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Children diagnosed with diffuse midline gliomas (DMG) have an extremely poor overall survival: 9-12 months from diagnosis with currently no curative treatment options. Given DMG molecular heterogeneity, surgical biopsies are needed for molecular profiling and as part of enrolment into molecular-based and precision medicine type clinical interventions. In this study, we describe the results of real time profiling and drug testing at the diffuse intrinsic pontine glioma/DMG Research Centre at University Children's Hospital Zurich.Biopsies were taken using a frame based stereotactic robot system (NeuroMate®, Renishaw) at University Children's Hospital Zurich. Tissue samples were evaluated to confirm diagnosis by H3K27M and H3K27 trimethylation loss. Genomic analyses were done using a variety of platforms (INFORM, Oncomine, UCSF500 gene panel). Cell lines were developed by mechanical tissue dissociation and verified by either sequencing or immunofluorescence staining confirming H3K27M mutation and used afterwards for drug testing.Twenty-five robot-assisted primary biopsies were successfully performed. Median hospital stay was 2 days (range 1-4 days). Nine low-passage patient-derived cells were developed, whereas 8 cell lines were used to inform response to clinically relevant drugs. Genome and RNA expression were used to further guide treatment strategies with targeted agents such as dual PI3K/mTOR inhibitor paxalisib.We established a systematic workflow for safe, robot-assisted brainstem biopsies and in-house tissue processing, followed by real-time drug testing. This provides valuable insights into tumour prognostic and individual treatment strategies targeting relevant vulnerabilities in these tumours in a clinically meaningful time frame.

Funding Acknowledgements Type of funding sources: None. Background Late gadolinium enhancement (LGE) has been proposed as an independent predictor of ventricular arrhythmias. Purpose The purpose of this study was to assess if myocardial scar characterization could enhance the risk stratification for life-threatening arrhythmias and sudden cardiac death (SCD). Methods We included patients with an indication for ICD or CRT-D implantation who underwent cardiac magnetic resonance for clinical proposes since February/2018 and in whom a 3D-LGE dataset was obtained. Patients with channelopathies (n=2) or inappropriate imaging quality (imaging artifacts; n=7) were excluded. Scar characterization using ADAS software was performed in 3D-LGE datasets in all but 5 patients, where 2D datasets were used. The primary endpoint was the composite of appropriate ICD therapy (classified as ATP or shock) or SCD. Results A total of 75 patients were analysed (mean age 63 ± 13 years; 83% male; mean LVEF 31 ± 13%; 50 patients with ischemic and 25 with non-ischemic cardiomyopathy; 14 patients received a device in the setting of secondary prevention). During a median follow-up of 1.4 years (IQR 0.7 – 2.4 years) there were 15 events (12 appropriate ICD therapies [8 shocks and 4 ATP] and 3 SCD). No statistically significant differences were found between patients with or without events in terms of scar mass, border zone (BZ) mass, BZ channels (BZC), BZC mass, number of channels detected, and scar heterogeneity (BZ mass / scar mass ratio) - all p values > 0.2 – Figure. Restricting the analysis to only primary prevention cases yielded similar results. Overall, 11 patients did not show any channel. Two of these experienced an arrhythmic event, yielding a negative predictive value of 80% (95% CI 75-83%) for the absence of channels. Conclusion In this cohort with still relatively limited follow-up duration, no single parameter reflecting scar tissue characterization was able to predict appropriate device therapies or sudden cardiac death.

Funding Acknowledgements Type of funding sources: None. Background Although cardiac magnetic resonance (CMR) is the gold standard for planning ventricular tachycardia (VT) ablation, its accuracy is hindered in patients with implanted cardiac defibrillators (ICD) and resynchronization therapy (CRT). Cardiac computed tomography (CT) has emerged as an alternative for ablation planning in these patients. This pilot study aimed to evaluate the relationship between wall thickness (WT) on CT and voltage of electrical potentials on endocardial electroanatomic mapping (EAM) in patients with ischemic cardiomyopathy. Methods Single centre retrospective study enrolling consecutive patients with ischemic cardiomyopathy referred for endocardial VT ablation that underwent cardiac CT for procedure planning since 2021. Patients were excluded if EAM had < 1000 data points. ADAS 3D® software was used to analyse CT images, automatically segmenting the left ventricle (LV) into the 17 American Heart Association segments and calculating end-diastolic WT for each one. Four standardized views (anterior-posterior, posterior-anterior, superior, and inferior) of the segmented LV on ADAS 3D® were used to aid in manual segmentation of the EAM. The endocardial voltage maps were created using CARTO3® software (Figure 1). For each patient, EAM was interpreted to create 2 different bulls’ eye maps, according to the presence or absence of bipolar potentials < 0.5 (dense scar) or < 1.5mV (low voltage). Only segments with >20% extension of low bipolar voltage were considered as altered. Results We included a cohort of 8 patients (mean age 67±12 years, 87.5% male, median LVEF of 32% [IQR 25-49]). All but one patient had implanted cardiac device (6 ICD, 1 CRT-D). Cardiac CT was performed 1 day (IQR 0-2) before the ablation. Overall, 136 segments were analysed, 8 of which did not have voltage information. Of the remaining 128, 51 (39.8%) had dense scar and 57 (41.9%) had low voltage. There was a good correlation between mean WT and the presence or absence of both dense scar (area under de curve (AUC) 0.799, p Conclusion WT measured by CT appears to have a strong correlation with dense scar and low voltage in EAM in patients with ischemic cardiomyopathy undergoing VT ablation. This technique may be useful to plan interventions in patients in whom CMR is not feasible.

It is unknown whether impaired brain structure after congenital blindness is reversible if sight is restored later in life. Using structural magnetic resonance imaging, visual cortical surface area and cortical thickness were assessed in a large group of 21 sight-recovery individuals who had been born blind and who months or years later gained sight through cataract removal surgery. As control groups, we included 27 normally sighted individuals, 10 individuals with permanent congenital blindness, and 11 sight-recovery individuals with a late onset of cataracts. Congenital cataract-reversal individuals had a lower visual cortical surface area and a higher visual cortical thickness than normally sighted controls. These results corresponded to those of congenitally permanently blind individuals suggesting that impaired brain structure did not recover. Crucially, structural brain alterations in congenital-cataract reversal individuals were associated with a lower post-surgery visual acuity. No significant changes in visual cortex structure were observed in sight-recovery individuals with late onset cataracts. The results demonstrate that impaired structural brain development due to visual deprivation from birth is not fully reversible and limits functional recovery. Additionally, they highlight the crucial importance of prevention measures in the context of other types of aberrant childhood environments including low socioeconomic status and adversity.

Supplementary Figure 2 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 1 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 3 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Table 1 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 4 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Legends of Supplementary Tables, and Supplementary References

Documentation of model components, interactions and regulatory rules.

Epithelial-to-mesenchymal transition (EMT) has been associated with cancer cell heterogeneity, plasticity, and metastasis. However, the extrinsic signals supervising these phenotypic transitions remain elusive. To assess how selected microenvironmental signals control cancer-associated phenotypes along the EMT continuum, we defined a logical model of the EMT cellular network that yields qualitative degrees of cell adhesions by adherens junctions and focal adhesions, two features affected during EMT. The model attractors recovered epithelial, mesenchymal, and hybrid phenotypes. Simulations showed that hybrid phenotypes may arise through independent molecular paths involving stringent extrinsic signals. Of particular interest, model predictions and their experimental validations indicated that: (i) stiffening of the extracellular matrix was a prerequisite for cells overactivating FAK_SRC to upregulate SNAIL and acquire a mesenchymal phenotype and (ii) FAK_SRC inhibition of cell–cell contacts through the receptor-type tyrosine-protein phosphatases kappa led to acquisition of a full mesenchymal, rather than a hybrid, phenotype. Altogether, these computational and experimental approaches allow assessment of critical microenvironmental signals controlling hybrid EMT phenotypes and indicate that EMT involves multiple molecular programs.Significance:A multidisciplinary study sheds light on microenvironmental signals controlling cancer cell plasticity along EMT and suggests that hybrid and mesenchymal phenotypes arise through independent molecular paths.

Phenotypes reached upon systematic in silico analysis of single and double mutants.

Supplementary Methods

Supplementary Figures S1-S8

Alterations in the expression or function of cell adhesion molecules have been implicated in all steps of tumor progression. Among those, P-cadherin is highly enriched in basal-like breast carcinomas, playing a central role in cancer cell self-renewal, collective cell migration and invasion. To establish a clinically relevant platform for functional exploration of P-cadherin effectors in vivo, we generated a humanized P-cadherin Drosophila model. We report that actin nucleators, Mrtf and Srf, are main P-cadherin effectors in fly. We validated these findings in a human mammary epithelial cell line with conditional activation of the SRC oncogene. We show that, prior to promoting malignant phenotypes, SRC induces a transient increase in P-cadherin expression, which correlates with MRTF-A accumulation, its nuclear translocation and the upregulation of SRF target genes. Moreover, knocking down P-cadherin, or preventing F-actin polymerization, impairs SRF transcriptional activity. Furthermore, blocking MRTF-A nuclear translocation hampers proliferation, self-renewal and invasion. Thus, in addition to sustaining malignant phenotypes, P-cadherin can also play a major role in the early stages of breast carcinogenesis by promoting a transient boost of MRTF-A–SRF signaling through actin regulation.

Clinical overt cardiac cachexia is a late ominous sign in patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF). The main goal of this study was to assess the feasibility and prognostic significance of muscle mass quantification by cardiac magnetic resonance (CMR) in HF with reduced LVEF. HF patients with LVEF

Resumo Introducao e objetivos Os anticoagulantes diretos (direct anticoagulants, DOACs) mudaram o panorama do tratamento da fibrilhacao auricular (FA), trazendo novos desafios de acessibilidade e adesao terapeutica. O objetivo deste estudo foi avaliar a adesao terapeutica com DOACs, e os seus fatores determinantes, numa populacao de doentes com FA. Metodos Estudo retrospetivo de centro unico incluindo doentes com FA nao valvular sob terapeutica com DOAC seguidos em consulta de Cardiologia, cuja primeira prescricao de DOAC foi realizada entre 1 de abril de 2016 e agosto de 2018. Foram contabilizadas as embalagens de DOAC levantadas desde a primeira prescricao ate 31 de agosto de 2018, utilizando a Prescricao Eletronica Medica. Foi calculada a adesao a terapeutica atraves da divisao entre o numero de dias cobertos pela dispensa efetiva na farmacia e os dias sob terapeutica. Definiu‐se “nao adesao” como uma adesao inferior a 90%. Resultados Foram incluidos 264 doentes (120 homens, idade media 74 ± 12 anos). O score CHA2DS2VASC mediano foi 3 (IIQ 2‐5) e o score HAS‐BLED mediano foi 1 (IIQ 1‐2). Os DOAC rivaroxabano, apixabano, dabigatrano e edoxabano foram prescritos em 45%, 41%, 24% e 13% dos doentes, respetivamente. Ao longo do periodo avaliado, 51 doentes (19%) tomaram pelo menos dois DOACs diferentes. Os doentes estiveram sob DOAC durante uma mediana de 439 dias (IIQ 269‐638), durante os quais aderiram a terapeutica em mediana 90% (IIQ 75‐100%) do tempo. Cerca de metade (51%) dos doentes foi considerada nao aderente; a maior duracao da terapeutica (OR ajustado de 1,06/mes, IC95% 1,03‐1,08, p Conclusao Metade dos doentes (51%) com FA sob DOAC foram classificados como nao aderentes (adesao

Background Functional mitral regurgitation (fMR) severity grading by 2D transthoracic echocardiography (TTE) can be a complex task, especially in patients where PISA assumptions are not met (eg. non-circular orifice or multiple jets). Cardiac magnetic resonance (CMR) can provide further insight on the hemodynamic burden of fMR by accurately determining mitral regurgitant fraction (RegFrac). Our goal was to investigate the concordance and disagreement between the two modalities in assessing fMR. Methodology Single-center prospective study of fMR patients performing same-day TTE and CMR from Feb to Dec 2021. MR severity was classified according to 2020 ACC consensus: grade I (mild; EROA Results A total of 36 patients were included (age 65±14y; 74% male; left ventricle [LV] ejection fraction by TTE and CMR 35±13% and 34±11%, respectively). Mean RVol and EROA by TTE were 28±11mL and 0.18±0.8 cm2. Mean RVol and Regfrac by CMR were 20±13 mL and 25±12%, respectively. A moderate correlation between RVol by TTE and CMR was found (Pearson's R 0.58, p=0.001). According to TTE, there were 20 patients (56%) with grade I fMR, 12 patients (33%) with grade II fMR and 4 patients (11%) with grade III fMR. All patients considered to have mild (grade I) fMR by TTE had a RegFrac Conclusion Using the criterion of RegFrac ≥35%, CMR re-classifies (half for each side) the patients with moderate and moderate-to-severe regurgitations by TTE. Recognizing, overcoming and resolving the disagreements between the techniques is the way forward to reach excellence. Funding Acknowledgement Type of funding sources: None.

Background The 2021 Guideline for the Evaluation of Chest Pain supports the use of coronary artery calcium (CAC) score as a reasonable first-line test to identify patients with a low likelihood of obstructive coronary artery disease (CAD) who may not require additional testing (class IIa, LOE B). However, a recent study from a large cohort of Northern European patients raised concerns about the added diagnostic value of CAC=0 in younger patients. The aim of this study was to assess the influence of age on the value of CAC=0 in symptomatic patients undergoing coronary computed tomography angiography (CCTA). Methods We conducted a two-center cross-sectional study assessing symptomatic patients with suspected CAD who underwent CAC score and CCTA. Key exclusion criteria were age Results A total of 2043 patients (mean age 60±11 years, 60% women) of whom 990 (48.5%) had a CAC score of 0 were included in the analysis. Symptom characteristics were: 38% non-anginal chest pain, 30% atypical angina, 19% dyspnea, and 13% typical chest pain. Overall, the prevalence of obstructive CAD was 12.8% (n=262). Pretest probability of obstructive CAD increased progressively with age, from 6.0% in patients young than 50 years to 20.7% in those 70 years or older. Contrariwise, the prevalence of patients with a CAC score = 0 decreased from 77% in patients younger than 50 years, to 26% in those who where 70 years or older. The added diagnostic value of a CAC score = 0 was lower in younger patients, with negative likelihood ratios ranging from 0.36 (64% decrease in the likelihood of CAD) in patients younger than 50 years, to 0.09 and 0.10 (∼90% decrease in the likelihood of CAD) in those aged 60–69 years and 70 years or older, respectively – Figure 1. Despite this, the prevalence of obstructive CAD among patients with a CAC score = 0 was low across all age groups: 2.4% (i.e., NPV = 97.6%) in those younger than 50 years, 3.0% (NPV = 97.0%) among those aged 50–59 years, 1.5% (NPV = 98.5%) in patients between 60 and 69 years, and 2.0% (NPV = 98.0%) among those 70 years or older. Conclusions In a cohort of symptomatic patients undergoing CCTA for suspected CAD, the added diagnostic value of a CAC score of zero decreases significantly at younger ages. However, this “diminishing return” of CAC in younger patients if offset by their lower pretest probabilities, yielding high negative predictive values independently of age. Funding Acknowledgement Type of funding sources: None.

Background Left ventricular (LV) remodeling in patients with severe aortic valve stenosis (AS) is a complex process that goes beyond hypertrophic response and may involve reparative/replacement fibrosis. Currently, cardiac magnetic resonance (CMR) is the gold-standard imaging technique for detecting focal myocardial fibrosis through late gadolinium enhancement (LGE). However, myocardial fibrosis prevalence and distribution is quite variable among series. Our goal was to assess LGE prevalence and distribution pattern in severe symptomatic high-gradient AS. Methodology Single-center prospective cohort of 132 patients with severe symptomatic high-gradient AS (mean age 73±11 years; 48% male, mean valvular transaortic gradient 60±20 mmHg; mean aortic valve area 0.7±0.2 cm2/m2; mean LV ejection fraction by 2D echocardiogram 58±9%), all with normal flow (except one) undergoing surgical aortic valve replacement. Those with previous history of acute myocardial infarction, ischemic cardiomyopathy or other cardiomyopathy were excluded. All patients performed 1.5T CMR assessment with LV myocardium tissue characterization prior to surgery. Segmental LGE presence was assessed by two independent operators and classified according to the AHA 16 segment model, using 5-standard deviations from remote myocardium as the signal intensity cut-off for LGE identification and quantification. Results Overall, 96 patients (74%) had non-ischemic LGE (median LGE mass 3.2 g [IQR 0.2–8.3] g; median percentage of LGE myocardial mass 2.5% [IQR 0.1–6.1]%); 22 patients [17%] with exclusively junctional LGE); in one patient an incidental ischemic scar (subendocardial distribution) was identified. No cases of subepicardial distribution were found. Intramyocardial LGE was most frequently observed in basal and mid-anterior and inferior interventricular septum – see Figure 1. In these segments, LGE was most often junctional at right-ventricular insertion points (54%), followed by mid-wall LGE (32%) or both sites involvement (14%). Conclusion LGE is frequent in symptomatic high-gradient AS patients with preserved left ventricular ejection fraction, most often presenting as junctional enhancement in basal/mid-anterior and inferior interventricular septum. Future studies may address whether distinct LGE patterns may impact patient prognosis. Funding Acknowledgement Type of funding sources: None.

Background Exercise capacity is usually reduced in Fontan patients, however there is a subset of patients who have normal exercise capacity and better outcomes, the “Super-Fontans”. The aim of this study was to characterize a cohort of Fontan patients undergoing cardiopulmonary exercise testing (CPET) and identify predictors of better functional capacity. Methods Single center retrospective analysis of consecutive Fontan patients aged >10 years old who underwent CPET, between March 2018 and May 2021. Peak respiratory exchange ratio1.05 defined maximal CPET. Peak VO2 (pVO2) as a percentage of its predicted value was used as reference value to stratify patients in tertiles. Patients in 3rd tertile, with a percentage predicted pVO2 superior to 75%, were considered good-performers. Blood tests and transthoracic echocardiogram (TTE) were performed on the same day. Additional data were collected from electronic charts. Results In total, 49 patients were included (mean age 19±7 years old, 67% male) with intra or extracardiac conduit implanted in mean 12±7 years prior to the CPET. The most common primary diagnoses were tricuspid/pulmonary atresia (43%), followed by unbalanced complete AV septal defect (14%) and double inlet left ventricle (14%). 12 patients had a systemic right ventricle. All, except 5 patients, had preserved systolic ventricular function and 37% had moderate to severe AV regurgitation. The majority had normal hemoglobin levels (median 15.6 g/dL), hepatic enzymes (median total bilirubin 0.8 mg/dL), renal function (median creatinine 0.8 mg/dL) and low NT-proBNP (median 122 pg/mL). All patients had maximal CPET, median %VO2 at VT1 was 57% of peak and mean pVO2 was 66±14% of the predicted. Most patients (69%) showed exercise limitation due to cardiovascular cause, followed by O2 desaturation, present in 22% of CPETs. The age of Fontan completion was not associated with functional capacity (p=0.6). The good-performer group comprised 13 patients (27%), all in sinus rhythm, of which 10 were physically active. Compared with the remainder, this group had higher VO2 at VT1 (18.7 vs. 14.6, p=0.01) and VO2 at VT2 (25.9 vs. 22.1, p=0.02), both in mL/kg/min. Also, peak heart rate (% predicted) (90 vs. 81, p=0.03) was higher in this subgroup – fig.1. Conversely, differences on TTE parameters (GLS and AV valve regurgitation) and blood biomarkers were not statistically significant. On multivariable analysis, no single variable predicted better functional capacity. Conclusion In our Fontan cohort, most patients had reduced exercise capacity, largely due to cardiovascular dysfunction. However, “Super-Fontans” stood out as they had a higher anaerobic threshold illustrating their better physical condition. These findings highlight the role of regular physical activity in Fontan patients as a cornerstone for better functional capacity. Funding Acknowledgement Type of funding sources: None.

Introduction Calcium score of the aortic valve (CaScAoV) is recommended as a supporting tool to assist in the grading of aortic stenosis (AS) severity when echocardiographic assessment is inconclusive. However, a significant proportion of patients have CaScAoV values within a “grey zone” between the “unlikely” and “likely” thresholds. The purpose of this study was to assess the potential usefulness of indexing CaScAoV to the area of the aortic annulus, in order to improve the discriminative power of CaScAoV in this subset of patients. Methods Consecutive patients evaluated at a single center TAVI program were retrospectively identified and included in the analysis if cardiac CT and echocardiography were performed within a 6-month timeframe. Those with LVEF Results A total of 655 patients were included (282 men (43.1%), median age 83 years [IQR 79–86]). AS was considered severe by echocardiographic criteria in 587 patients (89.6%), and moderate in the remainder. Median transvalvular gradient was 49 mmHg (IQR 43–59), and median CaScAoV values were 3329 (IQR 2356–4500) for men, and 1995 (IQR 1462–2781) for women. Overall, 77 patients (11.7%) had CaScAoV values in the “grey zone”, of which 24 (31.2%) had moderate AS (Figure 1). Patients within this region of uncertainty were no different form the others in terms of age, sex, annulus size and body surface area. In this subset of patients, indexing CaScAoV to aortic annulus area showed good discriminative power to identify severe AS (AUC 0.69, 95% CI 0.56–0.81, p=0.008). Using previously established thresholds (>300 AU/cm2 for women and >500 AU/cm2 for men), 48 patients (62.3%) were correctly reclassified (net reclassification index of 0.45, p=0.03). These findings were similar for both sexes. Conclusion In patients undergoing cardiac CT for known or suspected severe AS with CaScAoV values within the “grey zone”, indexing CaScAoV to the area of the aortic annulus improves the classification of AS severity and may decrease diagnostic uncertainty. Funding Acknowledgement Type of funding sources: None.

Background Recently, the European Society of Cardiology issued new algorithms to estimate the 10-year risk of atherosclerotic cardiovascular disease (ASCVD), along with new age-specific thresholds to classify individuals as low-to-moderate, high, or very-high risk. The aim of this study was to compare the latest SCORE-2 model with the older SCORE (Systematic COronary Risk Evaluation) in their ability to identify individuals with high coronary artery calcium score (CACS), and assess the relationship between potential eligibility for statin therapy and CACS. Methods Individuals 40–69 years old without diabetes or known ASCVD were identified in a single center registry of patients undergoing CACS and coronary CT angiography for suspected coronary artery disease. SCORE and SCORE-2 were calculated and used with each patient's untreated LDL-C values to assess eligibility for statin therapy. High CACS was defined as an Agatston score ≥100. Results A total of 389 pts (46% men, mean age 58±8 years) were included, of which 15% (n=60) were active smokers. The mean systolic blood pressure and untreated LDL-C values were 136±17 mmHg and 155±65 mg/dL, respectively. The proportion of patients classified as low-to-moderate risk, high risk, and very high risk was 93%, 6% and 1% using the SCORE algorithm, and 42%, 44%, and 14% using SCORE-2, respectively. Overall, 218 patients (56%) would have their risk category revised upwards, while no patients would be downgraded. The median CACS was 5 (IQR 0–71 AU), with 166 patients (43%) having CACS = 0, and 81 (21%) presenting CACS values ≥100. SCORE and SCORE-2 showed similar discriminative power to identify patients with CACS ≥100 (C-statistic 0.77, 95% CI 0.71–0.82, vs. 0.75, 95% CI 0.69–0.80, P=0.109 for comparison]. The up-reclassification of risk conveyed by SCORE-2 affected patients across all categories of CACS (Fig. 1). The proportion of patients in whom statin therapy would generally be indicated was higher with the SCORE-2 criteria vs. the SCORE algorithm (61% vs. 29%, respectively, p Conclusion Even though the discriminative power of SCORE-2 is similar to the older SCORE, the introduction of age-specific thresholds results in the up-reclassification of risk in roughly half of the patients. The application of SCORE-2 will broaden statin eligibility overall, not only in patients with high atherosclerotic burden, but also in those with CACS = 0. These findings support the use of risk modifiers in selected patients to improve the effectiveness of statin therapy. Funding Acknowledgement Type of funding sources: None.

Introduction Mitral balloon valvuloplasty (MBV) is the guideline recommended treatment for symptomatic severe mitral stenosis (MS) with suitable anatomy, but is often deemed transitory. However, data on very-long term echocardiographic follow-up is scarce. The aim of our study was to describe clinical and echocardiographic outcomes in patients previously submitted to MBV for rheumatic MS. Methods We conducted a single-centre retrospective study enrolling patients previously submitted to MBV for rheumatic MS from 1990 until 2021. Follow-up was considered until last registered echocardiographic re-evaluation. Patients without electronic health records available were excluded. The primary endpoint was a composite of all-cause death or need of surgery. Results A total of 193 patients were included (15.5% male, with a mean age of 52±15 years at the time of MBV, 60.6% with permanent atrial fibrillation). During a mean follow-up of 11±8 years, 87 (45.1%) patients implanted a mitral valve prosthesis, 4 (2.1%) were submitted to surgical mitral valvuloplasty and 30 (15.5%) died without being reinterventioned. Moreover, a total of 23 (11.9%) embolic events were registered – 21 strokes, 1 pulmonary embolism and 1 acute lower limb embolism. Overall, 133 patients (68.9%) survived more than 5 years, 95 (49.2%) more than 10 years and 56 (26.9%) more than 15 years since MBV without meeting the primary endpoint. The maximum follow-up without intervention was 32 years. Concerning patients submitted to surgery, the mean time from MBV until operation was 9.4±7.3 years (minimum 8 days; maximum 29.3 years). In regard to echocardiographic long-term outcomes on alive non-operated patients (mean follow-up of 12±9 years), 52.8% remain with mild MS, 91.6% with mild or no mitral regurgitation and 77.6% with mild or no tricuspid regurgitation. Furthermore, only 20.4% have right ventricle dysfunction (defined as a TAPSE 45 mmHg), and 6.8% have residual interatrial communication. Conclusion MBV is a minimally invasive procedure that has an important benefit in a very significant proportion of patients with rheumatic mitral stenosis, with potential benefit that may last more than three decades without need for another invasive intervention. Funding Acknowledgement Type of funding sources: None.

Background The North American 2021 Chest Pain Guidelines recommend not testing stable patients with low pretest likelihood of obstructive coronary artery disease (CAD), defined as pretest probability The purpose of this study was to assess the results of three different testing strategies for patients with pretest probability 0; C) perform CCTA in all. Methods We conducted a two-center cross-sectional study assessing symptomatic patients with suspected CAD who underwent CAC score and CCTA. Patients with known CAD, suspected acute coronary syndrome, or symptoms other than chest pain or dyspnea were excluded. Pretest probability of obstructive CAD was calculated based on age, sex and symptom typicality. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. Results A total of 2259 patients were screened, of which 1385 (61.3%) had pretest probability 0 (n=599), 21.2% (n=127) had obstructive CAD. The results that would be reached with each of the 3 diagnostic strategies are presented in Figure 1. The number of patients needed to scan with strategy B (CAC as gatekeeper) vs. A (no testing) to identify one patient with obstructive CAD was 11, whereas the number needed to scan with strategy C (CCTA for all) vs. strategy B was 91. Conclusions Not testing patients with suspected CAD and pretest likelihood Funding Acknowledgement Type of funding sources: None.

Background Left ventricular (LV) hypertrophy is a common expected finding in aortic stenosis (AS) patients. Cardiac magnetic resonance (CMR) plays an important role as a non-invasive method for determining LV mass and volume, and to characterize the LV remodeling response in AS. Aim To assess the prevalence, to describe the patterns and evolution of LV remodeling (by CMR) in AS patients referred for surgical aortic valve replacement (AVR). Methods Single-center prospective cohort of 132 consecutive patients (73 years [68–77 years], 49% men] with severe AS: mean transaortic pressure gradient (AVmean): 61±1.5 mmHg; aortic valve area (AVA): 0.7±0.1 cm2, referred for surgical AVR, with no previous history of ischemic cardiomyopathy. Before surgery, all patients underwent electrocardiogram, complete transthoracic echocardiogram (TTE) and CMR for LV assessment and tissue characterization (mean LV indexed mass [LVMi]: 80.3±26.5 g/m2; mean end-diastolic LV indexed volume [LVEDVi]: 84.4±24.5 mL/m2 and median geometric remodeling ratio [M/V]: 0.95 g/mL [IQR 0. 81–1.08 g/mL]). Patterns of LV remodeling were investigated before and after AVR by CMR measurements of LVMi, LVEDVi and M/V. Besides normal LV ventricular structure, four other patterns were considered: concentric remodeling, concentric hypertrophy, eccentric hypertrophy, and adverse remodeling (Figure 1). Results Overall, 43% (n=58) of the patients had concentric hypertrophy, 30% (n=40) concentric remodeling, 22% (n=29) normal ventricular geometry, 4% (n=5) eccentric hypertrophy and in two patients we observed an adverse remodeling pattern. AVR was performed in 80 patients. At the 3rd to 6th month post-AVR assessment, LV remodeling changed to: normal ventricular geometry in 46%, concentric remodeling in 31%, concentric hypertrophy in 19%, eccentric hypertrophy in 3% and adverse remodeling in only one patient (Figure 1). Conclusions In this group of patients with severe aortic stenosis, concentric hypertrophy was not the sole pattern of LV remodeling and two out of every five still presented a normal ventricular geometry and mass as assessed by CMR. LV response was dynamic after AVR which stands for complex and multifactorial interaction in these group of patients despite similar valvular pathophysiology and therapeutic intervention. Funding Acknowledgement Type of funding sources: None.

Background Left ventricular (LV) hypertrophy is a known compensatory mechanism to pressure overload in aortic stenosis (AS) patients. However, by cardiac magnetic resonance (CMR) different patterns of LV adaptation are seen in this group of patients. Aim To describe the patterns of LV adaptation (by CMR) and to analyze its structure and function indexes in AS patients referred for surgical aortic valve replacement (AVR). Methods We prospectively studied 134 consecutive patients (age: 73y [IQR 68–77y], 49% men) with severe symptomatic AS - mean transaortic pressure gradient (AVmean): 61±1.5 mmHg; mean aortic valve area: AVA): 0.7±0.1 cm2, referred for surgical AVR with no previous history of ischemic cardiomyopathy or other. All patients underwent electrocardiogram, 2D transthoracic echocardiogram (TTE) and cardiac magnetic resonance (CMR) before surgery for LV assessment and tissue characterization. Five patterns of LV structure were considered: normal ventricular structure (normal LV mass/volume ratio [M/V], normal LVMi and normal indexed LV end-diastolic volume (LVEDVi); concentric remodeling: increased M/V, normal LVMi; concentric hypertrophy: increased M/V and LVMi; eccentric hypertrophy: increased LVMi and LVEDVi, normal M/V and ejection fraction; and adverse remodeling: dilated left ventricle, increased LVMi and normal M/V in the context of an impaired ejection fraction. Echocardiogram and CMR structural and functional indexes were compared between these groups. Results At baseline study, at CMR: mean LV indexed mass [LVMi]: 80.3±26.5 g/m2; mean end-diastolic LV indexed volume [LVEDVi]: 84.4±24.5 mL/m2 and median geometric remodeling ratio [M/V]: 0.95 g/mL [IQR 0. 81–1.08 g/mL]. Overall, 22% patients had normal LV structure, 30% concentric remodeling ventricular geometry, and two patients had an adverse remodeling pattern. LV hypertrophy was the most prevalent pattern and occurred in 48% of subjects (concentric 43%; eccentric 4%). In our cohort, the severity of AS (AVmean (p Conclusions In our cohort, AS patients presented several distinct patterns of LV remodeling. Disease severity, functional repercussion and loading conditions are distinct between them. Funding Acknowledgement Type of funding sources: None.

Background In patients with severe aortic stenosis (AS), left ventricular (LV) remodeling is believed to be a compensatory adaptive process which should reverse after aortic valve intervention. However, this is not always the rule and remodeling persistence may negatively impact post-procedural outcomes and survival. Aim To assess the prevalence and predictors of morphological LV reverse remodeling in severe symptomatic AS patients after surgical aortic valve replacement (AVR). Methods We prospectively studied 75 patients (72y [68–77y], 45% male) with severe symptomatic AS - mean gradient (AVM): 61±17mmHg; mean indexed aortic valve area (AVAi) 0.41±0.10 cm2/m2 with no previous history of ischemic cardiomyopathy, all with high gradient, 4 with low-flow, 81% with hypertension, 27% with type 2 diabetes mellitus and 35% patients with stage 3 chronic kidney disease: median MDR creat clearance: 70.4mL/min [40–102]. All patients performed pre-operative cardiac magnetic resonance (CMR) at a mean period of 3.4 months (0–17 months) before AVR and at the 3–6th months after AVR, for LV reverse remodeling assessment. It was defined as at least the occurrence of one of the following: >15% reduction in LVEDVi; >15% reduction in LVMi by CMR; >10% reduction in geometric remodeling ratio. Clinical, AV severity data, preoperative functional LV and tissue characterization data were analyzed at multivariate regression to predict the occurrence of LV reverse remodeling. Results Overall, at pre-operative CMR: mean LV indexed mass (LVMi): 82±28.9 g/m2; mean end-diastolic LV indexed volume (LVEDVi): 87.4±26.6 mL/m2; mean geometric remodeling (LV mass/end-diastolic volume): 0.92±0.2 g/mL. After AVR, at echocardiographic evaluation, no patient had prosthetic obstruction or prosthetic patient mismatch: median LV-Ao gradient 12mmHg [9.1–14 mmHg]; 5 of them had mild paravalvular regurgitation. LV reverse remodeling occurred in 65 patients (88%) (Figure 1A) and these were younger, had significantly smaller preoperative AVAi and higher valvular gradients (Figure 1B). At multivariate analysis, only preoperative AVAi remained an independent predictor (odds ratio 0.85, 95% CI 0.735–0.984, p=0.029). Conclusions In this prospective cohort of patients LV reverse remodeling after surgical AVR was highly frequent, occurring in almost nine out of every ten patients. Funding Acknowledgement Type of funding sources: None.

Background The usefulness of implantable cardioverter defibrillators (ICD) for primary prevention of arrhythmic sudden cardiac death (SCD) in patients with non-ischemic dilated cardiomyopathy (DCM) has been questioned. Efforts to improve risk stratification have included scores such as the “MADIT-ICD benefit score”, and the use of late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR). The purpose of this study was to evaluate the potential usefulness of these two tools to assess the risk of life-threatening arrhythmias in patients with non-ischemic DCM undergoing ICD implantation for primary prevention of SCD. Methods We conducted a single-center retrospective study of consecutive patients who underwent contrast-enhanced CMR before ICD implantation for primary prevention of SCD. Patients with ischemic cardiomyopathy were used as reference. Patients with non-dilated cardiomyopathies were excluded. The arrhythmic component of the MADIT-ICD benefit score (VT/VF score) was calculated for each patient, and considered high if ≥7, as recommended. The primary endpoint was the occurrence of SCD or life-threatening arrhythmias (VF or VT >200 bpm). Follow-up was performed by device interrogation in all patients except those who suffered SCD. Results A total of 151 patients (93 ischemic, mean age 62±13 years, 75% male) with mean left ventricular ejection fraction (LVEF) of 27±8% were included. Overall, 72% (n=67) ischemic and 45% (n=26) non-ischemic patients had scores ≥7 and were considered high-risk. LGE was present in all patients with ischemic cardiomyopathy, and in 76% (n=44) of patients with non-ischemic DCM. During a median follow-up of 21 (8–38) months, 21 patients (13.9%, 11 ischemic and 10 non-ischemic) met the primary endpoint. Overall, the event-free survival of non-ischemic patients was similar to that of ischemic patients (log rank p=0.269). In patients with non-ischemic DCM, there were 7 arrhythmic events (26.9%) in those with MADIT-ICD VT/VF scores ≥7, and 3 events (9.4%) in those with scores In the same population, there were 10 arrhythmic events (23%) in patients with LGE, but no events in patients without LGE (log rank p=0.036). LVEF was similar in patients with and without arrhythmic events (26±8% vs. 27±7%, p=0.717), and in those with and without LGE (26±7% vs. 28±9%, p=0.342). Conclusion The presence of LGE is a strong predictor of life threatening arrhythmias in patients in non-ischemic DCM undergoing ICD implantation for primary prevention, seemingly outperforming the clinical MADIT-ICD benefit score. Funding Acknowledgement Type of funding sources: None.

Introduction Recently, the European Society of Cardiology issued new algorithms (SCORE-2 and SCORE2-OP) to estimate the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). CACS has been shown to reclassify a significant proportion of patients when applied on top of several scores, but data on its use with these new algorithms are lacking. The aim of this study was to assess the risk reassignment that can be attained by using CACS as a risk modifier of the SCORE-2 / SCORE2-OP classification, in patients referred for coronary CT angiography (CCTA). Methods Individuals without diabetes or known ASCVD were included in a single center registry of patients undergoing CCTA for suspected coronary artery disease (CAD). The 10-year risk of cardiovascular disease was calculated for each patient using SCORE-2 (ages 40–69) or SCORE2-OP (ages 70–89), and categorised as low-to-moderate, high, or very-high risk, according to guideline-recommended age-specific thresholds. CACS was considered to reclassify risk one level downward if = 0 in high or very-high risk patients, and reclassify risk upward if >100 (or >75th percentile) in those with low-to-moderate risk, or >1000 in those with high-risk. Results A total of 529 patients (43% men, mean age 63±10 years) were included, of which 13% (n=69) were active smokers. The mean systolic blood pressure and non-HDL-C values were 137±18 mmHg and 140±37 mg/dL, respectively. A total of 47 patients (9%) had obstructive CAD on CCTA, classifying them as very-high risk. In the remainder 482 patients without obstructive CAD, the median CACS was 8 (IQR 0–80 AU), with 194 patients (40%) having CACS = 0, and 111 (23%) presenting CACS values ≥100. The proportion of patients classified as low-to-moderate risk, high risk, and very high risk was 36%, 46% and 19% using the SCORE-2 / SCORE2-OP algorithm. Using CACS would reclassify 150 patients (31%): 107 patients (22%) downward, and 43 patients (9%) upward. The extent of risk reclassification conveyed by CACS was 33% in patients assessed with SCORE-2, and 25% with SCORE-2 OP (p=0.082). Overall, most of the risk reassignment (42%, n=93) would occur in patients originally classified as high-risk – Fig. 1. At the time of testing, 32% (n=61) of patients with CACS = 0 were being treated with statins, whereas 52% (n=58) of those with CACS ≥100 were not. Conclusion Even when the most recent SCORE-2 / SCORE-2 OP algorithms are used, risk refinement with CACS leads to the reclassification of nearly one third of the patients undergoing CCTA, mostly from downgrading risk. This opportunistic use of CACS may be employed to improve the allocation of primary prevention therapies. Funding Acknowledgement Type of funding sources: None.

Background Myocardial fibrosis (MF) is a common finding and a potential adverse prognostic marker in several cardiac diseases, including in severe aortic stenosis (AS). While histological analysis obtained through endomyocardial biopsy remains the gold-standard for MF assessment, non-invasive cardiac imaging may offer surrogate biomarkers for fibrosis. We tried to assess the correlation between MF quantification at histopathology and cardiac magnetic resonance (CMR)-derived tissue characterization data in patients with severe AS. Methodology Single-center prospective cohort enrolling 71 patients with severe symptomatic high-gradient AS undergoing surgical aortic valve replacement (SAVR) (mean age 71±9 years; 49% male, mean valvular transaortic gradient 60±20 mmHg; mean left ventricle [LV] ejection fraction 58±9%). Those with past history of myocardial infarction or cardiomyopathy were excluded. All patients underwent pre-operative CMR study with LV tissue characterization and quantification. Normal T1 mapping value was defined as >1021ms as per center protocol. Myocardial tissue was obtained during SAVR either through myocardial biopsy at basal LV septum or harvested from surgical myectomy specimens. Masson's trichrome stain was used for collagen/fibrosis assessment. Automatic quantification was obtained at QuPathTM digital pathology software after applying a dedicated artificial intelligence algorithm on ultra-high-resolution digital slide scanning images. Results Histology-confirmed MF was observed in all patients (median percentage of fibrotic myocardial tissue 15% [IQR 9–22%]). Median global T1 mapping and extracellular volume (ECV) percentage was 1048ms (IQR 1027–1078) and 24% (IQR 20–30%), respectively. Late gadolinium enhancement (LGE) with a non-ischemic pattern was present in 42 patients (59%) with a median LGE mass of 5.8g [IQR 1.0–10.2]; median percentage of 3.7% [IQR 0.6–10.4]. While neither T1 mapping (global or basal LV septum), ECV nor LGE had any significant correlation with histology-confirmed MF (Figure 1) the vast majority had significantly elevated global and basal LV septum T1 mapping – 81% and 92%, respectively. Conclusion In this single-center prospective study, microscopic MF was present in all patients with severe symptomatic high-gradient AS, was accompanied by elevated T1 mapping values but no correlation was found between myocardial fibrosis at histopathology analysis and CMR-derived LV tissue characterization parameters. This may not only stem from sampling (single point biopsy vs. whole myocardial tissue assessment) but also from distinct evaluation of different types of fibrosis by different methods. Funding Acknowledgement Type of funding sources: None.

Background Relative apical sparing (RAS) of left ventricular (LV) longitudinal strain (LS) is a red flag marker for the suspicion of amyloid cardiomyopathy. However, it has also been described in patients with severe aortic stenosis (AS). Aim To assess the prevalence of RAS in patients with severe symptomatic AS referred for surgical aortic valve replacement (AVR), to evaluate its clinical significance and assess its presence after surgery. Methods We prospectively studied 135 consecutive patients (age: 73 y [IQR 68–77 y], 49% men) with severe symptomatic AS – mean transaortic pressure gradient (AVmean): 60.9±17.7 mmHg; mean aortic valve area: 0.7±0.2 cm2, referred for surgical AVR with no previous history of ischemic cardiomyopathy or other. Beyond 12 lead-ECG and transthoracic echocardiography (TTE), all patients underwent cardiac magnetic resonance (CMR) before surgery. RAS was defined by the ratio >1 of average LS at apical segments/sum of the average basal and mid LS at speckle tracking analysis. AVR with septal myocardial biopsy, for investigational purposes, was performed in 80 patients. AS severity indexes, LV remodeling and tissue characterization parameters were compared in both groups of patients, with and without RAS. LS deformation pattern was reassessed at 3–6 months after AVR. Results RAS was present in 24 patients (18%). In the whole cohort there were neither pseudoinfarct pattern or low voltage ECG criteria, nor infiltration suspicion from CMR (native T1 value 1053 ms [IQR 1025–1071 ms] for institutional reference values: 972–1070 ms; ECV 24% [IQR 21–27%]). None of the patients had amyloid deposition at histopathology. Overall, mean CMR LV ejection fraction (LVEF) was 59.6±10.5% and 98 patients (74%) had non-ischemic delayed enhancement, with a median fibrosis fraction of 4.1% [IQR 1.6–7.8%]. RAS cohort had a significantly higher AVmean gradient, relative wall thickness, maximum septal thickness, peak systolic dispersion, with lower global LS at TTE, as well as higher LV mass and lower LVEF at CMR. RAS group has also higher NT-proBNP ambulatory values (Table 1). Follow-up evaluation after AVR revealed RAS disappearance in 19 patients (79.2%). Conclusions RAS occurs in almost one-fifth of the patients in this cohort despite the absence of signs of myocardial infiltration. This deformation pattern elapses with worse indexes of LV remodeling consistent with a more advanced stage of the disease, being reversible after AVR, which stands for the absence of concomitant myocardial infiltration. Funding Acknowledgement Type of funding sources: None.

Background Chemotherapy-induced cardiotoxicity is a serious complication often leading to heart failure. While the left ventricle (LV) has been thoroughly implicated in this process, data is scarce on right ventricular (RV) function following cardiotoxic chemotherapies. Our goal was to determine the prevalence and clinical significance of RV dysfunction in a cohort of patients who had received these drugs. Methodology Single-center retrospective study of cancer patients performing 2D transthoracic echocardiogram between January 2020 and December 2021. Those previously exposed to anthracyclines and/or anti-HER2 agents (≥6 months prior to echocardiogram) were included. Patients with known coronary artery disease or cardiomyopathy were excluded. LV function was assessed through LV ejection fraction (LVEF) and global longitudinal strain (GLS). LV cardiotoxicity was defined as per 2020 ESMO guidelines. RV function was considered abnormal if the following criteria were met: tricuspid annular plane systolic excursion (TAPSE) −20%. Results Forty patients were included (58±13 years; 95% female; 93% with breast cancer; 30%, 20% and 50% previously treated with anthracyclines, anti-HER2 or both, respectively). Mean LVEF and GLS were 56±7% and −17±3%. Overall, 13 patients had current LV cardiotoxicity. RV dysfunction was documented in 15 (38%) patients (7 [18%] with isolated RV dysfunction), most often detected through FWLS (14 [35%], 7 [18%], 6 [15%] and 5 [13%] patients with abnormal FWLS, TAPSE, FAC and S'VD, respectively) – Figure 1. Seven patients (18%) and one patient (3%) had ≥2 and ≥3 abnormal RV parameters. Those with RV dysfunction were more often symptomatic (NYHA class ≥2: 53% vs. 16%; p=0.013), had higher NT-proBNP levels (516 [204–2400] vs. 66 [46–191] pg/mL; p=0.003) and most often had LV cardiotoxicity (62% vs. 26%, p=0.029); pulmonary artery systolic pressures were similar between both groups. Conclusion In our cohort of patients treated with cardiotoxic anti-neoplastic drugs, RV dysfunction was observed in two out of every five patients, most often detected by RV 2D strain and associated with worse symptoms and higher NT-proBNP levels. This data suggests that RV cardiotoxicity may be common and clinically impactful in those under cardiotoxic chemotherapies. Funding Acknowledgement Type of funding sources: None.

Background Cardiac magnetic resonance (CMR) is recommended in Heart Failure (HF) to assess myocardial structure and function. Recently, the quantification of pulmonary congestion and skeletal muscle mass using CMR have been shown to predict adverse events in HF, but a tool integrating this information is currently unavailable. The purpose of this study was to develop and test a new multiparametric CMR-derived score. Methods We conducted a single-center retrospective study of consecutive HF patients with left ventricular ejection fraction (LVEF) Results Overall, 436 patients were included. During a median follow-up of 27 (17–37) months, 43 (9.9%) patients died and 57 (13.2%) had at least one hospitalization for HF. LVEF, LWD and PMM were independent predictors of the primary endpoint and were included in the CMR-HF score – Figure 2. The annual rate of events increased from 4.7 to 7.5 and 20.0% from lowest to highest tertile of the score. Roughly half of the events (54%) occurred in patients in the highest tertile of the CMR-HF score. In multivariate analysis, the new score independently predicted the primary endpoint (HR per 5 points: 1.54; 95% CI: 1.21–1.97; p Conclusions This novel multidimensional CMR-HF score, combining easily obtainable data on left ventricular pump failure, lung congestion and muscular wasting, is a promising tool identifying HF patients with an LVEF Funding Acknowledgement Type of funding sources: None.

Objectives Tuberculosis (TB) is the most common opportunistic infection and cause of mortality among people living with HIV, and it is possible that it may also influence the evolution of the HIV infection. We assessed the differences between HIV-positive and -negative people infected with TB. Methods The present study is a cross-sectional retrospective study by electronic record revision. We included patients admitted to a tertiary hospital with a diagnosis of TB between 2011 and 2016, comparing those with HIV coinfection with non-HIV patients, according to demographic and clinical characteristics. Results This study included 591 patients, of whom 32% were HIV-coinfected. HIV-TB patients were younger, with a predominance of male gender. Considering TB risk factors, there was a higher prevalence of homelessness and intravenous drug use in the HIV group. In the non-HIV group, direct contact with other patients with TB and immunosuppression were more prevalent. Relative to TB characteristics, the HIV-coinfected group presents with a higher prevalence of disseminated disease and a higher occurrence of previous TB infection. Cancer was the most frequent cause of immunosuppression in the HIV group and the number testing positive for TB via microbiological culture was lower. Assessment of microbiological resistance and in-hospital mortality showed similar numbers in both groups. Conclusions There are few papers comparing clinical course of TB between HIV-infected and non-infected patients. Our study differs from others in the literature as we focused on a country with middling incidence of TB and further characterized the differences between HIV-infected and non-infected patients which can contribute to the management of these patients.

Funding Acknowledgements Type of funding sources: None. Background Current sudden cardiac death (SCD) risk stratification relies heavily on left ventricular ejection fraction (LVEF), but markers to refine risk assessment are needed. Dense core fibrosis (DCF) and peri-infarct "gray zone" of myocardial fibrosis (GZF) on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) have been proposed as potential arrhythmogenic substrates. The aim of our study was to determine whether DCF and GZF could predict the occurrence of ventricular arrhythmias in patients with previous myocardial infarction. Methods We performed a single centre retrospective study enrolling consecutive patients with previous myocardial infarction undergoing CMR before implantable cardioverter-defibrillator (ICD) implantation. Areas of LGE were subdivided into "core" DCF and "peri-infarct" GZF zones based on signal intensity (>5 SD, and 2-5 SD above the mean of reference myocardium, respectively). The primary endpoint was a composite of sudden arrhythmic death, appropriate ICD shock, ventricular fibrillation (VF), or sustained ventricular tachycardia (VT) as detected by the device. Results A total of 88 patients (median age 61 years [IQR 54-73], 84% male, median LVEF 30% [IQR 23-36%], 14% secondary prevention) were included. During a median follow-up of 23 months [IQR 9-38], 13 patients reached the primary endpoint (10 appropriate ICD shock, 2 sustained VT or VF, and 1 sudden arrhythmic death). Patients who attained the primary endpoint had similar DCF (30.4g ± 14.7 vs. 28.0g ± 15.3; P = 0.601) but a greater amount of GZF (18.1g ± 9.6 vs. 11.9g ± 6.7; P = 0.005). On univariate analysis, GZF was associated with the composite endpoint (HR: 1.09 per gram; 95%CI: 1.02-1.15; P = 0.006), whereas DCF was not (HR: 1.01 per gram; 95%CI: 0.98-1.05; P = 0.571). After adjustment for LVEF, GZF remained independently associated with the primary endpoint (adjusted HR: 1.06 per gram; 95% CI: 1.01-1.12; P = 0.035). Decision tree analysis identified 11.9g of GZF as the best cut-off to predict life-threatening arrhythmic events. The primary endpoint occurred in 11 out of the 35 patients (31.4%) with GZF ≥11.9g, but in only 2 of the 53 patients (3.8%) with GZF Conclusions The extent of peri-infarct GZF seems to be a better predictor of ventricular arrhythmias than DCF. This parameter may be useful to identify a subgroup of patients with previous myocardial infarction at increased risk of life-threatening arrhythmic events.

Funding Acknowledgements Type of funding sources: None. Introduction Recently, a classification with four types of septal longitudinal strain patterns was described using a speckle tracking based strain analysis in echocardiography suggesting pathophysiological continuum of LBBB-induced LV remodeling. Little data exist on feature tracking cardiac magnetic resonance (FT-CMR) in LBBB patients, and whether such patterns could be reproduced in CMR is not established yet. Purpose In this study, we aimed to: 1) Assess and reproduce the new strain patterns classification by CMR and 2) Evaluate its association with LV remodeling and myocardial scar in a LBBB cohort. Methods Single center registry which included LBBB patients with septal flash (SF) referred to CMR to assess the structural cause of LV dysfunction. LBBB was defined according to Strauss criteria as strict LBBB, non-strict LBBB or nonspecific LV conduction delay. A semi-automated FT-CMR was used to quantify myocardial strain and detect the four septal longitudinal and radial strain patterns, according to the recent classification (LBBB-1 through LBBB-4) – Figure. Extent of SF was visually scored as mild, moderate, or prominent. Results A total of 115 patients were included (mean age 66±11 years; 57% men; 38% with ischemic heart disease). Median duration of QRS was 150± 26ms and majority of the patients (n=90, 78%) were classified as strict LBBB. In longitudinal strain analyses LBBB-1 was observed in 23 (20%), LBBB-2 in 37 (32.1%), LBBB-3 in 25 (21.7%), and LBBB-4 in 30 (26%) patients. Patients at higher LBBB stages (longitudinal or radial pattern) had more prominent septal flash, greater LV volumes, lower LV ejection fraction and lower absolute global longitudinal, circumferential and radial strain values compared with patients in less advanced stages (p < 0.05 for all) - table. There was no difference between patterns in clinical characteristics, ischemic etiology, QRS duration and time delay between septal and lateral LV wall. Late gadolinium enhancement (LGE) was found in 63 patients (54.8%), with a septal location in 34 (29.6%) patients, lateral in 4 (3.5%) patients, septal and lateral in 11 (9.6%) patients. Furthermore, no difference was found for LGE presence, distribution or location between the four strain patterns. Conclusions Among patients with LBBB, our study found a good association between longitudinal and radial strain patterns with the degree of LV remodeling and LV dysfunction by FT-CMR analysis. Additionally, myocardial fibrosis didn’t seem to interfere with the staged LBBB classification.

The present study analyses the first data on genetic diversity of A. quebracho-blanco with the fragmentation of its natural habitat, supporting conservation strategies such as the definition of priority areas for conservation. DNA was extracted from 25 individuals of five populations of A. quebracho-blanco from Argentina, Paraguay, and Brazil. Six ISSR primers were used to characterize the genetic diversity and structure of this species. The genotypes were grouped according to a distance matrix, considering the genetic diversity indices of Nei (He), Shannon (H’), polymorphic information content (PIC), and heterozygosis (H). The populations showed an average genetic diversity that ranged from 0.09 to 0.15 for the Shannon index and from 0.19 to 0.31 for the Nei index; the Mantel test was not significant (r2 = 0.25, P = 0.106). The results obteined for the sampled populations reveal that conservation units are indispensable for conserving the species genetic resources. In addition, it would be essential to construct a germplasm bank for the Cordoba (Argentina) population, which is a population with high genetic diversity in a region of lower fragmentation compared to other regions evaluated, to ensure the conservation of A. quebracho-blanco.

Epithelial-to-mesenchymal transition (EMT) has been associated with cancer cell heterogeneity, plasticity, and metastasis. However, the extrinsic signals supervising these phenotypic transitions remain elusive. To assess how selected microenvironmental signals control cancer-associated phenotypes along the EMT continuum, we defined a logical model of the EMT cellular network that yields qualitative degrees of cell adhesions by adherens junctions and focal adhesions, two features affected during EMT. The model attractors recovered epithelial, mesenchymal, and hybrid phenotypes. Simulations showed that hybrid phenotypes may arise through independent molecular paths involving stringent extrinsic signals. Of particular interest, model predictions and their experimental validations indicated that: (i) stiffening of the extracellular matrix was a prerequisite for cells overactivating FAK_SRC to upregulate SNAIL and acquire a mesenchymal phenotype and (ii) FAK_SRC inhibition of cell–cell contacts through the receptor-type tyrosine-protein phosphatases kappa led to acquisition of a full mesenchymal, rather than a hybrid, phenotype. Altogether, these computational and experimental approaches allow assessment of critical microenvironmental signals controlling hybrid EMT phenotypes and indicate that EMT involves multiple molecular programs. Significance: A multidisciplinary study sheds light on microenvironmental signals controlling cancer cell plasticity along EMT and suggests that hybrid and mesenchymal phenotypes arise through independent molecular paths.

Alterations in the expression or function of cell adhesion molecules have been implicated in all steps of tumour progression. Among those, P-cadherin expression is highly enriched in basal-like breast cancer, a molecular subset of triple-negative breast carcinomas, playing a central role in inducing cancer cell self-renewal, as well as collective cell migration and invasion capacity. To decipher the P-cadherin-dependent signalling network, we generated a humanised P-cadherin fly model, establishing a clinically relevant platform for functional exploration of P-cadherin effectors in vivo. We report that actin nucleators, MRTF and SRF are main effectors of P-cadherin functional effects. In addition, we validated these findings in a human mammary epithelial cell line with conditional activation of the Src oncogene, which recapitulates molecular events taking place during cellular transformation. We show that prior to triggering the gain of malignant phenotypes, Src induces a transient increase in P-cadherin expression levels, which correlates with MRTF-A accumulation, its nuclear translocation and the upregulation of SRF target genes. Moreover, knocking down P-cadherin, or preventing Factin polymerization with Latrunculin A, impairs SRF transcriptional activity. Furthermore, blocking MRTF-A nuclear translocation with CCG-203971 hampers proliferation, selfrenewal and invasion. Thus, in addition to sustaining malignant phenotypes, P-cadherin can also play a major role in the very early stages of breast carcinogenesis by promoting a transient boost of MRTF-A/SRF signalling through actin regulation.

Funding Acknowledgements Type of funding sources: None. Background Chronic mitral regurgitation has been shown to promote left atrial (LA) dysfunction and remodeling. However, the significance of LA dysfunction in this setting has not been fully investigated. The aim of our study was to assess the prognostic impact of peak atrial longitudinal strain (PALS), a surrogate of LA function, in a cohort of patients with LV systolic dysfunction and functional mitral regurgitation (FMR). Methods Patients with at least mild FMR and reduced LVEF (< 50%) under optimized medical therapy who underwent transthoracic echocardiography between 2010 and 2018 were retrospectively identified at a single-centre. FMR grading was undertaken according to the new 2021 valvular guidelines. PALS was assessed by 2D speckle tracking in apical 4-chamber view (as per EACVI current recommendations). Cox proportional hazards regression was applied for univariable and multivariable analysis to investigate the association between clinical and echocardiographic parameters, namely PALS, and all-cause mortality. Results A total of 307 patients (median age 70 years, 77% male) were included. Median LVEF was 35% (IQR: 27 – 40%) and median mitral regurgitant volume was 25mL (IQR: 14 – 34mL). According to the new ESC 2021 valvular guidelines, 32 patients had severe FMR (10%). During a median follow-up of 3.5 years (IQR 1.4 – 6.6), 148 patients died. Median PALS was 14% (IQR 8 – 20%). The unadjusted mortality incidence per 100 persons-years increased with progressively lower values of PALS (figure 1). On ROC curve analysis, the best PALS cut-off value associated with mortality was < 15%. Kaplan-Meier survival curves according to FMR severity and PALS > or < 15% are depicted in figure 2. PALS remained independently associated with all-cause mortality on multivariable analysis (adjusted hazard ratio [aHR]: 0.94; 95%CI: 0.90 – 0.98; p = 0.004) even after adjustment for several (n = 14) clinical and echocardiographic confounders. Conclusion In a cohort of patients with reduced LVEF and functional mitral regurgitation, peak atrial longitudinal strain was associated with all-cause mortality. Abstract Figure 1 Abstract Figure 2

Background Left ventricular myocardial work (LVMW) is a novel method to evaluated left ventricular (LV) function using pressure-strain loops. It might correct global longitudinal strain (GLS) for afterload, being eventually useful to assess whether GLS reduction is due to reduced contractility (reflected as reduced myocardial work) or increased afterload (reflected as increased myocardial work). Aim To describe indices of LVMW in a group of patients with severe symptomatic aortic stenosis (AS). Methods We prospectively studied 104 consecutive patients (age: 71 years [IQR 66.5–75.5] years, 51% men) with severe symptomatic high gradient AS: mean transaortic pressure gradient: 56.5mmHg [IQR 46.8–67.8]; aortic valve area: 0.73cm2 [IQR 0.61–0.88]; indexed stroke volume: 47.7±1.3 mL/m2 (11 patients with low-flow AS), preserved LV ejection fraction (EV) (LVEF: 56.0% [51.0–61.3]; GLS: −14.5% [IQR −16.1 to −10.6]), with no previous coronary artery disease and no history of cardiomyopathy. Beyond complete transthoracic echocardiography, all patients underwent cardiac magnetic resonance for LV myocardium tissue characterization. As proposed for AS, LV systolic pressure was corrected adding the mean transaortic pressure gradient to non-invasive systolic blood pressure cuff measurement in the echocardiographic algorithm. Four LVMW indices were collected in 83 patients (patients excluded for atrial fibrillation, left bundle branch block or absence of non-invasive blood pressure registration) and correlated to LV function indexes, LV hypertrophy and remodeling, myocardial tissue characterization, BNP and troponin levels (Pearson or Spearman correlation). These same indexes were compared in patients with LV ejection fraction (EF) below and above 50%, normal and reduced flow and presence of replacement fibrosis. Results Global constructive work (GCW) (2658.6±76.4mmHg%), global myocardial work (GMW) (2218.7±74.9mmHg%) and global wasted work (GWE) (262.0mmHg% [198.8–339.5]) were high above normal with concomitant lower work efficiency (WE) (88.0% [83.2–91.8]. Weak correlations were found between LVMW indexes and parameters describing aortic valve severity, flow and LV function (table). Except for significant differences of LVMI in patients with reduced LV ejection fraction (GCW 2770.3±687.4 vs 2056.0±380.7mmHg%, p=0,014 and GMW 2362.5±657.9 vs 1621.3±319.9, p=0,021 in patients with LV EF>50% vs. LV EF Conclusions Global constructive and myocardial work are increased in these patients with severe aortic stenosis. This might reflect an increased afterload predominance rather than a LV functional impairment, particularly relevant in this group of patients with exclusive high gradient disease and preserved LVEF. Funding Acknowledgement Type of funding sources: None. Correlations between LVMI – LV function