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The heterogeneous microstructure of a laser 3D printed Ni-based superalloy was examined at multiple length scales. The sub-millimeter-sized columnar crystal grains are composed of micron-sized cellular colonies. The crystal grains grow in epitaxy with the substrate under the large temperature gradient and high cooling rate. The cell boundaries, decorated with γ/γ′ eutectics, μ-phase precipitates and high density of dislocations, show enrichment of γ′ forming elements and low-angle misorientations. Dislocations trapped in the intra-cellular regions are characterized as statistically stored dislocations with no detectable contribution to lattice curvature, and are the results of the interaction between dislocations and γ′ precipitates.

Background: The optimal pulmonary revascularisation strategy in high-risk pulmonary embolism (PE) requiring implantation of extracorporeal membrane oxygenation (ECMO) remains controversial., Methods: We conducted a systematic review and meta-analysis of evidence comparing mechanical embolectomy and other strategies, including systemic thrombolysis, catheter-directed thrombolysis or ECMO as stand-alone therapy, with regard to mortality and bleeding outcomes., Results: We identified 835 studies, 17 of which were included, comprising 327 PE patients. Overall, 32.4% were treated with mechanical pulmonary reperfusion (of whom 85.9% had surgical embolectomy), while 67.6% received other strategies. The mortality rate was 22.6% in the mechanical reperfusion group and 42.8% in the "other strategies" group. The pooled odds ratio for mortality with mechanical reperfusion was 0.439 (95% CI 0.237-0.816) (p=0.009; I 2 =35.2%) versus other reperfusion strategies and 0.368 (95% CI 0.185-0.733) (p=0.004; I 2 =32.9%) for surgical embolectomy versus thrombolysis. The rate of bleeding in patients under ECMO was 22.2% in the mechanical reperfusion group and 19.1% in the "other strategies" group (OR 1.27, 95% CI 0.54-2.96; I 2 =7.7%). The meta-regression model did not identify any relationship between the covariates "more than one pulmonary reperfusion therapy", "ECMO implantation before pulmonary reperfusion therapy", "clinical presentation of PE" or "cancer-associated PE" and the associated outcomes., Conclusions: The results of the present meta-analysis and meta-regression suggest that mechanical reperfusion, notably by surgical embolectomy, may yield favourable results regardless of the timing of ECMO implantation in the reperfusion timeline, independent of thrombolysis administration or cardiac arrest presentation., Competing Interests: Conflict of interest: G. Piazza has received research grant support from Bristol Myers Squibb/Pfizer Alliance, Janssen, Boston Scientific Corporation, Amgen and Bayer, and consulting fees from Amgen, Agile, Pfizer, and the Prairie Education and Research Cooperative. No other author has any conflict of interest to declare., (Copyright ©The authors 2022. For reproduction rights and permissions contact permissions@ersnet.org.)

We report a novel plastic deformation mechanism of bulk metallic glass composites (BMGCs) containing metastable β-Ti dendrites. Plastic deformation of the BMGCs beyond the ultimate tensile strength is mediated by cooperative shear events, which comprise a shear band in the glassy matrix and a continuous ω-Ti band with a thickness of ∼10  nm in the β-Ti dendrite. The cooperative shear leads to serrated shear avalanches. The formation of narrow ω-Ti bands is caused by high local strain rates during the cooperative shear. The cooperative shear mechanism enriches the deformation mechanisms of BMGCs and also deepens the understanding of ω-Ti formation.

All metallic glasses (MGs), irrespective of their compositions, become brittle in the intermediate temperature range of 0.6-0.7 T g However, most materials are expected to carry higher strains during deformation with increasing temperature. This behavior of MGs is explained by describing the competition between shear banding and diffusive relaxation processes, and is reminiscent of the "intermediate temperature ductility minimum" observed in polycrystalline metals., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Extracorporeal Membrane Oxygenation (ECMO) has been suggested for cardiopulmonary support in patients with massive pulmonary embolism (PE) refractory to other treatment or as bridging to embolectomy. The survival benefit from ECMO in patients with massive PE remains unclear., Methods: Here, we describe 5 cases in which ECMO was used as cardiopulmonary support following massive near-fatal pulmonary embolism., Results: The overall mortality in patients with massive PE that received ECMO support was 40%. Death occurred secondary to ECMO-related complication in one case and due to inability to maintain adequate cerebral perfusion despite ECMO support in the second case., Conclusions: ECMO can be considered as a treatment modality for patients with massive PE., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Venoarterial extracorporeal membrane oxygenation (ECMO) provides systemic arterial support without directly unloading the left heart, which causes an elevated left ventricular (LV) pressure. The aim of the present study was to investigate the adjunctive application of the Impella device for LV unloading in patients during ECMO. Methods: This retrospective cohort study included patients who received Impella support in addition to venoarterial ECMO between April 2012 and December 2015. ECMO cannulation was performed peripherally or centrally, while the Impella device was surgically inserted into the femoral artery or the right axillary artery. Results: Among 62 patients, 10 (16.1%) received an Impella device during ECMO support. Following Impella support, right atrial pressure improved from a median of 18 (IQR, 14-24) mmHg to 13 (IQR, 10-15) mmHg and pulmonary wedge pressure improved from 30 (IQR, 26-35) mmHg to 16 (IQR, 12-19) mmHg in all the patients (p value < 0.001). Follow-up transthoracic echocardiograms (n = 6) showed a median decrease of 0.8 cm in LV end-diastolic volume (p value = 0.021). There were 5 (50%) in-hospital deaths due to sustained brain injury (n = 3) and refractory cardiogenic shock (n = 2). The remaining 5 patients were discharged and successfully bridged to more permanent LV assist device (n = 2) or heart transplantation (n = 3). Conclusion: The findings of the present study indicate that the application of the Impella device during ECMO support is effective in LV unloading and confers optimal hemodynamic support.

Background Patients undergoing transcatheter aortic valve replacement can experience severe perioperative complications leading to hemodynamic instability and death. Venoarterial extracorporeal membrane oxygenation can be used to provide cardiorespiratory support during this time. Methods From 2012 to 2015, of 247 patients who underwent transcatheter aortic valve replacement, 6 (2.42%) required extracorporeal membrane oxygenation support. Their mean age was 82 ± 7.4 years, mean Society of Thoracic Surgeons score was 9.4 ± 6.6, and mean aortic gradient was 28.3 ± 12 mm Hg. Rescue extracorporeal membrane oxygenation was required for hemodynamic instability due to ventricular fibrillation ( n = 1), respiratory failure ( n = 1), left ventricular wall rupture ( n = 2), and aortic annulus rupture ( n = 1). In one patient, prophylactic extracorporeal membrane oxygenation was required due to advanced heart failure. Additional procedures included valve-in-valve implantation ( n = 1), conversion to an open procedure ( n = 3), and intraaortic balloon pump insertion ( n = 1). Results The median hospital stay was 20 days. There were 2 hospital deaths in patients whose hospital course was complicated by left ventricular wall rupture or aortic annulus rupture with resulting tamponade. Among the 4 survivors, one required continuous ventilator support following discharge, and 3 experienced no major complications during the first month after discharge. Conclusions Extracorporeal membrane oxygenation can be considered a viable option for high-risk patients undergoing transcatheter aortic valve replacement and those who develop cardiac complications following this procedure and require cardiorespiratory support.

Objectives: To describe the first single center experience with a novel aspiration thrombectomy device., Background: The appearance of inferior vena cava or right-sided intracardiac thrombus may prompt consideration of percutaneous thrombectomy as a method to prevent new or worsening pulmonary embolism (PE). The AngioVac is a novel thrombectomy device composed of a cannula and extracorporeal circuit with filter for pump-assisted removal of intravascular debris which is coupled with a reinfusion catheter for return of blood to the patient. The device has been approved by the United States Food and Drug Administration since 2009. This report represents the first significant case series describing its use, feasibility and outcomes in evacuating large caval thrombi or intracardiac masses in PE., Methods: This is a retrospective analysis of patient and case characteristics and in-hospital clinical outcomes of AngioVac thrombectomy in 14 consecutive patients treated between April 2010 and July 2013 at our institution., Results: Fourteen consecutive patients (mean age 50, 64% female) underwent 15 AngioVac procedures over 40 months. Indications included intracardiac mass (73%), acute PE (33%), and caval thrombus (73%). Four patients (27%) were in shock at the start of the procedure. Peri-procedure mortality was 0% and in-hospital mortality was 13% at a mean follow-up of 23 days. There were no pulmonary hemorrhages, strokes or myocardial infarctions. Though 73% had a post procedural drop in hematocrit, only two bleeding events were related to access site and required a transfusion., Conclusions: AngioVac thrombectomy is feasible in critically ill patients with acute DVT or PE and large caval thrombi or intracardiac masses., (© 2015 Wiley Periodicals, Inc.)

The risk of rupture of a left ventricular (LV) pseudoaneurysm ranges from 30% to 45% in the first year. Open surgical repair carries high mortality related to anatomic complexity and patient comorbidities. Percutaneous closure may offer a viable alternative to surgical intervention in this cohort. Herein, we describe 3 unique cases of transcatheter LV pseudoaneurysm closure., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Incomplete double aortic arch is a rare anomaly resulting from atresia rather than complete involution in the distal left arch resulting in a non-patent fibrous cord between the left arch and descending thoracic aorta. This anatomic anomaly may cause symptomatic vascular rings, leading to stridor, wheezing, or dysphagia, requiring surgical transection of the fibrous cord. Herein, we describe an asymptomatic 59 year-old man presenting for contrast-enhanced CT angiography to assess cardiac anatomy prior to radiofrequency ablation, who was incidentally found to have an incomplete double aortic arch with hypoplasia of the left arch segment and an aortic diverticulum. Recognition of this abnormality by imaging is important to inform both corrective surgery in symptomatic patients, as well as assist in the planning of percutaneous coronary and vascular interventions., (Copyright © 2012 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Effective anticoagulation is mandatory for pregnant women with mechanical heart valves. Oral anticoagulants offer the best maternal protection against thrombosis, but their use might be associated with an appreciable risk of fetal malformations and pregnancy loss. By contrast, heparin derivatives are associated with a reduced risk of fetal damage, but an increased risk of valve thrombosis in the mother, even with appropriate dose adjustment and monitoring of therapeutic efficacy. Given the varying risks of available anticoagulation strategies, and the paucity of data to inform the optimal approach, no single accepted treatment option exists for pregnant women with mechanical prosthetic valves. Although low-molecular-weight heparin is considered more efficacious than unfractionated heparin, treatment failures, even at therapeutic levels of factor Xa inhibition, have been reported. The risk of warfarin-related embryopathy might be overstated, particularly at doses ≤ 5 mg daily. We advocate an individualized anticoagulation strategy that takes into account the patient's preferences, calls for the use of vitamin K antagonists throughout pregnancy (substituted with a heparin derivative only close to term) for those patients at the greatest risk of thromboembolism, and relies on close multidisciplinary collaboration between the cardiac and obstetric care teams.

A 69-year-old man underwent transradial catheterization (TRC) with successful percutaneous coronary intervention (PCI), but developed a radial artery perforation. Guiding catheter re-positioning and prolonged balloon inflation were unable to provide hemostasis. Successful reconstruction of the perforated vessel required the unconventional and novel use of a coronary polytetrafluoroethylene-covered stent graft.

The development of transcatheter valvular therapeutics has revolutionized interventional cardiology over the past decade. Nonetheless, despite these prominent advances in percutaneous valve technology, numerous obstacles regarding safety and efficacy must be overcome before the precise clinical role of these devices becomes clear. This article discusses the current status of transcatheter valve replacement and repair as it pertains to the aortic and mitral valve and deliberates on the bright future of a promising tool that will drastically affect clinical interventional practice., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Incidence of extracranial carotid aneurysm is rare and represents a challenge to treatment strategy. Two patients presented to us a couple of years apart with pulsatile neck swellings. We propose that the extracranial carotid artery pseudoaneurysm was as a result of direct extension from tuberculous lymphadenitis and discuss the management of these patients.

Tuberculous peritonitis and tuberculous endometritis are extremely rare entities in the Western world. In this article, we discuss a rare case of a 40-year-old Nigerian female presenting with abdominal pain, distension and secondary amenorrhea, and show that a high clinical suspicion combined with minimally invasive procedures can help physicians make the diagnosis, avoid extensive surgery, and rapidly initiate appropriate therapy.

Pericardial constriction secondary to metastatic adenocarcinoma is exceedingly rare. We present the first recorded case of pericardial constriction secondary to metastatic signet-ring mucinous adenocarcinoma diagnosed by echocardiography. The cornerstones of echocardiographic diagnosis of constriction are the following: interventricular septal bounce phasic with respiration, M-mode recordings of the inferior vena cava, and the characteristic Doppler velocity patterns recorded from the mitral valve, hepatic veins, and mitral annulus.