Improved optical quality of heteroepitaxially grown metal-organic framework thin films by modulating the crystal growth.

Fabricating high-quality thin films of metal-organic frameworks (MOFs) is important for integrating MOFs in various applications. Specifically, optical/electrical devices require MOF thin films that are crystallographically oriented, with closely packed crystals and smooth surfaces. Although the heteroepitaxial growth approach of MOFs on metal hydroxides has been demonstrated to control the orientation of the three crystallographic axes, the fabrication of MOF thin films with both three-dimensional crystallographic orientation and smooth surfaces remains a challenge. In this study, we report the fabrication of high-quality thin films of MOFs with closely packed MOF crystals, smooth surfaces, optical transparency, and crystal alignment by modulating the crystal growth of MOFs using the heteroepitaxial growth approach. High-quality thin films of Cu-paddlewheel-based pillar-layered MOFs are fabricated on oriented Cu(OH)2 thin films via epitaxial growth using acetate ions as modulators to control the crystal morphology. Increasing the modulator concentration results in a uniform crystal shape with a relatively long one-dimensional pore direction and uniform heterogeneous nucleation over the entire film. The MOF thin films fabricated using the modulator exhibit high optical transparency. High-quality MOF thin films with dense and flat surfaces will pave the way for integrating MOFs into sophisticated optical and electrical devices.

[The Long-term Results of Valve Sparing Aortic Root Replacement and Aortic Cusp Repair for Aortic Regurgitation].

We reported our long-term results of valve sparing aortic root replacement (VSRR) and aortic cusp repair for aortic regurgitation( AR) were satisfactory. Three hundred twenty-seven patients had VSRR, and 164 patients of them had aortic cusp repair for prolapse. At 10 years after the operation, the overall survival was 91.5%, the freedom from more than mild recurrent AR was 71.2%, and the freedom from aortic valve reoperation was 82.0%. As for the aortic cusp repair technique, there was no significant difference in the mid-term results of the recurrent AR and reoperation for the aortic valve between the central plication technique and the resuspension technique (two layers of continuous mattress sutures placed the entire length of the free margin of the aortic cusp). The resuspension technique might be useful for repairing the aortic cusp with prolapse. Furthermore, among the patients with acute aortic dissection, connective tissue disease, or aortitis, the long-term results of VSRR and aortic cusp repair were also satisfactory.

Intense impact of IL-1ß expressing inflammatory macrophages in acute aortic dissection.

There is no treatment for acute aortic dissection (AAD) targeting inflammatory cells. We aimed to identify the new therapeutic targets associated with inflammatory cells. We characterized the specific distribution of myeloid cells of both human type A AAD samples and a murine AAD model generated using angiotensin II (ANGII) and ß-aminopropionitrile (BAPN) by single-cell RNA sequencing (scRNA-seq). We also examined the effect of an anti-interleukin-1ß (IL-1ß) antibody in the murine AAD model. IL1B+ inflammatory macrophages and classical monocytes were increased in human AAD samples. Trajectory analysis demonstrated that IL1B+ inflammatory macrophages differentiated from S100A8/9/12+ classical monocytes uniquely observed in the aorta of AAD. We found increased infiltration of neutrophils and monocytes with the expression of inflammatory cytokines in the aorta and accumulation of inflammatory macrophages before the onset of macroscopic AAD in the murine AAD model. In blocking experiments using an anti-IL-1ß antibody, it improved survival of murine AAD model by preventing elastin degradation. We observed the accumulation of inflammatory macrophages expressing IL-1ß in both human AAD samples and in a murine AAD model. Anti-IL-1ß antibody could improve the mortality rate in mice, suggesting that it may be a treatment option for AAD.

Machine learning-assisted chemical design of highly efficient deicers.

The use of deicers in urban areas, on runways and aircrafts has raised concerns about their environmental impact. Understanding the ice-melting mechanism is crucial for developing environmentally friendly deicers, yet it remains challenging. This study employs machine learning to investigate the ice penetration capacity (IPC) of 21 salts and 16 organic solvents as deicers. Relationships between their IPC and various physical properties were analysed using extreme gradient boosting (XGBoost) and Shapley additive explanation (SHAP). Three key ice-melting mechanisms were identified: (1) freezing-point depression, (2) interactions between deicers and H2O molecules and (3) infiltration of ions into ice crystals. SHAP analysis revealed different ice-melting factors and mechanisms for salts and organic solvents, suggesting a potential advantage in combining the two. A mixture of propylene glycol (PG) and sodium formate demonstrated superior environmental impact and IPC. The PG and sodium formate mixture exhibited higher IPC when compared to six commercially available deicers, offering promise for sustainable deicing applications. This study provides valuable insights into the ice-melting process and proposes an effective, environmentally friendly deicer that combines the strengths of organic solvents and salts, paving the way for more sustainable practices in deicing.

Impact of maximum phonation time on postoperative dysphagia and prognosis after cardiac surgery.

Objective: The incidence of postoperative complications, including dysphagia, increases as the population undergoing cardiovascular surgery ages. This study aimed to explore the potential of maximum phonation time (MPT) as a simple tool for predicting postextubation dysphagia (PED) and major adverse cardiac and cerebrovascular events (MACCEs). Methods: This retrospective study included 442 patients who underwent elective cardiac surgery at a university hospital. MPT was measured before surgery, and patients were stratified into 2 groups based on normal and abnormal MPTs. Postoperative complications, including PED and MACCEs, were also investigated. Swallowing status was assessed using the Food Intake Level Scale. Results: MPT predicted PED with prevalence of 11.0% and 18.0% in the normal and abnormal MPT groups, respectively (P = .01). During the follow-up period, MACCEs developed in 17.0% of patients. Frailty, European System for Cardiac Operative Risk Evaluation II score, PED, and MPT were markedly associated with MACCEs (adjusted hazard ratios: 2.25, 1.08, 1.96, and 0.96, respectively). Mediation analysis revealed that MPT positively influenced PED and MACCEs, whereas PED positively influenced MACCEs. The trend in restricted cubic spline analysis indicated that the hazard ratio for MACCEs increased sharply when MPT was <10 seconds. Conclusions: These findings underscore the potential of MPT as a valuable tool in the preoperative assessment and management of patients undergoing cardiac surgery. By incorporating MPT into routine preoperative evaluations, clinicians can identify patients at a higher risk of PED and MACCEs, allowing for targeted interventions and closer postoperative monitoring. This may improve patient outcomes and reduce the health care costs associated with these complications.

Anterolateral thoracotomy with partial sternotomy: a feasible approach for treating the complex pathology of the aortic arch.

OBJECTIVES: Our goal was to review our surgical experiences in patients with complex pathologies of the aortic arch who have undergone anterolateral thoracotomy with a partial sternotomy (ALPS). METHODS: From October 2019 to November 2023, a total of 23 patients underwent one-stage repairs of complex pathologies of the aortic arch through the ALPS approach. The mean age was 61.9 ± 16.7 years old. The aortic pathologies were as follows: aorta-related infection in 11 (aorto-oesophageal fistula: 4, graft infection: 6, native aortic infection: 1); aortic dissection in 9 including shaggy aorta in 2, non-dissecting aneurysm in 1, and coarctation of the aorta (CoA) in 2. RESULTS: Eighteen patients underwent aortic replacement from either the sinotubular junction or the ascending aorta to the descending aorta; 1 patient underwent it from the aortic root to the descending aorta (redo Bentall procedure and extensive aortic arch replacement); 3 patients underwent it from the aortic arch between the left carotid artery and left subclavian artery to the descending aorta; and 1 patient underwent a descending aortic replacement. Ten patients underwent omentopexy, latissimus dorsi muscle flap installation or both procedures. The hospital mortality rate was 13.0% (3/23). The overall survival and freedom from aortic events were 73.3%±10.2% and 74.1%±10.2%, respectively, at the 3-year follow-up. There was an absence of aorta-related deaths, and no recurrent infections were identified. CONCLUSIONS: The short-term outcomes using the ALPS approach for the treatment of complex pathologies of the aortic arch were acceptable. Further studies will be required to determine the long-term results.

Pre-emptive Aortic Side Branch Embolization during Endovascular Aneurysm Repair Using the Excluder Stent-Graft System: A Prospective Multicenter study.

PURPOSE: To evaluate the effectiveness and safety of pre-emptive transcatheter arterial embolization (P-TAE) for aortic side branches (ASBs) to prevent Type 2 endoleaks (EL2) before endovascular aneurysm repair (EVAR) using the Excluder stent-graft system (Excluder). MATERIALS AND METHODS: In this prospective, multicenter study, 80 patients (mean age, 79.1 years [SD ± 6.7]; 85.0% were men; mean aneurysmal sac diameter, 48.4 mm [SD ± 7.4]) meeting the eligibility criteria were prospectively enrolled from 9 hospitals. Before EVAR, P-TAE was performed to embolize the patent ASBs originating from the abdominal aortic aneurysm. Contrast-enhanced computed tomography (CT) was performed at 1 month and 6 months after EVAR. The primary endpoint was EL2 incidence at 6 months, and the secondary endpoints were aneurysmal sac diameter changes at 6 and 12 months, P-TAE outcomes, adverse events related to P-TAE, reintervention, and aneurysm-related mortality. RESULTS: All patients successfully underwent P-TAE without serious. Coil embolization was successful in 81.6% of ASBs. EL2 incidence at 6 months was identified in 18 of 70 (25.7%) patients. Aneurysmal sac diameter shrinkage (≥5 mm) was observed in 30.0% of patients at 6 months and in 40.9% at 12 months. Only 1 patient required reintervention for EL2 within 1 year of EVAR; aneurysm-related deaths were not observed. CONCLUSIONS: P-TAE for ASBs before EVAR using Excluder is a safe and effective strategy. It aids in achieving early aneurysmal sac shrinkage and reduces EL2 reintervention at 1 year after EVAR.

Side branch embolization before endovascular abdominal aortic aneurysm repair to prevent type II endoleak: A prospective multicenter study.

PURPOSE: The purpose of the study was to evaluate the efficacy and safety of pre-emptive transcatheter arterial embolization (P-TAE) of aortic side branches to prevent type II endoleak in patients with abdominal aortic aneurysm after endovascular abdominal aneurysm repair (EVAR). MATERIALS AND METHODS: This multicenter, prospective, single-arm trial enrolled 100 patients with abdominal aortic aneurysm from nine hospitals between 2018 and 2021. There were 85 men and 15 women, with a mean age of 79.6 ± 6.0 (standard deviation) years (range: 65-97 years). P-TAE was attempted for patent aortic side branches, including the inferior mesenteric artery, lumbar arteries, and other branches. The primary endpoint was late type II endoleak incidence at 6 months post-repair. Secondary endpoints included changes in aneurysmal sac diameter at 6- and 12 months, complications, re-intervention, and aneurysm-related mortality. Aneurysm sac changes at 6- and 12 months was compared between the late and no-late type II endoleak groups. RESULTS: Coil embolization was successful in 80.9% (321/397) of patent aortic side branches, including 86.3% of the inferior mesenteric arteries, 80.3% of lumbar arteries, and 55.6% of other branches without severe adverse events. Late type II endoleak incidence at 6 months was 8.9% (8/90; 95% confidence interval: 3.9-16.8%). Aneurysm sac shrinkage > 5 mm was observed in 41.1% (37/90) and 55.3% (47/85) of the patients at 6- and 12-months post-EVAR, respectively. Patients with late type II endoleak had less aneurysm sac shrinkage than those without type II endoleak at 12 months (-0.2 mm vs. -6.0 mm; P = 0.040). No patients required re-intervention for type II endoleak, and no aneurysm-related mortalities occurred. CONCLUSION: P-TAE is safe and effective in preventing type II endoleak, leading to early sac shrinkage at 12 months following EVAR.

Suppressed pediatric asthma hospitalizations during the COVID-19 pandemic in Japan, from a national survey.

BACKGROUND: Acute asthma exacerbation in children is often caused by respiratory infections. In this study, a coordinated national surveillance system for acute asthma hospitalizations and causative respiratory infections was established. We herein report recent trends in pediatric acute asthma hospitalizations since the COVID-19 pandemic in Japan. METHODS: Thirty-three sentinel hospitals in Japan registered all of their hospitalized pediatric asthma patients and their causal pathogens. The changes in acute asthma hospitalization in children before and after the onset of the COVID-19 pandemic and whether or not COVID-19 caused acute asthma exacerbation were investigated. RESULTS: From fiscal years 2010-2019, the median number of acute asthma hospitalizations per year was 3524 (2462-4570), but in fiscal years 2020, 2021, and 2022, the numbers were 820, 1,001, and 1,026, respectively (the fiscal year in Japan is April to March). This decrease was observed in all age groups with the exception of the 3- to 6-year group. SARS-CoV-2 was evaluated in 2094 patients from fiscal years 2020-2022, but the first positive case was not detected until February 2022. Since then, only 36 of them have been identified with SARS-CoV-2, none of which required mechanical ventilation. Influenza, RS virus, and human metapneumovirus infections also decreased in FY 2020. In contrast, 24% of patients had not been receiving long-term control medications before admission despite the severity of bronchial asthma. CONCLUSION: SARS-CoV-2 was hardly detected in children with acute asthma hospitalization during the COVID-19 pandemic. This result indicated that SARS-CoV-2 did not induce acute asthma exacerbation in children. Rather, infection control measures implemented against the pandemic may have consequently reduced other respiratory virus infections and thus acute asthma hospitalizations during this period. However, the fact that many hospitalized patients have not been receiving appropriate long-term control medications is a major problem that should be addressed.

Accelerated Water Desorption of Oligomeric Poly(ethylene glycol) by Addition of Poly(propylene glycol) for Energy-Efficient Water Recovery Systems.

Adsorbents are used to recover water vapor from the atmosphere in desiccant air conditioning (DAC) and atmospheric water harvesting (AWH) systems. Solid adsorbents have been conventionally used in these systems, though liquid adsorbents are considered to be more effective for energy-efficient fluidic thermosystems because of their low regeneration temperatures (45-70 °C). While most previous studies have focused on improving the adsorption performance, the desorption performance of adsorbents can also be a critical factor in improving the energy efficiency of these systems. Thus, this study aimed to improve the water desorption efficiency, focusing on the liquid adsorbents. We found that mixing hydrophobic molecules into a liquid adsorbent decreases the desorption temperature and increases the water-desorption efficiency. Oligomeric poly(ethylene glycol) (PEG), a common moisture-adsorbing liquid oligomer used in detergents and cosmetics, was selected as the liquid adsorbent. Oligomeric poly(propylene glycol) (PPG), which has a structure analogous to PEG and lower hygroscopicity, was selected as the hydrophobic molecule. Water adsorption and desorption experiments showed that the mixture of PPG with PEG promoted the desorption of water molecules beyond that of PEG, while thermogravimetric differential thermal analysis revealed a decrease in the water desorption temperature with increasing PPG content. The improved desorption efficiency was ascribed to the likely water adsorption equilibrium between PEG and PPG in the blend; water molecules are preferentially desorbed from PPG, which has weaker water-adsorbate interactions. The proposed concept is expected to be incorporated into various hygroscopic liquids to develop energy-efficient liquid adsorbents for DAC and AWH.

Long-term Results of Valve-Sparing Aortic Root Replacement and Aortic Cusp Repair.

BACKGROUND: Long-term results of valve-sparing aortic root replacement (VSRR) and aortic cusp repair for aortic regurgitation are unclear. METHODS: VSRR by reimplantation was performed in 363 patients. Tricuspid aortic valve (TAV) and bicuspid aortic valve were found in 285 and 71 patients, respectively. RESULTS: Aortic cusp repair was performed in 268 patients. Of patients with TAV 129 had central plication of the Arantius node, 36 had free margin resuspension, and 71 had reinforcement. Mean follow-up was 71.4 months. Among TAV patients freedom from aortic valve reoperation at 10 and 15 years was 85.1% and 78.3%, respectively. Freedom from aortic valve reoperation at 10 years was lower in patients with cusp prolapse than without (77.4% vs 93.2%, P = .007). The overall freedom from more than mild aortic regurgitation at 10 and 15 years was 72.4% and 64.0%, respectively. It was also significantly greater in patients without cusp prolapse (78.4% vs 67.7%, P = .02). As for the cusp repair technique the freedom from aortic valve reoperation at 10 years was significantly better in patients who underwent only resuspension or reinforcement techniques compared with patients who underwent only central plication technique (100% vs 72.8%, P = .008). CONCLUSIONS: Long-term results of VSRR with aortic cusp repair were satisfactory. The resuspension technique appears to be useful for repairing aortic cusp prolapse in patients with TAV.

Expanded polytetrafluoroethylene conduits with curved and handsewn bileaflet designs for right ventricular outflow tract reconstruction.

OBJECTIVE: This study reviewed the application of curved and bileaflet designs to pulmonary expanded polytetrafluoroethylene conduits with diameters of 10 to 16 mm and characterized this conduit on in vitro experiment, including particle image velocimetry. METHODS: All patients who received this conduit between 2010 and 2022 were evaluated. Three 16-mm conduits were tested in a circulatory simulator at different cardiac outputs (1.5-3.6 L/minute) and bending angles (130°-150°). RESULTS: Fifty consecutive patients were included. The median operative body weight was 8.4 kg (range, 2.6-12 kg); 10-, 12-, 14-, and 16-mm conduits were used in 1, 4, 6, and 39 patients, respectively. In 34 patients, the conduit was implanted in a heterotopic position. The overall survival rate was 89% at 8 years with 3 nonvalve-related deaths. There were 10 conduit replacements; 5 16-mm conduits (after 8 years) and 1 12-mm conduit (after 6 years) due to conduit stenosis, and the remaining 4 for reasons other than conduit failure. Freedom from conduit replacement was 89% and 82% at 5 and 8 years, respectively. Linear mixed-effects models with echocardiographic data implied that 16-mm conduits were durable with a peak velocity <3.5 m/second and without moderate/severe regurgitation until the patient's weight reached 25 kg. In experiments, peak transvalvular pressure gradients were 11.5 to 25.5 mm Hg, regurgitant fractions were 8.0% to 14.4%, and peak Reynolds shear stress in midsystolic phase was 29 to 318 Pa. CONCLUSIONS: Our conduits with curved and bileaflet designs have acceptable clinical durability and proven hydrodynamic profiles, which eliminate valve regurgitation and serve as a reliable bridge to subsequent conduit replacement.

Palivizumab prophylaxis in preterm infants and subsequent wheezing/asthma: 10-year follow-up study.

BACKGROUND: Respiratory syncytial virus (RSV) causes not only infantile recurrent wheezing but also the development of asthma. To investigate whether palivizumab, an anti-RSV monoclonal antibody, prophylaxis given to preterm infants during the first RSV season reduces the incidence of subsequent recurrent wheezing and/or development of asthma, at 10 years of age. METHODS: We conducted an observational prospective multicenter (52 registered hospitals in Japan) case-control study in preterm infants with a gestational age between 33 and 35 weeks followed for 6 years. During the 2007-2008 RSV season, the decision to administer palivizumab was made based on standard medical practice (SCELIA study). Here, we followed these subjects until 10 years of age. Parents of study subjects reported the patients' physician's assessment of recurrent wheezing/asthma, using a report card and a novel mobile phone-based reporting system using the internet. The relationship between RSV infection and asthma development, as well as the relationship between other factors and asthma development, were investigated. RESULTS: Of 154 preterm infants enrolled, 113 received palivizumab during the first year of life. At 10 years, although both recurrent wheezing and development of asthma were not significantly different between the treated and untreated groups, maternal smoking with aeroallergen sensitization of the patients was significantly correlated with physician-diagnosed asthma. CONCLUSIONS: In contrast to the prior study results at 6 years, by 10 years palivizumab prophylaxis had no impact on recurrent wheezing or asthma, but there was a significant correlation between maternal passive smoking with aeroallergen sensitization and development of asthma by 10 years of age.

[Acute Aortic Dissection with Visceral Malperfusion Syndrome].

Malperfusion syndrome of the visceral branches associated with acute aortic dissection brings an extremely poor outcomes leading to perioperative and long-term mortality in both Stanford type A and type B acute aortic dissection. The conventional surgical strategy for these cases has been to prioritize aortic repair and to improve blood flow of true lumen in aorta and visceral branches. Today, various techniques for early reperfusion have been reported. For bowel ischemia, it is necessary to evaluate substantial ischemia of the intestinal tract and hypoperfusion of the superior mesenteric artery( SMA) using contrast-enhanced computed tomography( CT) and intraoperative transesophageal echocardiography in addition to clinical presentation. The most important factor of the surgical intervention is the improvement of true luminal blood flow by reconstruction of the central aorta. However, an intervention to SMA prior to central aortic repair might be an important process for patients with Stanford type A acute aortic dissection to avoid irreversible bowel necrosis. In type B aortic dissection, thoracic endovascular aortic repair (TEVAR) with or without provisional extension to induce complete attachment (PETTICOAT) technique and additional SMA intervention based on intraoperative contrast findings are necessary. Renal malperfusion is also a risk factor of postoperative accute kidney injury( AKI) and perioperative mortality. The revascularizations of renal arteries might improve outcomes when renal blood flow was not recovered with central aortic repair.

Mechanism of sac expansion without evident endoleak analyzed with X ray phase-contrast tomography.

Objective: Synchrotron radiation-based X ray phase-contrast tomography (XPCT) was used in this study to evaluate abdominal aorta specimens from patients with sac expansion without evidence of an endoleak (endotension) following endovascular aortic repair (EVAR) for an abdominal aortic aneurysm (AAA). The aim of this study was to analyze the morphologic structure of the aortic wall in patients with this condition and to establish the cause of the endotension. Methods: Human aortic specimens of the abdominal aorta were obtained during open repair, fixed with formalin, and analyzed among three groups. Group A was specimens from open abdominal aortic aneurysm repairs (n = 7). Group E was specimens from sac expansion without an evident endoleak after EVAR (n = 7). Group N was specimens from non-aneurysmal "normal" cadaveric abdominal aortas (n = 5). Using XPCT (effective voxel size, 12.5 µm; density resolution, 1 mg/cm3), we measured the density of the tunica media (TM) in six regions of each sample. Then, any changes to the elastic lamina and the vasa vasorum were analyzed pathologically. The specimens were immunohistochemically examined with anti-CD31 and vascular endothelial growth factor antibodies. Results: The time from EVAR to open aortic repair was 64.2 ± 7.2 months. There were significant differences in the thickness of the TM among three groups: 0.98 ± 0.03 mm in Group N; 0.31 ± 0.01 mm in Group A; and 0.15 ± 0.03 mm in Group E (P < .005). There were significant differences in the TM density among the groups: 1.087 ± 0.004 g/cm3 in Group N; 1.070 ± 0.001 g/cm3 in Group A; and 1.062 ± 0.007 g/cm3 in Group E (P < .005). Differences in the thickness and density of the TM correlated with the thickness of the elastic lamina; in Group N, uniform high-density elastic fibers were observed in the TM. By contrast, a thinning of the elastic lamina in the TM was observed in Group A. A marked thinness and loss of elastic fibers was observed in Group E. CD31 immunostaining revealed that the vasa vasorum was localized in the adventitia and inside the outer third of the TM in Group N, and in the middle of the TM in Group A. In Group E, the vasa vasorum advanced up to the intima with vascular endothelial growth factor-positive cells in the intimal section. Conclusions: XPCT could be used to demonstrate the densitometric property of the aortic aneurysmal wall after EVAR. We confirmed that the deformation process that occurs in the sac expansion after EVAR without evidence of an endoleak could be explained by hypoxia in the aortic wall.

Guidelines for the Management of Respiratory Infectious Diseases in Children in Japan 2022.

The members of the Japanese Society for Pediatric Infectious Diseases and the Japanese Society of Pediatric Pulmonology have developed Guidelines for the Management of Respiratory Infectious Diseases in Children with the objective of facilitating appropriate diagnosis, treatment and prevention of respiratory infections in children. The first edition was published in 2004 and the fifth edition was published in 2022. The Guideline 2022 consists of 2 parts, clinical questions and commentary, and includes general respiratory infections and specific infections in children with underlying diseases and severe infections. This executive summary outlines the clinical questions in the Guidelines 2022, with reference to the Japanese Medical Information Distribution Service Manual. All recommendations are supported by a systematic search for relevant evidence and are followed by the strength of the recommendation and the quality of the evidence statements.

Structural properties in ruptured mitral chordae tendineae measured by synchrotron-based X-ray phase computed tomography.

The link between the structural properties and the rupturing of chordae tendineae in the mitral valve complex is still unclear. Synchrotron-radiation-based X-ray phase computed tomography (SR-XPCT) imaging is an innovative way to quantitatively analyze three-dimensional morphology. XPCT has been employed in this study to evaluate the chordae tendineae from patients with mitral regurgitation and to analyze structural changes in the ruptured chordae tendineae in patients with this condition. Six ruptured mitral chordae tendineae were obtained during surgical repairs for mitral regurgitation and were fixed with formalin. In addition, 12 healthy chordae tendineae were obtained from autopsies. Employing XPCT (effective pixel size, 3.5 µm; density resolution, 1 mg cm-3), the density of the chordae tendineae in each sample was measured. The specimens were subsequently analyzed pathologically. The mean age was 70.2 ± 3.0 in the rupture group and 67.2 ± 14.1 years old in the control group (p = 0.4927). All scans of chorda tendineae with SR-XPCT were performed successfully. The mean densities were 1.029 ± 0.004 in the rupture group and 1.085 ± 0.015 g cm-3 in the control group (p < 0.0001). Density based on SR-XPCT in the ruptured mitral chordae tendineae was significantly lower compared with the healthy chorda tendinea. Histological examination revealed a change in the components of the connective tissues in ruptured chorda tendinea, in accordance with the low density measured by SR-XPCT. SR-XPCT made it possible to measure tissue density in mitral chordae tendineae. Low density in mitral chordae tendineae is associated with a greater fragility in ruptured mitral chordae tendineae.

Open Conversion with Explantation of Stent Grafts After Endovascular Aneurysm Repair for Abdominal Aortic Aneurysm.

BACKGROUND: Although endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) is widely used worldwide, the fact that it is associated with increased rates of reintervention has been considered a problem. This study aimed to analyze the outcomes of primary open AAA repair and open conversion with explantation of stent grafts after EVAR. METHODS: In this retrospective study, we enrolled 1,120 patients (open repair, n = 664; EVAR, n = 456) who underwent AAA repair at Kobe University from 1999 to 2019. Of the 664 patients who underwent open repair, 121 (patients who underwent primary open repair (POR) as a concomitant procedure and patients with ruptured AAA) were excluded from the study. The outcomes of POR were compared with those of open conversion with explantation of stent grafts. RESULTS: Of the 543 patients who underwent open repair, 513 underwent POR and 30 underwent open conversion with explantation of stent grafts. The operation time for POR was significantly less than that for open conversion with explantation. During surgery, patients who underwent open conversion with explantation required significantly more transfusions of red cell concentrate, fresh frozen plasma, and platelet concentrate than those who underwent POR. Overall, 30 patients who underwent open conversion with explantation required a total of 48 reinterventions before surgery. Hospital mortality rates were 0.7% and 0% in the POR and open conversion with explantation groups, respectively (P = 0.62). Although overall survival at 5 years in the POR group was significantly better than that in the open conversion with explantation group (89.3 ± 1.7% vs. 79.5 ± 9.6%; P = 0.01), there were no significant differences between the 2 groups regarding the freedom from aortic event (hospital death, reintervention, and aortic death). According to the multivariate analysis, open conversion with explantation was not an independent risk factor for late death. There were 20 patients who were hesitant to undergo OCE, although we recommended OCE. In a subgroup analysis, the overall mean cost borne by patients who underwent EVAR was approximately 2.3 times higher compared with that borne by patients who underwent POR. CONCLUSIONS: Although demanding, both early and long-term outcomes of OCE have been favorable in our present study. OCE is highly recommended in patients with persistent sac enlargement after EVAR.

Open-chest epicardial ablation of ventricular tachycardia during a left ventricular assist device implantation: a case report.

Background: Ventricular arrhythmias (VAs) are common after a left ventricular assist device (LVAD) implantation. Further, the majority of post-LVAD ventricular tachycardias (VTs) are secondary to a preexisting cardiomyopathy substrate. Intraoperative ablation of patients with recurrent preoperative VTs may reduce post-LVAD VTs. Case summary: A 59-year-old female with advanced heart failure due to non-ischaemic cardiomyopathy (LV ejection fraction = 24%) and recurrent VTs was referred for an LVAD implantation as a bridge to a heart transplant (INTERMACS Profile-5A). The previous endocardial ablation failed due to an epicardial arrhythmogenic substrate. Therefore, open-chest epicardial mapping during the LVAD implantation was indicated and three target areas of the arrhythmogenic substrate were found, which were ablated by radiofrequency applications. To minimize the cardiopulmonary bypass time, cardiopulmonary bypass was initiated after ablation, and then, an LVAD was implanted. An additional 68 min was required for mapping and ablation. All procedures were performed without any complications, and the post-operative course was uneventful. Thereafter, no VT episodes were observed without any anti-arrhythmic drugs during a 15-month follow-up with LVAD support. Discussion: Intraoperative epicardial mapping and ablation during an LVAD implantation can play an important role in the management of LVAD recipients with recurrent VAs.