Abstract Background Pre-clinical trials have demonstrated that, during intravenous microbubble infusion, high mechanical index (HMI) impulses from a diagnostic ultrasound (DUS) transducer might ...restore epicardial and microvascular flow in acute ST-segment elevation myocardial infarction (STEMI). Objectives The purpose of this study was to test the safety and efficacy of this adjunctive approach in humans. Methods From May 2014 through September 2015, patients arriving with their first STEMI were randomized to either DUS intermittent HMI impulses (n = 20) just prior to emergent percutaneous coronary intervention (PCI) and for an additional 30 min post-PCI (HMI + PCI), or low mechanical index (LMI) imaging only (n = 10) for perfusion assessments before and after PCI (LMI + PCI). All studies were conducted during an intravenous perflutren lipid microsphere infusion. A control reference group (n = 70) arrived outside of the time window of ultrasound availability and received emergent PCI alone (PCI only). Initial epicardial recanalization rates prior to emergent PCI and improvements in microvascular flow were compared between ultrasound-treated groups. Results Median door-to-dilation times were 82 ± 26 min in the LMI + PCI group, 72 ± 15 min in the HMI + PCI group, and 103 ± 42 min in the PCI-only group (p = NS). Angiographic recanalization prior to PCI was seen in 12 of 20 HMI + PCI patients (60%) compared with 10% of LMI + PCI and 23% of PCI-only patients (p = 0.002). There were no differences in microvascular obstructed segments prior to treatment, but there were significantly smaller proportions of obstructed segments in the HMI + PCI group at 1 month (p = 0.001) and significant improvements in left ventricular ejection fraction (p < 0.005). Conclusions HMI impulses from a diagnostic transducer, combined with a commercial microbubble infusion, can prevent microvascular obstruction and improve functional outcome when added to the contemporary PCI management of acute STEMI. (Therapeutic Use of Ultrasound in Acute Coronary Artery Disease; NCT02410330 )
Preclinical studies have demonstrated that high mechanical index (MI) impulses from a diagnostic ultrasound transducer during an intravenous microbubble infusion (sonothrombolysis) can restore ...epicardial and microvascular flow in acute ST-segment elevation myocardial infarction (STEMI).
This study tested the clinical effectiveness of sonothrombolysis in patients with STEMI.
Patients with their first STEMI were prospectively randomized to either diagnostic ultrasound–guided high MI impulses during an intravenous Definity (Lantheus Medical Imaging, North Billerica, Massachusetts) infusion before, and following, emergent percutaneous coronary intervention (PCI), or to a control group that received PCI only (n = 50 in each group). A reference first STEMI group (n = 203) who arrived outside the randomization window was also analyzed. Angiographic recanalization before PCI, ST-segment resolution, infarct size by magnetic resonance imaging, and systolic function (LVEF) at 6 months were compared.
ST-segment resolution occurred in 16 (32%) high MI PCI versus 2 (4%) PCI-only patients before PCI, and angiographic recanalization was 48% in high MI/PCI versus 20% in PCI only and 21% in the reference group (p < 0.001). Infarct size was reduced (29 ± 22 g high MI/PCI vs. 40 ± 20 g PCI only; p = 0.026). LVEF was not different between groups before treatment (44 ± 11% vs. 43 ± 10%), but increased immediately after PCI in the high MI/PCI group (p = 0.03), and remained higher at 6 months (p = 0.015). Need for implantable defibrillator (LVEF ≤30%) was reduced in the high MI/PCI group (5% vs. 18% PCI only; p = 0.045).
Sonothrombolysis added to PCI improves recanalization rates and reduces infarct size, resulting in sustained improvements in systolic function after STEMI. (Therapeutic Use of Ultrasound in Acute Coronary Artery Disease; NCT02410330).
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Abstract
The main purpose of this study is to review the Schenberg resonant antenna transfer function and to recalculate the antenna design strain sensitivity for gravitational waves. We consider the ...spherical antenna with six transducers in the semi dodecahedral configuration. When coupled to the antenna, the transducer-sphere system will work as a mass-spring system with three masses. The first one is the antenna effective mass for each quadrupole mode, the second one is the mass of the mechanical structure of the transducer first mechanical mode and the third one is the effective mass of the transducer membrane that makes one of the transducer microwave cavity walls. All the calculations are done for the degenerate (all the sphere quadrupole mode frequencies equal) and non-degenerate sphere cases. We have come to the conclusion that the “ultimate” sensitivity of an advanced version of Schenberg antenna (aSchenberg) is around the standard quantum limit (although the parametric transducers used could, in principle, surpass this limit). However, this sensitivity, in the frequency range where Schenberg operates, has already been achieved by the two aLIGOs in the O3 run, therefore, the only reasonable justification for remounting the Schenberg antenna and trying to place it in the sensitivity of the standard quantum limit would be to detect gravitational waves with another physical principle, different from the one used by laser interferometers. This other physical principle would be the absorption of the gravitational wave energy by a resonant mass like Schenberg.
Abstract
Background
Information is lacking concerning in-hospital echocardiography analysis of COVID-19 infection in Brazil. We evaluated echocardiographic parameters to predict a composite endpoint ...of mortality, pulmonary thromboembolism or acute renal failure.
Methods
A prospective full echocardiographic study of consecutive patients hospitalized with COVID-19, single tertiary centre in Brazil. We correlated echocardiographic findings to biomarkers, clinical information, thoracic tomography, and in-hospital composite endpoint of mortality, pulmonary thromboembolism or renal failure.
Results
One hundred eleven patients from March to October 2020, 67 ± 17 years, 65 (58.5%) men, death was observed in 21/111 (18.9%) patients, 48 (43%) required mechanical ventilation, myocardial infarction occurred in 10 (9%), pulmonary thromboembolism in 7 (6.3%) patients, haemodialysis was required for 9 (9.8%). Echocardiography was normal in 51 (46%) patients, 20 (18%) presented with decreased left ventricle ejection, 18 (16.2%) had abnormal left ventricle global longitudinal strain, 35 (31%) had diastolic dysfunction, 6 (5.4%) had an E/e’ratio > 14, 19 (17.1%) presented with right ventricle dilated/dysfunction, 31 (28%) had pericardial effusion. The echocardiographic parameters did not correlate with mortality, biomarkers, clinical events. Tricuspid velocity was related to the composite endpoint of mortality, pulmonary thromboembolism or acute renal failure (
p
: 00.3; value: 2.65 m/s; AUC ROC curve: 0.739; sensitivity: 73.3; specificity: 66.7; CI: 0.95, inferior: 0.613; superior: 0,866).
Conclusions
Among hospitalized patients with COVID-19, echocardiography was normal in 51(46%) patients, and 20 (18%) patients presented with a decreased left ventricle ejection fraction. Tricuspid velocity was related to the composite endpoint of mortality, pulmonary thromboembolism or acute renal failure.
The diagnostic ultrasound-guided high mechanical index impulses during an intravenous microbubble infusion (sonothrombolysis) improve myocardial perfusion in acute ST segment elevation myocardial ...infarction, but its effect on left ventricular diastolic dysfunction (DD), left atrial (LA) mechanics and remodeling is unknown. We assessed the effect of sonothrombolysis on DD grade and LA mechanics.
One hundred patients (59 ± 10 years; 34% women) were randomized to receive either high mechanical index impulses plus percutaneous coronary intervention (PCI) (therapy group) or PCI only (control group) (n = 50 in each group). Diastolic dysfunction grade and LA mechanics were assessed immediately before and after PCI and at 48 to 72 hours, 1 month, and 6 months of follow-up. Diastolic dysfunction grades were classified as grades I, II, and III. The LA mechanics was obtained by two-dimensional speckle-tracking echocardiography-derived global longitudinal strain (GLS).
As follow-up time progressed, increased DD grade was observed more frequently in the control group than in the therapy group at 1 month and 6 months of follow-up (all P < .05). The LA-GLS values were incrementally higher in the therapy group when compared with the control group at 48 to 72 hours, 24.0% ± 7.3% in the therapy group versus 19.6% ± 7.2% in the control group, P = .005; at 1 month, 25.3% ± 6.3% in the therapy group versus 21.5% ± 8.3% in the control group, P = .020; and at 6 months, 26.2% ± 8.7% in the therapy group versus 21.6% ± 8.5% in the control group, P = .015. The therapy group was less likely to experience LA remodeling (odds ratio, 2.91 1.10-7.73; P = .03). LA-GLS was the sole predictor of LA remodeling (odds ratio, 0.79 0.67-0.94; P = .006).
Sonothrombolysis is associated with better DD grade and LA mechanics, reducing LA remodeling.
Agricultural growth is essential for both alleviating poverty and feeding the population of the Brazilian Amazonian periphery, where slash-and-burn agriculture continues to support the livelihoods of ...between 3.5 and 4 million people. We developed a new integrated-crop-livestock-system named “
no-till in alley cropping using leguminous tree mulch
” in partnership with local communities, to replace shifting cultivation in the region. Although such technologies have proven their agronomic efficiency, they must also meet farmers’ needs. Therefore, this study aimed to capture farmers’ perceptions about how the new technology compares with conventional agricultural systems with a view to identifying barriers to the adoption of the new system. Our results indicated low levels of resistance by farmers to the new integrated-crop-livestock-system although we identified a lack of knowledge about sustainable soil management approaches like no-till systems. From an adoption point of view, this might indicate that farmers found the new technology rather complex compared to slash-and-burn and did not fully understand that it contributed to sustainable soil management. In addition, the cost of deploying the new technology was found to be a critical barrier, mainly because agricultural activity is closely linked to family-based food consumption, rather than quality improvement and value-added for sale. We concluded that there is an opportunity to replace shifting cultivation by sustainable agricultural intensification in the humid tropics. This new approach may help to overcome weaknesses which have prevented farmers from taking advantage of available ecosystem services in regions dominated by shifting cultivation such as the Brazilian Amazonian periphery.
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