Risultati per: L'imaging nella urolitiasi

Introduction
Perianal fistulising Crohn’s disease (pfCD) is a distinct and debilitating phenotype seen in around one-third of patients with CD. Clinical trials in pfCD are increasingly using magnetic resonance imaging (MRI) criteria as a primary endpoint, but there is heterogeneity in the radiological definition of a healed perianal fistula that currently limits our ability to perform meaningful meta-analyses of studies. Our aim is to standardise outcomes through the generation of an international consensus definition of a radiologically healed fistula.

Methods and analysis
This international Delphi consensus study employs a two-part strategy.
The first is a systematic review to identify a longlist of variables used to define radiological healing in pfCD. MRI-based indices used to score fistula severity and healing will be assessed for their methodological quality using Consensus-based Standards for the selection of health Measurement Instruments (COSMIN). The systematic review protocol will be conducted using COSMIN methodology and reported using Preferred Reporting Items for Systematic Reviews and Meta-Analyses.
The second part will be an online Delphi consensus, guided by the results of the systematic review. Radiologists, gastroenterologists and colorectal surgeons with expertise in the management of pfCD will be invited to take part in two to three rounds of online surveys. Once an a priori threshold of >80% agreement is reached on individual radiological components used to define ‘healing’ and ‘healed’, a final meeting of key stakeholders will be organised to generate a consensus definition of a healed fistula.

Ethics and dissemination
The study has been deemed exempt from a formal Research Ethics Committee review as no patients will participate directly in the consensus process, given the technical nature of the research question. The study is registered with the local R&D department (Reference RD24/007). Publication of this study will help standardise radiological endpoint measurement in clinical trials of pfCD and improve the synthesis and meta-analysis of comparative studies.

PROSPERO registration number
CRD42024504334.

This meta-analysis investigates the association of various cardiac MRI–derived measurements with adverse clinical outcomes in patients with nonischemic dilated cardiomyopathy for the purpose of risk stratification.

Circulation, Volume 150, Issue Suppl_1, Page A4139198-A4139198, November 12, 2024. Introduction:Cardiovascular radiology reports contain valuable diagnostic information linked to images, but the unstructured text format makes feature extraction difficult on a large scale. Large language models (LLMs) allow for feature extraction where string parsing alone is insufficient, but require careful prompting for accurate results.Hypothesis:We hypothesize that a systematic prompting approach using LLMs can expedite the extraction of features from unstructured text in transesophageal echocardiography (TEE) reports.Methods:The data consisted of 7106 intraoperative TEE reports, 600 of which were manually reviewed to obtain pre- and post-intervention ground truth values for left ventricular ejection fraction (LVEF), right ventricular systolic function (RVSF), and tricuspid regurgitation (TR). Reports are paired with an imaging study consisting of 50-200 clips. For each feature considered, 100 of the 600 labeled reports were used to engineer a prompt in Llama-2 that maximized feature extraction accuracy.Results:We found that using multiple, shorter prompts yielded higher accuracy than did fewer, longer prompts. Additionally, when imposing semantic information onto a numerical scale, prompt engineering in combination with string parsing (Figure 1) gave the best results. When evaluated on the 500 labeled reports withheld for testing, the finalized prompts had accuracies of 94.1%, 94.8%, and 91.3% for LVEF, RVSF, and TR, respectively. Using this strategy, 5000 intraoperative TEE reports were analyzed and used to train and evaluate a regression model for LVEF estimation from TEE clips (Figure 2).Conclusion:We have shown that performing prompt engineering on Llama-2 can be used to extract features from unstructured TEE reports in an accurate manner. As an extension of these methods, automated feature prediction from echocardiograms can be used to create rapid, low-cost, and accessible cardiac assessments.

Circulation, Volume 150, Issue Suppl_1, Page ASa1106-ASa1106, November 12, 2024. Introduction/Background:Computed tomography (CT) imaging is a promising method for diagnosing patients after return of spontaneous circulation (ROSC) from cardiac arrest. CT information could alter management, improving patient outcomes. There are data supporting use after out-of-hospital arrests, but use and impact of CT imaging after in-hospital-cardiac arrest (IHCA) has not been investigated.Research Question/Hypothesis:We hypothesize that CT imaging will identify acute pathology, resulting in a change in management.Goals/Aims:Our aim is to describe the rates of use, findings, and consequences of CT imaging after IHCA.Methods/Approach:We screened for the first IHCA on admission between 1/26 2023, and 1/302024 at 3 hospitals. Patients 18 years of age or older who achieved ROSC were included. Information was collected on demographics, type of imaging performed, imaging findings, and whether the findings acutely changed management. A change in management was defined as a subsequent change in medications, procedures, or consultations that would not have otherwise occurred and was specifically performed to reverse, mitigate, or treat the imaging finding, based on review of chart documentation by critical care fellows and medicine residents. Results are reported as counts and percentages.Results:We screened 638 IHCA at 3 hospitals. Of the 201 patients meeting inclusion criteria, 72 (35.8%) died within 24 hours after ROSC. Of those who survived 24 hours, 58 of 129 (45.0%) received CT imaging in the 48 hours after ROSC, 53 (41.1%) received a head CT, 26 (20.2%) received a chest CT, 19 (14.7%) received an abdomen/pelvis CT, and 4 (3.1%) received a CT that was not head, chest, or abdomen/pelvis. The most common findings were ischemic stroke (15), pulmonary airspace opacities (23), and pleural effusion (15). An acute finding (previously unknown) was identified in 32 of 58 scans (55.2%), and there was an acute change in management because of the acute finding in 21 (65.6%) of those patients. For 8 patients (13.8%), the scan identified an acute finding thought to have contributed to the cardiac arrest. Of the 58 patients who received CT imaging, 2 of them (3.4%) suffered cardiac arrest while receiving the CT scan.Conclusions:CT imaging within 48 hours after IHCA frequently identified acute pathology, resulting in a change in management. Complications were seen, although we do not know if these were a result of the CT imaging, related transportation, or other causes.

Circulation, Volume 150, Issue Suppl_1, Page A4140123-A4140123, November 12, 2024. Background/Introduction:Microvascular obstruction (MVO), due to damage to the coronary microvasculature, is a key determinant of infarct size, heart failure and poor outcomes following acute myocardial infarction, and there is currently no treatment for preventing MVO. Real-timein vivoimaging of MVO in the beating rodent heart is challenging due to the limited spatial and temporal resolution from movement artifacts. Here, we apply, for the first time, fiber-optic confocal laser endomicroscopy (CLM) for real-time imaging of the microvasculature in a beating murine heart with acute ischemia/reperfusion injury (IRI), and then monitoring the development of MVO.Methods:Anin vivomurine acute myocardial IRI model (45 min ligation of left coronary artery (LCA) and 30 min reperfusion) was applied. At 10 min prior to ischaemia, 150 µl Dextran-FITC (150 kDa, 10 mg/ml) was injected retro-orbitally, and then CLM imaging with a flexible miniprobe (ProFlex S-1500 with CellVizio system) was applied to the epicardial surface at multiple sites at 5 min post-injection (baseline), 30 min post-ischemia and 30 min post-reperfusion. A nitric oxide donor(NO) nanoparticle (NONP) was synthesized and IV bolus injected into IRI mice 5min prior to reperfusion to prevent MVO.Results:We confirmed visualization of the macro- and microvasculature at various sites on the epicardial surface of the beating heart. Next, we observed reduced microvasculature blood flow below LCA ligature as evidenced by reduced or even totally absence of FITC within the vessels at 30min post-ischemia. The microvasculature at the non-ischemic myocardium was unaffected. Furthermore, at 30 min post-reperfusion, we visualised patchy areas of reduced FITC signal suggesting MVO, and damaged microvasculature as evidenced by leakage of FITC outside the vessel. Interestingly, NONP treatment preserved the microvascular network and prevented MVO at 30 min post-reperfusion with even greater FITC, suggesting increased microvascular blood flow and penetration into cardiac tissue because of the vasodilatory effect of NO in the ischemic area.Conclusion:With CellVizio CLM system, we have demonstrated the MVO development during IRI, and damage to the microvasculature with leakage of dye from vessels into cardiac interstitium, thereby providing a pre-clinical platform to test novel therapeutic agents for preventing MVO. Importantly, we have shown an effective MVO prevention with NO-donor nanoparticle following IRI in mice.

Circulation, Volume 150, Issue Suppl_1, Page A4142110-A4142110, November 12, 2024. Background:Coronary artery calcium (CAC) scans contain more actionable information than the Agatston CAC score. We have previously shown in the Multi-Ethnic Study of Atherosclerosis (MESA) that AI-enabled left atrial (LA) volumetry in CAC scans (AI-CAC) enabled prediction of atrial fibrillation (AF) as early as one year. Furthermore, we have recently shown adding AI-CAC LA volumetry to CHA2DS2-VASc risk score improved stroke prediction in MESA. In this study we evaluated the performance of AI-CAC LA volumetry versus LA measured by human experts using cardiac magnetic resonance imaging (CMRI) for predicting AF and stroke, and compared them with CHARGE-AF risk score, Agatston score, and NT-proBNP.Methods:We used 15-year outcomes data from 3552 asymptomatic individuals (52.2% women, age 61.7±10.2 years) who underwent both CAC scans and CMRI in the MESA baseline examination. We have applied the AutoChamberTM(HeartLung.AI, Houston, TX) component of AI-CAC to 3552 CAC scans. CMRI LA volume was previously measured by human experts. Data on NT-proBNP, CHARGE-AF risk score and the Agatston score were obtained from MESA. Discrimination was assessed using the time-dependent area under the curve (AUC).Results:Over 15 years follow-up, 562 cases of AF and 140 cases of stroke accrued. The AUC for 15-yearAF predictionby AI-CAC LA volume (0.801) was comparable to CMRI LA volume (0.797) and significantly higher than Agatston CAC Score (0.687) and NT-proBNP (0.704). Similarly, the AUC for 15-yearstrokepredictionfor AI-CAC volumetry (0.761) was comparable to CMRI volumetry (0.751) and significantly higher than NT-proBNP (0.631) and Agatston CAC Score (0.646). AI-CAC LA volume outperformed CHARGE AF over 1-3 years for incident AF (p

Circulation, Volume 150, Issue Suppl_1, Page A4139380-A4139380, November 12, 2024. Background:Imaging of conventional PM’s and ICDs are infrequently performed via MRI. While many studies, including theMagnaSafeTrialhave unequivocally supported MRI safety in patients with such devices, theaddedclinical value has rarely been considered. Accordingly, we performed an observational, IRB-approved, prospective study to determine the ‘Additive Value’beyondsafety for patients with conventional PM/ICD’s undergoing clinical MRI.Wehypothesizethat MRI in PM/ICD patients is critical to an existing diagnosis and often markedly alters diagnosis and subsequent downstream patient management.Methods:An MRI Device exam (GE 1.5T,WI) pioneered by cardiologists ( >90% over 10 yrs; 100% over 20 years) was performed. Subsequently, a series of prospective defining questions using Boolean Logic Construct were answered within 1 week of MRI by both MRI technologist and MRI physicians.Questions:1) Did the primary diagnosis change?2) Did the MRI provide additional information to existing diagnosis?3) Was the pre-MRI (tentative) diagnosis confirmed?4) Did subsequent patient management change?If ‘Yes’ was answered to any of the above questions, it was considered that MRI was of value to pt diagnosis and/or impending therapy.Results:Average MRI: 25±14min for 2,008 consecutive patients of which 1,526 (76%) were neuro/neurosurgery, 141 (7%) were musculoskeletal and 341(17%) were CV cases. Upon review: of the Neuro/neurosurgeryMRIs, 1,376 (89%) provided additional information.The diagnosis changed in 1018 (74%), while medical therapy changed in 977 (71%). In only 124 (9%) did MRI simply confirm original diagnosis. ForCardiacpatients, MRI changed the original diagnosis in 235 (69%). MRI did not contribute in 42 (12%) as it was uninterpretable (ICD artifact), while in 64 pts, the diagnosis did not change. Finally, in 146Orthopedicpts, MRI provided additional information in 143 (98%) and in 130 (89%), changed pt care, and in 4 pts (3%), simply confirmed the diagnosis. Importantly, with careful attention to device reprogramming and scanner sequences, no safety or device issues were encountered in any patient all with tracking for >1 year.Conclusion:Via a dedicated program of MRI in PM/ICD patients adds substantial clinical value to diagnosis and subsequent management justifying ant inherent risk(s). Herein, we propose that yet another impediment to the advancement of CMR-PM/ICD strategies can become routine and often life-changing.

Circulation, Volume 150, Issue Suppl_1, Page A4146428-A4146428, November 12, 2024. Introduction:Plaque erosion (PE) has a distinct pathogenesis, clinical presentation, and prognosis than other acute coronary syndrome (ACS) causes such as plaque rupture (PR). At present the ability to distinguish between PE and PR using in vivo imaging is limited. A critical feature of PE is the enrichment of hyaluronic acid (HA) at the luminal interface, which is poorly present in the other types of plaque. To better resolve mechanisms of ACS in vivo, we designed and investigated a new hyaluronan-targeted near-infrared fluorescence (NIRF) molecular imaging agent and tested the agent in vitro, in mouse PE in vivo, and in resected human carotid specimens. NIRF has emerged as a translational intravascular imaging modality that allows visualization of plaque pathobiology in vivo.Methods:The NIRF agent was generated via microwave-assisted solid phase peptide synthesis and was conjugated to the NIR fluorophore CyAl5 (ex/em 643/661 nm), to yield the hyaluronan-targeted NIRF agent (HAT-CyAl5). In vitro binding of HAT-CyAl5 to HA was assessed by fluorescence reflectance imaging (FRI). HAT-CyAl5 or a scramble control peptide-CyAl5 (scrambled-CyAl5) were intravenously injected in an established electrical injury-based mouse model of carotid artery PE; intravital microscopy (IVM, n=7) was performed in mice injected with HAT-CyAl5 (n=4) or scrambled-CyAl5 (n=3). Next, freshly resected human carotid specimens were incubated with HAT-CyAl5 (n=4) or PBS (n=4). Histological analyses then assessed specific binding of HAT-CyAl5 in murine PE and human atheroma.Results:The blood half-life of HAT-CyAl5 was 5.7 minutes (95% CI, 3.4-9.8min). In vitro HA binding analyses showed a significant higher target-to-background ratio (TBR) in the HAT-CyAl5 group (P < 0.03 vs. Scrambled-CyAl5). In carotid PE undergoing IVM, HAT-CyAl5 double the TBR in vivo (4.7 ±1.36 vs. 2.38 ± 0.17 Scrambled-CyAl5, P< 0.05). In human carotid plaques, HAT-CyAl5 markedly increased plaque NIRF signal (TBRpost-incubation - pre-incubation4.95 ±3.36 vs. 0.00 ± 0.15 PBS, P< 0.03). Histology of human plaques showed that HAT-CyAl5 localized well with HA immunohistochemical expression.Conclusion:HAT-CyAl5 is a new NIRF probe that avidly and specifically binds HA in murine PE in vivo and in human plaques. HAT-CyAl5 coupled with intravascular NIRF imaging has the potential to specifically diagnose PE and provide new insights into the pathogenesis of PE.

Circulation, Volume 150, Issue Suppl_1, Page A4144487-A4144487, November 12, 2024. Introduction:T2* cardiac MRI (CMR) is the standard for detecting hemorrhagic myocardial infarction (MI). However, the conventional T2* CMR (2D breath-held, ECG-gated, multi-gradient-echo T2*) can suffer from limited spatial resolution and multiple motion artifacts. We developed a time-efficient, fully ungated, free breathing, 3D T2* mapping method for detecting and characterizing hemorrhagic MI (hMI).Methods:Our approach, developed using a low-rank tensor framework, was tested in a canine model with reperfused hMI. Animals (n=5) underwent CMR 3 days after reperfusion. Short-axis, conventional 2D and proposed 3D T2*-w images, and the corresponding LGE images were acquired in a 3T CMR system. T2* maps (8 echoes, 1.41-15.44 ms) were constructed using mono-exponential fitting. IMH extent was determined by measuring the weighted sum of the imaging slices with hypointense regions (based on ‘mean-2SD’ criterion) within the LGE positive territories. Image quality was assessed by two CMR experts using a Likert scale (1 – poor; and 5 – excellent).Results:Figure 1 shows representative conventional 2D, proposed 3D T2* images, along with LGE image for reference. T2* image scores were higher with the proposed than the conventional approach: 3.5 ± 0.5 (conventional) vs 3.8 ± 0.3 (proposed), p

Circulation, Volume 150, Issue Suppl_1, Page A4136136-A4136136, November 12, 2024. Background:The optimal clinical management and timing of intervention are less well defined in paradoxical low-flow, low-gradient severe aortic stenosis (PLFLG AS). Left ventricular global longitudinal strain (LV-GLS) has been shown to predict outcomes in high flow severe AS, but there is lack of data in patients with PLFLG AS. Given the exaggerated LV hypertrophy and remodeling pattern in PLFLG AS, LV-GLS may be a mechanistic imaging marker for worse outcomes.Hypothesis:In patients with PLFLG AS, LV-GLS is associated with adverse clinical outcomes by detecting subclinical myocardial fibrosis resulting from myocardial remodeling due to LV pressure overload.Methods:We examined patients with PLFLG AS defined as AVA

Circulation, Volume 150, Issue Suppl_1, Page A4143303-A4143303, November 12, 2024. Introduction:Preeclampsia is a hypertensive disorder of pregnancy associated with cardiovascular disease. Systemic peripartum microvascular alternations have been implicated in pregnancies complicated by preeclampsia. Whether coronary microvascular dysfunction is a potential mediator of preeclampsia-associated cardiovascular risk is unknown. We aimed to determine whether individuals with a history of preeclampsia have coronary microvascular dysfunction measured by cardiac magnetic resonance imaging (CMR) at least 5 years postpartum.Methods:Women with singleton pregnancies complicated by preeclampsia and a comparator group with uncomplicated, normotensive deliveries were identified and prospectively enrolled to undergo regadenoson stress perfusion CMR (1.5T Signa Artist GE HealthCare) at least 5 years postpartum. Using the dual sequence technique, fully quantitative perfusion values were determined using Fermi deconvolution. Myocardial perfusion reserve (MPR) was calculated as the ratio of stress to rest myocardial blood flow (MBF).Results:Twenty-three subjects (41.0 ± 6 years, 12.7 ± 5 years post-partum) were included. Women with a history of preeclampsia (n=11) were compared to a control group of women with prior normotensive pregnancy (n=12) (Figure 1A). Obesity and diabetes were more common with preeclampsia, but there was no significant difference in the presence of hypertension between the groups (Table 1A). There was no difference in stress MBF. However, preeclampsia was associated with higher rest MBF (1.47 ± 0.54 mL/g/min vs. 1.19 ± 0.29 mL/g/min; p=0.07) and MPR (1.96 ± 0.46 vs 2.66 ± 1.0; p=0.02) compared to normotensive pregnancy (Figure 1). Similarly, corrected MPR remained significantly lower with prior preeclampsia versus uncomplicated pregnancy (2.36 ± 1.0 vs 3.36 ± 1.46; p=0.03).Conclusions:In this study, we observed significantly reduced coronary microvascular function following a pregnancy complicated by preeclampsia at least 5 years postpartum. Heightened cardiovascular risk factors may attenuate this association; however, these observations indicate that systemic microvascular dysfunction in preeclampsia also involves the coronary microcirculation. Further research is needed to better understand the timing and association of these microvascular changes concerning preeclampsia and later heart disease.

Circulation, Volume 150, Issue Suppl_1, Page A4138701-A4138701, November 12, 2024. Background:Improved understanding of the high-risk features associated with HFpEF may facilitate risk stratification. Cardiac magnetic resonance (CMR)-based strain and structural data can define detailed myocardial structure, which can be leveraged to define heterogenous HFpEF phenotypes. This study used phenotypic clustering integrating CMR-based strain and structural data to identify a high-risk HFpEF phenotype.Methods:Retrospective analyses of 48 HFpEF participants, who underwent cardiac MRI and invasive cardiopulmonary exercise testing (median time between the two studies=40 days), was performed. We conducted unsupervised and unbiased K-means clustering analyses using CMR-based strain and myocardial structural variables. We associated two identified clusters with mortality using Cox proportional hazards modeling and constructed Kaplan-Meier survival curves. A p-value was considered significant if < 0.05.Results:We identified a low (n=32) and high-risk (n=16) cluster. Patients in the identified clusters had similar ages and comorbidities. The high-risk cluster had more male participants and hemodynamically had a higher exercise mPAP/CO and PAWP/CO slope, which are metrics of pulmonary vascular disease. The high-risk cluster displayed greater LV mass, worse biventricular longitudinal strain, decreased right ventricular ejection fraction, and greater interventricular septal angle (all P

Circulation, Volume 150, Issue Suppl_1, Page A4138112-A4138112, November 12, 2024. Background:Mitral annular calcification (MAC) is a common incidental finding associated with advanced renal dysfunction, hyperlipidemia, hypertension, or abnormal calcium metabolism. Caseous mitral annular calcification (CMAC) is a less common MAC variant involving central liquefaction necrosis, which results in a paste-like substance consisting of calcium, fatty acids, and cholesterol.Case description:A 64-year-old female presented to clinic with chronic shortness of breath and fatigue that started after COVID-19 pneumonia in 2021. As part of the initial evaluation, a transthoracic echocardiogram (TTE) was done, which revealed moderate annular calcification, 3+ mitral valve regurgitation, and a 1.8×1.5 cm echogenic mass on the posterior mitral annulus, concerning for possible fungal vegetation. Further multimodality imaging was pursued. Transesophageal echocardiogram confirmed the presence of a 2.0×1.7 cm cystic mass but demonstrated normal mitral valve function. Cardiac MR further identified a 1.2×0.8×1.5 cm hypointense mass, with surrounding late gadolinium enhancement, suggesting an associated inflammatory/degenerative process. Gated cardiac CT scan showed a mass with ring-like dense peripheral calcification and low central attenuation. Overall, findings from multimodality imaging were most consistent with CMAC. In the present case, the patient was monitored conservatively, as her symptoms of shortness of breath improved, and she did not experience any associated complications.Discussion:The present case demonstrates an incidental finding of an echogenic mass on the posterior mitral annulus, later identified as CMAC. Initial imaging with TTE helps evaluate for CMAC. However, on TTE alone, CMAC is often misdiagnosed with other conditions, including intracardiac tumors, abscesses, vegetations, or thrombi, and more advanced imaging is often recommended. On cardiac MR, CMAC is usually hypointense due to the elevated calcium content and may have surrounding late gadolinium enhancement due to associated inflammation. On gated cardiac CT, CMAC presents with a hyperintense rim due to calcification and a hypointense center consistent with central necrosis. As in this patient, CMAC is usually a benign condition that can be monitored conservatively. Indications for invasive intervention include significant valvular dysfunction, embolization, or conduction abnormalities. Multimodal imaging can aid in appropriate diagnosis to mitigate unnecessary interventions.

Circulation, Volume 150, Issue Suppl_1, Page A4142182-A4142182, November 12, 2024. Introduction:Since pulmonary vein isolation (PVI) is often insufficient for persistent atrial fibrillation (PsAF) treatment, rotor ablation targeting AF drivers/substrates has been conducted as potential effective strategy. Recently, substrate location capable of attracting rotor (LR) has been reported to be associated with local fibrosis features. Meanwhile, epicardial adipose tissue (EAT) has been shown to be linked to developing fibrosis and arrhythmogenic substrates. Currently it is not well understood how EAT is related to the LR, and local fibrosis features. Personalized LGE-MRI-based digital twins (DTs) and cardiac CCT can be employed to investigate this.Hypothesis:EAT detected in CCT is correlated with LRs having specific local fibrosis features.Aim:To investigate the correlation between EAT, LRs, and the corresponding local fibrosis features using the merging of LGE-MRI-based DTs and CCT.Methods:Both LGE-MRI and CCT were acquired in 19 consecutive PsAF patients. Bi-atrial DTs incorporating the fibrosis distribution were created, wherein, following virtual PVI, LRs were identified by rapid pacing from 40 bi-atrial sites near fibrosis. In silico ablation was repeated until non-inducibility of rotors (Fig). EAT segmented from CCT and DT were compared after merging them using the bi-atria and 4 PVs as reference points. The distance from each tissue type in DT to the closest EAT (DCE) was calculated. The correlation between local fibrosis density feature (FD) and the median DCE at LRs was analyzed. For each LR, both volumetric FD (vFD) and endo-epi surface FD (sFD), subtracting epicardial surface FD from the endocardial surface FD to measure the dissociation of Endo-Epi surface FDs, were calculated.Results:Among 17 DTs excluding 2 without qualified CCT images, 15 DTs had 95 extra-PVI LRs in total. The DCE of fibrotic tissues (16%) was significantly shorter than that of normal tissues (84%) (p

Circulation, Volume 150, Issue Suppl_1, Page A4146225-A4146225, November 12, 2024. Introduction:Patients who underwent arterial switch operation (ASO) for d-transposition of the great arteries (TGA) are at increased risk for early myocardial ischemia. Stress perfusion cardiac MR (SPCMR) is used as a non-invasive tool for risk stratification but interpretation is often challenging.Hypothesis:There is significant interobserver variability in SPCMR image interpretation in patients with repaired TGA.Aims:1. Determine incidence and severity of adverse effects of stress agents.2. Evaluate incidence of positive SPCMR.3. Assess agreement amongst reviewers in image interpretation.Methods:Patients with repaired TGA with SPCMR imaging from 2013 to 2024 were reviewed. Three patients with previous coronary intervention and one with severe chest pain after adenosine, unable to complete SPCMR, were excluded. 61 studies were performed in 56 patients. Images were independently reviewed by two investigators blinded to initial interpretation and clinical outcome. Perfusion defects were displayed on a circumferential polar plot using standard LV segmentation.Results:Median (IQR) age was 15 (11-17) years, weight 55 (36-68) kg, and BSA 1.6 (1.2-1.8) m2. Max heart rate was 110 (100-125) and systolic BP 127 (116-138). Eleven (20%) patients had cardiac symptoms, chest pain in 9 (16%), syncope in 1 (2%), pallor and distress in 1 (2%) infant. Adverse effects from SPCMR in 8/52 (15%) adenosine, 2/4 (50%) dobutamine, and 0/6 (0%) regadenoson were minor and resolved on stress completion. Six (10%) studies were initially interpreted as suspicious (n=5) or definitive (n=1) perfusion defect (Figure). No LGE was detected. Original interpretation did not match blinded reviews for 6 cases (Figure). Blinded reviewers agreed on 3 negative cases but interpretation differed in the other 3 cases (Figure).Conclusions:SPCMR is safe and feasible. Significant interobserver variability highlights the challenges in qualitative SPCMR interpretation for TGA. Quantitative perfusion may reduce interobserver variability. Larger multicenter studies would be helpful in further elucidating the risk profile of patient characteristics and coronary artery arrangements to determine whether routine use of SPCMR is warranted for TGA patients.

Circulation, Volume 150, Issue Suppl_1, Page A4139978-A4139978, November 12, 2024. Background:Discrepant transthoracic echocardiography (TTE) parameters are not infrequently observed in patients with significant aortic stenosis (AS), however, there is limited literature regarding their computed tomography (CT) characteristics and prognostic implications.Aims:We compared the multi-modality imaging characteristics and outcomes in patients undergoing transcatheter aortic valve replacement (TAVR) by AS subtype.Methods:Patients with severe AS (defined as aortic valve area