Myocardial FDG Uptake Research Articles

Prediction of cardiac events following concurrent chemoradiation therapy for non-small-cell lung cancer using FDG PET.

No imaging biomarkers are available for the prediction of cardiac events following concurrent chemoradiation therapy (CCRT) for non-small-cell lung cancer (NSCLC). We evaluated whether F-18 fluorodeoxyglucose positron emission tomography (FDG PET) early after CCRT, in addition to cardiac dosimetry, could predict late cardiac events in NSCLC. We retrospectively enrolled 133 consecutive patients with locally advanced, unresectable stage III NSCLC, who underwent FDG PET early after CCRT and survived at least 6months. The primary endpoint was cardiac event ≥ grade 2 according to the Common Terminology Criteria for Adverse Events (version 5.0). Myocardial FDG uptake was measured and its association with the risk of cardiac events was evaluated. FDG PET was performed after a median interval of 11days of completing CCRT. Overall, 42 (32%) patients experienced cardiac events during a median follow-up of 45months. The mean heart dose, maximum left ventricular (LV) standardized uptake value (SUV), changes in maximum and mean LV SUV, right ventricular uptake, tumor stage, white blood cell count, and diabetes were associated with cardiac events in univariable analysis. In multivariable analysis, maximum LV SUV (cutoff > 12.84; hazard ratio [95% confidence interval] = 2.140 [1.140-4.016]; p = 0.018) was an independent predictor of cardiac events along with the mean heart dose (> 11.1Gy; 3.646 [1.792-7.417]; p < 0.001) and tumor stage (IIIB; 1.986 [1.056-3.734]; p = 0.033). It remained predictive of cardiac events in those with higher mean heart dose but not in those with lower mean heart dose. Early FDG PET after CCRT for NSCLC could aid in predicting late cardiac events, especially in patients with higher mean heart dose.

The usefulness of repeated CMR and FDG PET/CT in the diagnosis of patients with initial possible cardiac sarcoidosis

BackgroundCardiac sarcoidosis (CS) diagnosis is usually based on advanced imaging techniques and multidisciplinary evaluation. Diagnosis is classified as definite, probable, possible or unlikely. If diagnostic confidence remains uncertain, cardiac imaging can be repeated. The objective is to evaluate the usefulness of repeated cardiac magnetic resonance imaging (CMR) and fluorodeoxyglucose positron emission tomography (FDG PET/CT) for CS diagnosis in patients with an initial “possible” CS diagnosis.MethodsWe performed a retrospective cohort study in 35 patients diagnosed with possible CS by our multidisciplinary team (MDT), who received repeated CMR and FDG PET/CT within 12 months after diagnosis. Imaging modalities were scored on abnormalities suggestive for CS and classified as CMR+/PET+, CMR+/PET−, CMR−/PET+ and CMR−/PET−. Primary endpoint was final MDT diagnosis of CS.ResultsAfter re-evaluation, nine patients (25.7%) were reclassified as probable CS and 16 patients (45.7%) as unlikely CS. Two patients started immunosuppressive treatment after re-evaluation. At baseline, eleven patients (31.4%) showed late gadolinium enhancement (LGE) on CMR (CMR+) and 26 (74.3%) patients showed myocardial FDG-uptake (PET+). At re-evaluation, nine patients (25.7%) showed LGE (CMR+), while 16 patients (45.7%) showed myocardial FDG-uptake (PET+). When considering both imaging modalities together, 82.6% of patients with CMR−/PET+ at baseline were reclassified as possible or unlikely CS, while 36.4% of patients with CMR+ at baseline were reclassified as probable CS. Three patients with initial CMR−/PET+ showed LGE at re-evaluation.ConclusionRepeated CMR and FDG PET/CT may be useful in establishing or rejecting CS diagnosis, when initial diagnosis is uncertain. However, clinical relevance has to be further determined.

Association Between Changes in Myocardial F-18 Fluorodeoxyglucose Uptake and Cardiac Toxicity or Overall Survival for Inoperable NSCLC Patients Receiving Chemoradiation

<h3>Purpose/Objective(s)</h3> Previous studies have shown that increased cardiac uptake of 18F-fluorodeoxyglucose (FDG) on positron emission tomography (PET) may be an indicator of myocardial injury after radiotherapy. Our study aimed to investigate the predictive value of changes in myocardial ¹⁸F-FDG uptake for cardiotoxicity and overall survival (OS) in patients with inoperable NSCLC receiving definitive chemoradiation. <h3>Materials/Methods</h3> One hundred and fifty unresectable locally advanced NSCLC patients enrolled in a retrospective study who had undergone pre- and post-chemoradiation FDG-PET imaging were evaluated. Our primary endpoint was grade ≥ 3 cardiac toxicity. Patient clinicopathologic factors, dosimetric parameters for the whole heart and cardiac substructures, and myocardial changes within the irradiated fields on 18F-FDG PET were utilized to seek the best predictive model for cardiotoxicity. Competing risk analysis and Cox regressions analysis were performed. <h3>Results</h3> At a median follow-up interval of 35 months, twenty-six patients (17.3%) developed grade ≥ 3 cardiac everts. Twenty-nine patients (19.3%) showed increased myocardial FDG uptake within the irradiated fields associated with the heart dosimetric parameters. The best multivariable model based on the lowest Akaike information criterion for predicting grade ≥ 3 cardiotoxicity included the following covariates: pre-existing cardiac disease, changes in pre- and post-chemoradiation myocardial SUV_mean (∆SUV_mean), and mean heart dose. Subanalysis showed that pre-existing cardiac disease, ∆SUV_mean, and mean left anterior descending dose were significantly associated with grade ≥ 3 acute coronary syndrome/congestive heart failure events. ∆SUV_mean and grade ≥ 3 cardiac toxicity were independent indicators of OS. <h3>Conclusion</h3> ∆SUV_mean was an independent indicator of grade ≥ 3 cardiac toxicity and OS in unresectable locally advanced NSCLC patients receiving definitive chemoradiation. Changes in myocardial uptake of FDG is a promising biomaker for predicting radiation-induced cardiotoxicity.

MAGIC OF ADVANCED IMAGING AND IMMUNOTHERAPY IN CARDIAC SARCOIDOSIS

TOPIC: Cardiovascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: This case report emphasizes the role of advanced imaging and immunotherapy in the diagnosis and management of cardiac sarcoidosis (CS). CASE PRESENTATION: A 52-year-old healthy male presented with near-syncope for 5 days. He had a blood pressure of 164/67 mmHg and a heart rate of 43 bpm. Electrocardiogram revealed complete-heart-block (CHB) with a ventricular rate of 38/min. Troponin T and electrolytes were normal, and Lyme's serology was negative. Echocardiogram was normal. Cardiac magnetic resonance imaging (CMR) revealed late gadolinium enhancement (LGE) affecting the mid inferior segment at the right ventricle (RV) insertion site (Figure 1). A cardiac and whole-body 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan showed focal areas of increased FDG uptake in the LV involving mid and basal anteroseptal segments, mid inferoseptal segment, basal inferolateral, and basal inferior segments with normal perfusion (Figure 2). The scan also revealed hypermetabolic bilateral hilar and mediastinal lymphadenopathy. A diagnosis of CS was made. An Implantable-Cardioverter-defibrillator (ICD) was placed and the patient was discharged on 40mg of prednisone and 20mg of leflunomide. Within 4 months, he went from 100% RV pacing to 0%. Eventually, the corticosteroid was tapered off. At follow-up after 1.5 years, RV pacing remained 0% on Leflunomide 20mg. DISCUSSION: One should always suspect CS in young patients with high-grade AV block. During the workup of CHB (Figure 3), the 2017 Japanese Circulation Society Working Group Criteria for diagnosing CS was followed (1). The patient had 2 characteristic findings strongly suggestive of sarcoidosis: (a) hilar lymphadenopathy and (b) significant tracer accumulation in the myocardium and hilar lymph nodes on FDG-PET scan. He also met 2 major criteria strongly suggestive of CS: (a) LGE on CMR and (b) abnormal myocardial FDG uptake. These findings, per the criteria, establish the clinical diagnosis of CS. The mainstay of treatment for CS is corticosteroids +/- steroid-sparing agents to decrease intra-cardiac inflammation (1). CHB patients with CS have a high risk of ventricular arrhythmias, hence should receive ICD (2). The addition of antimetabolite adjuvants is more effective than corticosteroids alone (3). They may reduce the total time of glucocorticoid therapy and keep patients in remission. CONCLUSIONS: Clinical diagnosis of CS can be established with FDG-PET imaging and CMR. CS patients with advanced heart block should receive ICD. Corticosteroids are the mainstay of treatment. Immunotherapy is an effective adjunct that can help taper the glucocorticoids and keep patients in remission. Early introduction of these agents should be considered in these patients. REFERENCE #1: 1. Trivieri MG et al. Challenges in Cardiac and Pulmonary Sarcoidosis: JACC State-of-the-Art Review. J Am Coll Cardiol 2020;76:1878-1901 REFERENCE #2: 2. Nordenswan H-K et al. Outcome of Cardiac Sarcoidosis Presenting With High-Grade Atrioventricular Block. Circulation: Arrhythmia and Electrophysiology 2018;11:e006145 REFERENCE #3: 3. Nagai S, Yokomatsu et al. Treatment with methotrexate and low-dose corticosteroids in sarcoidosis patients with cardiac lesions. Intern Med 2014;53:427-33. DISCLOSURES: No relevant relationships by Roy Chung, source=Web Response No relevant relationships by Sachin Kumar, source=Web Response No relevant relationships by Raunak Nair, source=Web Response

Myocardial Metabolic Response Predicts Chemotherapy Curative Potential on Hodgkin Lymphoma: A Proof-of-Concept Study.

Genome sharing between cancer and normal tissues might imply a similar susceptibility to chemotherapy toxicity. The present study aimed to investigate whether curative potential of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) is predicted by the metabolic response of normal tissues in patients with Hodgkin lymphoma (HL). METHODS: According to current guidelines, 86 patients with advanced-stage (IIB-IVB) HL, prospectively enrolled in the HD0607 trial (NCT00795613), underwent 18 F-fluorodeoyglucose PET/CT imaging at diagnosis and, at interim, after two ABVD courses, to decide regimen maintenance or its escalation. In both scans, myocardial FDG uptake was binarized according to its median value. Death and disease relapse were recorded to estimate progression-free survival (PFS) during a follow-up with median duration of 43.8 months (range 6.97–60). RESULTS: Four patients (4.6%) died, while six experienced disease relapse (7%). Complete switch-off of cancer lesions and cardiac lighting predicted a favorable outcome at Kaplan–Mayer analyses. The independent nature and additive predictive value of their risk prediction were confirmed by the multivariate Cox regression analysis. CONCLUSION: Susceptibility of HL lesions to chemotherapy is at least partially determined by factors featuring the host who developed it.

Non-alcoholic fatty liver disease with reduced myocardial FDG uptake is associated with coronary atherosclerosis

BackgroundNon-alcoholic fatty liver disease (NAFLD) has a significant role in the development of coronary atherosclerosis, independent of traditional cardiovascular and metabolic risk factors. However, the role of myocardial glucose uptake in NAFLD patients who develop coronary atherosclerosis was unclear. The aim of the present study thus was to investigate the association between NAFLD with characteristic of coronary atherosclerotic plaque and myocardial glucose uptake measured by using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Methods and ResultsA total of 418 consecutive subjects who had undergone FDG PET/computed tomography (CT) and coronary computed tomography angiography (CCTA) were retrospectively investigated. Fatty liver was assessed by unenhanced CT. Coronary atherosclerotic plaques and stenosis on CCTA were evaluated. The metabolic parameters were measured on PET images. The ratio of the maximum myocardium FDG value to the mean standardized uptake value of liver (SUVratio) was calculated to estimate myocardial glucose uptake. The association of myocardial glucose uptake with NAFLD and coronary atherosclerosis was determined by multivariate logistic regression analysis. The proportion of low SUVratio in patients with NAFLD was significantly higher compared to those without NAFLD (45.00% vs 19.82%, P < .001). There was a significantly negative correlation between myocardial FDG uptake and hepatic steatosis in association trend analysis (P < .001). When the proportion of individuals with non-calcified plaque on CCTA is stratified by quartiles of SUVratio, patients with low quartiles of SUVratio were more likely to have higher proportion of non-calcified plaque than those with high quartiles of SUVratio (Q1 and Q2 vs Q3 and Q4, P = .003). The trend analysis presented correlated inversely relationship between non-calcified plaque and myocardial SUVratio (P = .001). Moreover, multivariate regression analysis showed that the low SUVratio was independently associated with NAFLD, non-calcified plaque, and significant stenosis after adjusting for clinically important factors. ConclusionWe demonstrated that the presence of reduced myocardial glucose uptake in patients with NAFLD was independently associated with non-calcified plaque and significant stenosis, suggesting an increased risk of coronary atherosclerosis and future cardiovascular events.

Myocarditis as a Manifestation of a T Cell Lymphoproliferative Disorder in a Patient Undergoing Left Ventricular Assistance Device Implantation

<h3>Introduction</h3> Left ventricular assist device (LVAD) core pathology may provide definitive cardiomyopathy etiology and guide management. We present a case of progressive cardiomyopathy concerning for myocarditis in a patient with cutaneous T cell lymphoma (CTCL) undergoing LVAD implantation. <h3>Case Report</h3> A 63-year-old man presented with mildly reduced left ventricular ejection fraction (LVEF) and ventricular tachycardia (VT). He had an extensive history of Gulf War Syndrome, heavy metal exposure, chronic kidney disease, hypercalcemia and cutaneous T cell lymphoma, managed with ultraviolet light therapy and methotrexate. Cardiac magnetic resonance (CMR) imaging demonstrated anteroseptal and inferolateral wall delayed gadolinium enhancement (DGE). Coronary angiography showed no coronary artery disease. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed reduced lateral and inferior wall perfusion but no myocardial FDG uptake or evidence of systemic CTCL. Endomyocardial biopsy demonstrated mild hypertrophy and marked interstitial fibrosis, however no evidence of sarcoidosis or myocarditis. Over the next 2 years, his cardiomyopathy progressed (LVEF 15-20%, LVDd 7.2cm). Upon readmission for VT and heart failure (HF), repeat FDG-PET showed myocardial FDG uptake - perfusion mismatch pattern prompting oral prednisone initiation. Durable LVAD was implanted 5 days later given clinical progression. LVAD core pathology showed myocardial T cell infiltration with a clonal T cell gene rearrangement (Figure 1). Peripheral blood and PET markers remained otherwise negative for CTCL. After LVAD, his HF and VT stabilized, and he is undergoing treatment plan for systemic T cell lymphoproliferative disorder. <h3>Summary</h3> We present a case of myocardial T cell lymphoproliferative disorder presenting as progressive cardiomyopathy and highlight the role of LVAD core pathology in diagnosis.

Pre-Treatment Myocardial 18FDG Uptake Predicts Response to Immunosuppression in Patients With Cardiac Sarcoidosis

ObjectivesThis study identified predictors of clinical (CR) and echocardiographic response (ER) following immunosuppressive therapy (IST) in patients with cardiac sarcoidosis (CS). BackgroundIST has been the cornerstone of treatment for patients with CS and active myocardial inflammation. However, there are little data to explain the variable response to IST in CS. MethodsData of 96 consecutive patients with CS from the Granulomatous Myocarditis Registry were analyzed. All patients underwent a 18fluorodeoxy glucose positron emission tomography−computed tomography (18FDG-PET-CT) before initiation of IST. Response was assessed after 4 to 6 months of therapy. CR was defined as an improvement in functional class (New York Heart Association functional class ≥I) and freedom from ventricular arrhythmias and heart failure hospitalizations. ER was defined as an improvement in left ventricular ejection fraction (LVEF) ≥10%. ER was assessed only in patients with a LVEF <50%. Complete responders had no residual myocardial FDG uptake and fulfilled both response criteria. Partial responders fulfilled only 1 response criteria or had residual FDG uptake. Nonresponders did not fulfill either CR or ER criteria. The uptake index (UI) was defined as the product of maximum standardized uptake value and the number of LV segments with abnormal uptake on 18FDG-PET-CT. ResultsAmong 91 patients included in the final analysis, 54.9%, 20.9%, and 24.2% of patients were classified as complete and partial responders and nonresponders, respectively. Cox regression analysis (all responders vs. nonresponders) identified the following as independent predictors of response following immunosuppression: LVEF >40% (hazard ratio: 1.61; 95% confidence interval: 1.06 to 7.69; p = 0.031) and myocardial UI >30 (hazard ratio: 1.28; 95% confidence interval: 1.05 to 6.12; p = 0.010). The final model had a good discriminative power (area under the curve [AUC]: 0.85) and predictive accuracy (sensitivity: 85.5%; specificity: 86.4%). Pre-treatment myocardial UI had a strong positive correlation with change in LVEF following immunosuppression. ConclusionsPre-treatment 18FDG myocardial uptake was a predictor of CR and ER response to immunosuppression in patients with CS.

Associations of physiologic myocardial 18F-FDG uptake with fasting duration, HbA1c, and regular exercise.

The variability of physiologic 18F-FDG uptake in the myocardium has hampered the accurate evaluation of cardiac glucose metabolism. We investigated the effects of multiple factors, including fasting duration and physical activity, on the physiologic uptake of 18F-FDG by the myocardium in healthy participants. A total of 446 participants (predominantly male, 91%) in a health screening program were included in this retrospective study. For the visual analysis of myocardial 18F-FDG uptake, the participants were categorized into three groups according to qualitative visual scales (QVS). For the quantitative analysis, the maximum SUV of the left ventricular myocardium was measured. Significant differences were observed in fasting duration (p < 0.001), SUVmax (p < 0.001), aspartate aminotransferase (AST) (p < 0.001), alanine aminotransferase (ALT) (p < 0.001), gamma-glutamyl transpeptidase (γ-GTP) (p = 0.001), and uric acid (p = 0.015) among the QVS groups. Participants who regularly exercised with vigorous activity (p = 0.032) and HbA1c > 6% (p = 0.005) showed significant association with myocardial FDG uptake in the Chi-squared test. The median value of fasting duration decreased significantly as the QVS of the myocardium increased. Twenty-nine of the 31 participants (93.5%) who fasted for 21.5h or more showed a suppressed FDG uptake (mean SUVmax = 2.1). In multivariate logistic regression analysis, fasting duration (OR = 0.74, 95% CI 0.69-0.80, p < 0.001), HbA1c > 6% (OR = 0.29, 95% CI: 0.12 - 0.66, p = 0.004), uric acid (OR = 0.82, 95% CI 0.68-1.00, p = 0.049) and regular exercise with vigorous activity (OR = 1.75, 95% CI 1.13-2.70, p = 0.012) were significant factors for physiologic myocardial FDG uptake. Reduced physiologic 18F-FDG uptake of the myocardium was associated with longer fasting duration, higher level of HbA1c, and less frequency of regular exercise with vigorous activity. For the preparation of cardiac 18F-FDG PET, inclusion of longer fasting duration (more than 18h) might be necessary for the adequate suppression of physiologic 18F-FDG myocardial uptake.

Association between FDG uptake in the right ventricular myocardium and cancer therapy-induced cardiotoxicity

BackgroundThe aim of this study was to investigate changes in myocardial uptake evaluated by oncologic 18F-fluorodeoxyglucose (FDG) PET/CT scans and to determine the relationship between myocardial FDG uptake and cancer therapy-induced cardiotoxicity in breast cancer patients who underwent anthracycline or trastuzumab. MethodsWe reviewed 121 consecutive patients who underwent oncologic FDG PET/CT and echocardiography at baseline and post-therapy with anthracyclines or trastuzumab for breast cancer. Grade in LV wall, uptake pattern in LV wall, and the presence of RV wall uptake were assessed by visual analysis, and the mean SUV in the LV and RV walls and the change of SUV (ΔSUV) between baseline and post-therapy PET/CT were measured by quantitative analysis. Multiple logistic regression analyses were performed to evaluate the association between PET parameters and cardiotoxicity. ResultsFifteen patients (12%) showed cardiotoxicity after therapy. The cardiotoxic group tended to show more diffuse LV uptake, higher SUV, and ΔSUV of RV wall than the non-cardiotoxic group following therapy with anthracyclines or trastuzumab. Logistic regression analysis showed that the presence of RV wall uptake, SUV of RV wall (> 1.8), and ΔSUV of RV wall (> 0.4) were significantly associated with cardiotoxicity after controlling for age, radiotherapy, and treatment. ConclusionsThe presence of RV wall uptake and the increase of SUV of RV wall on post-therapy PET/CT were associated with cardiotoxicity in breast cancer patients who underwent anthracycline or trastuzumab. Oncologic FDG PET/CT scans can provide information regarding cancer therapy-induced cardiotoxicity as well as tumor response.

Prevalence of newly diagnosed sarcoidosis in patients with ventricular arrhythmias: a cardiac magnetic resonance and 18F-FDG cardiac PET study.

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE.

Cardiac sarcoidosis: frequency, diagnostic approach and follow-up in a tertiary center

Abstract Background Cardiac sarcoidosis (CS) is associated with poor prognosis, making early diagnosis and treatment important. The aim of this study is to evaluate our diagnostic results and follow-up for the diagnosis of CS in a tertiary center. Methods We studied 188 patients with proven extra-cardiac sarcoidosis referred to our outpatient clinic for evaluation of cardiac involvement. Eight patients were excluded because electrocardiogram (ECG) and/or transthoracic echocardiography (TTE) was missing. Cardiac magnetic resonance (CMR) and/or positron emission tomography (PET) was performed in 66% and 37% of the patients, respectively. Median follow-up duration was 2.9 [1.2–5.3] years. The diagnosis of CS was based on the Heart Rhythm Society criteria. Results Cardiac symptoms defined as palpitations, angina, dyspnea and (near)-syncope were present in 156 of 180 (87%) patients. Any abnormality on ECG (bundle branch blocks, atrioventricular blocks, sinus tachycardia or atrial fibrillation) and/or TTE (left ventricular ejection fraction &amp;lt;55%, presence of regional wall abnormalities or myocardial hypertrophy) was found in 92/180 (51%) patients. CS was diagnosed in 42 of 180 (23%) patients, of whom 31 (74%) had any ECG and/or TTE abnormalities. However, ECG and/or TTE abnormalities were also present in 44% of the patients without cardiac involvement. Patients with CS showed a second type II or third degree AV-blocks in 3/42 (7%), a left ventricular ejection fraction &amp;lt;35% on TTE in 9/42 (21%), late gadolinium enhancement by CMR consistent with CS in 28/34 (82%), and myocardial FDG uptake by PET in 19/31 (61%). In 84 of the 138 patients without cardiac involvement, CMR was performed. In 15 patients an alternative diagnosis was found (i.e. myocardial infarction or other non-ischemic cardiomyopathy). The estimated 8-year cumulative event rate composite endpoint of sustained ventricular tachycardia, ventricular fibrillation, aborted sudden cardiac death, heart transplantation and all-cause mortality was 41% in the CS patients and 12% in the patients without CS (Figure 1, p&amp;lt;0.001). Conclusions In our study, 23% of the patients with proven extra-cardiac sarcoidosis was diagnosed with CS. Cardiac symptoms, ECG and TTE were of limited diagnostic value for screening for CS. CMR provided a good diagnostic yield and identified other cardiac diseases in a substantial number of patients. Figure 1. KMCurve_CompositeEndpoint Funding Acknowledgement Type of funding source: None

Ventricular tachycardia in cardiac sarcoidosis -prognosis, characterization of ventricular substrates and outcomes of treatment-

Abstract Background The prognosis, the underlying substrate and clinical outcomes of treatment are unclear in patients with cardiac sarcoidosis (CS)-related ventricular tachycardia (VT). Objective This study investigated the prognosis and the relationship between electroanatomical mapping (EAM) and imaging findings in patients with CS-related VT. Methods A total of 203 CS patients (Age 68.1±11.6 years, 87 males) were enrolled at two tertiary care medical centers between 2000 and 2018. All met the 2016 Japanese Circulation Society guidelines for diagnosis of CS. They were followed for a composite of major adverse cardiac events (MACE) including cardiac death, heart transplantation, unscheduled hospitalization for heart failure, and life-threatening ventricular arrhythmias. Distribution of late gadolinium enhancement (LGE) on cardiac MRI (CMR) and/or an abnormal myocardial 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography at diagnosis were examined. The relationship between EAM and the image findings were also analyzed in patients with radiofrequency ablation (RFA) for VT. Results During a median follow-up of 53 months, 87 of the 203 patients (43%) experienced a MACE. Baseline factors associated with MACE were presence of sustained VT (HR, 2.43, 95% CI 1.54–3.85, P&amp;lt;0.001), left ventricular ejection fraction below 50% (HR, 1.95 95% CI 1.07–3.56, P=0.029), and abnormal myocardial FDG uptake (HR, 2.42 95% CI 1.04–5.61, P=0.039). Overall, 69 of the 203 patients (34%) experienced sustained VT. Abnormal myocardial FDG uptake was significantly more prevalent in patients with VT than in those without (92.7% vs. 78.5%, P=0.02). A total of 25 patients (9.9%) required RFA for CS-related VT (Age 64.0±8.7 years, 12 males, 1.32±0.56 RFAs per patient). Abnormal electrocardiograms (EGM) were observed in 22 of the 25 patients (88%). LGE was more frequent than abnormal FDG uptake in areas with an abnormal EGM (77% vs. 41%; P=0.002). Over a mean follow-up period of 67-months, 13 of the 25 patients with RFA (52%) remained free of VT episodes (Figure). VT recurred in nine of the 12 patients with RFA and in 17 of the 47 patients without RFA, but was suppressed by intensive pharmacologic therapy such as the combined use of amiodarone and sotalol. In patients with CS-related VT, survival without experiencing a MACE did not differ in participants with or without RFA. Conclusions In our 203 CS patients, sustained VT and abnormal FDG uptake were associated with worse cardiac outcomes. The prevalence of abnormal FDG uptake was significantly higher in patients with CS-related VT, LGE on CMR was more frequent within localized areas of an abnormal EGM, suggesting that both scar itself and the associated inflammation were involved in the pathogenesis of CS-related VT. Successful RFA of CS-related VT is still challenging, and recurrence is common. Preprocedural CMR can be useful in detecting abnormal EGMs that are potential targets for substrate ablation. Funding Acknowledgement Type of funding source: None

Hybrid CMR- and FDG-PET-imaging gives new insights into the relationship of myocardial metabolic activity and fibrosis in patients with Becker muscular dystrophy

Abstract Background Cardiac involvement in patients with Becker muscular dystrophy (BMD) is an important predictor of mortality. The cardiac phenotype of BMD patients is characterized by slowly progressive myocardial fibrosis that starts in the left ventricular (LV) free wall segments and extends into the septal wall during the disease course. Purpose Since the reason for this characteristic cardiac phenotype is unknown and comprehensive approaches using e.g. hybrid imaging combining cardiovascular magnetic resonance (CMR) with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) are limited, the present study addressed this issue by a comprehensive non-invasive imaging approach. Methods Hybrid CMR- and FDG-PET-imaging was performed in N=14 patients with BMD on a whole-body Biograph mMR system. The CMR protocol comprised cine- and late-gadolinium-enhancement (LGE)-imaging. Metabolism was assessed with FDG-PET after oral glucose loading to effect myocardial carbohydrate uptake. PET was acquired for 65 minutes starting with tracer injection. Uptake values from 60 to 65 minutes p.i. were divided by the area under the blood activity curve and reported as percentages relative to the segment with maximal myocardial FDG uptake. Results In the total study group, mean left ventricular (LV) ejection fraction (EF) was 55±5% and there were 6/14 patients with a reduced LV-EF &amp;lt;55%. A characteristic pattern of LGE in LV lateral wall was observed in 13/14 patients whereas an additional septal LGE pattern was documented in 6/14 patients only. Segmental FDG uptake was 88±6% in the LV lateral wall vs. 77±10% in the septal wall (p&amp;lt;0.001). There was a rather inverse relationship between segmental FDG activity compared to segmental LGE extent (r=−0.33, p=0.089). There were N=6 patients (= ΔFDG-high) with a segmental difference in FDG uptake of &amp;gt;15% in the LV lateral wall compared to the septal wall (lateral FDG = 91±3% vs. septal FDG = 69±8%; p&amp;lt;0.001) while the remaining N=8 patients (= ΔFDG-low) showed a segmental difference in FDG uptake of ≤15% (lateral FDG = 85±7% vs. septal FDG = 83±5%; p=0.37). Patients in the ΔFDG-high group showed a similar LV lateral wall vs. septal wall LGE extent of 12±6% vs. 7±15%, respectively, while those patients in the ΔFDG-low group demonstrated a large difference in LV lateral wall vs. septal wall LGE extent of 33±24% vs. 4±6%, respectively. Conclusions Segmental FDG uptake – reflecting myocardial metabolic activity – is in principal higher in the LV free wall of BMD patients – possibly due to a higher segmental work load. However, segmental metabolic activity seems to be dependent on and limited by the respective segmental extent of myocardial fibrosis as depicted by LGE-imaging. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Deutsche Gesellschaft für Kardiologie (DGK)

Hepatic steatosis is associated with abnormal hepatic enzymes, visceral adiposity, altered myocardial glucose uptake measured by 18F-FDG PET/CT

BackgroundNonalcoholic fatty liver disease (NAFLD) is a multisystem disease that affects the liver and a variety of extra-hepatic organ systems. This study aimed to investigate the relationship between hepatic steatosis and glucose metabolism in liver and extra-hepatic tissues and organs.MethodsThe whole body 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) images of 191 asymptomatic tumor screening patients were retrospectively analyzed. Patients with the ratio of spleen/liver CT densities > 1.1 were defined to have NAFLD, and their clinical symptoms, laboratory markers, FDG uptake in a variety of tissues and organs including heart, mediastinal blood pool, liver, spleen, pancreas, and skeletal muscle, as well as abdominal adipose tissue volumes including visceral adipose tissue (VAT) volume and subcutaneous adipose tissue (SAT) volume were compared with those of the non-NAFLD patients and used to analyze the independent correlation factors of NAFLD.ResultsAmong the 191 patients, 33 (17.3%) were NAFLD, and 158 (82.7%) were non-NAFLD. There was no significant correlation between the mean standardized uptake value (SUVmean) and CT density of liver as well as the ratio of spleen/liver CT densities. Hepatic steatosis, but not FDG intake, was more significant in NAFLD patients with abnormal liver function than those with normal liver function. Compared with the non-NAFLD patients, NAFLD patients had significantly reduced myocardial glucose metabolism, but significantly increased mediastinal blood pool, spleen SUVmean and abdominal adipose tissue volumes (including VAT and SAT volumes) (P < 0.05). Multivariate regression analysis showed that elevated serum ALT, increased abdominal VAT volume, and decreased myocardial FDG uptake were independent correlation factors for NAFLD. Further studies showed that hepatic steatosis and myocardial FDG uptake were mildly linearly correlated (r = 0.366 with hepatic CT density and − 0.236 with the ratio of spleen/liver CT densities, P < 0.05).ConclusionsNAFLD is a systemic disease that can lead to the change of glucose metabolism in some extra-hepatic tissues and organs, especially the myocardium.

Clinical implication of myocardial FDG uptake pattern in oncologic PET: retrospective comparison study with stress myocardial perfusion imaging as the reference standard.

The purpose of this study was to determine the clinical implication of the myocardial FDG uptake patterns by comparing with the results of stress myocardial perfusion imaging (MPI) as the reference standard. By reviewing the medical records, 86 pairs of stress MPI and FDG PET/CT of 84 patients who underwent stress MPI and oncologic FDG PET/CT in 1month were included in this study. The patterns of the myocardial FDG uptake were classified into five patterns such as 'low', 'diffuse', 'basal ring', 'focal high', and 'focal defect on diffuse high'. MPI was evaluated using a 5-point scoring model ranging from 0 (normal uptake) to 4 (uptake absent) based on the 17-segment model. The summed stress score of 4 or higher was defined as 'abnormal MPI'. Factors predictive of abnormal MPI were analyzed using a log-rank multivariate test and p < 0.05 was set as significant. Abnormal MPI was observed in only 16 of 36 (44%) patients with 'low' pattern, 10 of 23 (43%) patients with 'diffuse high' pattern, and 1 of 9 (11%) patients with 'basal ring' pattern, but in 8 of 9 (89%) patients with 'focal high' pattern, and 8 of 9 (89%) patients with 'focal defect on diffuse high' pattern. The log-rank multivariate test revealed that 'focal high' and 'focal defect on diffuse high' pattern were correlated with an abnormal MPI. These results indicate that further cardiac work-up might be helpful in the patients with 'focal high' pattern or 'focal defect on diffuse high' pattern of myocardial FDG at oncologic PET. A prospective study should be needed to further support this conclusion.

1050 Normal imaging findings after aortic valve implantation on 18f-fluorodeoxyglucose positron emission tomography with computed tomography and computed tomography angiography

Abstract Purpose Although 18F-Fluorodeoxyglucose (18F-FDG) Positron Emission Tomography (PET) with computed tomography (CT) and cardiac computed tomography angiography (CTA) are essential tools in diagnosing prosthetic heart valve (PHV) endocarditis, the normal imaging findings in the first year after PHV implantation on 18F-FDG-PET/CT and CTA have not been studied prospectively. We prospectively assessed the perivalvular FDG uptake at different time points after aortic PHV implantation and assessed the normal imaging findings on CTA. Materials and methods Patients who had undergone uncomplicated aortic PHV implantation were included and underwent 18F-FDG PET/CT and CTA at 5(±1) weeks (group 1), 12(±2) weeks (group 2) or 52(±8) weeks (group 3) after implantation. After a preparatory diet to suppress normal myocardial glucose uptake, FDG uptake in the myocardium as well as around the PHV was scored using the Qualification Visual Score for Hypermetabolism (QVSH) as "none" (&amp;lt; mediastinum), "low" (&amp;gt; mediastinum but &amp;lt; liver), "intermediate" (&amp;gt; liver), or "high" (intense uptake) and quantitative analysis was performed with maximum Standardized Uptake Value (SUVmax) and target to background ratio (SUVratio) on standardized European Association of Nuclear Medicine Research Ltd. (EARL) reconstructions by an experienced nuclear medicine physician. CTA was analysed for image quality, artefacts and stranding of the peri-aortic fat by a cardiac radiologist. Results In total 37 patients (group 1: n = 12, group 2: n = 12, group 3: n = 13) (age 66 ± 8 years) were included. Myocardial FDG uptake was intermediate or less in 29/37 scans (78%). QVSH around the PHV was 8/12(67%) low and 4/12(33%) intermediate in group 1, 7/12(58%) low and 5/12(42%) intermediate in group 2 and 8/13(62%) low and 5/13(38%) intermediate in group 3 (p = 0.91). No scan was scored as "none" or "high". EARL SUVmax was 3.48 ± 0.57, 3.50 ± 0.59 and 3.34 ± 0.55 (mean ± SD, p = 0.77) and EARL SUVratio was 2.00 ± 0.29, 1.96 ± 0.41 and 1.71 ± 0.26 (mean ± SD, p = 0.07) for groups 1, 2 and 3, respectively. One patient in group 3 refused to undergo the additional CTA and one CTA in group 3 could not be analysed for image quality and artefacts due to techniqual difficulties. Overall CTA image quality was "good" or "excellent" with an artefact score of "virtually none" or "mild" in most cases (n = 33, 94%). Stranding of peri-aortic fat was seen in 27/35 (77%) of these patients (group 1: n = 11; group 2: n = 9; group 3: n = 7) with no signs of FDG uptake on PET/CT scan. Conclusion Baseline FDG uptake around aortic PHV at 5, 12 and 52 weeks after implantation is similar and mild in the majority of cases with an overall mean SUVmax and SUVratio of 3.44 ± 0.56 and 1.89 ± 0.34 respectively. CTA revealed baseline post-surgical findings in the first year after PHV implantation.

Role of FDG-PET/CT in Assessing the Correlation Between Blood Pressure and Myocardial Metabolic Uptake.

Objective(s):We aimed to assess the association between blood pressure and LV myocardial uptake of FDG, hypothesizing that subjects with raised blood pressure would have higher FDG uptake.Methods:We analyzed 86 healthy controls who underwent PET/CT imaging 180 minutes following FDG (4 MBq/Kg) administration. LV myocardial analysis was performed on axial sections using standard operator guided computer software (OsiriX MD). The average LV myocardial SUVmean (MSUVmean) was calculated for each subject. Subjects were assessed according to the 2017 ACC/AHA guidelines for high blood pressure in adults. Mean arterial blood pressure (MABP) was calculated for each patient. Regression models were employed for statistical analysis. Results:The association of MSUVmean was more pronounced with DP (r=0.32, p=0.003) than SP (r=0.28, p=0.010); MABP was comparable (r=0.33, p=0.002). Correlations of MSUVmean with categorized BPs were: normal SP (r=0.27, p=0.010), elevated SP (r=0.28, p=0.009), stage 1 SP (r=0.27, p=0.010), stage 2 SP (r=0.28, p=0.008); normal DP (r=0.33, p=0.001), stage 1 DP (r=0.34, p=0.001), stage 2 DP (r=0.35, p=0.001). Multivariate analysis demonstrated DP (p=0.006), MABP (p=0.007), and SP (0.026).Conclusion:LV myocardial FDG uptake was higher in subjects with elevated blood pressure and correlated positively with SBP and in particular DBP and MABP.

Myocardial Positron Emission Tomography for Evaluation of Cardiac Sarcoidosis: Specialized Protocols for Better Diagnosis.

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology with various clinical presentations depending on the organs involved. Since cardiac sarcoidosis (CS) portends a higher risk of morbidity and mortality, early diagnosis and aggressive medical treatment are essential to improve the prognosis. 18F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) has emerged as an important tool with practical advantages in assessing disease activity and monitoring the treatment response in patients with CS. While it has high sensitivity, it also has great variability in specificity, probably due to normal physiologic myocardial FDG uptake, which interferes with the evaluation and follow-up of CS using FDG-PET. This review details the technical aspects of FDG-PET imaging for evaluating and diagnosing CS, assessing disease activity, and monitoring therapeutic response.

Simultaneous determination of dynamic cardiac metabolism and function using PET/MRI

BackgroundCardiac metabolic changes in heart disease precede overt contractile dysfunction. However, metabolism and function are not typically assessed together in clinical practice. The purpose of this study was to develop a cardiac positron emission tomography/magnetic resonance (PET/MR) stress test to assess the dynamic relationship between contractile function and metabolism in a preclinical model. MethodsFollowing an overnight fast, healthy pigs (45-50 kg) were anesthetized and mechanically ventilated. 18F-fluorodeoxyglucose (18F-FDG) solution was administered intravenously at a constant rate of 0.01 mL/s for 60 minutes. A cardiac PET/MR stress test was performed using normoxic gas (FIO2 = .209) and hypoxic gas (FIO2 = .12). Simultaneous cardiac imaging was performed on an integrated 3T PET/MR scanner. ResultsHypoxic stress induced a significant increase in heart rate, cardiac output, left ventricular (LV) ejection fraction (EF), and peak torsion. There was a significant decline in arterial SpO2, LV end-diastolic and end-systolic volumes in hypoxia. Increased LV systolic function was coupled with an increase in myocardial FDG uptake (Ki) during hypoxic stress. ConclusionPET/MR with continuous FDG infusion captures dynamic changes in both cardiac metabolism and contractile function. This technique warrants evaluation in human cardiac disease for assessment of subtle functional and metabolic abnormalities.