Risultati per: L'imaging nella urolitiasi

Circulation, Volume 148, Issue Suppl_1, Page A15814-A15814, November 6, 2023. IntroductionReperfusion injury after myocardial infarction (MI) can cause additional tissue damage and is associated with adverse outcomes, and inflammation of extra-cardiac tissue may occur post-MI. In this study, we used positron emission tomography (PET) radiotracer [18F]ROStrace to image reactive oxygen species (ROS) in myocardium and in extra-cardiac tissues in a swine model of subacute ischemia-reperfusion injury.MethodsThe mid left anterior descending coronary artery was occluded in three swine for 90 minutes, followed by reperfusion. Baseline and post-MI ROStrace data were acquired 3 days post-MI on the long axial field-of-view PennPET Explorer PET/CT system. A [82]Rb scan was acquired to calculate myocardial blood flow (MBF). Regions of interest (ROIs) were drawn in brain, lungs, bone marrow, spleen, skeletal muscle, myocardium (baseline) and infarcted and non-infarct myocardium (post-MI). ROStrace fractional uptake rate (FUR) was calculated in all ROIs. Cardiac FUR was corrected for MBF. Paired T-tests and Cohen’s d effect size (ES) were used to evaluate the effect of MI on ROStrace activity in cardiac and extra-cardiac tissues. Cardiac MRI was done to quantify infarct size.ResultsIn extra-cardiac tissues, MI had a nonsignificant medium effect on ROS in bone marrow (ES = 0.54, p = 0.45) and spleen (ES = 0.60, p=0.41), and a nonsignificant large effect in skeletal muscle (ES = 1.24, p = 0.17). No effect was seen in brain and lungs. In the heart, MI had a significant large effect on ROS in the region of the infarct, compared to baseline (ES = 3.84, p = 0.02) (Fig. 1). Infarct size on late gadolinium enhanced MRI ranged from 16.73 to 33.62% of the myocardium.ConclusionFor the first time, systemic and local effects on ROS after MI were directly imaged using whole-body [18F]ROStrace PET. We found that ROS are increased in the infarcted myocardium in the subacute phase, and MI leads to moderate-to-large effects in ROS levels in hematopoietic tissues and skeletal muscle.

Circulation, Volume 148, Issue Suppl_1, Page A17749-A17749, November 6, 2023. Introduction:Ablation of non-pulmonary vein triggers (NPVTs) after pulmonary vein isolation (PVI) may reduce atrial fibrillation (AF) recurrence. Localizing a trigger which initiates AF after a single atrial ectopic beat is challenging, especially in the scenario when the trigger P wave is obscured by preceding QRS-T complex.Aim:To evaluate the potential for noninvasive electrocardiographic imaging (ECGi) to localize NPVTs when the P wave morphology is superimposed on the T wave of the previous beat.Methods:We developed an algorithm which overlays and subtracts the preceding QRS-T wave complex from the QRS-T wave complex which is obscuring the P wave of interest, thus revealing the P wave morphology (Figure 1A). Resultant unobscured P waves (from multiple body surface electrodes) are then used for ECGi computation. In five patients undergoing AF ablation, after PVI, we paced from 15 atrial sites where NPVTs commonly arise, and evaluated the epicardial activation maps generated by ECGi both when pacing was timed to ensure an unobscured P wave and when timed to coincide with preceding QRS-T complex. Co-registration of CT-based ECGi activation maps with invasive electroanatomic map (EAM) allowed comparison of the earliest activation site on ECGi map from both the obscured P waves after QRS-T subtraction and unobscured P waves with true pacing locations on EAM (Figure 1B).Results:From 146 pacing sites in our patient cohort, for the unobscured P waves, median distance between earliest site on ECGi map and EAM pacing location was 16 mm (10-21 mm), and for obscured P waves after QRS-T subtraction, median distance was also 16 mm (12-23 mm) (Figure 1C).Conclusion:Using a QRS-T subtraction algorithm, ECGi can approximate origin of paced P waves whether P wave is unobscured or obscured by the preceding QRS-T complex. Spontaneous NPVT P waves are commonly obscured by the QRS-T wave and the ability to rapidly localize an early coupled P wave may facilitate NPVT mapping and ablation.

Circulation, Volume 148, Issue Suppl_1, Page A15154-A15154, November 6, 2023. Introduction:Fluorescence lifetime imaging (FLIm) is an emerging technique that can visualize detailed molecular properties of atherosclerosis. We conducted an in vivo serial molecular characterization of human coronary plaques using a fully-integrated, dual-modal, intravascular optical coherence tomography-FLIm (OCT-FLIm) system to explore the natural history of biochemical plaque composition.Methods:We prospectively enrolled patients with significant coronary artery disease those who underwent 6-month serial OCT-FLIm assessment for non-culprit/non-target lesions. A non-culprit/non-target lesion was defined as medically-treated angiographic mild-to-moderate stenosis diagnosed at index procedure. Biochemical plaque compositions were categorized by FLIm-derived parameters using a dedicated machine learning classifier. Each lesion was quantitatively assessed for the pre-specified plaque compositions and compared with the serial images.Results:Total 53 non-culprit/non-target lesions from 30 patients were enrolled. Angiography- and OCT-defined lesion severity showed no significant difference over the follow-up (p >0.05). Intriguingly, while the macrophage signal intensity decreased after 6 months (p=0.034), FLIm-based quantitative assessment revealed a worsened plaque compositional response by increased loose fibrous tissue (p=0.004) and decreased normal/fibrous tissue burden (p

Circulation, Volume 148, Issue Suppl_1, Page A12853-A12853, November 6, 2023. Introduction:Inflammation and angiogenesis are central to development of atherosclerosis. [64Cu]Cu-DOTATATE and [68Ga]Ga-NODAGA-E[c(RGDyK)]2 (RGD) are PET tracers that can non-invasively visualize somatostatin receptor subtype 2 (SSTR2) and αvβ3integrin expression that represent inflammation and angiogenesis respectively.Hypothesis:Whether an imaging tracer of inflammation can be compared with a tracer of angiogenesis for detection and quantification of the atherosclerotic process in patients from a Phase II cancer trial cohort.Methods:A cohort of patients from Phase II trial were divided in three groups as controls (N=7), at risk (N=6) & diseased (N=7). PET/CT scans with two different tracers were performed in all subjects. The scans were retrospectively analyzed, and tracer uptake (mean of maximum target-to-background ratios (mTBRmax)) were determined in 6 arterial segments. In addition, plaques from patients (N=7) undergoing carotid endarterectomy (CEA) were studied with autoradiography and immunohistochemistry.Results:[64Cu]Cu-DOTATATE uptake in the disease group was significantly higher compared to the control group in the abdominal aorta (4.4 vs 2.1, p=0.02), thoracic aorta (3.0 vs 2.2, p=0.02), aortic arch (2.8 vs 2.2, p=0.03), left carotid artery (2.2 vs 1.3, p=0.02) and the average of all six aortic segments (2.7 vs 2.0, p=0.01) whereas all aortic segments in the disease group showed a higher but a non-significant difference compared to the control group with RGD uptake. A moderate correlation was found between the mean aortic uptake of [64Cu]Cu-DOTATATE & RGD (r=0.41, p=0.01) in patients from the disease group. SSTR2and αvβ3expression was confirmed on ex vivo plaques along with tracer binding.Conclusions:An in vivo imaging marker of inflammation was superior to a marker of angiogenesis in discriminating levels of atherosclerosis. The two markers were weakly correlated in patients with known cardiovascular disease.

Circulation, Volume 148, Issue Suppl_1, Page A14402-A14402, November 6, 2023. Introduction:Gated CTs are used to quantify coronary artery calcium (CAC), a strong predictor of cardiovascular risk across diverse populations. However, inequities in access to gated CTs, typically not covered by insurance, exacerbate health disparities in atherosclerotic cardiovascular disease (ASCVD) risk assessment. Artificial intelligence can quantify CAC on non-gated chest CTs.Objective:We sought to determine sociodemographic differences in utilization of gated CAC scans vs non-gated chest CTs to identify opportunities to improve health equity in ASCVD risk assessment.Methods:We extracted electronic health record data on all gated CAC scans and non-gated chest CTs from 1/1/2021 – 12/31/2022 performed at Stanford Health Care. We excluded all patients with a history of ASCVD based on ICD codes and without any primary care encounters. Statistical analyses were performed using Pearson’s chi-squared test and t-test.Results:Out of 32,369 total CTs in our study, 5,300 (16%) were gated CAC scans and 27,069 (84%) were non-gated chest CTs. Compared with patients who received CAC scans, those who received non-gated CTs were more likely to be older, female, Hispanic, Black, have interpreter needs, and have Medicaid insurance (Table). They had a greater burden of comorbidities and were more likely to have visited the emergency department (16% vs. 5%) and been hospitalized (29% vs. 2%) in the prior year. Patients who underwent non-gated CTs had higher 10-year ASCVD risk scores as compared with those who underwent CAC scans (20% vs. 11%), yet only 24% were on statins.Conclusions:There are significant sociodemographic differences in patients who receive CAC scans vs non-gated chest CTs, highlighting opportunities to improve equity in access to tools for cardiovascular risk assessment through quantification of CAC on non-gated CTs. This supplemental approach can identify more diverse populations with higher ASCVD risk who may benefit from preventive therapies.

Circulation, Volume 148, Issue Suppl_1, Page A16462-A16462, November 6, 2023. Introduction:Polyvascular disease (PolyVD) is a high-risk atherosclerotic phenotype presenting worse cardiovascular outcomes. However, its atherosclerotic features remain to be fully elucidated yet. Near-infrared spectroscopy (NIRS) imaging quantifies lipidic plaque associated with clinical outcome.Hypothesis:Given a clustering of atherogenic risks in PolyVD, PolyVD may exhibit a distinct plaque phenotype, which accounts for their outcome.Methods:224 culprit lesions in 203 CAD patients receiving PCI were evaluated by NIRS imaging. PolyVD was defined as those with additional ASCVD (stroke and/or LEAD). NIRS-derived lipidic plaque feature (maxLCBI4mm) and clinical outcome (all-cause death+non-fatal MI+stroke) were compared in PolyVD and non-PolyVD subjects.Results:28.6% of study subjects exhibited PolyVD. They were older (77 v. 71 years, p=0.02) with a greater frequency of CKD (61 v. 45%, p=0.03). Under the use of statin (81 v. 71%, p=0.15) and ezetimibe (32 v. 21%, p=0.09), PolyVD patients had a lower LDL-C level (73 v. 84 mg/dL, p=0.01). Despite their LDL-C control, maxLCBI4mmdid not differ in two groups (median: 458 v. 576, p=0.19). Moreover, 64% of PolyVD patients still showed maxLCBI4mm≧400 (69% in non-PolyVD, p=0.44). On multivariate analysis, ACS independently predicted maxLCBI4mm≧400 (Figure) in PolyVD patients. Of note, PolyVD presenting ACS had a higher maxLCBI4mm(790 v. 411, p=0.001) compared to those without ACS, whereas this relationship did not exist in non-PolyVD (622 v. 561, p=0.19, Figure). During the 3-year observational period, PolyVD was associated with an elevated risk of MACE (p=0.002).Conclusions:Despite lowering LDL-C levels, PolyVD harbored a large amount of lipidic materials, accompanied by worse cardiovascular outcomes. Given the relationship of ACS with maxLCBI4mmin PolyVD, additional therapies which modulates ACS-related inflammatory activity may be warranted to alter their disease substrate and outcomes.

Circulation, Volume 148, Issue Suppl_1, Page A16140-A16140, November 6, 2023. Introduction:Cardiovascular magnetic resonance (CMR) imaging is recommended for surveillance and risk stratification in patients with hypertrophic cardiomyopathy (HCM), but the role of CMR findings in clinical decision making has not been described in a pediatric population.Methods:In this single center retrospective study we identified all patients with HCM who underwent CMR. We then determined if there was a clinical management change based on CMR findings.Results:We identified 136 patients with an HCM diagnosis from 2005-2022. Of these, 55 patients (40%) underwent 76 CMR studies. The HCM etiology was genetic or familial in 31 (56%), idiopathic in 21 (38%), and syndromic in 3 (5%); 34% of patients were female; and the median age (and IQR) of included patients at first CMR was 12 (9-15) years old. Ten patients underwent more than one CMR. Both awake and sedated CMRs were included and there were no complications. Management changes included confirmation of HCM diagnosis in 9 patients (16%), change in medical therapy for 3 (5%), myectomy recommendation in 1 (2%), and implantable cardioverter defibrillator (ICD) placement recommendation in 11 (20%). Of those recommended for ICD placement, 8 were a result of new late gadolinium enhancement and 3 had massive septal hypertrophy (median Z-score 30) discovered or confirmed by CMR. To date, no ICDs have discharged any shocks. Altogether, changes in clinical management were made based on CMR findings for 22 patients (40%), representing a change in management as a result of 29% of the total CMRs performed.Conclusion:CMR is an important contributor to clinical decision making in the management of children and adolescents with HCM. Specifically, CMR in this population was especially useful in defining the diagnosis of HCM in the presence of an equivocal echocardiogram and deciding to place an ICD. Fewer CMRs contributed to decision making regarding medical therapy and septal myectomy.

Circulation, Volume 148, Issue Suppl_1, Page A18159-A18159, November 6, 2023. Introduction:Tissue characterization using cardiac magnetic resonance (CMR) is helpful for risk stratification in non-ischemic dilated cardiomyopathy (NIDCM).Hypothesis:This study aimed to investigate the predictive role of tissue characterization identified by CMR on cardiac resynchronization therapy (CRT) response.Methods:We retrospectively reviewed the patients who underwent CMR within 1 year before CRT implantation in NIDCM patients at a single tertiary center from January 2018 to September 2022. Late gadolinium enhancement (LGE), native T1, T2 and extracellular volume (ECV) were analyzed. CRT response was defined as a decrease in left ventricular end-systolic volume (LVESV) > 15% or an increase in left ventricular ejection fraction > 5% on TTE after at least 3 months after CRT implantation.Results:Among a total of 101 patients (mean age 66 years, 52.5% of male), 76 (75.2%) patients were defined as CRT responders. CRT responders had more LBBB (96.1% vs. 60.0%, p

Circulation, Volume 148, Issue Suppl_1, Page A11536-A11536, November 6, 2023. Introduction:Rilonacept treatment in RHAPSODY resolved active pericarditis recurrences, and long-term treatment led to sustained risk reduction. Prior analysis linked greater baseline Late Gadolinium Enhancement (LGE), with more rapid recurrence upon rilonacept suspension after 12 weeks of treatment. Serial cardiac magnetic resonance (CMR) imaging (T2-STIR, LGE) enabled longitudinal assessment for tracking clinical improvement, guiding decision-making, and predicting patient outcomes after treatment cessation.Methods:At the long-term extension (LTE) 18-month decision milestone (18MDM), investigators chose, based on clinical status, to continue rilonacept, suspend rilonacept/observe, or discontinue the LTE. An imaging core lab blinded to clinical data measured pericardial thickness and graded pericardial edema (T2-STIR) and LGE at baseline and 18MDM. Pericarditis recurrence was assessed clinically following rilonacept suspension.Results:Baseline and 18MDM CMRs were available for 13 patients. Reductions in pericardial thickness, T2-STIR, and LGE from baseline to 18MDM while on treatment are provided inFigure. CMRs were obtained in 7/8 patients suspending rilonacept at 18MDM: LGE was none/trace, and T2-STIR was negative; yet, 5/7 (71%) had pericarditis recurrence within 1-4 months of rilonacept suspension despite prophylactic colchicine (n=2).Conclusions:Continued clinical improvement during prolonged rilonacept treatment corresponded with improvement on CMR, including reduced pericardial thickness, resolution of pericardial edema on T2-STIR, and resolution of LGE. Negative/trace LGE at 18MDM while on treatment did not predict absence of pericarditis recurrence upon subsequent rilonacept suspension in this size-limited subgroup. Larger prospective studies examining CMR parameters in guiding RP treatment duration decisions and informing associated clinical outcomes are warranted.

Circulation, Volume 148, Issue Suppl_1, Page A17441-A17441, November 6, 2023. Background:Similarities in peripheral vascular anatomy between swine and humans make this animal an ideal model for evaluating the effects of lower extremity angioplasty procedures commonly performed to improve limb blood flow in peripheral artery disease (PAD).Hypothesis:We hypothesized that PET/CT imaging would provide a non-invasive strategy for quantifying the inflammatory response to balloon overdilation injury in a swine model of peripheral angioplasty.Methods:Five Yorkshire pigs (weight = 25 kg) underwent overdilation of the right femoral artery. A balloon catheter (7 mm x 40 mm) was introduced via the carotid artery and guided to the femoral artery under fluoroscopy. The balloon was then inflated to a pressure 1.5 times greater the recommended nominal pressure to induce arterial injury.18F-fluorodeoxyglucose (FDG) PET/CT imaging was performed 14 days after angioplasty to quantifyin vivoinflammation in the injured and control femoral arteries, which was expressed as the maximum standardized uptake value (SUVmax). Pigs were euthanized 14 days post-angioplasty and arteries were harvested and sectioned for gamma counting (18F-FDG uptake), and stained with hematoxylin and eosin histology (H&E), Masson’s trichrome, and alpha-smooth muscle actin (α-SMA) for evaluation of intimal remodeling and smooth muscle cell proliferation.Results:18F-FDG PET/CT imaging quantified a significant increase in inflammation for the injured versus control femoral artery 14 days post-angioplasty (p=0.04). Gamma counting confirmed a significant increase in18F-FDG uptake in the injured artery (p=0.02). H&E revealed a significant increase in intimal thickening in the injured artery (p=0.03). α-SMA expression was also significantly increased in the injured versus control femoral artery (p=0.01), demonstrating an increase in smooth muscle cell proliferation.Conclusions:18F-FDG PET/CT quantifies arterial inflammation resulting from overdilation injury that is associated with intimal remodeling and smooth muscle cell proliferation. PET/CT imaging may provide a non-invasive strategy forin vivotesting of the efficacy of emerging drug-coated endovascular peripheral devices.

Circulation, Volume 148, Issue Suppl_1, Page A13286-A13286, November 6, 2023. Background:Cardiac sarcoidosis (CS) diagnostic guidelines updated in 2006 and in 2017 now include imaging findings of left ventricular (LV) dysfunction (LV EF < 50%) on cardiac MRI and echocardiography as major diagnostic criterion. Limited data is available with regards to co-morbidities clustering in sarcoidosis and CS according to the 2017 updated guideline diagnostic criteria.Methods:A case control, single tertiary medical center study included 558 sarcoidosis patients with documented extracardiac sarcoidosis and completed electrocardiogram and/or cardiac MRI imaging. CS 2006 and 2017 diagnostic criteria and co-morbidity data were extracted from electronic charts and were available for comparison in 540 patients.Results:The total study population was composed of 52.7% (281/540) females, aged 58.9+/-12.6 years old, with diabetes mellitus (DM) present in 29.6% (160/540), HTN in 51.7% (279/540), CAD in 13.3% (72/540), moderate to severe aortic, mitral, or tricuspid valvular disease in 14.8% (80/540), ESRD in 2.4% (13/540), and COPD or asthma in 21.9% (118/540). There was a significant clustering of co-morbidities according to the imaging CS diagnostic criteria. Patients meeting the 2017 CS imaging criteria were found to be older (61.4+/-11.3 vs 58.8+/-12.8 years old in patients not meeting criteria, p=0.085), predominantly male (69.2%, (54/78) vs. 44.4%, (205/462), p

Circulation, Volume 148, Issue Suppl_1, Page A16985-A16985, November 6, 2023. Background:Non-invasive identification of the site of origin (SOO) of ventricular arrhythmias is vital in informing ablation strategy. ECGi is an established method to generate 3D activation maps with a multielectrode vest combined with cardiac CT. EWI is an emerging echocardiography based modality that provides a low cost & non-ionizing mapping alternative.Hypothesis:EWI more precisely localises SOO of Complex Ventricular Ectopy (VEs) & intramural location than commercial ECGi.Aim:Compare spatial accuracy of EWI and ECGi to estimate SOO and validate against contact mapping.Methods:VE-ablation patients underwent preprocedural EWI & ECGi to estimate SOO on the AHA segment-model. A commercial ECGi system with cardiac CT was used for reconstruction of epicardial VE activation maps. EWI was performed using a research ultrasound acquiring B-mode and high frame rate (2000fps) images with simultaneous ECG. Local electromechanical activation was defined as time-point of the downward zero-crossing on the incremental axial strain curve (250 strain curves/view) and displayed on 3D rendered maps. The site of earliest activation & successful VE ablation was defined as ground truth for VE SOO.Results:10 patients were enrolled: 50% male, age 40.8 +/- 18.1 years, LV EF 41+/-15%, 50% with scar on MRI. CT ECGi correctly identified the VE AHA segment in 8/10 (80%) cases (misclassified 2 papillary muscle (PM) VEs) but did not afford transmural localization. After excluding 1 patient with insufficient VE’s for EWI, EWI correctly identified the VE-SOO segment in 8/9 (88%) cases locating 2 subepicardial, 2 septal intramural & 3 VEs at the base or intramural segment adjacent to a PM. It misclassified 1 PM VE.ConclusionBoth EWI & ECGI identified the VE-SOO segment in at least 80% of cases irrespective of presence of scar. EWI also correctly determined the transmural VE origin which cannot be located using commercial ECGI. This has important implications in planning ablation procedures.

Circulation, Volume 148, Issue Suppl_1, Page A13313-A13313, November 6, 2023. Background:Despite some shared risk factors, aortic aneurysms and atherosclerosis manifest differently across the aorta. While atherosclerosis commonly co-exists with descending and abdominal aortic aneurysms, some observations suggested a decreased risk of atherosclerosis in patients with ascending aortic aneurysms. This has led to the suggestion that drivers of ascending aortic aneurysms may be anti-atherogenic.Aim:Using carotid intima-media thickness (cIMT) as a surrogate for atherosclerosis and deep learning-derived estimates of aortic diameter, this study examines whether ascending aortic aneurysms are protective against atherosclerosis in a longitudinal analysis of UK Biobank participants.Methods:Individuals who underwent both carotid ultrasound and cardiovascular MRI in the UK Biobank (N=40,479) were identified. We derived ascending and descending aortic measurements from a previously developed deep learning model that was trained to quantify dimensions in >4 million MRI images and extract diameter during ventricular systole. Measures of mean cIMT at 2 standardized angles for bilateral carotid arteries were utilized. The relationship between cIMT and aortic diameter was assessed using univariable and multivariable linear regression. β was calculated as μm change in cIMT per cm of aortic diameter.Results:In individuals with an aneurysmal ascending aorta ( >4.5cm), there was no significant association between aortic diameter and cIMT after accounting for age, sex, height, and weight (adjusted β=-15.4, P=0.26). There was also no significant correlation between ascending aortic diameter at baseline and cIMT progression in follow-up (adjusted β=-2.5; P=0.48). In the entire cohort, larger ascending aortic size was nominally associated with greater cIMT (adjusted β=5.0; P=0.005). As expected, larger diameter in the descending thoracic aorta was associated with higher cIMT (adjusted β=23.9; P=1.9×10-16).Conclusion:Based on multi-modal imaging data from over 40K individuals, we find no evidence of an inverse relationship between ascending aortic aneurysmal disease and atherosclerosis.

Circulation, Volume 148, Issue Suppl_1, Page A14282-A14282, November 6, 2023. Introduction:The diagnostic performance of EKG in ruling out myocardial abnormalities following COVID-19 is unclear.Aim:To assess the ability of EKG to exclude cardiac abnormalities on cardiac magnetic resonance imaging (CMR) in post-hospitalised COVID-19 patients.Methods:Post-hospitalized patients (n=212) & comorbidities matched controls (n=38) underwent CMR and 12-lead EKG. EKG assessments included depolarization & repolarization abnormalities [QTc, corrected QT dispersion (QTc disp), JT (JTc) & T peak-end (cTPe) intervals]. CMR abnormalities were defined as reduced left ventricular ejection fraction (LVEF), high T1 & T2 Z scores and high extracellular volume and pathological late gadolinium enhancement.Results:At 5.6 months post-discharge, patients had a higher burden of EKG abnormalities vs controls (72.2% vs 42.1%, p=0.001) (Figure A). CMR abnormalities were comparable despite patients having lower LVEF. Abnormal EKG findings and prolonged repolarization were more common in patients with CMR abnormalities vs patients with normal CMR and controls (Figure A & B). Area-under-the-receiver-operating curve (AUROC) of routine EKG abnormalities to discriminate abnormal CMR was 0.56 (95% CI 0.47-0.65), p=0.185. Inclusion ofJTc&QTc dispimproved the AUROC to 0.64 (95% CI 0.55-0.74), p=0.002. Inclusion ofJTc ≥340ms&QTc disp≥40msimproved the sensitivity from 81.6% to 99.9% with higher negative predictive value (84.7% to 99.9%) (Figure A).Conclusions:Post-hospitalized COVID-19 patients have more EKG abnormalities than comorbidities-matched controls. A normal EKG with normal repolarization is effective in ruling out significant CMR abnormalities.

Circulation, Volume 148, Issue Suppl_1, Page A16513-A16513, November 6, 2023. Introduction:In contrast to normal chest X-ray, lung computed tomography (CT), and physiological lung and cardiac functions, many patients with long COVID syndrome suffer from shortness of breath.Hypothesis:The aim of this study was to quantify the pulmonary blood and airway volumes of long COVID patients compared with that of healthy controls.Methods:Patients with long COVID syndromes were included if they had PCR-verified previous (≥3 months) SARS-CoV-2 infection, had normal laboratory (e.g. inflammation, coagulation, cardiac or other organ) parameter, normal pulmonary morphology (chest X-ray and CT) and function (spirometry and body plethysmography). The lung CT images were postprocessed by Functional Respiratory imaging analysis by using 3D reconstruction with automated lung vessel segmentation algorithm. Data of the quantitative images were compared with age, gender, and BMI-matched healthy controls.Results:Thirty patients (45±13 years, 37% male, 25.9±4.3 kg/m^2) at a median time of 256 (118-574) days after a confirmed COVID infection and 30 healthy controls (55±7y, 37% male, 26.3±2.7 kg/m^2) were included. All long COVID patients complained of dyspnoea and 14 (48.3%) patients reported thoracic pain. The total pulmonary blood volume was significantly lower in the long COVID patients compared to controls (190±24.3 mL/m^2 vs230.6±26.2 ml/m^2, p

Circulation, Volume 148, Issue Suppl_1, Page A12256-A12256, November 6, 2023. Introduction:Liver fibrosis is associated with heart failure and left ventricular diastolic dysfunction. The fibrosis 4 (FIB-4) index is calculated from transaminases, age, and platelet count and can be used to screen patients with liver fibrosis. The myocardial extracellular volume fraction (ECVf) can be evaluated using contrast-enhanced cardiac magnetic resonance imaging (CMR).Hypothesis:ECVf is increased in patients with high FIB-4 index.AIMS:This study aimed to clarify the association between FIB-4 index and ECVf.Methods:A retrospective analysis was performed on patients aged ≥ 45 years with left ventricular ejection fraction (LVEF) > 40 % who underwent CMR at two Japanese institutions. Patients were divided into 3 groups according to the FIB-4 index: Low: FIB-4 index < 1.3; Intermediate: 1.3 ≤ FIB-4 index < 2.67; High: 2.67 ≤ FIB-4 index. The association between the FIB-4 index and ECVf was evaluated using multiple regression analysis, with the FIB-4 index treated as a continuous and nominal variable.Results:A total of 244 patients were included in the analysis, 136 of whom underwent contrast-enhanced CMR and could be evaluated for ECVf. The ECVf of the high FIB-4 index group was significantly higher than that of the other two groups (High: 31.0 ± 4.3 %; Intermediate: 27.9 ± 3.4 %; Low: 27.6 ± 3.7 %. High vs. Intermediate, p = 0.014; High vs. Low, p = 0.008; Intermediate vs. Low, p = 0.65). Multivariate analysis showed that both the FIB-4 index (continuous variable) and high FIB-4 index (nominal variable) were associated with higher ECVf (continuous variable, p = 0.043; nominal variable, p = 0.016).Conclusions:The high FIB-4 index was independently associated with increased ECVf. In contrast, patients with the intermediate FIB-4 index did not have increased ECVf. These suggested the usefulness of FIB-4 index as a cardiac fibrotic parameter.