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Pulmonary thromboendarterectomy (PTE) remains the treatment of choice for patients with operable chronic thromboembolic pulmonary hypertension (CTEPH). It is a technically demanding operation that offers patients with CTEPH improvements in survival and quality of life. In this article, we describe the operative technique of PTE in detail.

© 2020 Elsevier B.V. lithium-sulfur (Li-S) batteries have been regarded as one of the most promising systems for next-generation rechargeable batteries owing to their high energy density and low cost. However, the “Shuttle effect” of polysulfides and low sulfur utilization upon cycling are still hindering their practical applications. Herein, we report a series of marine organism-like hollow nanoarchitecture consisting of nitrogen (N) doped 1D carbon nanotubes (CNTs), which were derived from binary Fe/Ce Prussian blue analogs (PBAs) and melamine. This nitrogen-doped 3D hollow scaffold offers large inner space (ф ≈ 200 nm) and sufficient electric conducting for insulating sulfur and provides adsorption sites for immobilizing polysulphides. The introduced double metal species enable strong chemical adsorption toward polysulfides and could facilitate the redox reaction between sulfur and polysulphides. When applied in Li-S batteries, the as-prepared materials showed a high capacity of 1241 mAh g−1 and a stable cycling performance (1003 mAh g−1 after 100 cycles) at a current density of 0.2 C. The enhancement of electrochemical activity could be attributed to the 3D hollow architecture of the hybrid, in which the nitrogen-doping generates defects and active sites for improved interfacial adsorption. This work could inspire developing biomimetic architectures for high-performance Li-S batteries.

CdS/ZnSe multi quantum well (MQW) heterostructures with type II band offsets for blue-green semiconductor disk lasers were grown by metalorganic vapor-phase epitaxy (MOVPE) at T = 440 °C. The blurring of heterostructure interfaces during growth is investigated. There has been observed a blueshift of the emission line of heterostructures pumped from the side released from the GaAs substrate, in comparison with the emission line under pumping from the growth surface that indicates the change in the design of QWs during growth. Simulations of experimental X-ray diffraction curves also showed that the average composition of QW changes on CdZnS/ZnCdSe. It is shown that due to the strong mutual diffusion of Cd and Zn through the interfaces, it is possible to form the two ZnSSe/ZnCdSe/ZnCdS QWs with the I-type band offsets. Nevertheless, using light-assisted spreading resistance microscopy measurements on the cleaved cross-sections of the structures, carrier separation in QWs is observed, indicating the formation of a type II band offsets in the most of our heterostructures. The grown structures show intense luminescence, the radiation spectrum of which shifts to the short-wave side with the increase of the pump level.

Purpose Optimal intraoperative anticoagulation strategy for patients with heparin-induced thrombocytopenia (HIT) undergoing pulmonary thromboendarterectomy (PTE) that necessitates deep hypothermic circulatory arrest (DHCA) remains controversial. Cangrelor is an intravenous direct-acting P2Y12 platelet receptor antagonist that achieves therapeutic effect and eliminates rapidly. Its antiplatelet activity is unaffected by stagnation of blood, nor is it influenced by patient's age, renal status or hepatic function. We report our novel strategy and experience in utilizing cangrelor in combination with heparin for anticoagulation during cardiopulmonary bypass (CPB) and DHCA in HIT patients undergoing PTE. Methods Retrospective chart review of 297 patients who underwent PTE from January 2018 through June 2019 was performed. Patients with suspected, acute, subacute A/B, and remote HIT at the time of procedure were identified (n=7). All 7 patients received cangrelor with heparin intraoperatively for anticoagulation during CPB and DHCA. Our institutional intraoperative anticoagulation strategy for HIT patients is to administer a loading dose of cangrelor (30 μg/kg) prior to giving full-dose heparin for CPB. Cangrelor infusion is initiated at 4 μg/kg/min and is adjusted throughout CPB depending on the intraoperative VerifyNow P2Y12 reaction unit values. Cangrelor infusion is stopped 10 minutes before heparin reversal with protamine. Postoperatively, bivalirudin and warfarin were used for anticoagulation. Results Of these 7 patients, HIT was suspected in 3 patients (43%) at the time of procedure, whilst 1 patient had subacute B HIT and 1 patient had remote HIT. Acute HIT was confirmed by serotonin release assay in 2 patients (29%) who underwent emergent PTE. All patients survived the procedure. Intraoperative platelet transfusion was required by 4 patients (57%). There were no serious postoperative thrombotic events nor major bleeding complications that required re-operation. One in-hospital death was associated with advanced intracardiac malignancy. The mean postoperative hospital stay was 10.6±5.5 days. Conclusion In patients with various phases of HIT who require PTE, the use of cangrelor in combination with heparin may be a promising alternative intraoperative anticoagulation strategy providing acceptable outcomes.

Purpose Pulmonary artery sarcoma (PAS) is an exceedingly rare disease with historically poor survival. PAS is often mistaken for chronic thromboembolic pulmonary hypertension (CTEPH) owing to similarities in clinical presentation. Controversy exists regarding need to definitively differentiate PAS from CTEPH prior to surgical therapy. Furthermore lung resection would seem inferior palliation to tumor endarterectomy in a predominantly bilateral disease dominated by hemodynamic compromise. Methods Retrospective review of all patients who underwent pulmonary endarterectomy (PEA) and tumor resection surgery at a single institution between March 1992 and February 2019, identified 55 patients diagnosed with PAS. Results In this series of 55 patients (23 male, 32 female, age 23-82 years), median time from symptom onset to diagnosis was 8 months (IQR 5-12 months). Many patients were severely limited on initial assessment (median WHO Functional Class III). Forty-six patients (83.6%) had suspected PAS diagnosis prior to surgery. Preoperative testing identified bilateral disease (37/50 V/Q scans, 39/46 CTA) and PA mass (35/55) in majority of cases. Fifty patients (90.9%) had pathologically-confirmed bilateral pulmonary involvement, while 20 also had valvular or intracardiac tumor extension resected at time of surgery. A majority of sarcomas (87%) were classified as undifferentiated or intimal subtype and 64% were high-grade. PEA resulted in significant improvement in hemodynamics [mPAP decreased by 6 mmHg (p Conclusion PAS is a rare disease with poor prognosis. Tumor endarterectomy may alleviate symptoms and increase life-expectancy. Knowledge that PAS is a predominantly bilateral disease (90.9% in our series), suggests lung resection would rarely if ever be curative, whereas PEA can be diagnostic and effective treatment of hemodynamic compromise. Furthermore, earlier surgical treatment may enable earlier referral and tolerability of adjuvant chemoradiation or immunotherapy resulting in improved survival.

Introduction The prevalence of heart failure (HF) in men and women is similar. However, guideline directed medical and advanced heart therapies, including left ventricular assist devices (LVAD) and heart transplant (Htx) are underused in women. Hypothesis Sex-related differences are observed in advanced heart failure and may affect outcomes after LVAD and Htx. Methods TransAtlantic Registry on VAD and Transplant (TRAVIATA) is a retrospective, multinational (Italy, Sweden, Croatia, Netherlands, Belgium, USA) registry that includes patients with LVAD (HeartWare, Heartmate II) with bridge to transplant (BTT) strategy. Patients with HeartMate 3, BIVAD or total artificial heart devices were excluded. Primary outcomes include frequency of Htx, waitlist time and survival. Results A total of 524 patients (15.6% women) received LVAD with BTT treatment strategy from 2008 to 2017. Baseline characteristics between men and women were matched, including HVAD use (38.7% vs 47.6%, p = 0.142) with notable differences in LVEDD (7.0 (1.5) vs 6.3 (1.5) cm (IQR), p = 0.001), TAPSE (1.5 (0.5) vs 1.7 (0.5) cm (IQR), p = 0.02) and INTERMACS class 1-2 (43.3% vs 59.8%, p = 0.008). Frequency of Htx (57.9% vs 58.3%, p = 0.087) with a median waitlist time (369 (568) vs 311 (367) days (IQR), p = 0.07) was similar between men and women. Survival differences by Kaplan Meir analysis at 5 years (p = 0.925) were not observed. Post-LVAD complications were significant for increased stroke in women compared to men (24.4% vs 13.4%, p = 0.018). Conclusion In this multinational registry, there were no observed sex differences in frequency of Htx, waitlist time or survival. However, greater severity of disease at time of therapy in women may suggest delays in diagnosis or decision to enlist these patients for therapy, highlighting a potential discordance in use of advanced HF therapies by sex.

Purpose Highly effective direct-acting antiviral therapy for hepatitis C virus (HCV) allows the use of organs from viremic, nucleic acid test-positive (NAT+) donors in non-HCV-infected recipients. This opportunity potentially expands donor pool and decreases waitlist time. This study aims to examine the impact of utilizing HCV NAT+ donor heart on heart transplant (HTx) waitlist time. Methods We retrospectively analyzed 126 patients who were listed for HTx from April 2016 through April 2018 at our center. These patients were separated into 2 periods centered on April 27, 2017 when transplantation of HCV NAT+ donor hearts into non-HCV-infected recipients began. Results Baseline patient characteristics were similar between both periods. In Period 1, 74 patients were on HTx waitlist with 52 of them ultimately transplanted, whereas in Period 2, 52 patients were listed and 36 of them transplanted. Fifteen patients were transplanted with HCV NAT+ donor hearts since April 27, 2017. Transplant rate increased from 0.83 person-year in Period 1 to 2.31 person-year in Period 2 (p Conclusion Our single-center analysis demonstrates that utilization of HCV NAT+ donor heart has resulted in an increase in transplant rate and a reduction in HTx waitlist time. Further extended follow-up is needed to determine long-term safety and efficacy of this strategy.