5 research outputs found
The European Low Frequency Survey
In this paper we present the European Low Frequency Survey (ELFS), a project that will enable the detection of primordial B-mode polarization by measuring the Galactic and extra-Galactic foregrounds in the 5– 120 GHz frequency window. Indeed, the main difficulty in measuring the Bmode polarization comes not just from its sheer faintness, but from the fact that many other objects in the Universe also emit polarized microwaves, which mask the faint CMB signal. The first stage of this project will be carried out in synergy with the Simons Array (SA) collaboration, installing a 5.5–11 GHz coherent receiver at the focus of one of the three 3.5m SA telescopes in Atacama, Chile (“ELFS on SA”). The receiver will be equipped with a fully digital backend based on the latest Xilinx RF System-on-Chip devices that will provide frequency resolution of 1MHz across the whole observing band, allowing us to clean the scientific signal from unwanted radio frequency interference, particularly from low-Earth orbit satellite mega-constellations. This paper reviews the scientific motivation for ELFS and its instrumental characteristics, and provides an update on the development of ELFS on SA
High-risk percutaneous coronary intervention using hemodynamic support device eight years after transcatheter aortic valve implantation
Coronary artery disease is a frequent comorbidity in patients with severe aortic stenosis undergoing trans-catheter aortic valve implantation (TAVI) and the need to ensure coronary access after TAVI is fundamental. This aspect is becoming increasingly relevant as TAVI indication expand to younger and lower-risk patients. Moreover, the longer life expectancy of subjects who are currently treated with TAVI could result in an increased need for TAVI-in-TAVI due to valve degeneration. As the implantation of a second transcatheter bioprosthesis might impair coronary access, TAVI-in-TAVI will be unfeasible in a significant proportion of cases, particularly if they received a tall-frame transcatheter heart valve at the time of the first intervention. Thus, patients might experience the paradox of needing surgical aortic valve replacement when they are older and frailer. Here we report the case of a patient with history of coronary artery disease and severe aortic stenosis treated with TAVI, presenting with an acute coronary syndrome 8 years after percutaneous aortic valve implantation. Thanks to the low frame height of the transcatheter aortic valve, it was possible to easily perform coronary angiography and high-risk percutaneous coronary intervention using hemodynamic support device (Impella CP). Moreover, this case highlights how the implantation of a low-frame transcatheter prosthesis can increase the possibility of achieving coronary access even after TAVI-in-TAVI, if needed
Impact of the “atherosclerotic pabulum” on in-hospital mortality for SARS-CoV-2 infection. Is calcium score able to identify at-risk patients?
Background: Although the primary cause of death in COVID-19 infection is respiratory failure, there is evidence that cardiac manifestations may contribute to overall mortality and can even be the primary cause of death. More importantly, it is recognized that COVID-19 is associated with a high incidence of thrombotic complications. Hypothesis: Evaluate if the coronary artery calcium (CAC) score was useful to predict in-hospital (in-H) mortality in patients with COVID-19. Secondary end-points were needed for mechanical ventilation and intensive care unit admission. Methods: Two-hundred eighty-four patients (63, 25 years, 67% male) with proven severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who had a noncontrast chest computed tomography were analyzed for CAC score. Clinical and radiological data were retrieved. Results: Patients with CAC had a higher inflammatory burden at admission (d-dimer, p =.002; C-reactive protein, p =.002; procalcitonin, p =.016) and a higher high-sensitive cardiac troponin I (HScTnI, p = 200 ng/dl was a better determinant of all outcomes in both univariate (p = <.001) and multivariate analysis (p = <.001). Conclusion: The main finding of our research is that CAC was positively related to in-H mortality, but it did not completely identify all the population at risk of events in the setting of COVID-19 patients. This raises the possibility that other factors, including the presence of soft, unstable plaques, may have a role in adverse outcomes in SARS-CoV-2 infection
Coronary Access After Transcatheter Aortic Valve Replacement With Commissural Alignment: The ALIGN-ACCESS Study
BACKGROUND: Coronary access (CA) after transcatheter aortic valve replacement (TAVR) with supra-annular transcatheter heart valves (THV) can be challenging. Specific Evolut R/Pro and Acurate Neo THVs orientations are associated with reduced neo-commissure overlap with coronary ostia, while SAPIEN 3 THV cannot be oriented. With the ALIGN-ACCESS study (TAVR With Commissural Alignment Followed by Coronary Access), we investigated the impact of commissural alignment on the feasibility of CA after TAVR. METHODS: We performed coronary angiography after TAVR with intra-annular SAPIEN 3, supra-annular Evolut R/Pro, and Acurate Neo THVs in 206 patients. Evolut THVs were implanted aiming for commissure alignment. Alignment of Acurate Neo was retrospectively assessed in 36, intentionally attempted in 26 cases. The primary end point was the rate of unfeasible and nonselective CA after TAVR. RESULTS: Thirty-eight percent of patients received SAPIEN 3, 31.1% Evolut Pro/R, 30.1% Acurate Neo THV. Final valve orientation was favorable to commissural alignment in 85.9% of Evolut and 69.4% of Acurate Neo cases (with intentional alignment successful in 88.5%). Selective CA was higher for SAPIEN 3 than for aligned and misaligned supra-annular THVs (95% versus 71% versus 46%, P<0.001). Cannulation of at least one coronary was unfeasible with 11% misaligned supra-annular, 3% aligned supra-annular, and 0% SAPIEN 3 THVs. Independent predictors of unfeasible/nonselective CA were implantation of a misaligned supra-annular THV (odds ratio, 4.59 [95% CI, 1.81-11.61]; P<0.01), sinus of Valsalva height (odds ratio, 0.83 [95% CI, 0.7-0.98]; P=0.03), and THV-sinus of Valsalva relation (odds ratio, 1.06 [95% CI, 1.02-1.1]; P<0.01). CONCLUSIONS: Commissural alignment improves the rate of selective CA after TAVR with supra-annular THVs. Nevertheless, aligned supra-annular THVs carry higher risk of unfeasible/nonselective CA than SAPIEN 3. Patients with a misaligned supra-annular THV, low sinus of Valsalva, and higher THV-sinus of Valsalva relation are at highest risk of impaired CA after TAVR
Prevalence of Abdominal Aortic Aneurysms in the General Population and in Subgroups at High Cardiovascular Risk in Italy. Results of the RoCAV Population Based Study
Objectives: Prevalence data on abdominal aortic aneurysm (AAA) in women, subjects younger than 65 years and in subgroups carrying specific risk factors are scarce. AAA prevalence was evaluated in an Italian population including women and younger subjects, stratifying for the presence of cardiovascular disease (CVD) risk factors and CVD risk score. Materials and methods: A population based cross-sectional study was conducted between 2013 and 2016. Men aged 50-75 and women aged 60-75 years, resident in the city of Varese (northern Italy), were randomly selected from the civil registry. A vascular surgeon performed an abdominal aortic ultrasound scan at four sites using the leading edge to leading edge method. CVD risk score was computed using the ESC-SCORE algorithm. The age and gender specific prevalence was estimated, stratifying by the presence of CVD and cardiovascular risk factors. Results: Among the 3755 subjects with a valid ultrasound measurement, 63 subjects with an AAA were identified (5 referred for surgical intervention), among whom 34 were not previously known (30 men 1.3%, 95% CI 0.9-1.8; 4 women 0.3%, 95% CI 0.1-0.8). Considering age classes in men only, the highest prevalence of screen detected AAA was found in subjects aged 65-70 (1.2%; 95% CI 0.4-2.5) and 70-75 (2.5%; 95% CI 1.4-4.0) years. Among 65-75 year old men, the highest AAA prevalence was found in subjects with a previous myocardial infarction (MI 4.9%, 95% CI 2.0-9.9) and in ever-smokers reporting more than 15 pack years of smoking (4.1%, 95% CI 2.5-6.3). Among the younger subjects, those having an ESC-SCORE higher than 5% or a previous CVD (MI or stroke) showed a prevalence of 1.4% (95% CI 0.3-4.2; prevalence including subaneurysms 6.7%, 95% CI 3.7-11.0%). Conclusions: In the study population, both a general screening program in 65-75 year old men and an approach targeted to subgroups at higher risk merit evaluation in a cost-effectiveness study. In 50-64 year old men, strategies for population selection should consider CVD risk stratification tools