Prediction of difficulty in cryoballoon ablation with a 3D deep learning model using polygonal mesh representation

Background

Cryoballoon ablation (CBA) is a useful treatment for pulmonary vein isolation (PVI). Some cases, however, are difficult to treat and may require multiple freezing procedures and/or touch-up ablation. Although several predictors of CBA difficulty have been reported, no report has been able to assess the spatial location and morphology of the left atrium (LA) and pulmonary veins (PVs). A polygonal mesh is a collection of vertices, edges, and faces that defines the shape of a polyhedral object, and is able to represent a spatial location with a small amount of information. We hypothesized that a deep learning model that learns mesh representation datasets could more accurately detect the CBA difficulty and that we could establish a novel evaluation method in CBA.

Purpose

The aim of this study was to create a model to predict CBA difficulty with a 3D deep learning model using polygonal mesh representation.

Methods and results

All the 140 patients who underwent CBA for drug-resistant atrial fibrillation between January 2015 and January 2022 were included. A 28-mm cryoballoon (Arctic Front Advance, Medtronic) was used in all cases. We defined CBA difficulty as requiring a touch-up ablation procedure to create complete PVI. We converted the volume data in DICOM format of the computed tomography images of PVs and LA to obj file format (shown in Figure 1), which supports the definition of the geometry for object surfaces using polygonal meshes. Next, we developed a deep learning model that could learn polygonal meshes and classify whether the CBA required touch-up ablation or not. Only a training dataset is used to train the deep learning model, and finally, a test dataset is used to evaluate the model metrics. The accuracy, area under the ROC curve, recall, precision, and f1-score of the deep learning model using the test dataset was 86.5%, 87.7%, 66.7%, 75.0%, 70.6%, respectively.

Conclusions

We developed a 3D deep learning model that can detect a difficulty in CBA using polygonal mesh representation. By predicting difficult cases in advance, we will be able to develop strategies to increase the success rate.

Funding Acknowledgement

Type of funding sources: None.

POS0197 SARS-CoV-2 INFECTION CAUSED THROMBOSIS IN THE LUPUS MODEL WITH ANTIPHOSPHOLIPID ANTIBODY, WHEREAS COVID-19 ASSOCIATED THROMBOSIS WAS IRRELEVANT IN PATIENTS WITH POSITIVE ANTIPHOSPHOLIPID ANTIBODY

Background

Thrombosis is a unique complication in coronavirus disease 2019 (COVID-19). We have reported that elevated ferritin and D-dimer on admission were the risk factors of thromboses by analyzing the patients sequentially admitted to our hospital due to COVID-19 (1). However, we have not analyzed thrombotic complications in the view of the antiphospholipid antibodies (aPLs), which are frequently detected in the COVID-19 patients.

Objectives

To elucidate the thrombogenic effects of aPLs in COVID-19, we analyzed the development of thrombosis in three lupus models after SARS-CoV-2 infection. Additionally, we evaluated the association of thrombotic events and the serum profile of aPLs in Japanese patients with COVID-19.

Methods

Three animal models of lupus (MRL-lpr/lpr, NZBxNZW F1 and NZW×BXSB F1) were evaluated in this study. NZW×BXSB F1 was also considered as a model of antiphospholipid syndrome (APS) since aPLs were detected with a high titer (2). Experimental SARS-CoV-2 infection was induced using mouse-passaged virus strain (3). The incidence of thromboses in the lungs and kidneys were identified by evaluating H&E staining and PTAH staining of paraffin-embedded sections. We have experienced 44 thrombotic events in 34 out of 594 patients admitted to our institute. As a non-thrombotic COVID-19, 68 patients were selected to make a 1 to 2 matched-pair based on the propensity score. In total 102 patients, seven types of aPLs (anti-cardiolipin (CL) IgG/IgM, anti-β2GP1 IgG/IgA/IgM, and anti-phosphatidyl serine/prothrombin complex (PS/PT) IgG/IgM) were measured using specific ELISA kits. The patients’ clinical characteristics and serological profile of aPLs were further evaluated.

Results

We identified the development of thromboses in the lungs or kidneys in 6 out of 12 (50%) NZW×BXSB F1 mice after the SARS-CoV-2 infection, whereas no thrombosis was observed in non-infected mice. Further, there was no thrombosis in the other lupus models (0%) after the infection. These findings might suggest the pathogenic role of aPLs under the SARS-CoV-2 infection.

Among our COVID-19 patients, 39 out of 102 (38%) were tested positive for one or more aPLs. The positive ratios of any aPLs were statistically indifferent between the patients with or without thrombosis; anti-CL IgG (8.8% vs 5.9%)/IgM (0% vs 5.9%), anti-β2GP1 IgG (21% vs 12%)/IgA (8.8% vs 15%)/IgM (0% vs 1.5%), and anti-PS/PT IgG (0% vs 2.9%)/IgM (12% vs 13%), respectively. In addition, their titers were relatively lower than those observed in APS patients. The patients’ characteristics and the prognosis of COVID-19 were comparable regardless of the detection of any aPLs. These findings suggested that COVID-19 associated aPLs were irrelevant to thrombotic complications.

Conclusion

Thromboses were induced after the infection of SARS-CoV-2 only in the APS model. However, aPLs detected in COVID-19 patients have little impact on the development of thrombosis. SARS-CoV-2 infection might have a high risk of thrombosis, especially in APS patients, as shown in the case report (4). The discrepancy of its thrombogenic effects of aPLs might be explained by the low titer of the antibody or the diversity of antibody epitope. Further analyses are required to clarify the mechanisms of aPLs production and the development of thrombosis in COVID-19.

References

[1]Oba S, et al. Arterial and Venous Thrombosis Complicated in COVID-19: A Retrospective Single-Center Analysis in Japan. Front Cardiovasc Med. 2021 Nov 19;8:767074.

[2]Hashimoto Y, et al. Anticardiolipin antibodies in NZW x BXSB F1 mice. A model of antiphospholipid syndrome. J Immunol. 1992 Aug 1;149(3):1063-8.

[3]Iwata-Yoshikawa N, et al. A lethal mouse model for evaluating vaccine-associated enhanced respiratory disease during SARS-CoV-2 infection. Sci Adv. 2022 Jan 7;8(1):eabh3827.

[4]Chidharla A, et al. A Case Report of COVID-Associated Catastrophic Antiphospholipid Syndrome Successfully Treated with Eculizumab. J Blood Med. 2021 Oct 30;12:929-933.

Disclosure of Interests

Seiya Oba: None declared, Tadashi Hosoya Speakers bureau: Janssen Pharmaceutical K.K.

Daiichi Sankyo Company, limited

Asahi Kasei Corporation

Ono pharmaceuticals

Eisai

Eli Lilly, Daisuke Kawata: None declared, Wenshi Lee: None declared, Mari Kamiya: None declared, Yoji Komiya: None declared, Hideyuki Iwai: None declared, Yuko Nukui: None declared, Shuji Tohda: None declared, Shinsuke Yasuda Speakers bureau: Abbvie,

Asahi Kasei Pharma,

Chugai Pharmaceutical,

Eisai, Eli Lilly,

GlaxoSmithKline,

Mitsubishi Tanabe Pharma,

Ono pharmaceutical,

Pfizer., Consultant of: ImmunoForge, Grant/research support from: Abbvie,

Asahi Kasei Pharma,

Chugai Pharmaceutical,

CSL Behring,

Eisai,

ImmunoForge,

Mitsubishi Tanabe Pharma,

Ono pharmaceutical

Two cases of BRAF-mutated, bulbar conjunctival melanoma, and review of the published literature

We describe two patients with BRAF-mutated melanoma of the epithelioid cell type arising from primary acquired melanosis with severe atypia of the right bulbar conjunctiva. Patient 1 was a 71-year-old Japanese man. After adjuvant cryotherapy and enucleation of the right eyeball, therapy with vemurafenib was administered for a distant metastasis to a lumbar vertebra, accompanied by erythema multiforme and two keratinous tumours. The patient died due to metastases to the liver and multiple vertebrae, despite therapy with nivolumab and combination therapy with dabrafenib plus trametinib. Patient 2 was a 72-year-old Japanese man. After adjuvant cryotherapy, periodic mitomycin C eye drops, and excision of the superficial portion of the right parotid gland and the dissection of cervical lymph nodes, he was treated with adjuvant combination therapy with dabrafenib plus trametinib. Dermatologists should be familiar with BRAF-mutated conjunctival melanoma, which is usually located on the bulbar conjunctiva and associated with more frequent distant metastasis.

Indications for partial parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve for benign tumours of the parotid gland

The aims of this study were to evaluate the efficacy of partial parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve for benign tumours of the parotid gland and to establish the indications for its use. We examined 106 consecutive patients with previously untreated benign tumours in the lower portion of the parotid gland who were treated by parotidectomy. The first group (anterograde group, n=52) consisted of those who had standard anterograde parotidectomy. The remaining patients, who underwent retrograde parotidectomy, were further divided into two groups: those in whom the upper edge of the tumour was located below the mastoid tip (below mastoid group, n=46) or those in whom it was above the mastoid tip (above mastoid group, n=8). The operating time was significantly shorter in the below mastoid group (141.2, 127.5, and 98.1minutes, respectively) as was intraoperative blood loss (41.1, 53.0, and 24.4ml, respectively), compared with the other two groups. There was a higher incidence of facial nerve dysfunction in the above mastoid group postoperatively (4/8) than in the other two groups. The results suggested that the presence of a tumour of any size located below the mastoid tip is a good indication for parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve.

Effect of calcium salt of functional monomer on bonding performance

To determine the amount of 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-calcium (MDP-Ca) salt produced through the demineralization of enamel or dentin by MDP, we designed experimental MDP-based one-step adhesives with different amounts of MDP. The null hypotheses were that (1) the amount of MDP-Ca salt produced through the demineralization of enamel was the same as that for dentin, and (2) the amounts of MDP-Ca salt have no effect on bonding performance. Increases in the amount of MDP resulted in increased amounts of MDP-Ca salt. The production amount of MDP-Ca salt of the dentin was 1.3 times higher than that of the enamel. The predominant species of the MDP and enamel reactants was a calcium hydrogen phosphate of MDP. In contrast, the dentin yielded both calcium phosphate and calcium hydrogen phosphate of MDP. Increases in the amount of MDP-Ca salt decreased both enamel and dentin bond strengths. An optimal concentration of MDP exists in one-step self-etch adhesives.

Growth of dielectric-embedded silicon nanocrystallites for light-emitting device application

Dielectric films with embedded silicon Si nanocrystallites (Si-Nc) have been recognized as promising light-emitting materials for future integrated photonics based on silicon technology. This work reports a novel method of making this kind of material by high-temperature annealing of Si-rich oxide or nitride films which gives rise to the phase separation reaction and the formation of crystalline silicon nanoclusters in the films. Various characteristics of these materials were studied in detail by using transmission electron microscope, X-ray photoelectron spectroscopy (XPS), Raman, and photoluminescence (PL). Strong transverse optical (TO) mode of Si-Nc at around 516 cm(-1) was found in the Raman spectra of the annealed dielectric films. XPS studies indicate that the Si 2p spectra could be transformed from a random bonding structure (as-deposited) to a random mixing of Si-Nc with stoichiometric oxide or nitride phase after the high-temperature annealing. The energy locations of PL were found to depend on the amount of rich Si and the annealing conditions. Longer and higher temperature annealing can result in the growth of the Si-Nc size and leads to a red-shift of PL. Direct correlation among the crystallite sizes with the PL peaks was found.

Fusion product diagnostics planned for Large Helical Device deuterium experiment

Deuterium experiment on the Large Helical Device (LHD) is now being planned at the National Institute for Fusion Science. The fusion product diagnostics systems currently considered for installation on LHD are described in this paper. The systems will include a time-resolved neutron yield monitor based on neutron gas counters, a time-integrated neutron yield monitor based on activation techniques, a multicollimator scintillation detector array for diagnosing spatial distribution of neutron emission rate, 2.5 MeV neutron spectrometer, 14 MeV neutron counter, and prompt γ-ray diagnostics.

Development of neutron spectrometer toward deuterium plasma diagnostics in LHD

Neutron spectrometer based on coincident counting of associated particles has been developed for deuterium plasma diagnostics on Large Helical Device (LHD) at the National Institute for Fusion Science. Efficient detection of 2.5 MeV neutron with high energy resolution would be achievable by coincident detection of a scattered neutron and a recoiled proton associated with an elastic scattering of incident neutron in a plastic scintillator as a radiator. The calculated neutron spectra from deuterium plasma heated by neutral beam injection indicate that the energy resolution of better than 7% is required for the spectrometer to evaluate energetic deuterium confinement. By using a prototype of the proposed spectrometer, the energy resolution of 6.3% and the detection efficiency of 3.3×10(-7) count/neutron were experimentally demonstrated for 2.5 MeV monoenergetic neutron, respectively.

Pharmacokinetics of Fluorinated 2-nitroimidazole Hypoxic Cell Radiosensitizers in Murine Peripheral Nervous Tissue

We have previously reported that KU-2285, a 2-nitroimidazole with a fluorinated N1-substituent (-CH2-CF2CONH(CH2)nOH, n = 2), was a promising hypoxic cell radiosensitizer. In this study the pharmacokinetics of KU-2285 and its related compounds (n = 3 and n = 4) were compared with those of etanidazole (a 2-nitroimidazole with an N1-substituent of -CH2CONH(CH2)nOH, n = 2) and its related compounds (n = 3 and n = 4) to assess the effects of incorporation of a CF2 group. The lipophilicity of the fluorinated compounds was higher than that of etanidazole, as measured by the octanol/water partition coefficient. As the number of CH2 groups increased, the lipophilicity of the compounds in both the KU-2285 and etanidazole series increased. The brain tissue levels of the fluorinated compounds were as low as those of the etanidazole derivatives, while the biological half-lives of the fluorinated compounds in peripheral nervous tissues were shorter than those of related non-fluorinated compounds.

Effect of miglitol, an alpha-glucosidase inhibitor, on atherogenic outcomes in balloon-injured diabetic rats

This study investigates the effects of miglitol, an alpha-glucosidase inhibitor, on the development of balloon-injured neointimal thickening in left common carotid artery, and the changes of glucose metabolism and inflammatory responses in Wistar fatty rats, an obese-hyperglycemic animal model, and their littermates, Wistar lean rats. Miglitol was orally administered at 40 mg/100 g of high-fat diet containing 45% kcal as fat to 12-week-old rats for 29 days, and age-matched rats without the agent were used as the respective controls. Balloon catheterization in the left common carotid artery was performed on day 15, and the artery was removed on day 29. Compared with the area ratio of the neointima/media in fatty rats without treatment, those in fatty rats with miglitol and lean rats without treatment were significantly decreased to 80%. The administration of miglitol significantly decreased the levels of plasma glucose, glycoalbumin and high-sensitivity C-reactive protein, and elevated the high-density lipoprotein-cholesterol level in fatty rats. These findings suggest that miglitol could be effective for the suppression of atherogenic outcomes in diabetic Wistar fatty rat, suggesting that the agent may have clinical benefits and contribute to prevent diabetic macroangiopathy.

The potyvirus associated with the dappled fruit of Passiflora edulis in Kagoshima prefecture, Japan is the third strain of the proposed new species East Asian Passiflora virus (EAPV) phylogenetically distinguished from strains of Passion fruit woodiness virus

A potyvirus (isolate IB) causing dappled or faded fruits and foliar mosaic symptoms of purple passionfruit, was found in the botanical garden of Kagoshima University, Japan. This isolate--differed in host range from isolates of Passion fruit woodiness virus (PWV)-AO, previously reported to cause "woodiness" in Japan. Isolates IB and AO had 83% amino acid identity in their coat proteins (CPs). In phylogenetic analysis, East Asian isolates IB, AO, and PWV-Taiwan clustered together, and were distinguishable from Australian PWV and Brazilian Cowpea aphid-borne mosaic virus isolates, which also cause "woodiness" in passionfruit. We propose the name "East Asian Passiflora virus (EAPV)" for the new potyvirus species.

Isolation of equine herpesvirus-1 lacking glycoprotein C from a dead neonatal foal in Japan

We isolated a variant equine herpesvirus-1 (EHV-1), strain 5089, from the lung of a dead neonatal foal in Japan and characterized the biological nature of the virus. The virus spread in cultured cells mainly by cell-to-cell infection, unlike wild-type EHV-1, which spreads efficiently as a cell-free virus. The virus titer in cultured supernatant and the intracellular virus titer were low compared to those of wild-type EHV-1. Heparin treatment of the virus had no effect on viral infectivity in cell culture. Glycoprotein C (gC) was not detected by Western blotting and fluorescent antibody tests in 5089 virions and 5089-infected cells, respectively. RT-PCR analysis revealed that the expression level of 5089 gC mRNA was reduced considerably compared to that of wild-type EHV-1. Sequencing analysis of the 5089 gC coding region showed a point mutation in the promoter region of the gC open reading frame. However, the mutation did not affect the promoter activity. These results suggested that the lack of gC in 5089 virions might be one of the reasons for spread of the virus by cell-to-cell infection and that gC mRNA expression might not be activated efficiently due to factors other than the mutation in the gC promoter region.

Experimental vertical transmission of Borna disease virus in the mouse

We demonstrated the experimental vertical transmission of Borna disease virus (BDV) in pregnant BALB/c mice. Giessen strain He/80 of BDV was used in the present study. Six six-week-old mice were inoculated intraperitoneally with 10(5) 50% tissue culture infective doses (TCID50), and were bred immediately. Four pregnant mice were sacrificed under anaesthesia on the 10th and 14th days after vaginal plug formation. Nine newborns from two maternal mice were sacrificed under anaesthesia on the 7th day after birth. Positive signals with RT-nested PCR techniques for BDV p24-RNAs were seen in the fetuses, placentas and brains of all newborn mice. No immunopositivities for BDV p40 were found in the fetuses or placentas at 10 days' gestation. BDV p40 immunopositivities were found in neurons of the fetal brains and in decidual cells of the placentas at 14 days' gestation. They were also found in neurons of the brains of newborn mice. At 10 days' gestation, no positive signals for BDV p40 sense or antisense riboprobes were seen in the fetal brains or placentas. Positive signals were found in neurons of the fetal brains and decidual cells of the placentas at 14 days' gestation. Positive signals for BDV p40 sense and antisense riboprobes were found in almost all neurons throughout the brains of nine newborn mice. These results suggest that persistent infection with BDV in newborn mice may be induced by vertical transmission during gestation.