Angiographic Projections Research Articles

Prostatic artery embolization performed in anteroposterior projections versus steep oblique projections: single centre retrospective comparative analysis

BackgroundTo present and evaluate an approach for reduction of utilization of steep oblique angiographic projections during prostatic artery embolization (PAE).MethodsSingle-center, retrospective study of patients who underwent bilateral PAE (from October 2018 to November 2019) and in whom it was possible to embolize PA of at least one pelvic side utilizing anteroposterior projections only (AP-PAE group), with the following techniques: Identification of the origin of PA on anteroposterior angiographic views. Utilization of anatomic landmarks from the planning computed tomographic angiography. Distal advancement of the angiographic catheter or microcatheter in the anterior division of internal iliac artery. Gentle probing with microguidewire at the expected site of origin of the PA. The AP-PAE approach was initially applied to all PAE patients during the study period and when this approach failed, additional steep oblique projections were acquired; patients who underwent bilateral PAE, with both anteroposterior and oblique projections for both pelvic sides, formed the standard PAE (S-PAE) group. The AP-PAE group was compared with S-PAE group in terms of baseline clinical and anatomic features, technical/procedural aspects and outcomes.ResultsForty-six patients (92 pelvic sides) were studied. AP-PAE was feasible in 12/46 patients (26.0%): unilateral AP-PAE in 9/46 patients (19.5%); bilateral AP-PAE in 3/46 patients (6.5%). AP-PAE group had larger prostates (p = 0.047) and larger PAs (p < 0.001). Body mass index (BMI) and other baseline features were comparable between the two groups (mean BMI, AP-PAE group: 27.9 ± 3.6, S-PAE group: 27.0 ± 3.5, p = 0.451). Mean fluoroscopy time and dose area product were lower in AP-PAE group (46.3 vs 57.9 min, p = 0.084 and 22,924.9 vs 35,800.4 μGy.m2, p = 0.018, respectively). Three months post PAE, comparable clinical success rates (11/12 vs 31/34, p = 0.959) and mean International Prostate Symptom Score reduction (60.2% vs 58.1%, p = 0.740) were observed for AP-PAE and for S-PAE group, respectively. No major complications were encountered.ConclusionAP-PAE is associated with significant reduction in radiation exposure and appears to be feasible, safe and effective, but it can be applied in a relatively small percentage of patients.

Relationship between high shear stress and OCT-verified thin-cap fibroatheroma in patients with coronary artery disease.

High-risk coronary plaques have been considered predictive of adverse cardiac events. Both wall shear stress (WSS) in patients with hemodynamically significant lesions and optical coherence tomography (OCT) -verified thin-cap fibroatheroma (TCFA) are associated with plaque rupture, the most common underlying mechanism of acute coronary syndrome. The aim of the study was to test the hypothesis that invasive coronary angiography-based high WSS is associated with the presence of TCFA detected by OCT in obstructive lesions. From a prospective study of patients who underwent OCT examination for angiographically obstructive lesions (Yellow II), we selected patients who had two angiographic projections to create a 3-dimensional reconstruction model to allow assessment of WSS. The patients were divided into 2 groups according to the presence and absence of TCFA. Mean WSS was assessed in the whole lesion and in the proximal, middle and distal segments. Of 70 patients, TCFA was observed in 13 (19%) patients. WSS in the proximal segment (WSSproximal) (10.20 [5.01, 16.93Pa]) and the whole lesion (WSSlesion) (12.37 [6.36, 14.55Pa]) were significantly higher in lesions with TCFA compared to WSSproximal (5.84 [3.74, 8.29Pa], p = 0.02) and WSSlesion (6.95 [4.41, 11.60], p = 0.04) in lesions without TCFA. After multivariate analysis, WSSproximal was independently associated with the presence of TCFA (Odds ratio 1.105; 95%CI 1.007-1.213, p = 0.04). The optimal cutoff value of WSSproximal to predict TCFA was 6.79 Pa (AUC: 0.71; sensitivity: 0.77; specificity: 0.63 p = 0.02). Our results demonstrate that high WSS in the proximal segments of obstructive lesions is an independent predictor of OCT-verified TCFA.

Determination of optimal fluoroscopic angulations for aorto-coronary ostial interventions from coronary computed tomography angiography

BackgroundAn optimal aorto-coronary angiographic projection, characterized by an orthogonal visualization of the proximal coronary artery, is crucial for interventional success. We determined the distribution of optimal C-arm positions and assessed their feasibility by invasive coronary angiography. MethodsOrthogonal aorto-coronary ostial angulations were determined in 310 CT data sets. In 100 patients undergoing subsequent invasive angiography, we assessed if the CT-predicted angulations were achievable by the C-arm system. If the predicted projection was not achievable due to mechanical constraints of the C-arm system, the most close, achievable angulation was determined. Patient characteristics were analyzed regarding the distribution of optimal angulations and its feasibility by the C-arm system. ResultsFor the left ostium, CT revealed a mean angulation of LAO 23 ​± ​21°/cranial 25 ​± ​23° (90% of patients with a LAO/cranial angulation, 3% LAO/caudal, 4% RAO/cranial, 3% RAO/caudal) and were achievable by the C-arm system in 87% of patients. For the right ostium, the mean CT-predicted orthogonal angulation was LAO 36 ​± ​37°/cranial 36 ​± ​51° (84% LAO/cranial, 2% LAO/caudal, 14% RAO/caudal) and achievable by the C-arm system in 45% of patients. For the left ostium, a higher body weight was associated with a steeper LAO/cranial angulation being less feasible by the C-arm system due to mechanical constraints. ConclusionsOrthogonal aorto-left coronary angulations show a relative narrow distribution predominately in LAO/cranial position whereas a wider range of angulations was found for the right coronary ostium. The feasibility of CT-predicted angulations by the C-arm system is more restricted for the right than the left coronary ostium.

Validation of novel 3-dimensional quantitative coronary angiography based software to calculate fractional flow reserve post stenting.

ObjectivesTo validate novel dedicated 3D‐QCA based on the software to calculate post PCI vessel‐FFR (vFFR) in a consecutive series of patients, to assess the diagnostic accuracy, and to assess inter‐observer variability.BackgroundLow post percutaneous coronary intervention (PCI) fractional flow reserve (FFR) predicts future adverse cardiac events. However, FFR assessment requires the insertion of a pressure wire in combination with the use of a hyperemic agent.MethodsFAST POST study is an observational, retrospective, single‐center cohort study. One hundred patients presenting with stable angina or non ST‐elevation myocardial infarction, who underwent post PCI FFR assessment using a dedicated microcatheter were included. Two orthogonal angiographic projections were acquired to create a 3D reconstruction of the coronary artery using the CAAS workstation 8.0. vFFR was subsequently calculated using the aortic root pressure.ResultsMean age was 65±12 years and 70% were male. Mean microcatheter based FFR and vFFR were 0.91±0.07 and 0.91±0.06, respectively. A good linear correlation was found between FFR and vFFR (r = 0.88; p <.001). vFFR had a higher accuracy in the identification of patients with FFR values <0.90, AUC 0.98 (95% CI: 0.96‐1.00) as compared with 3D‐QCA AUC 0.62 (95% CI: 0.94‐0.74). Assessment of vFFR had a low inter‐observer variability (r = 0.95; p <.001).Conclusion3D‐QCA derived post PCI vFFR correlates well with invasively measured microcatheter based FFR and has a high diagnostic accuracy to detect FFR <0.90 with low inter‐observer variability.

Optical Coherence Tomography Angiography Projection Artifact Removal: Impact on Capillary Density and Interaction with Diabetic Retinopathy Severity.

PurposeThe purpose of this study was to assess how projection artifact removal (PAR) alters optical coherence tomography angiography (OCTA) assessment of superficial capillary plexus (SCP) and deep capillary plexus (DCP) in eyes of patients with diabetes.MethodsWe acquired 3 × 3 mm scans with RTVue-XR Avanti (Optovue, Inc., Fremont, CA), which were analyzed with PAR software (PAROCTA) and without (non-PAROCTA). SCP, DCP, and full thickness retina vascular density (VD) and vessel linear density (VLD) were manually calculated using ImageJ (version 1.51). Adjusted flow index (AFI) was manually assessed for full thickness images.ResultsAmong 323 eyes of 194 patients (no diabetic retinopathy [DR]: 28 eyes; mild nonproliferative DR (NPDR): 96 eyes; moderate: 82 eyes; severe: 32 eyes; and proliferative DR [PDR]: 81 eyes), SCP VD and VLD were lower with PAROCTA than with non-PAROCTA only in eyes with moderate (VD: P = 0.017; VLD: P = 0.046), severe (P = 0.016; P = 0.009), and PDR (P < 0.001; P = 0.002). DCP VD and VLD were higher with PAROCTA as compared to non-PAROCTA only in eyes with no DR (VD and VLD: P < 0.001), mild (VD and VLD: P < 0.001), moderate (VD: P = 0.005; and VLD: P < 0.001), and severe (VD: P = 0.009; VLD: P < 0.001). Full thickness PAROCTA and non-PAROCTA VD and VLD differed only in eyes with no DR where PAROCTA estimates were higher (VD: P = 0.009; VLD: P = 0.02). PAROCTA AFI was lower than non-PAROCTA AFI for all DR severity levels (P < 0.001) except no DR.ConclusionsAlthough differential effects of PAROCTA software are expected on SCP versus DCP measurements, these findings also suggest an interaction between PAROCTA and DR severity on assessment of VD. Conclusions from previous studies that have not corrected VD with PAR software should be carefully reviewed with regard to the role of specific vascular layers in DR.Translational RelevancePrevious OCTA studies that have not corrected VD with PAR software should be carefully reviewed with regard to the role of individual vascular layers in differing severity levels of DR.

Validation of a three-dimensional quantitative coronary angiography-based software to calculate fractional flow reserve: the FAST study.

The aim of this study was to validate novel software to calculate vessel fractional flow reserve (vFFR) based on 3D-QCA and to assess inter-observer variability in patients who underwent routine preprocedural FFR assessment for intermediate coronary artery stenosis. In vitro validation was performed in an experimental model. Clinical validation was performed in an observational, retrospective, single-centre cohort study. A total of 100 patients presenting with stable angina or non-ST-segment elevation myocardial infarction and an indication to perform FFR between January 2016 and October 2016 were included. vFFR was calculated based on the aortic root pressure along with two angiographic projections and validated against pressure wire-derived FFR. Mean FFR and vFFR were 0.82±0.08 and 0.84±0.07, respectively. A good linear correlation was found between FFR and vFFR (r=0.89; p<0.001). Assessment of vFFR had a low inter-observer variability (r=0.95; p<0.001). The diagnostic accuracy of vFFR in identifying lesions with an FFR ≤0.80 was higher as compared with 3D-QCA: AUC 0.93 (95% CI: 0.88-0.97) vs 0.66 (95% CI: 0.55-0.77), respectively. The 3D-QCA-derived vFFR has a high linear correlation to invasively measured FFR, a high diagnostic accuracy to detect FFR ≤0.80 and a low inter-observer variability.

Assessment of the Annual Eye Lens Dose for Cardiologists During Interventional Procedures Using Anthropomorphic Phantoms and mEyeDose_X Tool

ObjectivesIn this study, eye lens dose measurements were performed using two anthropomorphic phantoms simulating the cardiologist and patient during interventional procedures. BackgroundInterventional procedures known as areas with high potential risk and the cardiologists can receive relatively high doses to their eyes. MethodsThis study was comprised of both phantom and computer simulations. Thermoluminescent dosimeters (TLDs) and mEyeDose_X tool were used to measure and calculate eye lens doses for the cardiologist. 144 TLDs measurements were performed using cardiac protocol for three angiographic projections: anterior-posterior (AP), left anterior oblique 90° (LAO90) and left anterior oblique 45° with cranial 30° (spider) angulations. All cine and fluoroscopy modes including the projections used in this study performed with and without protection tools. ResultsThe annual equivalent doses with protective tools using mEyeDose_X were found to be 1.831 and 1.424 mSv/year, whereas the values using phantom were found to be 2.204 and 1.802 mSv/year for the lens of lift and right eye respectively. ConclusionThe annual doses reported in this study are almost comparable to other studies performed on interventional cardiology (IC) procedures. The highest dose rate in the lens was 20.21 ± 0.015 mSv/h without protective tools in cine mode for spider projection. Cardiologists may therefore easily exceed the lens dose limit if protective tools are not used.

Stent treatment of ostial branch pulmonary artery stenosis: initial and medium-term outcomes and technical considerations to avoid and minimise stent malposition.

Stenting of ostial pulmonary artery stenosis presents several unique challenges. These include difficulty in defining anatomy and need for precise stent placement in order to avoid missing the ostial stenosis or jailing either the contralateral branch pulmonary artery or the ipsilateral upper lobe branch. A retrospective review of outcomes was conducted in 1.5 or 2-ventricle patients who underwent stent placement for ostial branch pulmonary artery stenosis. Specific catheterisation lab techniques were reviewed. Forty-seven branch pulmonary arteries underwent stent placement for ostial stenosis in 43 patients. The median age and weight were 3.7 (0.3-18.1) years and 14.2 (5.6-70.0) kg, respectively. Three (2-8) angiographic projections were needed to profile the ostial stenosis. Open-cell stents were used in 23 and stents were modified in 5 cases. Following stent implantation, the minimum diameter improved from 3.6 (0.8-10.5) to 8.1 (4.2-16.5) mm (p < 0.001). The gradient improved from 21 (0-66) to 4 (0-27) mmHg (p < 0.001). Stent malposition occurred in eight (17%) of the stents placed. Five migrated distally causing suboptimal ostial coverage necessitating placement of a second stent in four. Three migrated proximally and partially jailed the contralateral pulmonary artery. Intentional jailing of the upper lobe branch occurred in four additional cases. At a follow-up of 2.4 (0.3-4.9) years, 15 stents underwent further dilation and 1 had a second stent placed within the exiting stent. Ostial branch pulmonary artery stenosis may require additional angiography to accurately define the ostial stenosis. Treatment with stents is effective but carries high rates of stent malposition.

Feasibility of coronary angiogram-derived vessel fractional flow reserve in the setting of standard of care percutaneous coronary intervention and its correlation with invasive FFR

BackgroundVessel Fractional Flow Reserve (vFFR), a new angiography-derived method for the functional assessment of coronaries, was recently shown to have good correlation with invasive wire-derived FFR, when vFFR-specific image acquisition requirements were followed. We sought to investigate the feasibility of vFFR analysis and its correlation with FFR in the situation where angiography is completed in routine fashion, without intention for virtual analysis. MethodsUtilizing an anonymized database maintained at our Cardiovascular Imaging Core Laboratory, we included angiographic images from patients that underwent pre- and post-PCI FFR. CAAS Workstation 8.1 software (Pie Medical Imaging) was used for vFFR evaluation. ResultsOut of 624 angiograms (312 pre-PCI and 312 post-PCI), vFFR was successfully analyzed in 219 (35.1%) (115 pre-PCI and 104 post-PCI). Reasons for vFFR analysis failure were: <2 angiographic projections (42.5%), table movement while acquisition (25.7%) and resolution incompatibility (15%). From 115 patients with analyzable pre-PCI vFFR, 74 (64.3%) showed agreement with the respective FFR results in terms of positive (≤0.80) vs negative (>0.80) FFR. Pearson's correlation coefficient between them was 0.449 (p < 0.0001). From 104 lesions with analyzable post-PCI vFFR, 94 had availability of FFR, 74 (78.7%) of which showed agreement between the vFFR and FFR. Pearson's correlation between the values was 0.115 (p = 0.2703). ConclusionvFFR could be analyzed in about one-third of previously completed angiographies and a weak correlation was seen between vFFR and FFR. Our results show the importance of following the pre-specified requirements for vFFR analysis. Further studies are needed to validate the software in different settings.

Point-Cloud Method for Automated 3D Coronary Tree Reconstruction From Multiple Non-Simultaneous Angiographic Projections.

X-ray angiography is the most commonly used imaging modality for the detection of coronary stenoses due to its high spatial and temporal resolution of lumen contour and its utility to guide coronary interventions in real time. However, the high inter- and intra-observer variability in interpreting the geometry of 3D vascular structure based on multiple 2D image projections is a limitation in the accurate determination of lesion severity. This could be addressed by the 3D reconstruction of the coronary arterial (CA) tree. The automated reconstruction of 3D CA tree from 2D projections is challenging due to the existence of several imaging artifacts, such as vessel overlap, foreshortening, and most importantly respiratory and cardiac motion. Along with these artifacts, the acquisition geometry introduces the possibility of generating false vessel segments in the reconstruction. Our approach aims to reduce the motion artifacts in angiographic projections by developing a new method for rigid and non-rigid motion correction. A novel point-cloud based approach is subsequently introduced for reconstruction of 3D vessel centerlines by iteratively minimizing the reconstruction error. The performance of the proposed 3D reconstruction is evaluated using angiographic projections from 45 patients, producing average reprojection errors of 0.092 ±0.055 mm and 0.910 ±0.352 mm for 3D centerlines reconstruction, when co-registered with the parent vessels on projection planes that were/were not used to derive the 3D reconstruction, respectively. A comparison of the reconstructed 3D lumen surface with optical coherence tomography (OCT) measurements has been performed, showing no statistically significant difference in the luminal cross-sections reconstructed with our method, compared to OCT.

Accuracy of 3-dimensional and 2-dimensional quantitative coronary angiography for predicting physiological significance of coronary stenosis: a FAVOR II substudy.

Three-dimensional quantitative coronary angiography (3D-QCA) enables reconstruction of a coronary artery in 3D from two angiographic image projections. This study compared the diagnostic accuracy of 3D-QCA vs. 2-dimensional (2D) QCA in predicting physiologically significant coronary stenosis, using fractional flow reserve (FFR) as the reference standard. All interrogated vessels in the FAVOR II China study and the FAVOR II Europe-Japan study were assessed by 2D-QCA and 3D-QCA according to standard operating procedures in core laboratories. QCA analysts were blinded to the corresponding FFR values. A total of 645 vessels from 576 patients with 3D-QCA, 2D-QCA, and FFR were analyzed. Using the conventional cut-off value of 50% for percent diameter stenosis (DS%), 3D-QCA was more accurate in predicting FFR ≤0.80 than 2D-QCA [accuracy 74.0% (95% CI: 69.9-77.7%) vs. 64.9% (95% CI: 61.3-68.7%), difference: 9.1%, P<0.001]. Sensitivity was higher by 3D-QCA compared with 2D-QCA [69.1% (95% CI: 63.0-75.1%) vs. 47.1% (95% CI: 40.5-53.6%), difference: 22.0%, P<0.001] and specificity was similar [76.5% (95% CI: 72.5-80.6%) vs. 74.4% (95% CI: 70.2-78.6%), difference: 2.1%, P=0.40]. Area under the receiver operating characteristic curve was significantly higher for 3D-QCA than for 2D-QCA [0.81 (95% CI: 0.77-0.84) vs. 0.66 (95% CI: 0.62-0.71), P<0.001]. 3D-QCA demonstrated better diagnostic performance in predicting physiologically significant coronary stenosis compared with 2D-QCA, when FFR was used as the reference standard.

Prognostic Value of QFR Measured Immediately After Successful Stent Implantation: The International Multicenter Prospective HAWKEYE Study

ObjectivesThe aim of this study was to investigate the potential role of post–percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) measurements to predict clinical outcomes in patients with successful PCI. BackgroundThe prognostic value of QFR measured immediately after PCI has not been prospectively investigated. MethodsPatients undergoing complete revascularization with successful PCI and stent implantation were eligible for acquisition of projections for QFR computation. At the end of the procedure, 2 angiographic projections for each vessel treated with PCI were acquired. Computation of QFR was performed offline by an independent core laboratory. The primary outcome was the vessel-oriented composite endpoint, defined as vessel-related cardiovascular death, vessel-related myocardial infarction, and ischemia-driven target vessel revascularization. ResultsSeven hundred fifty-one vessels in 602 patients were analyzed. The median value of post-PCI QFR was 0.97 (interquartile range: 0.92 to 0.99). Lesion location in the left anterior descending coronary artery, baseline SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score, lesion length, and post-PCI diameter stenosis were found to be predictors of lower post-PCI QFR. Altogether, 77 events were detected in 53 treated vessels (7%). Post-PCI QFR was significantly lower in vessels with the vessel-oriented composite endpoint during follow-up, compared with those without it (0.88 [interquartile range: 0.81 to 0.99] vs. 0.97 [interquartile range: 0.93 to 0.99], respectively; p < 0.001). Receiver-operating characteristic curve analysis identified a post-PCI QFR best cutoff of ≤0.89 (area under the curve 0.77; 95% confidence interval: 0.74 to 0.80; p < 0.001). After correction for potential confounding factors, post-PCI QFR ≤0.89 was associated with a 3-fold increase in risk for the vessel-oriented composite endpoint (hazard ratio: 2.91; 95% confidence interval: 1.63 to 5.19; p < 0.001). ConclusionsLower values of QFR after complete and successful revascularization predict subsequent adverse events (Angio-Based Fractional Flow Reserve to Predict Adverse Events After Stent Implantation [HAWKEYE]; NCT02811796)

Designing contrasts for rapid, simultaneous parameter quantification and flow visualization with quantitative transient-state imaging

Magnetic resonance imaging (MRI) has evolved into an outstandingly versatile diagnostic modality, as it has the ability to non-invasively produce detailed information on a tissue’s structure and function. Complementary data is normally obtained in separate measurements, either as contrast-weighted images, which are fast and simple to acquire, or as quantitative parametric maps, which offer an absolute quantification of underlying biophysical effects, such as relaxation times or flow. Here, we demonstrate how to acquire and reconstruct data in a transient-state with a dual purpose: 1 – to generate contrast-weighted images that can be adjusted to emphasise clinically relevant image biomarkers; exemplified with signal modulation according to flow to obtain angiography information, and 2 – to simultaneously infer multiple quantitative parameters with a single, highly accelerated acquisition. This is achieved by introducing three novel elements: a model that accounts for flowing blood, a method for sequence design using smooth flip angle excitation patterns that incorporates both parameter encoding and signal contrast, and the reconstruction of temporally resolved contrast-weighted images. From these images we simultaneously obtain angiography projections and multiple quantitative maps. By doing so, we increase the amount of clinically relevant data without adding measurement time, creating new dimensions for biomarker exploration and adding value to MR examinations for patients and clinicians alike.

Case 270.

History A 54-year-old woman presented with typical chest pain during physical training at the gym. She had a history of hypertension controlled with hydrochlorothiazide, without any other cardiovascular risk factor and with neither personal nor family history of ischemic heart disease. She was postmenopausal and had a long-standing history of migraine headaches without hormonal or drug therapy. The patient had no history of clinically important thoracic trauma or invasive chest interventions. Initial electrocardiography (ECG) showed signs of ongoing anterior ST segment elevation myocardial infarction, and emergent coronary angiography with angioplasty and intravascular US were performed ( Fig 1 ). Maximal level of high-sensitive T troponins was 820 ng/L (normal, <13 ng/L), while echocardiography showed a normal left ventricular ejection fraction, with no apparent regional wall motion abnormalities. General physical examination findings were unremarkable, excluding ligamentous hyperlaxity and joint instability. C-reactive protein, rheumatoid factor, antinuclear antibody, cytoplasmic antineutrophil cytoplasmic antibody, and angiotensin-converting enzyme blood test results were negative. For further evaluation, arterial phase ECG-synchronized CT angiography from the skull base to the pubis symphysis was performed ( Fig 2 ). Figure 1a: Coronary angiography of the left anterior descending (LAD) and left circumflex (LCX) arteries (30° right anterior oblique and 20° caudally angulated projection) and intravascular US of the LCX artery were performed. (a) Initial coronary angiography projection. (b) Coronary angiography projection after LAD stent placement. (c, d) Intravenous US images of the distal (c) and proximal (d) LCX artery obtained after b. Figure 1b: Coronary angiography of the left anterior descending (LAD) and left circumflex (LCX) arteries (30° right anterior oblique and 20° caudally angulated projection) and intravascular US of the LCX artery were performed. (a) Initial coronary angiography projection. (b) Coronary angiography projection after LAD stent placement. (c, d) Intravenous US images of the distal (c) and proximal (d) LCX artery obtained after b. Figure 1c: Coronary angiography of the left anterior descending (LAD) and left circumflex (LCX) arteries (30° right anterior oblique and 20° caudally angulated projection) and intravascular US of the LCX artery were performed. (a) Initial coronary angiography projection. (b) Coronary angiography projection after LAD stent placement. (c, d) Intravenous US images of the distal (c) and proximal (d) LCX artery obtained after b. Figure 1d: Coronary angiography of the left anterior descending (LAD) and left circumflex (LCX) arteries (30° right anterior oblique and 20° caudally angulated projection) and intravascular US of the LCX artery were performed. (a) Initial coronary angiography projection. (b) Coronary angiography projection after LAD stent placement. (c, d) Intravenous US images of the distal (c) and proximal (d) LCX artery obtained after b. Figure 2a: Arterial phase electrocardiography-synchronized CT angiography from the skull base to the pubis symphysis was performed after coronary angiography, subsequent interventional procedures, and intravenous US. (a, b) Axial oblique slab maximum intensity projection image at the level of the left (a) and right (b) renal arteries. (c) Coronal volume-rendering image shows an anterior view of the renal arteries. Figure 2b: Arterial phase electrocardiography-synchronized CT angiography from the skull base to the pubis symphysis was performed after coronary angiography, subsequent interventional procedures, and intravenous US. (a, b) Axial oblique slab maximum intensity projection image at the level of the left (a) and right (b) renal arteries. (c) Coronal volume-rendering image shows an anterior view of the renal arteries. Figure 2c: Arterial phase electrocardiography-synchronized CT angiography from the skull base to the pubis symphysis was performed after coronary angiography, subsequent interventional procedures, and intravenous US. (a, b) Axial oblique slab maximum intensity projection image at the level of the left (a) and right (b) renal arteries. (c) Coronal volume-rendering image shows an anterior view of the renal arteries.

Serum Bilirubin as a Predictor of Coronary Artery Disease Severity in Patients Undergoing Primary Percutaneous Coronary Intervention

Introduction: Coronary artery disease (CAD) is one of the most common causes of death worldwide. In 2010, about 7 out of total 53 million deaths were due to ischemic heart disease. The aim of this study is to evaluate the relationship of serum bilirubin level with the severity and complexity of coronary artery disease (CAD) in the patients undergoing primary percutaneous coronary intervention (PCI). Materials and Methods: 70 patients with STEMI who were undergoing primary PCI were included in the study. All the patients included in the study were subjected to full routine investigations and standard coronary angiographic projections. Total bilirubin level was measured and the patients were divided into two groups. Group 1 was with serum TB ( 1 mg/dl). Severity and complexity of coronary artery lesions will be assessed using Gensini score. Results: After PCI, the two studied groups were compared regarding the number of vessels affected by one and more than one vessel disease. Single vessel disease was frequent in Group 2 (71%) with significant p value (0.003). Cardiac enzymes (troponin I) was more in Group 1 (S. Bil 1), p value significance (0, 0001). Also GENSENI was more in Group 1 (S.TB 1) with mean (80.35 vs 34.71) and significant pvalue (0.0001). There was a highly significant negative correlation between serum bilirubin & GENSENI score (r = -0.762, p value 0.0001). Regarding the incidence of complications, incidence was more in Group 1 (S.TB 1), which means a significant difference between both groups with significant p value (0.0001). There was a significant negative correlation between serum bilirubin & incidence of complications (R = -0.38, pvalue 0.001). Also, there was a significant negative correlation between GENSINI score, complication and bilirubin among both groups (r: -0.762\-0.38) with p value (0.0001\0.001) respectively. Conclusion: In conclusion, our results suggested that the Serum Bilirubin level is inversely correlated with the severity of CAD. Also, the SB level is an independent predictor of cardiovascular events in CAD patients. Understandably, our findings need further verification by large-scale, multicenter clinical trials in the future.

Use of Simulator-Based Teaching to Improve Medical Students' Knowledge and Competencies: Randomized Controlled Trial.

BackgroundSimulator-based teaching for coronary angiography (CA) is an attractive educational tool for medical students to improve their knowledge and skills. Its pedagogical impact has not been fully evaluated yet.ObjectiveThe aim of this study was to compare traditional face-to-face teaching with a simulator-based teaching for the acquisition of coronary anatomy knowledge and CAs interpretation.MethodsA total of 118 medical school students in their fourth to sixth year were prospectively randomized in 2 groups: (1) a control teaching group (n=59, CONT group) and (2) a simulator group (using the Mentice VIST-Lab CA simulator; n=59, SIM group). The CONT group received a PowerPoint-based course, whereas the SIM group received a simulator-based course including the same information. After the course, all students were evaluated by 40 multiple choice questions (maximum of 100 points), including questions on coronary anatomy (part 1), angiographic projections (part 2), and real CAs interpretation (part 3). Satisfaction of the students was also evaluated by a simple questionnaire.ResultsStudent characteristics were identical in both the groups: 62/118 (52.5%) were female and age was 22.6 (SD 1.4) years. Moreover, 35.6% (42/118) were in their fourth year, 35.6% (42/118) were in the fifth year, and 28.8% (34/118) in the sixth year. During the evaluation, SIM students had higher global scores compared with CONT students, irrespective of their year of medical school (59.5 [SD 10.8] points vs 43.7 [SD 11.3] points, P<.001). The same observations were noted for each part of the test (36.9 [SD 6.6] points vs 29.6 [SD 6.9] points, P<.001; 5.9 [SD 3.0] points vs 3.1 [SD 2.8] points, P<.001; and 16.8 [SD 6.9] points vs 10.9 [SD 6.5] points, P<.001; for parts 1, 2, and 3, respectively). Student satisfaction was higher in the SIM group compared with the CONT group (98% vs 75%, P<.001).ConclusionsThis study suggests that simulator-based teaching could potentially improve students’ knowledge of coronary anatomy, angiography projections, and interpretation of real clinical cases, suggesting better clinical skills. These results should encourage further evaluation of simulator-based teaching in other medical specialties and how they can translate into clinical practice.

Quantitative flow ratio derived from diagnostic coronary angiography in assessment of patients with intermediate coronary stenosis: a wire-free fractional flow reserve study.

To evaluate diagnostic accuracy of quantitative flow ratio (QFR). A novel method was used for non-invasive functional assessment of intermediate coronary lesions. Fractional flow reserve (FFR) is the gold standard for functional assessment of intermediate lesions. However, interrogating a stenosis with pressure wire prolongs the procedure, increases costs and carries a risk of procedure-related adverse events. QFR is a wire-free method for computation of FFR based on 3D reconstruction of angiographic images and modified TIMI frame count. We retrospectively computed QFR (Medis Suite XA/QAngio XA 3D/QFR, Medis/Netherlands) in suitable cases with corresponding FFR (PressureWire™, Abbott, US/). Four QFR measures were tested against FFR: (1) fixed-flow QFR (fQFR), (2) vessel QFR (vQFR), (3) lesion QFR (lQFR) and (4) index QFR (iQFR). 857 lesions (740 patients) were reviewed, 306 (268 patients) met technical inclusion criteria for QFR (two optimal angiographic projections > 25° apart; no ostial location, no overlapping/shortening, frame-rate ≥ 15 fps). Mean angiographic percentage diameter stenosis was 51.3 ± 10.18%. Wire-based FFR ≤ 0.80 was found in 130 lesions (42.5%). Strong Pearson correlation was identified for iQFR (r = 0.85), fQFR (r = 0.73), vQFR (r = 0.78) and lQFR (r = 0.70). The optimal QFR decision values corresponding to FFR = 0.80 were iQFR = 0.79 (AUC = 0.94), fQFR = 0.73 (AUC = 0.87), vQFR = 0.77 (AUC = 0.90), and lQFR = 0.83 (AUC = 0.82). Sensitivity and specificity > 95% were identified for iQFR ≤ 0.74 (n = 89, 29%) and > 0.83 (n = 116, 38%), respectively. The QFR value at the pressure transducer position (iQFR) was the best corresponding QFR model. iQFR is characterised by high diagnostic accuracy and used in a hybrid model with FFR which may reduce the number of procedures requiring pressure-wire by two-thirds.

Optimized Computer-Aided Segmentation and Three-Dimensional Reconstruction Using Intracoronary Optical Coherence Tomography.

We present a novel and time-efficient method for intracoronary lumen detection, which produces three-dimensional (3-D) coronary arteries using optical coherence tomographic (OCT) images. OCT images are acquired for multiple patients and longitudinal cross-section (LOCS) images are reconstructed using different acquisition angles. The lumen contours for each LOCS image are extracted and translated to 2-D cross-sectional images. Using two angiographic projections, the centerline of the coronary vessel is reconstructed in 3-D, and the detected 2-D contours are transformed to 3-D and placed perpendicular to the centerline. To validate the proposed method, 613 manual annotations from medical experts were used as gold standard. The 2-D detected contours were compared with the annotated contours, and the 3-D reconstructed models produced using the detected contours were compared to the models produced by the annotated contours. Wall shear stress (WSS), as dominant hemodynamics factor, was calculated using computational fluid dynamics and 844 consecutive 2-mm segments of the 3-D models were extracted and compared with each other. High Pearson's correlation coefficients were obtained for the lumen area (r = 0.98) and local WSS (r = 0.97) measurements, while no significant bias with good limits of agreement was shown in the Bland-Altman analysis. The overlapping and nonoverlapping areas ratio between experts' annotations and presented method was 0.92 and 0.14, respectively. The proposed computer-aided lumen extraction and 3-D vessel reconstruction method is fast, accurate, and likely to assist in a number of research and clinical applications.

Role of Computed Tomography in Planning the Appropriate X-Ray Gantry for Quantitative Aortography of Post-transcatheter Aortic Valve Implantation Regurgitation.

The clinical robustness of contrast-videodensitometric (VD) assessment of aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) has been demonstrated. Correct acquisition of aortic root angiography for VD assessment, however, is hampered by the opacified descending aorta and by individual anatomic peculiarities. The aim of this study was to use preprocedural multi-slice computed tomography (MSCT) to optimize the angiographic projection in order to improve the feasibility of VD assessment.Methods and Results:In 92 consecutive patients, post-TAVI AR (i.e., left ventricular outflow tract [LVOT] AR) was assessed on aortic root angiograms using VD software. The patients were divided into 2 groups: The first group of 54 patients was investigated prior to the introduction of the standardized acquisition protocol; the second group of 38 consecutive patients after implementation of the standardized acquisition protocol, involving MSCT planning of the optimal angiographic projection. Optimal projection planning has dramatically improved the feasibility of VD assessment from 57.4% prior to the standardized acquisition protocol, to 100% after the protocol was implemented. In 69 analyzable aortograms (69/92; 75%), LVOT-AR ranged from 3% to 28% with a median of 12%. Inter-observer agreement was high (mean difference±SD, 1±2%), and the 2 observers' measurements were highly correlated (r=0.94, P<0.0001). Introduction of computed tomography-guided angiographic image acquisition has significantly improved the analyzability of the angiographic VD assessment of post-TAVI AR.

Efficacy of RADPAD protection drape in reducing radiation exposure in the catheterization laboratory—First Indian study

BackgroundOccupational radiation exposureis a growing problem due to increasing number and complexity of interventional procedures.The RADPAD is a lead-free sterile drape containing bismuth and barium that reduces scatter radiation during fluoroscopic procedures. We aimed to study the radiation exposure reduction to operators with the use of RADPAD and also measureradiation doses in different angiographic projections. Methods65 randomly selected patients undergoing elective complex percutaneous coronary intervention (PCI) procedures from January 2017 to 2017 were randomized in a 1:1 pattern with or without the RADPAD. Primary endpoint was the ratio of operator received dose in mrem to total radiation in Gyat the end of the procedure which was designated ‘’Relative operator exposure’’, with or without RADPAD. ResultsDespite similar fluoroscopy times (20.4 ± 9.4 min with RADPAD vs. 19.4 ± 9.2 min without RADPAD, P = 0.871) and total radiation dose (3.4 ± 4.3 Gy with RADPAD vs. 2.3 ± 1.4 Gy, P = 0.198), the relative operator exposure was significantly less with RADPAD (1.39 ± 0.95) as compared to no RADPAD group (2.27 ± 1.4) (p = 0.004) amounting to a 39% reduction. Additionally mean radiation dose per shoot of recorded Left anterior oblique (LAO) oriented projections was 34.4 ± 15.7mGyvs 24.9 ± 12.9 mGy for a non LAO oriented projection. (p < 0.001). ConclusionRADPAD significantly reduces radiation exposure to the primary operator during prolonged complex PCI procedures. Further, amongst all views, LAO views have significantly higher emitted radiation as compared to Non LAO views and need more radiation protection.