFR (r=0.40, P =.02). The sensitivity, specificity, positive and negative predictive value, and accuracy of regional CZT SPECT MPR vs CFR were 69% [44-86%], 94% [74-100%], 91% [65-100%], 77% [56-90%], and 82% [65-93%], respectively. In territories without underlying CAD (n=32), CZT SPECT MPR values were significantly higher in those with CFR≥2 and IMR&lt;25 (negative composite criterion, n=14) than in those with CFR&lt;2 and IMR≥25 (positive composite criterion, n=8, CZT SPECT MPR, 2.6 [2.1-3.6] vs 1.6 [1.2-1.8]), P &lt;.01). Regional CZT SPECT MPR displayed sensitivity, specificity, positive and negative predictive value, and accuracy of 87% [53-99%], 100% [78-100%], 100% [64-100%], 93% [70-99%], and 95% [77-99%] for the diagnosis of a positive composite criterion, respectively. Conclusions: – CZT SPECT MPR presented a moderate, significant correlation with thermodilution CFR and good diagnostic performances for the detection of patients at high risk of cardiovascular events (low CFR and high IMR) in the absence of obstructive CAD.

Regadenoson Mycardial Contrast Echocardiography Perfusion Imaging for Detection of Allograft Coronary Vasculopathy

<h3>Purpose</h3> Due to the often asymptomatic nature of cardiac allograft vasculopathy (CAV) serial surveillance is recommended for all cardiac transplant (OHT) recipients. Ideally, CAV surveillance should be non-invasive, not involve ionizing radiation, and discriminate diffuse CAV from focal obstructions. We hypothesized that vasodilator stress myocardial contrast echocardiography (MCE) perfusion imaging can non-invasively detect microvascular impact of diffuse or focal CAV. <h3>Methods</h3> The study was a retrospective, single center analysis of OHT recipients undergoing MCE between 1/20 and 10/20 (n=11). MCE at rest and after regadenoson was performed using a continuous infusion of lipid-shelled microbubbles. Images were analyzed by evaluating time-intensity after a destructive pulse sequence in all vascular territories. MCE data were correlated with wall motion assessment by conventional stress echocardiography and invasive coronary angiography (ICA). Grading of MCE as normal, mild, severe; and focal vs. diffuse was performed by one experienced reviewer in a blinded fashion. <h3>Results</h3> Mean age was 63 ± 3.3 years post OHT, at an average of 10.8 ± 3.3 years post OHT. Severe perfusion abnormalities during MCE were able to distinguish high grade CAV (2+) from low grade CAV (0-1) utilizing ICA as the gold standard. While stress echocardiographic wall motion assessment failed to indicate early CAV grade 1, abnormal MCE perfusion was found in 3 of 7 cases with angiographic CAV grade 1. <h3>Conclusion</h3> MCE is a practical, non-invasive perfusion imaging technique that may be useful for detecting significant CAV in OHT recipients. Perfusion deficits correlate with significant coronary artery stenosis identified by standard stress echocardiography and ICA, and may identify diffuse small vessel disease more effectively than current noninvasive techniques. Larger, prospective studies are needed to support this hypothesis and ultimately provide a rationale for routine use of MCE for CAV surveillance.

Diagnostic value of intraluminal stent enhancement in estimating coronary in-stent restenosis.

Objective:In-stent restenosis (ISR) diagnosis is among the most serious complications of patients undergone stent implantation. Although coronary computed tomography angiography (CCTA) has been widely used for ISR assessing, stent narrow lumen and presence of stent’s struts artifacts have limited its efficacy. The use of quantitative techniques may provide more valuable findings for ISR diagnosis. The aim of this study is to assess the predictive value of a quantitative technique of ISR estimation based on stent intraluminal enhancement derived from CCTA.Materials and Methods:In the current study, 40 patients with the previous history of coronary artery diseases (CADs) and coronary stent placement who reexperienced CAD symptoms and referred for CCTA were assessed in 2017–2018. Stent intraluminal “enhancement value” (EV) was measured using calcium score and post-contrast images of CCTA. The cutoff point was determined using conventional invasive coronary angiography as the gold standard.Results:Total numbers of 58 stents were evaluated, in which stent intraluminal enhancement was assessed in initial, middle, and end sites of stent, achieved cutoff points for more than 50% of ISR were 204, 168, and 204 Hounsfield units, respectively. These cutoff points had diagnostic value of 77.5% for initial part, 86% for midpart, and 81% for end part, respectively.Conclusion:The use of quantitative method of stent intraluminal EV for ISR estimation has better diagnostic value in comparison to qualitative techniques that can help better clinical decision making. Moreover, measurements of this method are somewhat easier and also secondary artifacts of stent struts and calcified plaques would be eliminated.

Computed tomography coronary angiography vs. standard diagnostic procedure for the diagnosis of angina due to coronary heart disease: A cross-sectional study.

Patients with episodes of angina are likely to experience future cardiac events and benefit from a revascularization procedure. Conventional invasive coronary angiography is a well-established and reliable method for the detection of angina, but it has a risk of complications and false-negative diagnosis. The objective of the present study was to assess the utility of computed tomography coronary angiography (CTCA) in the diagnosis of angina due to coronary heart disease. A total of 2,426 patients with chest pain referred to the rapid access chest pain clinic of Beijing Anzhen Hospital, Capital Medical University (Beijing, P.R. China) between 18 January 2016 and 1 December 2017 were included in the present cross-sectional study. All patients were subjected to evaluation of symptoms, blood tests, 12-lead electrocardiogram (ECG), exercise ECG, coronary artery calcium scoring and CTCA. The cost of the diagnosis of angina was determined for each individual method. In total, 776 (32%) and 1,420 (58%) of patients were identified to be abnormal on clinical assessment and CTCA, respectively. Exercise ECG results were not correlated with the interpretation of CTCA (r=0.8511). The working area of the angina due to coronary heart disease detected at one time by the different diagnostic procedures was in the order of ECG <clinical assessment <exercise ECG <coronary artery calcium scoring <CTCA. The cost of the ‘standard diagnostic procedure (clinical assessments, ECG, exercise ECG)’ was 15,452±806 ¥/patient and that of CTCA was 12,546±612 ¥/patient. CTCA had a higher sensitivity for the diagnosis of angina due to coronary heart disease and the cost was lower than that of the ‘standard diagnostic procedure’ (level of evidence: 3). The current study was registered at the Research Registry on 11th January 2016 (trial no. researchregistry4232).

CT Coronary Angiography versus Coronary Angiography to Detect Specificity and Sensitivity of CT Coronary

Background: Various diagnostic tests including conventional invasive coronary angiography and non-invasive Computed Tomography (CT) coronary angiography are used in the diagnosis of Coronary Artery Disease (CAD). Objective: The present report aims to evaluate the specificity and sensitivity of CT coronary angiography in diagnosis of coronary artery disease compared to the standard invasive coronary angiography. Methods: A retrospective study was done over 2 years started from May of 2015 up to May of 2017. The medical evaluation was based on systematic reviews of diagnostic studies with invasive coronary angiography and those with CT coronary angiogram. Data on special indications (bypass grafts, in-stent-restenosis) were also included in the evaluation. The CT scanners used with 320 slices. The study included patients with diabetes, hypertension, and data included age, glomerular filtration rate and ejection fraction. Results: Of the 99 patients included in the study, sensitivity of the total lesions were 87.1% which was highest for the graft lesions (100% sensitivity) and lowest for the Left Main (LM) lesions (83.3% sensitivity), on the other hand the specificity of the total lesion were high (98.1% specificity) which also was highest for the graft lesions (100% specificity) and lowest for the Left Anterior Descending (LAD) lesions (95% specificity). Regarding accuracy, CT coronary was 96.6% accurate for the whole lesions. Conclusions: From a medical point of view, CT coronary angiography using scanners with at least 320 slices should be recommended as a test to rule in obstructive coronary stenosis in order to avoid inappropriate invasive coronary angiography in patients with an intermediate pretest probability of CAD. Multi detector CT (MDCT) has reasonably high accuracy for detecting significant obstructive CAD when assessed at artery level.

Clinical implication of multi-slice computed tomography coronary angiography for symptomatic patients in clinical practice

Aim: Multi-slice computed tomography coronary angiography (MDCTA) has been reported as an effective alternative to invasive conventional coronary angiography (CCA) for the diagnosis of coronary artery disease (CAD). However, in previous reports, the diagnostic accuracy of MSCT has not been significant enough to be of benefit in symptomatic patients. The aim of this study was to identify the usefulness of multi-slice computed tomography coronary angiography for symptomatic patients in terms of the diagnostic accuracy of MDCTA and the prevalence of vasospastic angina pectoris (VSAP) within the study cohort.

Diagnostic accuracy of 64 slice ct coronary angiography for diagnosing significant coronary artery stenosis

Objective: To determine the diagnostic accuracy of 64 slice CT angiography in the detection of significant coronary artery stenosis in patients suspected to have coronary artery disease keeping invasive conventional coronary angiography as gold standard. Methods: The cross-sectional study was conducted at KRL Hospital, Islamabad and data was obtained during the period of six months from April 2014 to October 2014. All the patient of either gender from the age of 35 to 70years who had H/O angina and without any known CAD were included. CCTA and conventional invasive angiography (CIA) findings were recorded in every patient. Occlusion of &gt;50% in coronary artery considered as positive angiography. Results: Among 135 patients 82.2% (n=111) of patients were males and 17.8% n=(24) were females. 63.7% (n=86) of patients were CCTA positive and 65.9% (n=89) of patients had disease on CIA. Sensitivity, specificity, PPV, NPV and accuracy were found to be 91.1%, 89.1%, 94.2%, 83.7% and 90.4% respectively. Conclusion: CCTA with improved spatial resolution and premedication with oral beta-blockade permits detection of coronary artery stenosis with high accuracy. Further large scale studies are needed in our setup to validate this technique in routine clinical practice.

Multidetector Computed Tomography Angiography (MD-CTA) of Coronary Artery Bypass Grafts – Update 2017

Coronary artery bypass grafting (CABG) is still an important therapeutic approach in the treatment especially of advanced coronary artery disease. In this study, we elucidate the current role of multidetector computed tomography angiography (MD-CTA) in imaging patients after CABG surgery. This study is based on recent reports in the literature (2007 - 2016) on imaging of CABG using 64-slice MD-CT scanners and beyond. We included 13 reports that compared ECG-gated MD-CTA with conventional invasive coronary angiography (ICA) as the reference standard for the assessment of graft patency and for the detection of > 50 % stenoses. These studies had to provide absolute values for true-positive, true-negative, false-positive and false-negative results or at least allow calculation of these numbers. In total, 1002 patients with 2521 bypass grafts were the basis for this review. The sensitivity and specificity for the assessment of graft patency or the detection of > 50 % graft stenosis were 97.2 % and 97.5 %, respectively. The negative and positive predictive values were 93.6 % and 99 %, respectively. By using prospective ECG-gating and an increasing pitch factor, the radiation dose exposure declined to 2.4 mSv in the latest reports. ECG-gated MD-CTA provides a fast and reliable, noninvasive method for assessing patients after CABG. The most substantial benefit of the newest CT scanner generations is a remarkable reduction of radiation dose exposure while maintaining a still excellent diagnostic accuracy during recent years. · MD-CTA using 64-slice MDCT scanners and beyond is a reliable, noninvasive method for evaluating CABGs.. · Technical advances such as prospective ECG-gating, iterative reconstruction algorithms and high-pitch scanning lead to a remarkable drop-down in radiation dose exposures as low as 2.4 mSv.. · Despite significant dose reductions, MD-CTA could maintain a high diagnostic accuracy in evaluating CABGs in recent years.. · Jungmann F, Emrich T, Mildenberger P et al. Multidetector Computed Tomography Angiography (MD-CTA) of Coronary Artery Bypass Grafts - Update 2017. Fortschr Röntgenstr 2018; 190: 237 - 249.

Diagnostic Performance of Self-navigated Whole-Heart Contrast-enhanced Coronary 3-T MR Angiography

Purpose To evaluate the diagnostic performance of self-navigated whole-heart coronary 3-T magnetic resonance (MR) angiography by using conventional invasive coronary angiography (ICA) as the reference gold standard. Materials and Methods This study was approved by the local ethics committee. Written informed consent was obtained from each patient before the study. Thirty-nine consecutive patients underwent coronary MR angiography and later underwent ICA. Coronary MR angiography was performed with a 3-T imager with contrast agent enhancement during free breathing with self-navigated affine motion correction reconstruction. Coronary segments with reference diameters larger than 1.5 mm were included in the comparison between coronary MR angiography and ICA. The coronary MR angiography images were evaluated by two experienced readers blinded to the ICA results to identify significant luminal narrowing (>50% diameter reduction in reference ICA). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were performed to detect significant coronary artery stenosis. Results Coronary MR angiography examinations were successfully performed in all 39 patients. A total of 327 coronary segments had reference luminal diameter larger than 1.5 mm. Of these 327 coronary segments, 303 (92.7%) segments had a quality score greater than 1 at coronary MR angiography and were included in the analysis. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 78.2%, 75.0%, 81.8%, 70.6%, and 76.9%, respectively, on a per-patient basis. Conclusion Contrast-enhanced self-navigated coronary 3-T MR angiography is a promising technique for the noninvasive detection of clinically significant coronary stenosis. © RSNA, 2016.

Diagnostic performance of 320-slice computed tomography coronary angiography for symptomatic patients in clinical practice

ObjectiveMulti-slice computed tomography (MSCT) coronary angiography has been reported as an effective alternative to invasive conventional coronary angiography (CCA) for the diagnosis of coronary artery disease (CAD). However, in previous reports, the diagnostic accuracy of MSCT has not been significant enough to be of benefit in symptomatic patients. The aim of this study was to identify the usefulness of 320-slice computed tomography coronary angiography (320-CTA) for symptomatic patients in terms of the diagnostic accuracy of 320-CTA and the prevalence of vasospastic angina pectoris (VSAP) within the study cohort. MethodsWe retrospectively analyzed 513 consecutive symptomatic patients with suspected CAD who had undergone 320-CTA and CCA. We determined the diagnostic accuracy of 320-CTA using CCA as the reference standard. Ergonovine provocation tests were performed on patients without significant coronary artery stenosis on CCA. ResultsOf the total cohort of 513 symptomatic patients, 39% had obstructive CAD. The patient based analysis of the accuracy of 320-CTA showed a sensitivity of 91.0%, a specificity of 71.0%, a positive predictive value of 66.5%, and a negative predictive value of 92.5%. Of the 314 symptomatic patients who did not have significant coronary artery stenosis on CCA, 58 (18%) were diagnosed with VSAP using ergonovine provocation tests. DiscussionThe negative and positive predictive values indicate that 320-CTA cannot replace CCA for symptomatic patients. Indeed, a combination of CCA and ergonovine provocation tests should be taken into consideration for symptomatic patients.

Decreased Diagnostic Accuracy of Multislice Coronary Computed Tomographic Angiography in Women with Atypical Angina Symptoms.

Background:Multislice computed tomography (MSCT) coronary angiography (CAG) is a noninvasive technique with a reported high diagnostic accuracy for coronary artery disease (CAD). Women, more frequently than men, are known to develop atypical angina symptoms. The purpose of this study was to investigate whether the diagnostic accuracy of MSCT in women with atypical presentation differs from that in men.Methods:We enrolled 396 in-hospital patients (141 women and 255 men) with suspected or proven CAD who successively underwent both MSCT and invasive CAG. CAD was defined as any coronary stenosis of ≥50% on conventional invasive CAG, which was used as the reference standard. The patients were divided into typical and atypical groups based on their symptoms of angina pectoris. The diagnostic accuracy of MSCT, including its sensitivity, specificity, negative predictive value, and positive predictive value (PPV), was calculated to determine the usefulness of MSCT in assessing stenoses. The diagnostic performance of MSCT was also assessed by constructing receiver operating characteristic (ROC) curves.Results:The PPV (91% vs. 97%, χ2 = 5.705, P < 0.05) and diagnostic accuracy (87% vs. 93%, χ2 = 5.093, P < 0.05) of MSCT in detecting CAD were lower in women than in men. Atypical presentation was an independent influencing factor on the diagnostic accuracy of MSCT in women (odds ratio = 4.94, 95% confidence intervals: 1.16–20.92, Walds = 4.69, P < 0.05). Compared with those in the atypical group, women with typical angina pectoris had higher PPV (98% vs. 74%, χ2 = 17.283. P < 0.001), diagnostic accuracy (93% vs. 72%, χ2 = 9.571, P < 0.001), and area under the ROC curve (0.91 vs. 0.64, Z = 2.690, P < 0.01) in MSCT diagnosis.Conclusions:Although MSCT is a reliable diagnostic modality for the exclusion of significant coronary artery stenoses in all patients, gender and atypical symptoms might have some influence on its diagnostic accuracy.

Comparison of Quantity of Coronary Atherosclerotic Plaques Detected by Computed Tomography Versus Angiography

Numerous clinical studies using coronary computed tomography angiography (CTA) and conventional invasive coronary angiography (ICA) confirmed the strong relation between atherosclerotic disease burden and risk of adverse events. Few studies have compared coronary CTA and ICA regarding semiquantitative plaque burden measurements, reproducibility, and cardiovascular risk assessment. We enrolled 71 consecutive patients (mean age 62 ± 9years, 37% women) from the Genetic Loci and the Burden of Atherosclerotic Lesions study (NCT01738828), who underwent 256-slice multidetector row coronary CTA and ICA at a single site. On average, 42 ± 32days passed between the 2 examinations. A total of 1,016 coronary segments were imaged by both CTA and ICA according the 18-segment Society of Cardiovascular Computed Tomography classification. We excluded 16 segments treated with coronary stents. Overall, 1,000 segments were evaluated for the presence of stenosis severity (<25%: minimal, 25% to 49%: mild, 50% to 70%: moderate, 70% to 99%: severe, 100%: occlusion). We calculated the segment involvement score (SIS) and segment stenosis score. Patients were classified into 4 groups: extensive obstructive (SIS >4 and ≥50% stenosis), extensive nonobstructive (SIS >4 and <50% stenosis), nonextensive obstructive (SIS ≤4 and ≥50% stenosis), or nonextensive nonobstructive (SIS ≤4 and <50% stenosis). CTA detected coronary artery plaques in 49%, whereas ICA showed coronary plaques in 24% of the analyzed 1,000 segments (p <0.001). CTA detected atherosclerotic plaque in 35% of coronary segments where ICA was negative, whereas ICA detected plaque only in 3% of segments where CTA was negative. CTA-based segment scores were significantly greater, SIS: 6.9 ± 3.0 versus 3.3 ± 2.0, segment stenosis score: 16.4 ± 8.8 versus 9.4 ± 6.8 (p <0.001 for both). In conclusion, coronary CTA detected approximately twice as many coronary segments with plaque compared to ICA, which resulted in 52% of the patients being assigned to a greater risk category.

Diagnostic utility of Gadolinium enhanced Coronary CT Angiography compared to Conventional Invasive Coronary Angiography in detection of obstructive Coronary Artery Disease

Background: The current gold standard for assessment of coronary artery disease, Invasive Coronary Angiography (ICA), has inherent risks of an invasive procedure including that of death. In addition use of Iodinated contrasts in ICA and Coronary CT Angiography is often contraindicated due to its renal toxicity and hypersensitivity reactions. Gadolinium, though primarily an MRI contrast, has been shown to produce vascular luminal enhancement making it an attractive alternative contrast agent for use in angiography.Objectives: To assess the possibility of use of Gd-enhanced 64-slice cardiac CT (CCT) for the diagnosis of obstructive coronary artery disease in comparison to invasive coronary angiography.Methods: A total of 25 patients of CAD underwent Gadolinium Enhanced Coronary CT Angiography followed by Invasive Coronary Angiography. The data was analyzed by comparing coronary segments with ≥ 50% stenosis detected by ICA versus detection of the same by Gd-Enhanced CTA, as well as comparison on Per-Vessel basis.Results: Mean age of patients in our study was 53.52 years (range 41-70 years). The total number of coronary segments evaluated by invasive coronary angiography was 379 of which 57 showed ≥ 50% stenosis. Gd-Enhanced CTA detected 47 of these lesions. In comparison to ICA, on Per-segment basis, Gd- Enhanced CTA showed Sensitivity of 82.46%, Specificity of 97.50%, PPV of 85.45% and NPV of 96.95%. Weighted Kappa value was 1, suggestive of strong agreement between the two modalities, excluding agreement by chance.Conclusions: Our study shows Gadolinium Enhanced Coronary CT Angiography is safer alternative for assessment of CAD in patients who have a contraindication for ICA or Iodinated Contrasts with acceptable sensitivity and specificity. Results depend on BMI and coronary calcification.

Anomalous origin of right coronary artery from mid-left anterior descending artery leading to coronary steal phenomenon and ischemia.

Coronary anomalies are usually diagnosed incidentally during coronary angiography. Anomalous origin of the right coronary artery (RCA) from the left anterior descending (LAD) is a rare clinical entity [1, 2]. Noninvasive anatomic assessment by coronary computed tomography (CT) angiography has evolved to become a highly accurate method in the diagnosis of coronary artery disease (CAD), comparable to conventional invasive coronary angiography [3]. We report a case of anomalous RCA originating from the mid-LAD leading to exertional dyspnea. A 50-year-old woman was admitted to our cardiology outpatient clinic with the complaint of exertional dyspnea and atypical chest pain. The patient was not eligible for the treadmill stress test due to congenital hip dislocation. Therefore, we scheduled myocardial perfusion scintigraphy, and hypoperfusion was detected in the mid and basal segments of the anterior region of the heart (Figure 1). These changes were interpreted as mild ischemia. As further investigation, coronary CT angiography was scheduled for the patient. Coronary CT angiography demonstrated a single coronary artery from the left Valsalva sinus. An anomalous RCA originated from the mid-LAD, after the first diagonal branch, coursing to the right, anterior to the pulmonary artery, then trajecting downward into the right atrioventricular groove (Figures 2–4). Figure 1 Tomographic scans during stress myocardial scintigraphy. Perfusion defects in the mid and basal anterior segments in the short-axis (SAX) and vertical long-axis (VLA) views. The resting SAX and VLA views show the normal perfusion Figure 2 Coronary computed tomography angiography image showing an anomalous RCA originating from the mid-LAD and coursing anterior of the aorta and the pulmonary trunk Figure 4 Anatomical course of the anomalous RCA Figure 3 Overview of coronary vessel course in relation to the great arterial vessels aorta and pulmonary trunk Anomalies of the RCA are observed to a relatively lesser extent. Yamanaka and Hobbs [4] reported anomalous RCA at the rate of 0.26% in a series of 126,595 patients. Turkmen et al. reported the incidence of single coronary artery anomaly as 0.031% in a series of 215,140 patients who underwent routine coronary angiography [5]. Although anomalous coronary artery is considered to be a benign entity, it may cause myocardial ischemia and even sudden cardiac death. Most of these patients are asymptomatic and have normal electrocardiograms at rest. However, ischemia may be precipitated by strenuous, prolonged physical activity. Our patient's symptoms emerged only with exercise. Myocardial ischemia should be excluded before a coronary anomaly is considered as benign. Myocardial perfusion scintigraphy is a useful and widespread method for indicating the presence of ischemia. Also, coronary CT angiography may be beneficial in the diagnosis of CAD and coronary anomalies. Coronary tomputed angiography demonstrated a single coronary artery anomaly in our patient (Figures 2–4). The coronary tree was free of significant intraluminal narrowing, atherosclerosis, unusual angling or any compression sign which may explain ischemia. In our case, exertional dyspnea may be partly secondary to the myocardial ischemia, which could result from the steal phenomenon due to single coronary artery anomaly. To the best of our knowledge, this is the first case that shows myocardial ischemia in the LAD region in single coronary artery anomaly despite absence of any significant narrowing in the coronary arteries.

Viability assessment after conventional coronary angiography using a novel cardiovascular interventional therapeutic CT system: Comparison with gross morphology in a subacute infarct swine model

BackgroundGiven the lack of promptness and inevitable use of additional contrast agents, the myocardial viability imaging procedures have not been used widely for determining the need to performing revascularization. ObjectiveThis study is aimed to evaluate the feasibility of myocardial viability assessment, consecutively with diagnostic invasive coronary angiography (ICA) without use of additional contrast agent, using a novel hybrid system comprising ICA and multislice CT (MSCT). MethodsIn all, 14 Yucatan miniature swine models (female; age, 3 months; weight, 28–30 kg) were subjected to ICA followed by balloon occlusion (90 minutes) and reperfusion of the left anterior descending coronary artery. Two weeks after induction of myocardial infarction, delayed hyperenhancement (DHE) images were obtained, using a novel combined machine comprising ICA and 320-channel MSCT scanner (Aquilion ONE, Toshiba), after 2, 5, 7, 10, 15, and 20 minutes after conventional ICA. The heart was sliced in 10-mm consecutive sections in the short-axis plane and was embedded in a solution of 1% triphenyltetrazolium chloride (TTC). Infarct size was determined as TTC-negative areas as a percentage of total left ventricular area. On MSCT images, infarct size per slice was calculated by dividing the DHE area by the total slice area (%) and compared with histochemical analyses. ResultsSerial MSCT scans revealed a peak CT attenuation of the infarct area (222.5 ± 36.5 Hounsfield units) with a maximum mean difference in CT attenuation between the infarct areas and normal myocardium of at 2 minutes after contrast injection (106.4; P for difference = 0.002). Furthermore, the percentage difference of infarct size by MSCT vs histopathologic specimen was significantly lower at 2 (8.5% ± 1.8%) and 5 minutes (9.5% ± 1.9%) than those after 7 minutes. Direct comparisons of slice-matched DHE area by MSCT demonstrated excellent correlation with TTC-derived infarct size (r = 0.952; P < .001). Bland-Altman plots of the differences between DHE by MSCT and TTC-derived infarct measurements plotted against their means showed good agreement between the 2 methods. ConclusionThe feasibility of myocardial viability assessment by DHE using MSCT after conventional ICA was proven in experimental models, and the optimal viability images were obtained after 2 to 5 minutes after the final intracoronary injection of contrast agent for conventional ICA.

Feasibility of coronary calcium and stent image subtraction using 320-detector row CT angiography

BackgroundThe reader confidence and diagnostic accuracy of coronary CT angiography (CCTA) can be compromised by the presence of calcified plaques and stents causing blooming artifacts. Compared to conventional invasive coronary angiography (ICA), this may cause an overestimation of stenosis severity leading to false-positive results. In a pilot study, we tested the feasibility of a new coronary calcium image subtraction algorithm in relation to reader confidence and diagnostic accuracy. MethodsForty-three patients underwent clinically indicated ICA and CCTA using a 320-detector row CT. Median Agatston score was 510. Two data sets were reconstructed: a conventional CCTA (CCTAconv) and a subtracted CCTA (CCTAsub), where calcifications detected on noncontrast images were subtracted from the CCTA. Reader confidence and concordance with ICA for identification of >50% stenosis were recorded. We defined target segments on CCTAconv as motion-free coronary segments with calcification or stent and low reader confidence. The effect of CCTAsub was assessed. No approval from the ethics committee was required according to Danish law. ResultsA total of 76 target segments were identified. The use of coronary calcium image subtraction improved the reader confidence in 66% of these segments. In target segments, specificity (86% vs 65%; P < .01) and positive predictive value (71% vs 51%, P = .03) were improved using CCTAsub compared to CCTAconv without loss in negative predictive value. ConclusionsOur initial experience with coronary calcium image subtraction suggests that it is feasible and could lead to an improvement in reader confidence and diagnostic accuracy for identification of significant coronary artery disease.

Giant coronary aneurysm caused by Kawasaki disease: consistency between catheter angiography and electrocardiogram gated dual-source computed tomography angiography.

We present the case of a 5-year-old child with coronary complications due to Kawasaki disease; this patient unintentionally underwent both dual-source computed tomography (DSCT) coronary angiography and invasive coronary angiographic examination in 2 months. This case highlights the strong consistency of the results between DSCT coronary angiography and invasive coronary angiography. Compared to conventional invasive coronary angiography, DSCT coronary angiography offered additional advantages such as minimal invasiveness and less radiation exposure.