Per-segment Analysis Research Articles

Preprocedural imaging with cardiac computed tomography for endo-epicardial ventricular tachycardia ablation

BackgroundStudies evaluating the systematic use of cardiac computed tomography (CCT) for the preprocedural assessment of myocardial fibrosis are limited. Their implementation in the electrophysiology workflow has not been extensively described. ObjectiveThis study aimed to explore the degree of concordance between CCT and electroanatomic mapping (EAM) for the evaluation of cardiac fibrosis in patients undergoing endo-epicardial ventricular tachycardia (VT) ablation. MethodsFrom November 2017 to December 2021, patients undergoing endo-epicardial VT catheter ablation with CCT as the only source of preprocedural scar assessment were prospectively enrolled. After image integration, myocardial fibrosis detected with CCT was compared with low-voltage areas identified by endo-epicardial EAM. Postprocedural VT recurrences of this approach were evaluated after at least 1 year of follow-up. ResultsThe study enrolled 35 patients (mean age, 60.7 ± 13.2 years; 94.2% male). The most common underlying arrhythmic substrate was dilated cardiomyopathy (48.6%). CCT was employed for contraindications to cardiac magnetic resonance, such as unstable VTs (31.4%) or nonconditional implantable cardioverter-defibrillators (28.6%), but also for patients’ and operators’ preferences (14.3%–25.7%). Myocardial fibrosis was correctly identified by CCT and EAM, with strong agreement between these techniques both overall (Cohen κ for agreement, 0.933) and in per-segment analysis (κ ranging from 0.796 to 1.0). Ischemic patients showed the best correlation (κ = 1.000), whereas myocarditis showed the worst (κ = 0.750). After a median follow-up of 14 (12–24) months, 1-year freedom from recurrences was achieved in 74.3% patients; overall freedom from recurrences was 60.0%. ConclusionA CCT-based preprocedural assessment before VT ablation is feasible, showing high diagnostic concordance with EAM in detecting myocardial fibrosis.

CTA Supplemented by CTP Increases Interrater Reliability and Endovascular Treatment Use in Patients with Aneurysmal SAH.

Cerebral vasospasm is a common complication of aneurysmal SAH and remains a risk factor for delayed cerebral ischemia and poor outcome. The interrater reliability of CTA in combination with CTP has not been sufficiently studied. We aimed to investigate the reliability of CTA alone and in combination with CTP in the detection of cerebral vasospasm and the decision to initiate endovascular treatment. This is a retrospective single-center study including patients treated for aneurysmal SAH. Inclusion criteria were a baseline CTA and follow-up imaging including CTP due to suspected vasospasm. Three neuroradiologists were asked to grade 15 intracranial arterial segments in 71 cases using a tripartite scale (no, mild <50%, or severe >50% vasospasm). Raters further evaluated whether endovascular treatment should be indicated. The ratings were performed in 2 stages with a minimum interval of 6 weeks. The first rating included only CTA images, whereas the second rating additionally encompassed CTP images. All raters were blinded to any clinical information of the patients. Interrater reliability for per-segment analysis of vessels was highly variable (κ = 0.16-0.61). We observed a tendency toward higher interrater reliability in proximal vessel segments, except for the ICA. CTP did not improve the reliability for the per-segment analysis. When focusing on senior raters, the addition of CTP images resulted in higher interrater reliability for severe vasospasm (κ = 0.28; 95% CI, 0.10-0.46 versus κ = 0.46; 95% CI, 0.26-0.66) and subsequently higher concordance (κ = 0.23; 95% CI, -0.01-0.46 versus κ = 0.73; 95% CI, 0.55-0.91) for the decision of whether endovascular treatment was indicated. CTA alone offers only low interrater reliability in the graduation of cerebral vasospasm. However, using CTA in combination with CTP might help, especially senior neuroradiologists, to increase the interrater reliability to identify severe vasospasm following aneurysmal SAH and to increase the reliability regarding endovascular treatment decisions.

Validation of a deep learning-based software for automated analysis of T2 mapping in cardiac magnetic resonance imaging.

The reliability and diagnostic performance of deep learning (DL)-based automated T2 measurements on T2 map of 3.0-T cardiac magnetic resonance imaging (MRI) using multi-institutional datasets have not been investigated. We aimed to evaluate the performance of a DL-based software for measuring automated T2 values from 3.0-T cardiac MRI obtained at two centers. Eighty-three subjects were retrospectively enrolled from two centers (42 healthy subjects and 41 patients with myocarditis) to validate a commercial DL-based software that was trained to segment the left ventricular myocardium and measure T2 values on T2 mapping sequences. Manual reference T2 values by two experienced radiologists and those calculated by the DL-based software were obtained. The segmentation performance of the DL-based software and the non-inferiority of automated T2 values were assessed compared with the manual reference standard per segment level. The software's performance in detecting elevated T2 values was assessed by calculating the sensitivity, specificity, and accuracy per segment. The average Dice similarity coefficient for segmentation of myocardium on T2 maps was 0.844. The automated T2 values were non-inferior to the manual reference T2 values on a per-segment analysis (45.35 vs. 44.32 ms). The DL-based software exhibited good performance (sensitivity: 83.6-92.8%; specificity: 82.5-92.0%; accuracy: 82.7-92.2%) in detecting elevated T2 values. The DL-based software for automated T2 map analysis yields non-inferior measurements at the per-segment level and good performance for detecting myocardial segments with elevated T2 values compared with manual analysis.

Association of Smoking, Diabetes, and Dialysis with the Presence of Popliteal Lesions in Femoropopliteal Artery Disease.

Although recent advances in endovascular devices have markedly improved clinical outcomes of femoropopliteal endovascular therapy, lesions located in the popliteal artery are still a major challenge. This study aimed to determine the association of cardiovascular risk factors, including smoking, diabetes mellitus, and dialysis-dependent renal failure, with the location of atherosclerotic lesions in femoropopliteal artery disease. We used a multicenter prospective study database registering patients with symptomatic femoropopliteal artery disease undergoing drug-coated balloon treatment. The analysis included 1912 patients with de novo femoropopliteal lesions. The association of clinical characteristics with popliteal lesions was investigated using the logistic regression model. In addition, the femoropopliteal artery was divided into six segments (the proximal, middle, and distal portions of the superficial femoral artery and P1, P2, and P3 segments of the popliteal artery), and the association of clinical characteristics with the presence of atherosclerotic lesions in the respective arterial segments was investigated. Smoking and dialysis-dependent renal failure showed a statistically significant inverse and positive association with the presence of popliteal lesions, respectively (adjusted odds ratio, 0.66 [95% confidence interval, 0.51-0.85] and 2.01 [1.62-2.49]; P=0.001 and P＜0.001), whereas diabetes mellitus did not (P=0.17). The subsequent per-segment analysis presented similar results. Smoking was inversely associated with popliteal lesions, whereas renal failure on dialysis was positively associated in patients with symptomatic femoropopliteal artery disease who underwent drug-coated balloon treatment. Diabetes mellitus was not significantly associated.

A deep learning approach to predict myocardial fibrosis in early contrast-enhanced CCT images

Abstract Funding Acknowledgements Type of funding sources: None. Background Late gadolinium enhancement (LGE) derived from cardiac magnetic resonance (CMR) has become a method of choice for the evaluation of myocardial tissue composition and detection of myocardial fibrosis. Advances in cardiac computed tomography (CCT) imaging have led to its growing role as possible alternative to CMR, because of its wider availability and suitability for patients with contraindication. Purpose To develop a myocardial fibrosis detection method from early contrast-enhanced CCT (CE-CCT) imaging using a deep learning (DL) approach. Methods Fifty consecutive patients (age: 62±10 y, male 84%) with known left ventricular dysfunction were enrolled. All patients underwent both LGE-CMR and early and delayed CE-CCT. According to the LGE-CMR patterns, patients were classified as ischemic (n=15, 30%) or non-ischemic (n=35, 70%). Scar regions were manually traced on delayed CE-CCT using LGE-CMR as reference. On early CE-CCT images, segments were extracted according to American Heart Association (AHA) 16-segment model and labeled (scar/no scar) based on the delayed CE-CCT manual tracing. A DL model was developed for automatic segmental classification. Results Based on 44187 segments analyzed, 71% of accuracy (ischemic: 66%; non-ischemic: 74%) for detecting scar on early CE-CCT images was achieved (Picture 1). In a per-segment analysis of the 16-segment AHA model, an accuracy of 91% (ischemic: 87%; non-ischemic: 93%) was obtained from early CE-CCT compared to the LGE-CMR. Conclusions DL on early CE-CCT acquisition may allow the detection of myocardial fibrosis without additional contrast-agent administration or radiation exposure, thus reducing the user interaction and visual inspection with benefit in both efforts and time.

Injury patterns of the spine following blunt trauma: A per-segment analysis of spinal structures and their detection rates in CT and MRI

Rationale and objectivesTo provide a detailed analysis of injury patterns of the spine following blunt trauma and establish the role of supplementary MRI by evaluating discrepancies in the detection rates of damaged structures in CT and MRI. Method216 patients with blunt trauma to the spine who underwent CT followed by supplementary MRI were included in this study. Two board-certified radiologists blinded to clinical symptoms and injury mechanisms independently interpreted all acquired CT and MRI images. The interpretation was performed using a dedicated catalogue of typical findings associated with spinal trauma and assessed for spinal stability using the AO classification systems. ResultsLesions to structures associated with spinal instability were present in 31.0% in the cervical spine, 12.3% in the thoracic spine, and 29.9% in the lumbar spine. In all spinal segments, MRI provided additional information regarding potentially unstable injuries. Novel information derived from supplementary MRI changed clinical management in 3.6% of patients with injury to the cervical spine. No change in clinical management resulted from novel information on the thoracolumbar spine. Patients with injuries to the vertebral body, intervertebral disc, or spinous process were significantly more likely to benefit from supplementary MRI. ConclusionIn patients that sustained blunt spinal trauma, supplementary MRI of the cervical spine should routinely be performed to detect injuries that require surgical treatment, whereas CT is the superior imaging modality for the detection of unstable injuries in the thoracolumbar spine.

52 A DEEP-LEARNING APPROACH FOR SCAR DETECTION IN EARLY CONTRAST-ENHANCED CARDIAC COMPUTED TOMOGRAPHY IMAGES

Abstract Diagnosis of myocardial fibrosis has a relevant prognostic and therapeutic role. Scar-tissue analysis is commonly performed with late gadolinium contrast-enhanced (CE) cardiac magnetic resonance (CMR). However, CMR might be contraindicated or unavailable. Coronary computed tomography (CCT), which is the technique of choice for many routine assessments, is emerging as an alternative to CMR. The objective of this study is to evaluate whether artificial intelligence (AI) could allow identification of myocardial fibrosis from routine early CE-CCT images. Fifty consecutive patients with left ventricular dysfunction (LVD), who underwent both CE-CMR and (early and late) CE-CCT were retrospectively selected. According to the late enhancement CMR patterns, patients were classified as with ischemic (n=15, 30%) or non-ischemic (n=25, 70%) LVD. Scar regions were manually traced on late CE-CCT using CE-CMR as ground-truth. On early CE-CCT images, the myocardial sectors were extracted according to AHA 16-segment model and labeled as with scar or not based on the late CE-CCT manual tracing. A deep-learning model was developed to classify each sector (Picture). Of the initial 44187 sectors computed out of the 8285 slices available from the early CE-CCT images, 4594 sectors (10%) presented scar. The CNN approach on the early CE-CCT images yielded a classification accuracy for all sectors of 71% (95% confidence interval (CI): 63%-79%) obtained through 5-fold cross validation. The mean sensitivity, positive predictive value (PPV) and negative predictive value (NPV) for the testing fold resulted in 73% (95% CI: 66%-79%), 56% (95% CI: 48%-65%) and 85% (95% CI: 82%- 88%), respectively. The mean AUC across the five folds was 76% (95% CI: 72%-81%). In a per-segment analysis of the 16-segment AHA model the bull's eye segmental comparison of CE-CMR and respective early CE-CCT findings an 91% agreement was achieved. Artificial intelligence can detect both ischemic and non-ischemic myocardial fibrosis from routine noninvasive coronary scans, without additional contrast-agent administration or radiational dose, thus assisting diagnosis and management of patients with LV dysfunction and coronary artery disease.

Evaluation of acute chest pain – is it possible to associate cardiovascular risk scores (TIMI, HEART, GRACE) and the presence of obstructive plaque on coronary computed tomography angiography?

Abstract Introduction Coronary artery disease (CAD) answers for almost 43.2% of cardiovascular deaths worldwide. In the United States, more than 8 million patients present to the emergency department each year with acute chest pain. Although, as few as 10% will be diagnosed with acute coronary syndrome. Cardiovascular risk scores are frequently used as tools to evaluate the chance of coronary disease, despite the fact that they were initially validated as prognostic schemes to categorize a patient's risk of death and ischemic events. The association of these scores and the presence of obstructive atherosclerotic plaques is scarce. Purpose To associate the presence of obstructive atherosclerotic plaque on coronary computed tomography angiography (CCTA) and cardiovascular risk scores, in the evaluation of patients who present with acute chest pain to the emergency department in a tertiary referral center in cardiovascular disease. Methods This is an observational and retrospective study that evaluated patients presenting to the emergency department with acute chest pain and were referred to CCTA. Exclusion criteria were ischemic EKG signs, positive troponin or history of coronary revascularization. CCTA images were reviewed by trained observers who performed a per-segment analysis to assess coronary artery stenosis, with complex cases classified by consensus. Atherosclerotic plaque was categorized as obstructive if luminal cross-sectional area stenosis was &amp;gt;50% in ≥1 major epicardial artery. Results Overall, 350 patients were recruited (52.6±11.9 years, 50% women) in whom 20.6% (72 patients) had significant atherosclerotic plaque. Male gender (OR: 1.87; 95% CI: 1.08–3.26), age &amp;gt;52 years (OR: 2.85; 95% CI: 1.6–5.07), diabetes (OR: 2.17; 95% CI: 1.12–4.2) and typical angina (OR: 2.17; 95% CI: 1.12–4.2) were the only clinical characteristics independently associated with the presence of obstructive plaque. More then 90% of patients with significant coronary stenosis were classified as low risk by GRACE and TIMI scores. HEART score was &amp;lt;4 in 23.6% of patients with obstructive plaque. Conclusion In patients who present to the emergency department in a tertiary referral hospital with acute chest pain, the initial evaluation based on clinical characteristics and cardiovascular risk scores was not sufficient to exclude safely the presence of coronary artery disease. Therefore, in such patients, CCTA could help to identify those with occult CAD and to target preventative treatments, thereby improving clinical outcomes. Funding Acknowledgement Type of funding sources: None.

A deep-learning approach for scar detection in early contrast-enhanced cardiac computed tomography images

Abstract Background/Introduction Diagnosis of myocardial fibrosis has a relevant prognostic and therapeutic role. Scar-tissue analysis is commonly performed with late gadolinium contrast-enhanced (CE) cardiac magnetic resonance (CMR). However, CMR might be contraindicated or unavailable. Coronary computed tomography (CCT), which is the technique of choice for many routine assessments, is emerging as an alternative to CMR. Purpose The objective of this study is to evaluate whether artificial intelligence (AI) could allow identification of myocardial fibrosis from routine early CE-CCT images. Methods Fifty consecutive patients with left ventricular dysfunction (LVD), who underwent both CE-CMR and (early and late) CE-CCT were retrospectively selected. According to the late enhancement CMR patterns, patients were classified as with ischemic (n=15, 30%) or non-ischemic (n=25, 70%) LVD. Scar regions were manually traced on late CE-CCT using CE-CMR as ground-truth. On early CE-CCT images, the myocardial sectors were extracted according to AHA 16-segment model and labeled as with scar or not based on the late CE-CCT manual tracing. A deep-learning model was developed to classify each sector (Picture 1). Results Of the initial 44187 sectors computed out of the 8285 slices available from the early CE-CCT images, 4594 sectors (10%) presented scar. The CNN approach on the early CE-CCT images yielded a classification accuracy for all sectors of 71% (95% confidence interval (CI): 63%-79%) obtained through 5-fold cross validation. The mean sensitivity, positive predictive value (PPV) and negative predictive value (NPV) for the testing fold resulted in 73% (95% CI: 66%-79%), 56% (95% CI: 48%-65%) and 85% (95% CI: 82%- 88%), respectively. The mean AUC across the five folds was 76% (95% CI: 72%-81%). In a per-segment analysis of the 16-segment AHA model the bull's eye segmental comparison of CE-CMR and respective early CE-CCT findings an 91% agreement was achieved (Picture 2). Conclusions AI can detect both ischemic and non-ischemic myocardial fibrosis from routine noninvasive coronary scans, without additional contrast-agent administration or radiational dose, thus assisting diagnosis and management of patients with LV dysfunction and coronary artery disease. Funding Acknowledgement Type of funding sources: None.

Automated Identification of Coronary Arteries in Assisting Inexperienced Readers: Comparison between Two Commercial Vendors.

Background: to assess the performance and speed of two commercially available advanced cardiac software packages in the automated identification of coronary vessels as an aiding tool for inexperienced readers. Methods: Hundred and sixty patients undergoing coronary CT angiography (CCTA) were prospectively enrolled from February until September 2021 and randomized in two groups, each one composed by 80 patients. Patients in group 1 were scanned on Revolution EVO CT Scanner (GE Healthcare), while patients in group 2 had the CCTA performed on Brilliance iCT (Philips Healthcare); each examination was evaluated on the respective vendor proprietary advanced cardiac software (software 1 and 2, respectively). Two inexperienced readers in cardiac imaging verified the software performance in the automated identification of the three major coronary vessels: (RCA, LCx, and LAD) and in the number of identified coronary segments. Time of analysis was also recorded. Results: software 1 correctly and automatically nominated 202/240 (84.2%) of the three main coronary vessels, while software 2 correctly identified 191/240 (79.6%) (p = 0.191). Software 1 achieved greater performances in recognizing the LCx (81.2% versus 67.5%; p = 0.048), while no differences have been reported in detecting the RCA (p = 0.679), and the LAD (p = 0.618). On a per-segment analysis, software 1 outperformed software 2, automatically detecting 942/1062 (88.7%) coronary segments, while software 2 detected 797/1078 (73.9%) (p < 0.001). Average reconstruction and detection time was of 13.8 s for software 1 and 21.9 s for software 2 (p < 0.001). Conclusions: automated cardiac software packages are a reliable and time-saving tool for inexperienced reader. Software 1 outperforms software 2 and might therefore better assist inexperienced CCTA readers in automated identification of the three main vessels and coronaries segments, with a consistent time saving of the reading session.

CT enterography for evaluation of disease activity in patients with ileocolonic Crohn's disease

BackgroundCT enterography (CTE) is used routinely for assessment of activity and severity in Crohn's disease (CD), but there are few CTE scoring systems. The aim of this study was to develop a quantitative CTE scoring system for ileocolonic Crohn's disease activity.MethodsForty-nine CD patients with ileocolonic involvement were retrospectively included between March 2015 and May 2018. All patients underwent CTE and ileocolonoscopy. Mural hyperenhancement and mural thickening at CTE were scored quantitatively, while mural stratification, submucosal fat deposition, comb sign, perienteric fat hypertrophy and mesenteric fibrofatty proliferation were qualitative variables. A Tobit regression model was applied for assessing the association between Crohn's disease endoscopic index of severity (CDEIS) and CTE variables.ResultsA total of 280 intestinal segments were evaluated. Independent predictors for CDEIS were mural thickness (p < 0.001), mural stratification (p < 0.001) and comb sign (p = 0.002). In order to quantify disease activity based on CTE findings in each segment, a simplified CT enterography index of activity (CTEIA) was derived from logistic regression analysis. The formula was as follows: CTEIA (segment) = 2.1 mural thickness(mm) + 9.7 mural stratification + 5.2 comb sign. There was a high and significant correlation coefficient between CDEIS and CTEIA (r = 0.779, p < 0.001) for per-segment analysis. The model for the detection of ulcerative lesions in the colon and terminal ileum achieved an area under the receiver-operating curve of 0.901 using a cut-off point of 6.25.ConclusionsCTEIA is a new qualitative tool for evaluation of ileocolonic Crohn’s disease, which need to be validated in further studies.

Unenhanced Whole-Heart Coronary MRA: Prospective Intraindividual Comparison of 1.5-T SSFP and 3-T Dixon Water-Fat Separation GRE Methods Using Coronary Angiography as Reference.

BACKGROUND. Coronary MRA is commonly performed at 1.5 T using SSFP acquisitions. Coronary MRA performed at 3 T using SSFP is limited due to impaired fat suppression and has been typically investigated using contrast-enhanced techniques. A Dixon fat-water separation gradient-recalled echo (GRE) method may enable high-quality unenhanced 3-T coronary MRA. OBJECTIVE. The purpose of this study was to compare 1.5-T SSFP and 3-T Dixon water-fat separation GRE methods for unenhanced whole-heart coronary MRA in patients with suspected coronary artery disease (CAD). METHODS. This prospective study included 44 patients (27 men and 17 women; mean age, 59 ± 8 [SD] years) with an intermediate to high risk of CAD who underwent both 1.5-T SSFP and 3-T Dixon GRE coronary MRA examinations before undergoing coronary angiography (CAG). Two radiologists independently assessed coronary arteries in terms of subjective image quality (on a scale of 1-5, with 5 denoting the highest image quality), number of visible segments, apparent contrast-to-noise ratio (CNR; vs myocardium), and presence of significant stenoses. Methods were compared using the mean of the readers' values for apparent CNR and using consensus interpretations for other measures. CAG served as the reference standard for detecting the presence of stenoses. RESULTS. Expressed as a kappa coefficient, interobserver agreement was 0.85 for image quality, 0.85 for segment visibility, and 0.83 for stenosis, and expressed as an intraclass correlation coefficient, interobserver agreement was 0.92 for apparent CNR. The mean overall image quality score was 4.0 ± 1.1 for 3-T Dixon GRE versus 3.0 ± 1.2 for 1.5-T SSFP. The percentage of visible segments for 3-T Dixon GRE versus 1.5-T SSFP was 96.7% versus 88.9% for all segments, 96.9% versus 90.1% for distal segments, and 93.1% versus 77.2% for branch segments. The mean overall apparent CNR was 93.2 ± 29.2 for 3-T Dixon GRE versus 80.8 ± 27.9 for 1.5-T SSFP. The 3-T Dixon GRE method, compared with the 1.5-T SSFP method, showed higher sensitivity and specificity in per-vessel analysis (87.9% vs 77.3% and 83.3% vs 60.6%, respectively), per-segment analysis (84.6% vs 74.8% and 90.9% vs 79.6%, respectively), and per-segment analysis of distal and branch segments (89.7% vs 75.9% and 89.7% vs 73.7%, respectively). CONCLUSION. For unenhanced coronary MRA, 3-T unenhanced Dixon GRE had better image quality and diagnostic performance than 1.5-T SSFP, particularly for distal and branch segments. CLINICAL IMPACT. The 3-T Dixon GRE technique may be preferred to the current clinical standard of the 1.5-T SSFP technique for unenhanced coronary MRA.

Comparison of Triple-Rule-Out Prospectively ECG-triggered Systolic and Diastolic Acquisition Protocol in Patients With Acute Chest Pain.

The purpose of this study was to compare image quality and coronary interpretability of triple-rule-out systolic and diastolic protocols in patients with acute chest pain. From March 2016 to October 2017 the authors prospectively enrolled patients with undifferentiated acute chest pain, who were at low to intermediate cardiovascular risk. Those with heart rate >75 bpm underwent a systolic prospectively triggered acquisition (systolic triggering [ST]), and in those with ≤75 bpm, end-diastolic triggering (DT) was instead performed. Examinations were evaluated for coronary artery disease, aortic dissection, and pulmonary embolism. Image quality was assessed using a Likert scale. Coronary arteries interpretability was evaluated both on a per-vessel and a per segment basis. The occurrence of major adverse cardiovascular events was investigated. The final study population was 189 patients. Fifty-two patients (27.5%) underwent systolic acquisition and 137 (72.5%) underwent diastolic acquisition. No significant differences in overall image quality were observed between DT and ST groups (median score 5 [interquartile ranges 4 to 5] vs. 4 [interquartile ranges 4 to 5], P =0.074). Although both DT and ST protocols showed low percentages of noninterpretable coronary arteries on a per-vessel (1.5% and 6.7%, respectively) and per-segment analysis (1% and 4.7%, respectively), these percentages resulted significantly higher for ST groups ( P <0.001). Obstructive coronary stenosis was observed in 18 patients. Only one case of pulmonary embolism was diagnosed and no cases of aortic dissection were found in our population. No death or major adverse cardiovascular events were observed during follow-up among the 2 groups. Results showed that triple-rule-out computed tomography angiography is a reliable technique in patients with acute chest pain and that an ST acquisition protocol could be considered an alternative acquisition protocol in patients with higher heart rate, reaching a good image quality.

P283 Decrease in bowel wall thickness at intestinal ultrasound accurately detects early endoscopic remission and improvement in ulcerative colitis patients on tofacitinib: a longitudinal prospective cohort study

Abstract Background To assess disease activity in ulcerative colitis (UC) intestinal ultrasound (IUS) highly correlates with endoscopic outcomes. However, data on treatment response evaluated with IUS is limited. In this study we aim to evaluate bowel wall thickness (BWT) at follow-up to determine treatment effectiveness in moderate-severe UC patients treated with tofacitinib according to central read endoscopy and histology. Methods Patients with moderate-severe UC (endoscopic Mayo score (EMS)≥2) starting tofacitinib 10 mg bid were included. Disease activity was evaluated by recorded IUS cine-loops and video-taped endoscopies with biopsies from the sigmoid (SC) and descending colon (DC) at baseline and at 8 weeks. BWT and EMS were assessed per segment (SC and DC). Histology was scored for the SC with the Robarts Histology Index (RHI). BWT, EMS and RHI were centrally read and for IUS there was a second reader. Endoscopic remission (ERem) was defined as EMS=0, endoscopic improvement (EI) as EMS≤1 and endoscopic response (ERes) as a decrease of EMS≥1. For statistical analysis a Wilcoxon signed-rank and Spearman’s test were used. Area under the ROC was used to determine optimal cut-off values. Inter-observer agreement was analyzed by intra-class correlation coefficient (ICC). Results 29 patients were included and started tofacitinib. 10% reached complete ERem after 8 weeks, respectively. Per-segment analysis for EMS showed 22% and 53% reaching ER and 40% and 60% having EI in the SC and DC, respectively. BWT in SC and DC correlated highly with the EMS (rho=0.68, rho=0.75, both p&amp;lt;0.0001) and moderately with RHI (rho=0.49, p=0.002). Patients with EMS≥2 after 8 weeks had an increased BWT (SC: 4.32 ± 1.57 mm, DC: 4.38 ± 1.58 mm) when compared to ERem (SC: 2.10 ± 0.67 mm, DC: mean: 2.00 ± 1.18 mm, both p&amp;lt;0.0001) and EI (SC: 2.29 ± 0.76 mm, DC: 2.56 ± 1.38 mm, both p&amp;lt;0.0001) in the similar segment (Figure 1 and 2). BWT decreased after 8 weeks when there was ERes (SC: mean: -2.59 ± 1.44 mm, DC: -1.82 ± 1.01 mm, both p=0.007) and did not when there was no ERes (Figure 3). BWT cut-off values for ERem are reported in Figure 4. Furthermore, agreement for BWT in the SC and DC was excellent (ICC: 0.92 and ICC: 0.89), respectively. Conclusion BWT reduction showed early endoscopic remission, improvement and response after 8 weeks of tofacitinib treatment and correlated with histology in this central read cohort. Furthermore, accurate and reliable cut-off values for BWT in SC and DC were found for endoscopic remission and improvement. Therefore, IUS should be incorporated in the standard follow-up and close monitoring of UC patients.

Myocardial extracellular volume fraction quantification in an animal model of the doxorubicin-induced myocardial fibrosis: a synthetic hematocrit method using 3T cardiac magnetic resonance.

Visualization of diffuse myocardial fibrosis is challenging and mainly relies on histology. Cardiac magnetic resonance (CMR), which uses extracellular contrast agents, is a rapidly developing technique for measuring the extracellular volume (ECV). The objective of this study was to evaluate the feasibility of the synthetic myocardial ECV fraction based on 3.0 T CMR compared with the conventional ECV fraction. This study was approved by the local animal care and ethics committee. Fifteen beagle models with diffuse myocardial fibrosis, including 12 experimental and three control subjects, were generated by injecting doxorubicin 30 mg/m2 intravenously every three weeks for 24 weeks. Short-axis (SAX) and 4-chamber long-axis (LAX) T1 maps were acquired for both groups. The association between hematocrit (Hct) and native T1blood was derived from 9 non-contrast CMR T1 maps of 3 control beagles using regression analysis. Synthetic ECV was then calculated using the synthetic Hct and compared with conventional ECV at baseline and the 16th and 24th week after doxorubicin administration. The collagen volume fraction (CVF) value was measured on digital biopsy samples. Bland-Altman plots were used to analyze the agreement between conventional and synthetic ECV. Correlation analyses were performed to explore the association among conventional ECV, synthetic ECV, CVF, and left ventricular ejection fraction (LVEF). The regression model synthetic Hct = 816.46*R1blood - 0.01 (R2=0.617; P=0.012) was used to predict the Hct from native T1blood values. The conventional and synthetic ECV fractions of experimental animals at the 16th and 24th week after modeling were significantly higher than those measured at the baseline (31.4%±2.2% and 36.3%±2.1% vs. 22.9%±1.7%; 29.9%±2.4% and 36.1%±2.6% vs. 22.0%±2.4%; all with P<0.05). Bland-Altman plots showed a bias (1.0%) between conventional and synthetic ECV with 95% limits of agreement of -2.5% to 4.4% in the per-subject analysis (n=21) and a bias (1.0%) between conventional and synthetic ECV with 95% limits of agreement of -2.4% to 4.3% in the per-segment analysis (n=294). Conventional and synthetic ECV were well correlated with CVF (r=0.937 and 0.925, all with P<0.001, n=10). Our study showed promising results for using synthetic ECV compared with the conventional ECV for providing accurate quantification of myocardial ECV without the need for blood sampling.

Chronic thromboembolic pulmonary hypertension: evaluation of V/Q SPECT/CT and V/Q Quotient SPECT findings with postoperative results of pulmonary endarterectomy.

We aimed to perform a comparison between V/Q single-photon emission computed tomography/computed tomography (SPECT/CT) and V/Q Quotient single-photon emission computerized tomography (SPECT) in the detection of chronic thromboembolic pulmonary hypertension (CTEPH) and in depicting the extent of the disease on per-segment basis in patients with CTEPH. Between January 2015 and November 2019, a total of 412 patients with pulmonary hypertension secondary to CTEPH at the preoperative assessment underwent pulmonary endarterectomy (PEA), of whom 92 consecutive patients with their V/Q SPECT/CT scans have been performed in our institution prior to PEA were included in this study. Histopathological findings and post-PEA fully resected surgical specimens were used as the reference standard. On a per-patient basis analysis, V/Q SPECT/CT and V/Q Quotient SPECT both revealed CTEPH in the same 85 of the 92 patients (κ = 1) with a detection rate of 92.4%. In six of these patients, chronic thromboembolic disease could not be reported on both of these two methods due to extensive 'matched' V/Q defects. On a per-segment basis analysis, V/Q SPECT/CT and V/Q Quotient SPECT showed a sensitivity of 75.8 and 73.1%, respectively. Correlation analysis results showed a significant correlation (κ = 0.933) between these two methods on a per-segment basis analysis. In the light of histopathological findings and post-PEA surgical specimen examinations, the results of the present study indicated that both V/Q SPECT/CT and V/Q Quotient SPECT showed relatively high efficacy for the detection of CTEPH on per-patient and per-segment bases with an excellent agreement.

Coronary 18F-sodium fluoride PET detects high-risk plaque features on optical coherence tomography and CT-angiography in patients with acute coronary syndrome

Background and aims18F-Sodium Fluoride Positron Emission Tomography (18F–NaF PET) non-invasively detects micro-calcification activity, the earliest stage of atherosclerotic arterial calcification. We studied the association between coronary 18F–NaF uptake and high-risk plaque features on intra-coronary optical coherence tomography (OCT) and CT-angiography (CTCA) and the potential application to patient-level risk stratification. MethodsSixty-two prospectively recruited patients with acute coronary syndrome (ACS) underwent multi-vessel OCT, 18F–NaF PET and CTCA. The maximum tissue to background ratio (TBRmax = standardised uptake value (SUV)max/SUVbloodpool) was measured in each coronary segment on 18F–NaF PET scans. High-risk plaque features on OCT and CTCA were compared in matched coronary segments. The number of patients testing positive (>2SD above the normal range) for micro-calcification activity was determined. ResultsIn 62 patients (age, mean ± standard deviation (SD) = 61 ± 9 years, 85% male) the coronary segments with elevated 18F–NaF uptake had higher lipid arc (LA) (median [25th-75th centile]: 74° [35°–117°] versus 48° [15°–83°], p=0.021), higher prevalence of macrophages [n(%): 37 (62%) versus 89 (39%), p=0.008] and lower plaque free wall (PFW) (50° [7°–110°] versus 94° [34°–180°], p=0.027) on OCT, and a higher total plaque burden (p=0.011) and higher dense calcified plaque burden (p= 0.001) on CTCA, when compared with 18F–NaF negative segments. Patients grouped by increasing number of coronary lesions positive for microcalcification activity (0,1, ≥2) showed decreasing plaque free wall, increasing calcification and increasing macrophages on OCT (respectively p=0.008, p < 0.001 and p=0.028). Conclusions18F–NaF uptake is associated with high-risk plaque features on OCT and CTCA in a per-segment and per-patient analysis in subjects hospitalized for ACS.

Quantification of Calcified Coronary Plaques by Chest Computed Tomography: Correlation with the Calcium Score Technique.

ResumoFundamento A doença cardiovascular representa a principal causa de mortalidade no mundo. Calcificações parietais nas artérias podem ser visualizadas e quantificadas por tomografia computadorizada (TC) em estágios iniciais e subclínicos, sendo expressa em escore de cálcio (EC). Com esse número, é possível estimar o prognóstico de eventos cardiovasculares futuros.Objetivos Correlacionar a detecção e quantificação do EC pela TC do tórax utilizando como padrão-ouro a TC cardíaca sincronizada ao eletrocardiograma.Métodos Estudo transversal e descritivo que selecionou pacientes (n=73) consecutivos para investigação de doença arterial coronariana estável e que realizaram TC cardíaca no período de junho de 2013 a outubro de 2014. Realizado protocolo com TC do tórax e EC, em aparelho de 64 canais. Os valores de p<0,05 foram considerados estatisticamente significativos.Resultados Na avaliação por paciente, após a transformação logarítmica a média do EC sincronizado foi de 8,7 e na TC de tórax foi de 9,4. Prevalência de doença de 49,3% (n= 36). A sensibilidade foi de 97,2% e a especificidade de 100,0%. Observou-se excelente correlação entre os métodos (r= 0,993 com p<0,001). Na avaliação por segmento, a média do EC sincronizado foi de 3,0. Já a média do EC na TC de tórax foi de 3,2. Prevalência de doença de 29,5% (n= 86), com sensibilidade de 95,3% e especificidade de 97,5%. Observou-se também excelente correlação entre os métodos (r= 0,985 com p<0,001).Conclusão O EC sincronizado e não sincronizado têm boa correlação entre si e não mostram resultados estatisticamente diferentes. (Arq Bras Cardiol. 2020; 115(3):493-500)

Role of DECT in coronary artery disease: a comparative study with ICA and SPECT.

Earlier imaging techniques for coronary artery disease (CAD) focused primarily on either morphological or functional assessment of CAD. However, dual-energy computed tomography (DECT) can be used to assess myocardial blood supply both morphologically and functionally. We aimed to evaluate the diagnostic accuracy of DECT in detecting morphological and functional components of CAD, using invasive coronary angiography (ICA) and single photon emission computed tomography (SPECT) as reference standards. Twenty-five patients with known or suspicious CAD and scheduled for ICA were investigated by DECT and SPECT. DECT was performed during the resting state using retrospective electrocardiography (ECG) gating. CT coronary angiography and perfusion images were generated from the same raw data. All patients were evaluated for significant stenosis (≥50%) on both ICA and DECT coronary angiography, and for myocardial perfusion defects on SPECT and DECT perfusion. Comparison was done between ICA and DECT coronary angiography for detection of significant stenosis and between SPECT and DECT perfusion for detecting myocardial perfusion defects. Using ICA as reference standard, sensitivity, specificity, and accuracy of DECT coronary angiography in detecting ≥50% stenosis of coronary artery lumen were 81.6%, 97.8%, and 95.0%, respectively, by segment-based analysis and 92.1%, 96.1%, and 93.7%, respectively, by vessel-based analysis. Using SPECT as the reference standard, the sensitivity, specificity, and accuracy of DECT perfusion in detecting myocardial perfusion defects were 70.4%, 86.4%, and 80.6%, respectively, on per-segment analysis and 90.7%, 66.6%, and 84.7%, respectively, on per-territorial basis. DECT accurately detected coronary artery stenosis and myocardial ischemia using ICA and SPECT as reference standards. In the same scan, DECT can accurately provide integrative imaging of coronary artery morphology and myocardial perfusion.

Combined Coronary CT Angiography and Evaluation of Access Vessels for TAVR Patients in Free-Breathing with Single Contrast Medium Injection Using a 16-cm-Wide Detector CT

To investigate the feasibility of combining coronary computed tomography (CT) angiography (CCTA) and CTA to evaluate access vessels for transcatheter aortic valve replacement (TAVR) patients in free-breathing and with single contrast medium injection using a 16-cm-wide detector CT. One hundred and twenty-one consecutive patients (73.33 ± 6.43 years) referred for TAVR underwent a serious CT scans in free-breathing after one contrast injection: ECG-triggered one-heartbeat axial CCTA, followed by non-ECG-gated neck, thoracic, and abdominal CTA. Patient weight-dependent contrast dose volume at 1.0 mL/kg was used. CT attenuation values of the coronary, neck, aortic, iliac, and femoral arteries were measured and their image quality was evaluated with a 4-point score method. Stenosis (≥50%) in CCTA was evaluated using invasive coronary angiography result as a reference standard. Radiation and contrast doses were assessed. The total dose-length-product for the entire examination was 411.4 ± 91.2 mGy.cm, and the total contrast dose was 57.3 ± 9.9 mL. There were adequate attenuations (>400 HU) in all arteries, and the peripheral access vessels and aortic annulus were evaluable in all patients. In neck CTA, 5 patients had vascular tortuosity, 6 patients had aberrant arteries and there were 212 plaques and 13 severe stenoses among the patients. In CCTA, on the per-segment, per-vessel, and per-patient analysis, CCTA showed a sensitivity and negative predictive value of (95% and 99%), (95% and 99%), and (96% and 98%), respectively, for the entire patient cohort, and (92% and 98%), (92% and 98%), and (88% and 93%), respectively, for patients with atrial fibrillation or heart rate higher than 75 beats. It is feasible to perform a combined CCTA and CTA for evaluating access vessels for TAVR patients in free-breathing with single contrast injection. This approach generates acceptable image quality for all vessels and a high negative predictive value in excluding coronary artery disease with relatively low radiation and contrast doses.