Extracellular Volume Quantification Research Articles

Imaging of Cardiac Fibrosis: An Update, From the AJR Special Series on Imaging of Fibrosis.

Myocardial fibrosis (MF) is defined as excessive production and deposition of extra-cellular matrix (ECM) proteins that result in pathologic myocardial remodeling. Three types of MF have been identified: replacement fibrosis from tissue necrosis, reactive fibrosis from myocardial stress, and infiltrative interstitial fibrosis from progressive deposition of nondegradable material such as amyloid. Although echocardiography, nuclear medicine, and CT play important roles in the assessment of MF, MRI is pivotal in the evaluation of MF, with the late gadolinium enhancement (LGE) technique used as a primary end point. The LGE technique focuses on the pattern and distribution of gadolinium accumulation in the myocardium and assists in the diagnosis and establishment of the cause of both ischemic and nonischemic cardiomyopathy. LGE MRI also aids prognostication and risk stratification. In addition, LGE MRI is used to guide the management of patients considered for ablation for arrhythmias. Parametric mapping techniques, including T1 mapping and extracellular volume measurement, allow detection and quantification of diffuse fibrosis, which may not be detected by LGE MRI. These techniques also allow monitoring of disease progression and therapy response. This review provides an update on the imaging of MF, including prognostication and risk stratification tools, electrophysiologic considerations, and disease monitoring.

T1 and T2-mapping in pancreatic MRI: Current evidence and future perspectives

Conventional T1- and T2-weighted magnetic resonance imaging (MRI) of the pancreas can vary significantly due to factors such as scanner differences and pulse sequence variations. This review explores T1 and T2 mapping techniques, modern MRI methods providing quantitative information about tissue relaxation times. Various T1 and T2 mapping pulse sequences are currently under investigation. Clinical and research applications of T1 and T2 mapping in the pancreas include their correlation with fibrosis, inflammation, and neoplasms. In chronic pancreatitis, T1 mapping and extracellular volume (ECV) quantification demonstrate potential as biomarkers, aiding in early diagnosis and classification. T1 mapping also shows promise in evaluating pancreatic exocrine function and detecting glucose metabolism disorders. T2* mapping is valuable in quantifying pancreatic iron, offering insights into conditions like thalassemia major. However, challenges persist, such as the lack of consensus on optimal sequences and normal values for healthy pancreas relaxometry. Large-scale studies are needed for validation, and improvements in mapping sequences are essential for widespread clinical integration. The future holds potential for mixed qualitative and quantitative models, extending the applications of relaxometry techniques to various pancreatic lesions and enhancing routine MRI protocols for pancreatic pathology diagnosis and prognosis.

Prognostic value of measurement of myocardial extracellular volume using dual-energy CT in heart failure with preserved ejection fraction

Diffuse myocardial fibrosis is associated with adverse outcomes in heart failure with preserved ejection fraction (HFpEF). Dual-energy CT (DECT) can noninvasively assess myocardial fibrosis by quantification of extracellular volume (ECV) fraction. This study evaluated the association between ECV measured by DECT and clinical outcomes in patients with HFpEF. 125 hospitalized HFpEF patients were enrolled in this retrospective cohort study. ECV was measured using DECT with late iodine enhancement. The composite endpoint was defined as HFpEF hospitalization and all-cause mortality during the follow-up. During the median follow-up of 10.4 months, 34 patients (27.20%) experienced the composite outcomes, including 5 deaths; and 29 HFpEF hospitalizations. The higher DECT-ECV group had higher rates of composite outcomes than the low ECV group (log-rank X2 = 6.818, P = 0.033). In multivariate Cox regression analysis, the ECV (HR 1.17, 95% CI 1.06–1.30, P = 0.001) and NT-pro BNP (HR 2.83, 95% CI 1.16–6.88, P = 0.022) were independent risk factors for the adverse outcomes. Myocardial ECV measured using DECT was an independent risk factor for adverse outcomes in patients with HFpEF.

Assessing Regurgitation Severity, Adverse Remodeling, and Fibrosis with CMR in Aortic Regurgitation.

Cardiac magnetic resonance (CMR) is emerging as a valuable imaging modality for the assessment of aortic regurgitation (AR). In this review, we discuss the assessment of AR severity, left ventricular (LV) remodeling, and tissue characterization by CMR while highlighting the latest studies and addressing future research needs. Recent studies have further established CMR-based thresholds of AR severity and LV remodeling that are associated with adverse clinical outcomes, and lower than current guideline criteria. In addition, tissue profiling with late gadolinium enhancement (LGE) and extracellular volume (ECV) quantification can reliably assess adverse myocardial tissue remodeling which is also associated with adverse outcomes. The strengths and reproducibility of CMR in evaluating ventricular volumes, tissue characteristics, and regurgitation severity position it as an excellent modality in evaluating and following AR patients. Advanced CMR techniques for the detection of tissue remodeling have shown significant potential and merit further investigation.

Quantitating myocardial fibrosis using extracellular extravascular volume determined from computed tomography myocardial perfusion imaging

PurposeBoth of extracellular extravascular volume (EEV) and extracellular volume fraction (ECV) were proposed to quantify enlargement of myocardial interstitial space due to myocardium loss or fibrosis. The study aimed to investigate the feasibility of using EEV derived from myocardial computed tomography (CT) perfusion imaging (VPCT) and extracellular volume quantification with single-energy subtraction CT (ECV− SECT) for quantifying myocardial fibrosis.MethodsIn this study, 17 patients with suspected and known coronary artery disease underwent examination using a dual-source CT scanner. The EEV− VPCT was derived from dynamic whole-heart myocardial perfusion imaging, and the ECV_SECT was calculated from late-enhanced images 5 min after bolus contrast injection by subtracting the noncontrast baseline. The late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging was used as a reference.ResultsIn total, 11 patients and 73 segments exhibited positivity for LGE on CMR imaging. These were classified into three groups according to the segments: fibrotic segments (group I, n = 73), nonfibrotic segments in LGE-positive patients (group II, n = 103), and segments in LGE-negative patients (group III, n = 80). ECV− SECT, EEV− VPCT, myocardial blood flow (MBF), and myocardial blood volume (MBV) significantly differed among these groups (all P < 0.05). ECV− SECT was significantly higher and EEV− VPCT, MBF, and MBV were significantly lower in fibrotic myocardial segments than in nonfibrotic ones (all P < 0.01). ECV− SECT and EEV− VPCT independently affected myocardial fibrosis. There was no significant correlation between ECV− SECT and EEV− VPCT. The capability of EEV− VPCT to diagnose myocardial fibrosis was equivalent to that of ECV− SECT (area under the curve: 0.798 vs. 0.806, P = 0.844). ECV− SECT of > 41.2% and EEV− VPCT of < 10.3% indicated myocardial fibrosis.ConclusionsEEV− VPCT is actually first-pass distribution volume that can feasibly be used to quantify myocardial fibrosis. Furthermore, the diagnostic efficacy of EEV− VPCT is comparable to that of ECV− SECT.

Amyloid Burden Correlates with Electrocardiographic Findings in Patients with Cardiac Amyloidosis-Insights from Histology and Cardiac Magnetic Resonance Imaging.

Cardiac amyloidosis (CA) is associated with several distinct electrocardiographic (ECG) changes. However, the impact of amyloid depositions on ECG parameters is not well investigated. We therefore aimed to assess the correlation of amyloid burden with ECG and test the prognostic power of ECG findings on outcomes in patients with CA. Consecutive CA patients underwent ECG assessment and cardiac magnetic resonance imaging (CMR), including the quantification of extracellular volume (ECV) with T1 mapping. Moreover, seven patients underwent additional amyloid quantification using immunohistochemistry staining of endomyocardial biopsies. A total of 105 CA patients (wild-type transthyretin: 74.3%, variant transthyretin: 8.6%, light chain: 17.1%) were analyzed for this study. We detected correlations of total QRS voltage with histologically quantified amyloid burden (r = -0.780, p = 0.039) and ECV (r = -0.266, p = 0.006). In patients above the ECV median (43.9%), PR intervals were significantly longer (p = 0.016) and left anterior fascicular blocks were more prevalent (p = 0.025). In our survival analysis, neither Kaplan-Meier curves (p = 0.996) nor Cox regression analysis detected associations of QRS voltage with adverse patient outcomes (hazard ratio: 0.995, p = 0.265). The present study demonstrated that an increased amyloid burden is associated with lower voltages in CA patients. However, baseline ECG findings, including QRS voltage, were not associated with adverse outcomes.

Kiosk 7R-TA-02 - Extracellular Volume Quantification Using Synthetic Hematocrit in Cardiac Amyloidosis

Kiosk 7R-TA-02 - Extracellular Volume Quantification Using Synthetic Hematocrit in Cardiac Amyloidosis

Utility of Photon Counting CT in Transcatheter Structural Heart Disease Interventions

Photon counting Computed Tomography (PCCT) is an innovative technology that utilizes a semiconductor detector and assigns x-ray photons to specific energy bins. PCCT features include ultra high-resolution, multi-energy binning, higher signal of iodine, lower artifacts, lower noise, and geometric radiation dose efficiency. These advantages may be highly beneficial in pre- and post-procedural assessment of transcatheter structural heart disease (SHD) interventions. Ultra-high resolution improves visualization of device structure and subtle findings such as hypoattenuated leaflet thickening, small vegetations and paravalvular leaks. High resolution also improves the evaluation of heavily calcified and stented coronary arteries, which are prevalent in high-risk transcatheter aortic valve replacement (TAVR) population. Visualization of heavily calcified coronary arteries and access vessels can also be improved by using multienergy calcium separation or high-energy virtual monoenergetic images (VMIs). PCCT allows use of low dose of iodinated contrast in severe renal dysfunction, due to inherent higher contrast-to-noise ratio of iodine, availability of a high-pitch helical mode and low-energy VMIs. High-energy VMIs can decrease artifacts including calcium blooming, beam hardening and metallic artifacts. Iodine maps enable quantification of extracellular volume without need for a non-contrast scan, facilitating the identification of cardiomyopathies like cardiac amyloidosis. Moreover, calcium score can be obtained from virtual non contrast (VNC) images derived from CT angiographic images. Additionally, VNC and iodine maps can characterize incidentally encountered lesions such as thrombus. In this article, we review the utility of PCCT in transcatheter SHD interventions.

Quantification of extracellular volume with cardiac computed tomography in patients with left ventricle dysfunction

Abstract Background Myocardial fibrosis (MF) is a common endpoint in the majority of pathological mechanisms affecting cardiac muscle, ultimately resulting in cardiac failure. Cardiovascular magnetic resonance (CMR) with gadolinium-based contrast agent and T1 mapping technique is able to deliver a non-invasive quantification of the extracellular volume (ECV) expansion. Recently, ECV estimation with cardiac computed tomography (ECV-CCT) has been validated in the setting of cardiac amyloidosis, showing good agreement with ECV-CMR. However, no evidence is available with last generation single source single energy CT scanner in the clinical context of newly diagnosed left ventricular dysfunction. Therefore, the aim of this study is to test the diagnostic accuracy of ECV-CCT for the detection of MF in patients with recent diagnosis of reduced left ventricle ejection fraction (LVEF), having ECV-CMR as reference technique. Methods A consecutive cohort of 41 patients with newly diagnosed left ventricle dysfunction (LVEF &amp;lt; 50%) was enrolled. Time interval of maximum 30 days was present between CCT and CMR. Myocardial segment evaluability with each technique, agreement between ECV-CMR and ECV-CCT, regression analysis and Bland-Altman analysis were performed. Results Age of enrolled patients was 62 ± 11 years, and mean LVEF at CMR was 35.2 ± 10.7%. Mean total amount of administrated iodinated contrast was 112.6 ± 22.2 ml, while overall radiation exposure for ECV estimation was2.1 ± 1.1 mSv. Out of 656 myocardial segments available, 656 (100%) segments were evaluable at CCT while 640 (97.6%) were evaluable at CMR. ECV-CCT demonstrated slightly lower values compared to ECV-CMR both at global and region-based comparison (all segments, 33.1 ± 8.5% vs 35.5 ± 10.7%, p &amp;lt; 0.001). At regression analysis, strong correlations were described both at global and region-based analysis (all segments, r = 0.877, 95% CI: 0.840 to 0.914). On Bland-Altman analysis, bias between ECV-CMR and ECV-CCT for global analysis was 2.4 (95% CI: -7.8 to 12.7). Conclusions ECV estimation with last-generation single source single energy CT scanner is feasible and accurate. Integration of ECV measurement in comprehensive CCT evaluation of patients with newly diagnosed left ventricular dysfunction can be performed with a small increase in overall radiation exposure.

Myocardial structural and functional changes in cardiac amyloidosis - insights from a prospective observational patient registry

Abstract Background Within the last decade, cardiac amyloidosis (CA) has been acknowledged as a significant cause of heart failure and patients who are affected face a dismal prognosis, especially in later stages of the disease. The pathophysiological hallmark of cardiac amyloidosis (CA) is the deposition of amyloid within the myocardium. Consequently, extracellular volume (ECV) of affected patients increases. However, studies on ECV progression over time and its' impact on prognosis are lacking. Objectives We aimed to investigate the progression of ECV and its prognostic impact in CA patients. Methods Serial cardiac magnetic resonance (CMR) examinations, including ECV quantification were performed in consecutive CA patients. Results Between 2012 and 2021, 103 CA patients underwent baseline and follow-up CMR, including ECV quantification. Median ECVs at baseline of the total (n = 103), transthyretin [(ATTR) n = 80], and [light chain (AL) n = 23] CA cohorts were 48.0%, 49.0%, and 42.6%. During a median follow-up period of 12 months, ECV increased significantly in all cohorts (48.0% to 50.5%, p&amp;lt;0.001; 49.0% to 50.5%, p&amp;lt;0.001; 42.6% to 50.6%, p = 0.026). Separate analyses for treatment-naïve (n = 14) and treated (n = 66) ATTR patients revealed that the median change of ECV from baseline to follow-up was significantly higher among untreated patients (5.5% versus 2.7%, p = 0.035). Survival analyses demonstrated that median change of ECV was an independent (adjusted for troponin t and NT-proBNP) predictor of outcome in all CA cohorts [total: hazard ratio (HR): 1.114, 95% confidence-interval (CI): 1.045 – 1.189, p&amp;lt;0.001; ATTR: HR: 1.099, 95% CI: 1.014 – 1.192, p = 0.022; AL: HR: 1.142, 95% CI: 1.006 – 1.297, p = 0.040]. Conclusions The present study demonstrates that ECV, quantified by CMR T1 mapping, increases significantly in CA patients over the course of 12 months. While ECV increased, irrespective of amyloid type our analyses showed the highest increase among untreated ATTR patients. Moreover, the change of ECV was an independent predictor of adverse outcomes in AL, as well as ATTR patients emphasizing the usefulness of CMR T1 mapping in the management of CA patients.Figure 1.Dot PlotsFigure 2.Kaplan Meier Curves

Myocardial native T1 mapping and extracellular volume quantification in asymptomatic female carriers of Duchenne muscular dystrophy gene mutations

BackgroundFemale carriers of dystrophin gene mutations (DMD-FC) were previously considered non-manifesting, but in recent decades, cardiomyopathy associated with muscular dystrophy and myocardial fibrosis has been described. Our study aimed to assess prospectively myocardial fibrosis in asymptomatic DMD-FC compared to a sex-matched control group (CG) with similar age distribution using native T1 mapping and extracellular volume (ECV) quantification by cardiovascular magnetic resonance (CMR) imaging.Materials and methods38 DMD-FC with verified genetic mutation and 22 healthy volunteers were included. Using CMR, native T1 relaxation time and ECV quantification were determined in each group. Late gadolinium enhancement (LGE) was assessed in all cases.ResultsThere were 38 DMD-FC (mean age 39.1 ± 8.8 years) and 22 healthy volunteers (mean age 39.9 ± 12.6 years) imagined by CMR. The mean global native T1 relaxation time was similar for DMD-FC and CG (1005.1 ± 26.3 ms vs. 1003.5 ± 25.0 ms; p-value = 0.81). Likewise, the mean global ECV value was also similar between the groups (27.92 ± 2.02% vs. 27.10 ± 2.89%; p-value = 0.20). The segmental analysis of mean ECV values according to the American Heart Association classification did not show any differences between DMD-FC and CG. There was a non-significant trend towards higher mean ECV values of DMD-FC in the inferior and inferolateral segments of the myocardium (p-value = 0.075 and 0.070 respectively).ConclusionThere were no statistically significant differences in the mean global and segmental native T1 relaxation times and the mean global or segmental ECV values. There was a trend towards higher segmental mean ECV values of DMD-FC in the inferior and inferolateral walls of the myocardium.

Quantification of myocardial extracellular volume without blood sampling.

Cardiac magnetic resonance (CMR) T1 relaxation time mapping is an established technique primarily used to identify diffuse interstitial fibrosis and oedema. The myocardial extracellular volume (ECV) can be calculated from pre- and post-contrast T1 relaxation times and is a reproducible parametric index of the proportion of volume occupied by non-cardiomyocyte components in myocardial tissue. The conventional calculation of the ECV requires blood sampling to measure the haematocrit (HCT). Given the high variability of the HCT, the blood collection is recommended within 24 h of the CMR scan, limiting its applicability and posing a barrier to the clinical routine use of ECV measurements. In recent years, several research groups have proposed a method to determine the ECV by CMR without blood sampling. This is based on the inverse relationship between the T1 relaxation rate (R1) of blood and the HCT. Consequently, a 'synthetic' HCT could be estimated from the native blood R1, avoiding blood sampling. We performed a review and meta-analysis of published studies on synthetic ECV, as well as a secondary analysis of previously published data to examine the effect of the chosen regression modell on bias. While, overall, a good correlation and little bias between synthetic and conventional ECV were found in these studies, questions regarding its accuracy remain. Synthetic HCT and ECV can provide a 'non-invasive' quantitative measurement of the myocardium's extracellular space when timely HCT measurements are not available and large alterations in ECV are expected, such as in cardiac amyloidosis. Due to the dependency of T1 relaxation times on the local setup, calculation of local formulas using linear regression is recommended, which can be easily performed using available data.

Myocardial extracellular volume quantification in cardiac amyloidosis: a comparative study between cardiac computed tomography and magnetic resonance imaging.

Myocardial extracellular volume (ECV) on computed tomography (CT), an alternative to cardiac magnetic resonance (CMR), has significant practical clinical advantages. However, the consistency between ECVs quantified via CT and CMR in cardiac amyloidosis (CA) has not been investigated sufficiently. Therefore, the current study investigated the application of CT-ECV in CA with CMR-ECV as the reference standard. We retrospectively evaluated 31 patients with CA who underwent cardiac CT and CMR. Pearson correlation analysis was performed to investigate correlations between CT-ECV and CMR-ECV at each segment. Further, correlations between ECV and clinical parameters were assessed. There were no significant differences in the mean global ECVs between CT scan and CMR (51.3% ± 10.2% vs 50.0% ± 10.5%). CT-ECV was correlated with CMR-ECV at the septal (r = 0.88), lateral (r = 0.80), inferior (r = 0.79), anterior (r = 0.77) segments, and global (r = 0.87). In both CT and CMR, the ECV had a weak to strong correlation with high-sensitivity cardiac troponin T level, a moderate correlation with global longitudinal strain, and an inverse correlation with left ventricular ejection fraction. Further, the septal ECV and global ECV had a slightly higher correlation with the clinical parameters. Cardiac CT can quantify myocardial ECV and yield results comparable to CMR in patients with CA. Moreover, a significant correlation between CT-ECV and clinical parameters was observed. Thus, CT-ECV can be an imaging biomarker and alternative to CMR-ECV. Cardiac CT can quantify myocardial ECV and yield results comparable to CMR in patients with CA, and CT-ECV can be used clinically as an imaging biomarker and alternative to CMR-ECV. • A significant correlation was found between CT myocardial extracellular volume and cardiac MR myocardial extracellular volume in patients with cardiac amyloidosis. • In CT and cardiac MR, the myocardial extracellular volume correlated well with high-sensitivity cardiac troponin T level, global longitudinal strain, and left ventricular ejection fraction. • CT myocardial extracellular volume can be an imaging biomarker and alternative to cardiac MR myocardial extracellular volume.

Quantification Of Extracellular Volume With Cardiac Computed Tomography In Patients With Left Ventricle Dysfunction

Quantification Of Extracellular Volume With Cardiac Computed Tomography In Patients With Left Ventricle Dysfunction

Myocardial Extra-cellular Volume Quantification By Computed Tomography Predicts Medium-term Outcome In Aortic Stenosis Patients Undergoing Tavr

Myocardial Extra-cellular Volume Quantification By Computed Tomography Predicts Medium-term Outcome In Aortic Stenosis Patients Undergoing Tavr

CT for the evaluation of myocardial extracellular volume with MRI as reference: a systematic review and meta-analysis.

Myocardial extracellular volume (ECV) fraction is an important imaging biomarker in clinical decision-making. CT-ECV is a potential alternative to MRI for ECV quantification. We conducted a meta-analysis to comprehensively assess the reliability of CT for ECV quantification with MRI as a reference. We systematically searched PubMed, EMBASE, and the Cochrane Library for relevant articles published since the establishment of the database in July 2022. The articles comparing CT-ECV with MRI as a reference were included. Meta-analytic methods were applied to determine the pooled weighted bias, limits of agreement (LOA), and correlation coefficient (r) between CT-ECV and MRI-ECV. Seventeen studies with a total of 459 patients and 2231 myocardial segments were included. The pooled mean difference (MD), LOA, and r for ECV quantification at the per-patient level was (0.07%; 95% LOA: - 0.42 to 0.55%) and 0.89 (95% CI: 0.86-0.91), respectively, while on the per-segment level was (0.44%; 95% LOA: 0.16-0.72%) and 0.84 (95% CI: 0.82-0.85), respectively. The pooled r from studies with the ECViodine method for ECV quantification was significantly higher compared to those with the ECVsub method (0.94 (95% CI: 0.91-0.96) vs. 0.84 (95% CI: 0.80-0.88), respectively, p = 0.03). The pooled r from septal segments was significantly higher than those from non-septal segments (0.88 (95% CI: 0.86-0.90) vs. 0.76 (95% CI: 0.71-0.90), respectively, p = 0.009). CT showed a good agreement and excellent correlation with MRI for ECV quantification and is a potentially attractive alternative to MRI. Themyocardial extracellular volume fractioncan be acquired using a CT scan, which is not only a viable alternative to myocardial extracellular volume fraction derived from MRI but is also less time-consuming and costly for patients. • Noninvasive CT-ECV is a viable alternative to MRI-ECV for ECV quantification. • CT-ECV using the ECViodine method showed more accurate myocardial ECV quantification than ECVsub. • Septal myocardial segments showed lower measurement variability than non-septal segments for the ECV quantification.

Quantification of extracellular volume with cardiac computed tomography in patients with left ventricle dysfunction

Abstract Funding Acknowledgements Type of funding sources: None. Background Myocardial fibrosis (MF) is a common endpoint in the majority of pathological mechanisms affecting cardiac muscle, ultimately resulting in cardiac failure. Cardiovascular magnetic resonance (CMR) with gadolinium-based contrast agent and T1 mapping technique is able to deliver a non-invasive quantification of the extracellular volume (ECV) expansion. Recently, ECV estimation with cardiac computed tomography (ECV-CCT) has been validated in the setting of cardiac amyloidosis, showing good agreement with ECV-CMR. However, no evidence is available with last generation single source single energy CT scanner in the clinical context of newly diagnosed left ventricular dysfunction. Therefore, the aim of this study is to test the diagnostic accuracy of ECV-CCT for the detection of MF in patients with recent diagnosis of reduced left ventricle ejection fraction (LVEF), having ECV-CMR as reference technique. Methods A consecutive cohort of 41 patients with newly diagnosed left ventricle dysfunction (LVEF &amp;lt; 50%) was enrolled. Time interval of maximum 30 days was present between CCT and CMR. Myocardial segment evaluability with each technique, agreement between ECV-CMR and ECV-CCT, regression analysis and Bland-Altman analysis were performed. Results Age of enrolled patients was 62 ± 11 years, and mean LVEF at CMR was 35.2 ± 10.7%. Mean total amount of administrated iodinated contrast was 112.6 ± 22.2 ml, while overall radiation exposure for ECV estimation was 2.1 ± 1.1 mSv. Out of 656 myocardial segments available, 656 (100%) segments were evaluable at CCT while 640 (97.6%) were evaluable at CMR. ECV-CCT demonstrated slightly lower values compared to ECV-CMR both at global and region-based comparison (all segments, 33.1 ± 8.5% vs 35.5 ± 10.7%, p &amp;lt; 0.001). At regression analysis, strong correlations were described both at global and region-based analysis (all segments, r = 0.877, 95%CI: 0.840 to 0.914). On Bland-Altman analysis, bias between ECV-CMR and ECV-CCT for global analysis was 2.4 (95%CI: −7.8 to 12.7). Conclusions ECV estimation with last-generation single source single energy CT scanner is feasible and accurate. Integration of ECV measurement in comprehensive CCT evaluation of patients with newly diagnosed left ventricular dysfunction can be performed with a small increase in overall radiation exposure.

The importance of the imaging methods in patients with COVID-19 infection

Abstract Funding Acknowledgements Type of funding sources: None. Background Echocardiography, pulmonary CT and cardiac magnetic resonance (CMR) were have been used in detecting organ damage in COVID-19 patients. The aim of this study is to compare imaging findings and clinical symptoms patients with COVID-19. Methods The study was conducted in our university clinical center. All pts underwent clinical examination, laboratory analysis, echocardiography, pulmonary CT and CMR. Results 126 pts with COVID-19 infection, 61 (48%) male, mean age 45±15years with symptoms of palpitation, fatigue, dyspnea and chest pain. Meantime from the onset of infection to observation was 107 days. In pts with palpitation, brain natriuretic peptide (NTproBNP) was not higher (39.4±9.1 vs. 19.2±9.4 pg/ml, p = 0.075). In case of pts with dyspnea ejection fraction of the left ventricle (LVEF) as founded by echocardiography, was significantly lower (62±6 vs. 67±6%, p = 0.025). The CT severity score index was not significantly higher in patients with fatigue after acute infection (21.0±8.1 vs. 10.1±5.1, p = 0.060). Late gadolinium enhancement (LGE) was seen in 61/126 (48%) pts, distribution was predominantly in mid and epicardial layers 41/61 pts (67%), &amp;gt;3 segments were identified in 37/61 pts (61%), myocardial edema was seen in 50/126 pts (40%). The extracellular volume (ECV) quantification by CMR were significantly higher in patients with fatigue (22.6±3.8 vs. 19.7±5.2%, p = 0.010). There is no significant correlation between clinical symptoms and myocardial oedema by using T2FS. Conclusions Echocardiography and CMR are the most important imaging methods in risk stratification and optimal therapeutic strategies in pts with myocardial injury caused by COVID-19 infection.

Tracking multi-organ treatment response in systemic AL amyloidosis with cardiac magnetic resonance derived extracellular volume mapping

Abstract Funding Acknowledgements Type of funding sources: None. Background Systemic light-chain (AL) amyloidosis commonly involves the liver, spleen and heart. Cardiac magnetic resonance (CMR) with extracellular volume (ECV) mapping has demonstrated accuracy in measuring cardiac, hepatic and splenic amyloid infiltration. Purpose We sought to: (1) assess the association between baseline multi-organ ECVs and prognosis (2) assess the multi-organ response to treatment using ECV mapping, and (3) assess the association between multi-organ treatment response and prognosis. Methods We identified 351 patients with a confirmed diagnosis of systemic AL amyloidosis who underwent baseline serum amyloid P component (SAP) scintigraphy and CMR at diagnosis, of which 171 had follow-up imaging. We also recruited 20 healthy volunteers who underwent CMR with ECV mapping, without corresponding SAP scintigraphy, to allow calculation of the ECV normal ranges. Results At diagnosis, ECV mapping demonstrated that 304(86.7%) had cardiac involvement, 114(32.5%) significant hepatic involvement and 147(41.9%) significant splenic involvement. Baseline myocardial and liver ECV independently predict mortality (myocardial: HR=1.05,95CI%[1.03–1.07],P&amp;lt;0.001; liver: HR=1.03,95%CI[1.01–1.05],P&amp;lt;0.001). Liver and spleen ECV correlated with amyloid load assessed by SAP scintigraphy (R=0.751,P&amp;lt;0.001; R=0.765,P&amp;lt;0.001, respectively). Serial multi-organ ECV measurements accurately tracked treatment response as validated against serial SAP scintigraphy (the current reference standard). Multi-organ ECV regression was observed as early as 6-months in patients with a good haematological response (liver=15%, spleen=15%, heart=5%). The remaining patients with a good haematological response had stable liver and spleen ECVs, but 20% had cardiac progression. By 12-months more patients with a good haematological response demonstrated cardiac regression (liver=30%, spleen=36%, heart=32%), and this trend was maintained at 24-months. Multi-variable analysis adjusting for haematological response, change in myocardial, liver and spleen ECV demonstrated that haematological response, change in myocardial ECV (HR=1.11, 95%CI[1.02–1.19], P=0.011) and liver ECV (HR=1.06, 95%CI[1.01–1.11], P=0.015) remained independent predictors of prognosis at 6-months. Conclusions Multi-organ ECV quantification accurately tracks treatment response, and demonstrates different rates of organ regression, with the liver and spleen regressing more rapidly than the heart. A good haematological response alone is likely to induce visceral organ stabilisation/regression, but may not be sufficient to induce myocardial stabilisation/regression. Liver and myocardial ECV at diagnosis and changes in ECV at 6-months independently predict mortality. ECV mapping offers a comprehensive multi-organ assessment of treatment response and accurate prognostication.

Tracking Multiorgan Treatment Response in Systemic AL-Amyloidosis With Cardiac Magnetic Resonance Derived Extracellular Volume Mapping

BackgroundSystemic light chain amyloidosis is a multisystem disorder that commonly involves the heart, liver, and spleen. Cardiac magnetic resonance with extracellular volume (ECV) mapping provides a surrogate measure of the myocardial, liver, and spleen amyloid burden. ObjectivesThe purpose of this study was to assess multiorgan response to treatment using ECV mapping, and assess the association between multiorgan treatment response and prognosis. MethodsThe authors identified 351 patients who underwent baseline serum amyloid-P-component (SAP) scintigraphy and cardiac magnetic resonance at diagnosis, of which 171 had follow-up imaging. ResultsAt diagnosis, ECV mapping demonstrated that 304 (87%) had cardiac involvement, 114 (33%) significant hepatic involvement, and 147 (42%) significant splenic involvement. Baseline myocardial and liver ECV independently predict mortality (myocardial HR: 1.03 [95% CI: 1.01-1.06]; P = 0.009; liver HR: 1.03; [95% CI: 1.01-1.05]; P = 0.001). Liver and spleen ECV correlated with amyloid load assessed by SAP scintigraphy (R = 0.751; P < 0.001; R = 0.765; P < 0.001, respectively). Serial measurements demonstrated ECV correctly identified changes in liver and spleen amyloid load derived from SAP scintigraphy in 85% and 82% of cases, respectively. At 6 months, more patients with a good hematologic response had liver (30%) and spleen (36%) ECV regression than myocardial regression (5%). By 12 months, more patients with a good response demonstrated myocardial regression (heart 32%, liver 30%, spleen 36%). Myocardial regression was associated with reduced median N-terminal pro-brain natriuretic peptide (P < 0.001), and liver regression with reduced median alkaline phosphatase (P = 0.001). Changes in myocardial and liver ECV, 6 months after initiating chemotherapy, independently predict mortality (myocardial HR: 1.11 [95% CI: 1.02-1.20]; P = 0.011; liver HR: 1.07 [95% CI: 1.01-1.13]; P = 0.014). ConclusionsMultiorgan ECV quantification accurately tracks treatment response and demonstrates different rates of organ regression, with the liver and spleen regressing more rapidly than the heart. Baseline myocardial and liver ECV and changes at 6 months independently predict mortality, even after adjusting for traditional predictors of prognosis.