AIM:Aortic root (AoR) dilatation is a condition that requires monitoring of its growth through serial imaging studies in order to determine appropriate treatment. Systematic differences in AoR measurements have been reported between transthoracic echocardiography (TTE) and cross-sectional imaging techniques. The aim of this study was to determine which AoR measurement-performed using cardiac computed tomography angiography (CCTA) in patients with tricuspid aortic valves-shows the best correlation with the standard measurement obtained by TTE. MATERIAL AND METHODS:A retrospective analysis was conducted on 110 patients who underwent both CCTA and TTE within a six-month interval at our institution, including an equal number of patients with and without AoR dilatation. On the transverse plane of the AoR in CCTA, the following measurements were taken: cusp-to-commissure, cusp-to-cusp, area, area-derived diameter (ADD) and anteroposterior diameter (APD). CCTA measurements showed excellent correlation with TTE (p < 0.001), with the highest degree of agreement observed for ADD and APD (both p < 0.001). RESULTS:APD measurements did not differ significantly from those obtained by TTE in any group (overall p = 0.451; non-dilated AoR p = 0.427; dilated AoR p = 0.091), in contrast to the other measurements, including ADD. CONCLUSION:The APD measurement obtained by CCTA proved to be equivalent to that obtained by TTE, easy to perform and highly reproducible. Future research may establish APD as the reference measurement for comparing results between both techniques.

Antecedentes y objetivo La dilatación de la raíz aórtica (RaAo) es una condición que requiere monitorizar su crecimiento mediante estudios de imagen seriados a fin de definir el tratamiento. Se han reportado diferencias sistemáticas en las medidas de la RaAo entre la ecocardiografía transtorácica (ETT) y las técnicas seccionales. El objetivo de este estudio fue definir qué medición de la RaAo en válvulas aórticas tricúspides evaluada mediante angiotomografía computarizada cardíaca (ATCC) presentaba mejor correlación con la medición estándar por ETT. Material y métodos Se realizó un análisis retrospectivo de 110 pacientes que se sometieron a ATCC y ETT en un intervalo menor a 6 meses en nuestra institución, incluyendo de forma equilibrada pacientes con y sin dilatación de la RaAo. En el plano transversal de la RaAo en la ATCC se midieron distancias cúspide-comisura, cúspide-cúspide, el área y el diámetro derivado del área (DDA), así como la distancia anteroposterior (DAP). Las mediciones por ATCC mostraron excelente correlación con ETT (p<0,001), destacando el mejor grado de concordancia con el DDA y la DAP (ambos p<0,001). Resultados Las mediciones de DAP no difirieron significativamente de las obtenidas por ETT en ningún grupo (global p=0,451; RaAo no dilatada p=0,427; RaAo dilatada p=0,091), a diferencia del resto de mediciones, incluido el DDA. Conclusión La medición DAP mediante ATCC resultó equivalente a la obtenida por ETT, fácil de obtener y altamente reproducible. Investigaciones futuras podrían confirmar el DAP como la medida de referencia para comparar resultados entre ambas técnicas.

Abstract Background [18F]FDG PET/CTA has significantly improved the diagnostic yield of prosthetic valve endocarditis. The concern about differentiating infection from inflammation has been progressively overcome in surgical prosthetic valve replacement, but could still pose a challenge and has not been well evaluated in TAVI patients due to the little available data on the morphologic and metabolic features following TAVI. Purpose To find out the morpho-metabolic features of non-infected TAVI (NI-TAVI) and their evolution over time and compare them with a group of patients with suspected TAVI infective endocarditis (TAVI-IE), to determine imaging criteria to help differentiate between TAVI infection and non-infection by [18F]FDG PET/CTA. Methods We prospectively recruited 31 patients in the control group with TAVI implantation for severe aortic stenosis between September 2021 and October 2022. They underwent seriated PET/CTA scans at 1, 6 and 12 months after valve implantation. We evaluated the metabolic features (visual and quantitative FDG uptake) and anatomic changes following valve implantation, and their temporal evolution. We compared these "normal" features with the PET/CT findings in a group of 35 patients with definite TAVI-IE. Results Thirty-one patients (22 men, average 80 years old) were scanned at 1 month after implantation, of whom 29 and 25 were re-scanned at 6 and 12 months, respectively (3 deaths, 3 not performed due to severe patient´s complications). FDG uptake was visually detectable in 18/31 (58%), 15/29 (52%) and 9/25 (36%) of NI-TAVI at 1, 6 and 12 months after implantation, respectively. Uptake showed a diffuse and homogeneous distribution pattern in 83%. Quantitative analysis showed no significant differences and stability of the FDG uptake values (SUVmax, SUVmean and SUVratio) at 1, 6 and 12 months. VUI values were also stable and far below the cut-off value for infection reported in surgically implanted PV among the 3 scan periods. No anatomic changes or lesions suggesting endocarditis were detected in any patient of the control group at the first scan or during follow-up (2 cases showed subclinical leaflet thrombus deposit). Within the suspected TAVI-IE group (n=35) there were 19 definitive IE and 16 rejected or possible. Quantitative values in comparison with the NI-TAVI group are described in the results table. FDG uptake pattern was focal or heterogenous in 70%, and regarding anatomic lesions, we found vegetations in 8 patients, abscess in 3 and one pseudoaneurysm in the definitive group. (Results Table). Conclusion FDG uptake was visually detected in >50% of the NI-TAVI group, displaying a diffuse-homogenous pattern in most cases, and a normal VUI, findings present in the immediate postoperative period and stable after 1 year. The TAVI-IE group showed higher SUV values in definitive IE, focal or heterogeneous uptake pattern in most cases, higher VUI and more frequently associated anatomical lesions.

Abstract Background In systemic sclerosis (SSc) primary heart involvement, although not exhaustively studied, is frequent and may have prognostic consequences. Purpose This pilot cohort study reports a descriptive analysis of patients’ evaluation in a Nuclear Cardiology Unit. Methods Prospective study. Between 2012 and 2016, 62 patients (age 56.8 ± 12.9 years, men 12.9%) with SSc referred from the Autoimmune Systemic Diseases Unit for cardiac evaluation were prospectively analyzed. All patients were studied with gated Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (gSPECT-MPI) during rest, exercise and cold test. Ventricular synchrony was assessed by Emory Cardiac ToolboxTM program, and coronary anatomy was evaluated by coronary computed tomography angiography (CCTA) in all patients. Statistical analyses were performed using STATA 18. StataCorp, College Station, TX, USA. Results Most patients were women (86.9%). The prevalence of arterial hypertension (55.7%) and hypercholesterolemia (39.3%) was high, in contrast, the prevalence of diabetes mellitus (4.9%), tobacco (8.2%) and chronic renal failure (3.2%) was low. The prevalence of angina (19.4%), dyspnea (35.5%) and the clinical history of cardiac event (myocardial infarction [n=5], heart failure [n=2], unstable angina [n=4], coronary revascularization [n=1], pericardial diseases [n=2], syncope [n=1]) was high (19.3%). A quarter of the patients had pulmonary arterial hypertension. Electrical conduction disorder was observed in 27.4% of patients (left bundle branch block, right bundle branch block, and left anterior hemiblock), and no patient had a pacemaker. Myocardial ischemia (MIs) (Summed Difference Score ≥ 2) was observed in 24.2% of patients who underwent SPECT exercise-rest and in 22.6% of patients who underwent SPECT cold-rest test. Five percent of patients without MIs in the SPECT cold-rest test presented MIs in the SPECT exercise-rest test, and 8.5% of patients without MIs in the SPECT exercise-rest test had it in the SPECT cold-rest test. The overall agreement for MIs tests was 85.5%. Left ventricular ejection fraction <50% was observed in 12% of patients. Ventricular dyssynchrony (BD > 51º) was observed in 64.5% of patients. A calcium score > 100 AU and a calcium score ≥ 400 AU was observed in 33.9% and 11.5% of patients, respectively. Coronary artery disease was detected in 29% of patients, of which 44% presented significant coronary stenosis (≥ 50%). Conclusion This pilot and descriptive study reveals that patients with SSc have cardiac involvement in a non-negligible percentage of the cases and may benefit of a comprehensive evaluation using Nuclear Cardiology techniques among others tests.

Abstract Background It is widely acknowledged that patients with systemic sclerosis (SSc) experience elevated rates of cardiovascular mortality and morbidity over the course of their lives. Purpose The aim of this exploratory pilot study is to examine the prognostic variables for all-cause mortality detected in patients with SSc detected by nuclear imaging and cardiac CT. Methods Prospective cohort study. During a period of 4 years (2012 to 2016), 62 (age 56.8 ± 12.9 years, men 12.9%) patients with SSc referred from the Medicine Service for a cardiological evaluation. These patients underwent gated Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (gSPECT-MPI) stress-rest and also underwent coronary computed tomography angiography (CCTA). Cox regression analysis (STATA 18, StataCorp, College Station, TX, USA) was employed for statistical analyses to evaluate independent predictive variables, with adjustments made for age and gender. Results During a long follow-up of 7.6 ± 2.3 years post gSPECT and CCTA, 12 deaths (9 non-cardiac deaths and 3 cardiac deaths) (0.025 exitus/patients/years) was observed. In the univariate Cox regression analysis, previous cardiac event (myocardial infarction, heart failure, unstable angina, coronary revascularization, syncope) (HR: 6.1, p=0.005), coronary artery disease (stenosis > 10%) (HR:8.2, p=0.003), significant coronary artery disease (CAD) ≥ 50% (HR: 3.9, p=0.036), calcium score ≥ 200 AU (HR: 3.2, p=0.045), METs ≤ 5 (HR: 5.3, p=0.007), cold test resistance ≤ 1 minute (HR: 10, p=0.027), summed thickening score at rest (HR: 1.12, p=0.016) and diastolic dysfunction (TPFR: Time to Peak Filling Rate > 250 mseg) (HR: 4.9, p=0.010), were significant. All these variables were used for multivariate Cox analysis, and the final predictive model for all-cause mortality adjusted by age and gender (Harrell’s = 0.905, Somers’ D = 0.809) was (Results Table): Conclusion In this pilot cohort study with long follow-up in patients with SSc a significant CAD, the exercise capacity, the cold test resistance and the diastolic disfunction emerged as the most crucial variables in predicting all-cause mortality, demonstrating good accuracy.

The microbiology, epidemiology, diagnostics, and treatment of infective endocarditis (IE) have changed significantly since the Duke Criteria were published in 1994 and modified in 2000. The International Society for Cardiovascular Infectious Diseases (ISCVID) convened a multidisciplinary Working Group to update the diagnostic criteria for IE. The resulting 2023 Duke-ISCVID IE Criteria propose significant changes, including new microbiology diagnostics (enzyme immunoassay for Bartonella species, PCR, amplicon/metagenomic sequencing, in situ hybridization), imaging ([18F]FDG PET/CT, Cardiac Computed Tomography), and inclusion of intraoperative inspection as a new Major Clinical Criterion. The list of "typical" microorganisms causing IE was expanded and includes pathogens to be considered as typical only in the presence of intracardiac prostheses. The requirements for timing and separate venipunctures for blood cultures were removed. Last, additional predisposing conditions (transcatheter valve implants, endovascular cardiac implantable electronic devices, prior IE) were clarified. These diagnostic criteria should be updated periodically by making the ISCVID-Duke Criteria available online as a "Living Document".

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Commission in the H2020 program: Project SMARTool, “Simulation Modeling of coronary ARTery disease: a tool for clinical decision support—SMARTool” Background and aims The coexistence of elevated plasma triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C) may contribute to the residual cardiometabolic risk of coronary artery disease (CAD) independently of total cholesterol and low-density lipoprotein cholesterol (LDL-C) absolute plasma levels [1]. Aim of this study is to assess whether a high TG/HDL-C ratio is characterized by a specific lipidomics signature in statin users and its relationship with the coronary risk score defined by coronary computed tomography angiography (CTA). Methods TG/HDL-C ratio was calculated in 132 patients (68.8±7.7 years, 85 males) with suspected or known CAD referred to coronary CTA and receiving statins treatment in the last 6.3 ± 1.4 years before enrolment. Patients were grouped according to TG/HDL-C ratio quartiles: IQ (≤1.694), IIQ (1.695-2.399), IIIQ (2.400-3.281), and IVQ (>3.282). Coronary CTA exams were analysed according to the modified 17-segment American Heart Association classification [2] and interpretable segments were visually assessed for degree of stenosis and plaque composition. A comprehensive coronary risk score (CTA score) [3], previously validated as predictor of adverse outcome, was calculated in each patient. Except for subjects with normal arteries (CTA score = 0), all patients were classified into 3 groups of CTA score severity: low (score < 5), intermediate (score 5-20) and high (score > 20) risk [4]. Patient-specific plasma targeted lipidomics was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This approach allowed to quantify 69 circulating lipids encompassing six lipid classes (triacylglycerol [TG], phosphatidylcholine [PC], phosphatidylethanolamine [PE], ceramide [Cer], sphingomyelin [SM], cholesterol ester [CE]). Differential analysis was performed using TG/HDL-C and CTA score annotation. Results 18 altered lipid species in the group with higher TG/HDL-C ratio were also altered in the group with higher CTA risk score. This common set of lipids is composed of CE(16:0), CE(18:0), PC(38:2), 8 SM [SM(34:2), SM(38:2), SM(41:2), SM(41:1), SM(42:4), SM(42:3), SM(42:1), SM(43:3)], TG(52:1) and 6 PE [PE(34:0), PE(34:1), PE(34:2), PE(36:1), PE(36:2), PE(36:3)], and represents the lipidomics signature associating elevated plasma TG/HDL-C ratio with high CTA risk score in statin users. Conclusion In patients with stable CAD under statin treatment, a specific pattern of altered lipids, characterized by reduced plasma levels of cholesterol esters and sphingomyelins and increased levels of triacylglicerols and phosphatidylethanolamines, is associated with high TG/HDL-C ratio and high CTA score. This specific lipidomic signature identifies patients with higher residual cardiometabolic and coronary risk, not tackled by current lipid lowering therapy, unveiling possible new molecular targets of treatment.

Valorar la relación entre el score de calcio coronario y la elección posterior del kilovoltaje según el criterio del radiólogo en un protocolo estándar (PE) de angio-TC coronaria (aTCC) para descartar enfermedad coronaria. Cuantificar la reducción de la radiación ionizante después de vincular el kilovoltaje al índice de masa corporal en un protocolo de baja dosis (PBD) con reconstrucción iterativa de modelado. Valorar la calidad de imagen y el rendimiento diagnóstico del PBD. Las características antropométricas, el score de calcio, los niveles de kilovoltaje y los valores de dosis estimada específica para el tamaño (SSDE) y del producto dosis-longitud fueron comparados entre un grupo de 50 pacientes con PBD reclutados prospectivamente y una cohorte histórica adquirida con el PE. Estos parámetros, el número de segmentos coronarios no valorables sin y con tolerancia de fase, la atenuación y la relación señal-ruido en la aorta ascendente en el PBD fueron correlacionados con una calidad de imagen de nivel excelente según una escala semicuantitativa. El rendimiento diagnóstico por paciente fue calculado usando la revaloración clínica a los 24 meses como el método diagnóstico de referencia, incluyendo las pruebas derivadas. En el PE existía una relación entre la presencia de calcio coronario y la elección de kilovoltajes altos (p = 0,02), que desaparecía en el PBD (p = 0,47). Los valores de SSDE y de DLP en el PBD fueron significativamente inferiores y presentaron menor dispersión que en el PE (9,22 mGy [RIQ 7,84-12,1 mGy] y 97 mGy*cm [RIQ 78-134 mGy*cm] contra 26,5 mGy [RIQ 21,3-36,3 mGy] y 253 mGy*cm [RIQ 216-404 mGy*cm]; p < 0,001 para las comparaciones de las medianas y de las dispersiones entre ambos grupos). La calidad global del PBD fue considerada buena o excelente en un 96% de los estudios y los parámetros que mostraron relación con esta última en un modelo multivariable (estadístico C = 0,792) fueron la frecuencia cardíaca (coeficiente estimado – 0,12 [intervalo de confianza del 95%: –0,2, –0,04; p < 0,01) y la SSDE (coeficiente estimado –0,26 [intervalo de confianza del 95%: –0,51, –0,01]; p < 0,05). El modificador CAD-RADS para un estudio no completamente diagnóstico fue usado en 2 ocasiones (4%), con una sensibilidad, una especificidad y una eficacia finales para el diagnóstico de enfermedad coronaria del 100, el 94% y el 94%, respectivamente. En el PE, el radiólogo elegía kilovoltajes más altos para la adquisición de la aTCC ante la presencia de calcio coronario en el score de calcio previo. La vinculación del kilovoltaje al índice de masa corporal en el PBD permitió reducir un 65% la dosis de radiación, con una calidad global excelente o buena en un 96% de los estudios y un rendimiento diagnóstico excelente. To evaluate the relation between the coronary calcium score and the posterior choice of kilovoltage according to radiologists’ criteria in a standard coronary CT angiography protocol to rule out coronary disease. To quantify the reduction in ionizing radiation after linking kilovoltage to patients’ body mass index in a low-dose protocol with iterative model reconstruction. To evaluate the image quality and diagnostic performance of the low-dose protocol. We compared anthropometric characteristics, calcium score, kilovoltage levels, size-specific dose estimates (SSDE), and the dose-length product (DLP) between a group of 50 patients who were prospectively recruited to undergo coronary CT angiography with a low-dose protocol and a historical group of 50 patients who underwent coronary CT angiography with the standard protocol. We correlated these parameters, the number of coronary segments that could not be evaluated with and without temporal padding, the attenuation, and the signal-to-noise ratio in the ascending aorta in the low-dose protocol with excellent imaging quality according to a semiquantitative scale. To calculate the diagnostic performance per patient, we used 24-month clinical follow-up including all tests as the gold standard. In the standard protocol, the presence of coronary calcium correlated with the selection of high kilovoltage (P = 0.02); this correlation was not found in the low-dose protocol (P = 0.47). Median values of SSDE and DLP were significantly (P< 0.001) lower and less dispersed in the low-dose protocol [9.22 mGy (IQR 7.84-12.1 mGy) vs. 26.5 mGy (IQR 21.3-36.3 mGy) in the standard protocol] and [97 mGy*cm (IQR 78-134 mGy*cm) vs. 253 mGy*cm (IQR 216-404 mGy*cm) in the standard protocol], respectively. The overall quality of the images obtained with the low-dose protocol was considered good or excellent in 96% of the studies. The parameters associated with image quality in a multivariable model (C statistic = 0.792) were heart rate (estimated coefficient, -0,12 [95% confidence interval: -0.2, -0.04]; P< 0.01) and the SSDE (estimated coefficient, -0,26 [95% confidence interval: -0.51, -0.01]; P< 0.05). The CAD-RADS modifier for a not fully evaluable or diagnostic study was used on two occasions (4%); the final measures for the diagnosis of coronary disease were sensitivity 100%, specificity 94%, and efficacy 94%. In the standard protocol, the radiologist selects higher kilovoltage for CT angiography studies for patients whose previous calcium score indicates the presence of coronary calcium. In the low-dose protocol, linking kilovoltage with body mass index enables the dose of radiation to be reduced by 65% while obtaining excellent or good image quality in 96% of studies and excellent diagnostic performance.

Abstract Funding Acknowledgements Type of funding sources: None. AIM [18F]FDG-PET/CT is part of the diagnostic algorithm for IE diagnosis. Increased [18F]FDG uptake with focal and heterogenous pattern at valve, intravalvular or perivalvular at visual analysis is consistent with IE. Diffuse, homogeneous or low valvular [18F]FDG uptake make diagnosis more challenging. Semiquantitative parameters may be of value in such case of equivocal PET findings; however, they are still not validated in IE. In this study we aim to assess the value of [18F]FDG PET/CT radiomics in IE diagnosis. Further, we build a model for radiomics-based prediction of PET/CT findings, patient classification and stratification as well as prediction of the final diagnosis. Materials and Methods We evaluated a series of [18F]FDG PET/CT scans in 447 patients (M:F =284:163, mean age 67± 16yrs), with suspected IE (519 valves, NVE = 109, PVE = 410), studied in 3 different centers between January 2015- 2020. Clinical, surgical data, antimicrobial treatment, microbiology and biochemistry, imaging and the DUKE/2015 ESC classification were collected. PET/CT images were semiautomatically segmented (Advantage Workstation, GE) and texture features extracted by LIFEx software. For the analysis we used absolute correlation exclusion criteria and PCA based dimensionality reduction, MANOVA test and LR for multivariate testing. Prior to model building by Random Forest (80% training sets, 20% test), we applied covariance matrix for correlated feature removal and SMOTE for preprocessing the imbalanced dataset. Results MANOVA and LR showed a positive contribution of radiomics in predicting PET/CT results and IE diagnosis, with a different signature in IE-positive/IE-negative patients (80% in training, 70% in validation). Of interest, the signature of patients with equivocal PET/CT findings was similar to IE-negative signature. Clustering-based stratification identify in two groups, one with milder disease presenting weak or no [18F]FDG uptake and one with more severe disease. Our LR models with incremental complexity (Table 1 and 2) demonstrated that the richer the information fed into the model the higher the performances, reaching 90% of AUC. However, the performance of model M5 and M6 is almost equal, suggesting a limited contribution of radiomics in classifying IE. Conclusion [18F]FDG PET/CT radiomics provide a limited, yet positive, contribution in the classification of EI. Nevertheless, radiomics was fundamental in defining PET outcome, thus it could support visual imaging assessment in particular when equivocal [18F]FDG findings are present. Further steps focusing on refinement of the IE diagnostic criteria, on explainable analysis on positive/negative patients to be transferred in equivocal cases. Ultimately, the identification of radiomic signature would help to define thresholds to discriminate between mild infection and severe IE, in a risk score fashion. Abstract Table 1 Abstract Table 2

Abstract Background Diagnosis of PVE by PET/CTA is based on visual and quantitative evaluation of morpho-metabolic features. The FDG uptake pattern is a main diagnostic criterion, but can be visually unclear and susceptible to subjectivity. The valve uptake index (VUI) is a new measure designed to provide a more objective indication of the distribution of metabolic activity. Purpose To validate the diagnostic accuracy of the valve uptake index (VUI) (SUVmax-SUVmean)/SUVmax, in patients with suspicion of prosthetic valve endocarditis (PVE). To establish a cut-off value that allows diagnosis of infection. Finally, to determine the incremental value of adding the VUI to the classic parameters for the diagnostis of PVE by PET/CT. Methods Retrospective analysis of 122 patients, with a conclusive diagnosis of definite or rejected PVE and who had undergone a cardiac PET/CTA scan. We measured the VUI and recorded the SUVmax, SUVratio, uptake pattern and the presence of endocarditis-related anatomic lesions. The diagnostic accuracy of these parameters was calculated. Results The VUI values were 0.54±0.1 vs. 0.36±0.08 in the definite PVE group vs. the rejected group, respectively (mean±SD; p<0.001). A cut-off value of VUI>0.45 showed a sensitivity, specificity and diagnostic accuracy for PVE of 85%, 90.3% and 87.4%, and significantly increased diagnostic ability for confirming endocarditis when combined with the standard diagnostic criteria. Conclusions The VUI had good diagnostic accuracy for PVE. The diagnostic power of currently used morphometabolic parametersis significantly increased by the addition of the VUI. Integration of the VUI in the diagnostic algorithm may clarify doubtful cases, and improve the diagnostic yield of PET/CTA. Funding Acknowledgement Type of funding sources: None.

Background: 18F-FDG-PET/CT-Angiography (PET/CTA) is a quite new technique providing improved diagnostic accuracy in prosthetic valve endocarditis (IE).While its high negative predictive value could be useful in rejecting IE even recently after surgery, there is little available data on the morphologic and metabolic features following prosthetic heart valve (PHV) implantation.Hence, early postoperative inflammation could be misdiagnosed as false-positive cases of infection.We prospectively evaluated a group of postoperative patients without suspected infection to define characteristic image findings after recent surgery and its short-term evolution. Methods:We prospectively recruited 37 patients divided into 2 subgroups between Jan-2015 and Feb-2016.They underwent seriated PET/CTA examinations at 1, 6 and 12 months after valve replacement surgery.We evaluated the metabolic features (FDG uptake distribution and intensity) and the possible anatomic changes (soft tissue reaction, post-surgical collections and perivalvular complications) following PHV implantation, and the temporal evolution features of these findings were evaluated.Results: A total of 111 PET/CTA scans were performed in the 37 patients.There were 19 aortic PHV (13 biological; 6 mechanical) and 18 mitral PHV (8 biological; 10 mechanical).FDG uptake was visually detectable in 79.3% of cases, with a diffuse and homogeneous distribution pattern in 93%.Quantitative analysis showed an average SUVmax of 4.46 ± 1.50, SUVmean 2.80 ± 0.62 and SUVratio of 2.28 ± 0.91 on the total of PET/CTA scans.There were no significant differences in FDG distribution pattern or uptake values between 1, 6 or 12 months, and no significant differences according to PHV type (mechanical vs. biological, SUVmax 4.67 ± 1.2 vs. 4.3 ± 1.69) or position (aortic vs. mitral, SUVmax 4.3 ± 1.41 vs. 4.63 ± 1.59).No anatomic changes or IE characteristic lesions were detected in any patient during follow-up. Conclusion:This data show that FDG uptake is often present in implanted PHV from the recent postoperative period.There is a characteristic pattern of FDG uptake in postsurgical inflammation with no associated anatomical lesions, features that remain stable during 1 year after implantation surgery and that help in differentiating inflammatory reactive changes from infection in most cases, even in recently implanted PHV.These findings question the 3-month safety period suggested by the current guidelines.

Abstract Background Late gadolinium enhancement (LGE) is the clinical reference standard for estimation of infarct extension and prediction of functional recovery following reperfused acute ST-segment elevation myocardial infarction (STEMI). Nevertheless, myocardial edema, microvascular obstruction and intramyocardial hemorrhage as well as the timing of image acquisition after contrast administration may influence the extent of LGE and underestimate the potential for recovery. Dobutamine stress testing has been recommended to more accurately predict functional recovery when infarct transmurality is between 25 to 75%. We hypothesized that cardiac magnetic resonance (CMR) tissue tracking strain analysis may provide additional value to LGE for the prediction of functional recovery. Methods In 370 patients with STEMI who underwent successful primary percutaneous revascularization and were studied with CMR within 3–5 days of the event, peak systolic longitudinal (LS), circumferential (CS) and radial (RS) strain were analyzed with routine SSFP images of 3 long-axis and a stack of short-axis slices (Tissue Tracking, CVI42®, Figure panel A and B). Inversion-recovery echogradient sequences were analyzed 20 minutes after contrast administration for LGE transmurality (Panel C). All per-segment analysis was performed according to the AHA 16-segment model. CMR was repeated at 6 months and functional recovery was defined as persistent normokinesia or improvement of wall motion score from baseline to 6-month CMR. Results At baseline CMR, of a total of 5920 segments 70.4% were normokinetic, 7.2% were hypokinetic, 21.9% were akinetic and 0.6% were dyskinetic. All strain parameters decreased significantly with worsening wall motion. At follow-up, 81.5% of the segments showed functional recovery. All strain parameters were significantly associated with functional recovery (p<0.001) and showed higher predictive value for improvement of wall motion than LGE transmurality (ROC AUC 0.713 LS, 0.710 CS, 0.683 RS and 0.660 LGE). For basal CMR dysfunctional segments, a CS <−10.7% showed the highest accuracy (66%) to predict wall motion improvement, with 58% sensitivity, 76% specificity, 75% positive predictive value (PPV) and 59% negative predictive value (NPV). These results were comparable to LGE transmurality <50% (65% accuracy, 59% sensitivity, 73% specificity, 74% positive predictive value and 58% negative predictive value). Nevertheless, adding CS analysis to a 50% LGE transmurality cutoff was the best combination for prediction of functional recovery and increased the overall accuracy to 70%, with 76% sensitivity, 64% specificity, 65% PPV and 75% NPV. CS analysis in an inferior STEMI Conclusions Acute CMR tissue tracking strain analysis complements LGE assessment for prediction of functional recovery following an STEMI. The combination of LGE infarct transmurality under 50% and a CS strain higher than −10.7% showed the highest accuracy for prediction of recovery of function.

A 40-year-old woman was evaluated at the outpatient clinic for pleuritic chest pain associated with exertional dyspnea of 2 months duration.She had no relevant personal or family history.Physical examination showed only a systolic murmur over the left carotid artery.She was referred for an echocardiogram which was relevant for a mild pericardial effusion.A diagnosis of acute pericarditis was considered and she was referred for a CMR which showed a non-dilated left ventricle with good systolic function and severe pericardial effusion.Furthermore, there was an homogeneous thickening of the aortic root (maximum 9 mm), with an irregular outer border, and which extended cranially up to the aortic arch and the supra-aortic branches.Tissue characterization showed isointense signal on both T1 and T2-weighted images.Angiography showed luminal stenosis of the origin of the left carotid artery.Unfortunately, at this point the patient demanded to terminate the study and LGE images were not acquired.She was admitted for further study and rapidly developed clinical instability; urgent pericardiocentesis was performed with drainage of 280 mL of a serous liquid.Control echocardiography showed reduction of the pericardial effusion and confirmed the periaortic circumferential thickening.Blood tests showed increased C-reactive protein levels and erythrocyte sedimentation rate and were negative for infectious and auto-imune diseases.Cardiac CT showed extension of the periaortic thickening to both coronary artery ostia as well as thickening and complete truncation of the right mid and lower lobe pulmonary arteries.Finally, FGD-PET/CT showed increased metabolism around the ascending aorta and right pulmonary hilum, suggestive of active inflammation.A final diagnosis of Takayasu's' arteritis type IIa (ascending aorta, aortic arch and its branches) with involvement of the coronary and pulmonary arteries was made.The patient was started on high-dose prednisolone, with clinical improvement and stabilization of inflammatory biomarkers as well as marked normalization of the PET/CT hypermetabolism.As the periaortic thickening and coronary involment persisted, she underwent a SPECT which showed no signs of myocardial ischemia.It was therefore decided to maintain conservative medical treatment and progressive tapering of steroid therapy.Takayasu's arteritis is a large vessel vasculitis that commonly has an age of onset < 40 years and predominantly affects women.It is characterized by large artery involvement (most frequently the aorta, carotid and subclavian arteries) and arterial narrowing or occlusion dominate the clinical picture.In up to one third of patients it also affects the pulmonary arteries.Steroid agents constitute the first-line therapy; however due to its agressive nature with multiple relapses, association of other immunossupressive drugs is generally required.

This article reviews the current imaging role of 18F–fluordeoxyglucose positron emission computed tomography (18F–FDG-PET/CT) combined with cardiac CT angiography (CTA) in infective endocarditis and discusses the strengths and limitations of this technique.