Effect of aluminium ion on bioavailability of levofloxacin following oral administration of cilexetil ester of levofloxacin as prodrug in rats

A prodrug of levofloxacin (LVFX), cilexetil ester of LVFX (LVFX-CLX), was synthesized to examine whether the prodrug can avoid chelate formation with metal cations in the gastrointestinal tract. LVFX-CLX exhibited a 10-times higher partition coefficient than LVFX. In vitro, LVFX was precipitated by 76.1% in the presence of a 10-times higher concentration of aluminium chloride (Al³⁺), but LVFX-CLX was not. LVFX-CLX was rapidly hydrolyzed enzymatically by rat plasma, intestinal mucosal and liver homogenates at 37 °C, but not by pancreatic enzymes and luminal fluid. The minimum inhibitory concentration values of LVFX-CLX against S. aureus, E. coli and P. aeruginosa were far higher than that of LVFX. In rats, area under the plasma concentration-time curve from zero to 4 h (AUC_0-4h) of LVFX after oral administration of LVFX-CLX was 1.34-fold higher than that after LVFX, though it did not reach significance level. Co-administration of Al³⁺ with LVFX and LVFX-CLX in rats decreased AUC_0-4h of plasma LVFX by 75% and 60%, respectively, however, the AUC_0-4h of plasma LVFX after co-administration of LVFX-CLX and Al³⁺ was 2.2-times higher than that after co-administration of LVFX and Al³⁺. These results suggested that the use of LVFX-CLX may reduce the modulation of intestinal microflora caused by LVFX and the suppressive effect of Al³⁺ on intestinal absorption of LVFX.

Analysis of Patient Outcome after Non-curative Resection for Hepatocellular Carcinoma Using Nationwide Survey Data in Japan

BACKGROUND

Non-curative (debulking) hepatic resection for hepatocellular carcinoma (HCC) is occasionally applied for selected cases with bulky tumors or for oncologic emergency cases; however, the clinical usefulness of this procedure has not yet been fully evaluated. The aim of the present study was to evaluate the patient outcomes of non-curative hepatic resections for HCC using data from bi-annual nationwide surveys conducted in Japan.

METHOD

Data of 1084 non-curative hepatic resections for HCC were collected. The patient outcomes were compared with those of curative resections, transcatheter arterial chemoembolization (TACE), and hepatic arterial infusion chemotherapy (HAIC).

RESULTS

Patient survival after the non-curative resection was poorer than that after curative resection (P < 0.001) and was especially dismal in cases with extrahepatic tumor spread (lymph node metastasis, peritoneal seeding, or distant metastasis). As compared to cases receiving TACE without surgery, non-curative resections for multiple intrahepatic tumors were applied to cases with advanced tumors with good liver functional reserve. The survival outcomes were significantly more favorable in the TACE group, but the results became similar after propensity score matching of the patients. The survival outcome of patients receiving non-curative resections was better than that of cases treated by HAIC, with median survival times of 26.0 months and 10.0 months, respectively.

CONCLUSION

The indications for non-curative hepatic resection in patients with HCC should be judged cautiously, especially in patients with extrahepatic tumor spread. This treatment approach may be beneficial for selected patients with intermediate- or advanced-stage HCC limited in liver and with good liver functional reserve.

Automatic classification between COVID-19 pneumonia, non-COVID-19 pneumonia, and the healthy on chest X-ray image: combination of data augmentation methods

This study aimed to develop and validate computer-aided diagnosis (CXDx) system for classification between COVID-19 pneumonia, non-COVID-19 pneumonia, and the healthy on chest X-ray (CXR) images. From two public datasets, 1248 CXR images were obtained, which included 215, 533, and 500 CXR images of COVID-19 pneumonia patients, non-COVID-19 pneumonia patients, and the healthy samples, respectively. The proposed CADx system utilized VGG16 as a pre-trained model and combination of conventional method and mixup as data augmentation methods. Other types of pre-trained models were compared with the VGG16-based model. Single type or no data augmentation methods were also evaluated. Splitting of training/validation/test sets was used when building and evaluating the CADx system. Three-category accuracy was evaluated for test set with 125 CXR images. The three-category accuracy of the CAD system was 83.6% between COVID-19 pneumonia, non-COVID-19 pneumonia, and the healthy. Sensitivity for COVID-19 pneumonia was more than 90%. The combination of conventional method and mixup was more useful than single type or no data augmentation method. In conclusion, this study was able to create an accurate CADx system for the 3-category classification. Source code of our CADx system is available as open source for COVID-19 research.

Predictive factors of truncation artifacts in the arterial phase of Gd-EOB-DTPA-enhanced MRI: a nationwide multicenter study

PURPOSE

To identify predictive factors for truncation artifacts (TAs) in the arterial phase of Gd-EOB-DTPA-enhanced MRI in a multicenter study in Japan.

MATERIALS AND METHODS

Data on patient factors (age, sex, weight, presence of viral hepatitis, and other conditions) and imaging parameters (e.g., triggering, voxel size, matrix, k-space ordering, acquisition time, reduction factor, flip angle, fat suppression, field strength, injection rate, and saline volume) were obtained. Univariate and multivariate analyses were performed to investigate the correlation of these parameters.

RESULTS

We evaluated 1444 patients from 43 institutions who were scanned using GE, Siemens, Philips, or Toshiba MRI equipment (501, 354, 349, and 240 patients, respectively). The total incidence of TAs was 12.5% (17.2, 3.6, 15.7, and 12.1%, respectively). The matrix [odds ratio (OR) 0.13], flip angle (OR 5.77), use of fat suppression (OR 0.106), and field strength (OR 0.092) used in the Philips equipment significantly increased the incidence of TAs in MRI examination.

CONCLUSIONS

The incidence of TAs in the arterial phase is influenced by several patient factors and imaging parameters. Especially, Siemens and Toshiba equipment had a significantly lower frequency of TAs. This indicates that such vendor-specific technology used in the dynamic sequence may have a TA-resistant effect.

Assessment of lenvatinib treatment for unresectable hepatocellular carcinoma with liver cirrhosis

BACKGROUND

The present study aimed to assess the clinical features of patients who received lenvatinib treatment for unresectable hepatocellular carcinoma (HCC).

METHODS

The clinical characteristics, adverse events, and radiological responses were evaluated for 51 consecutive patients.

RESULTS

Of the study subjects, 37 patients had Child-Pugh class A (CPA) liver function, and 14 patients had Child-Pugh class B (CPB) liver function. The overall response rates in the CPA and CPB groups were 42.9% and 25.0%, respectively, and disease control rates were 82.9% and 83.3%, respectively, without significant difference (p = 0.2621 and 0.9697). There was no significant difference between CPA and CPB groups regarding the incidence of adverse events, except for hepatic coma. No significant difference was observed in the relative dose intensity between the CPA and CPB groups, for the first month, 1-2 months, or 2-3 months (p = 0.2368, 0.9368, and 0.9293).

CONCLUSION

The comparable outcomes between the CPA and CPB groups suggest the acceptability of lenvatinib treatment in patients with impaired liver function, at least in the acute phase. With careful follow-up, the dose can be relatively intensified, even in patients with impaired liver function and this may contribute to offering comparable treatment.

Enhanced Release of Glucose Into the Intraluminal Space of the Intestine Associated With Metformin Treatment as Revealed by [18F]Fluorodeoxyglucose PET-MRI

OBJECTIVE

Positron emission tomography (PET)-computed tomography has revealed that metformin promotes the intestinal accumulation of [¹⁸F]fluorodeoxyglucose (FDG), a nonmetabolizable glucose derivative. It has remained unknown, however, whether this accumulation occurs in the wall or intraluminal space of the intestine. We here addressed this question with the use of [¹⁸F]FDG PET-MRI, a recently developed imaging method with increased accuracy of registration and high soft-tissue contrast.

RESEARCH DESIGN AND METHODS

Among 244 individuals with type 2 diabetes who underwent PET-MRI, we extracted 24 pairs of subjects matched for age, BMI, and HbA_1c level who were receiving treatment with metformin (metformin group) or were not (control group). We evaluated accumulation of [¹⁸F]FDG in different portions of the intestine with both a visual scale and measurement of maximum standardized uptake value (SUV_max), and such accumulation within the intestinal wall or lumen was discriminated on the basis of SUV_max.

RESULTS

SUV_max of the jejunum, ileum, and right or left hemicolon was greater in the metformin group than in the control group. [¹⁸F]FDG accumulation in the ileum and right or left hemicolon, as assessed with the visual scale, was also greater in the metformin group. SUV_max for the intraluminal space of the ileum and right or left hemicolon, but not that for the intestinal wall, was greater in the metformin group than in the control group.

CONCLUSIONS

Metformin treatment was associated with increased accumulation of [¹⁸F]FDG in the intraluminal space of the intestine, suggesting that this drug promotes the transport of glucose from the circulation into stool.

Erratum: Evolution of π^{0} Suppression in Au+Au Collisions from sqrt[s_{NN}]=39 to 200 GeV [Phys. Rev. Lett. 109, 152301 (2012)]

This corrects the article DOI: 10.1103/PhysRevLett.109.152301.

Characteristics of MR Imaging for Staging and Survival Analysis of Neuroendocrine Carcinoma of the Endometrium: A Multicenter Study in Japan

Purpose:

This study aimed to examine MRI features and staging of neuroendocrine carcinoma (NEC) of the endometrium and evaluate survival.

Methods:

Clinical data, pathological, and preoperative pelvic MRI findings in 22 patients with histologically surgery-proven endometrial NEC were retrospectively reviewed. Tumors were pure NEC (n = 10) or mixed histotype (n = 12), with 13 large and nine small cell type.

Results:

International Federation of Gynecology and Obstetrics (FIGO) staging was I, II, III, and IV in 6, 2, 12, and 2 patients, respectively. In 13 (76.4%) of 17 patients with pathological deep myometrial invasion, MRI showed abnormal diffusely infiltrative high T₂ signal intensity throughout the myometrium with loss of normal uterine architecture. All tumors had restricted diffusion (apparent diffusion coefficient map low signal intensity, diffusion weighted imaging high signal intensity). Accuracy of T staging by MRI for all cases was 81.8%, with reference to pathology staging, while patient-based sensitivity, specificity, and accuracy for detecting metastatic pelvic lymph nodes was 60.0%, 100%, and 77.8%, respectively. Two intrapelvic peritoneal dissemination cases were detected by MRI. During follow-up (mean 30.4, range 3.3–138.4 months), 16 patients (72.7%) experienced recurrence and 12 (54.5%) died of disease. Two-year disease-free and overall survival rates for FIGO I, II, III, and IV were 66.7% and 83.3%, 50% and 100%, 10% and 33.3%, and 0% and 0%, respectively.

Conclusion:

Abnormal diffusely infiltrative high T₂ signal intensity throughout the myometrium with normal uterine architecture loss and obvious restricted diffusion throughout the tumor are suggestive features of endometrial NEC. Pelvic MRI is reliable for intrapelvic staging of affected patients.

Halo Structure of the Neutron-Dripline Nucleus ^{19}B

The heaviest bound isotope of boron ^{19}B has been investigated using exclusive measurements of its Coulomb dissociation, into ^{17}B and two neutrons, in collisions with Pb at 220  MeV/nucleon. Enhanced electric dipole (E1) strength is observed just above the two-neutron decay threshold with an integrated E1 strength of B(E1)=1.64±0.06(stat)±0.12(sys)  e^{2} fm^{2} for relative energies below 6 MeV. This feature, known as a soft E1 excitation, provides the first firm evidence that ^{19}B has a prominent two-neutron halo. Three-body calculations that reproduce the energy spectrum indicate that the valence neutrons have a significant s-wave configuration and exhibit a dineutronlike correlation.

Evaluation of a high-speed but low-throughput RT-qPCR system for detection of SARS-CoV-2

With the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), a high-speed and convenient detection technology should be at the forefront of medical care worldwide. This study evaluated the usefulness of GeneSoC, a compact, high-speed reciprocal flow quantitative reverse transcription polymerase chain reaction system, for the detection of SARS-CoV-2. The results support the use of this system for the rapid identification of SARS-CoV-2. This approach can contribute to the strategic selection of initial management strategies for patients with COVID-19.

Amyloid Signature Proteins in Feline Amyloidosis

In human amyloidoses, amyloid signature proteins (ASPs), such as serum amyloid P component (SAP) and apolipoprotein E (ApoE), are deposited in tissues together with amyloid fibrils and are implicated in the pathogenesis of amyloidosis. Few reports describe ASPs in animals. In this study, we examined feline amyloidosis and performed immunohistochemical and proteomic analyses of SAP, ApoE, apolipoprotein A-I (ApoAI) and apolipoprotein A-IV (ApoAIV). Ten cases of systemic amyloidosis, three cases of amyloid-producing odontogenic tumour and three cases of islet amyloidosis were used for immunohistochemistry (IHC) and/or proteomic analyses. IHC showed that ApoE was present in amyloid deposits in all samples. ApoAI and ApoAIV differed in the degree of co-deposition with amyloid depending on the type of amyloid and the affected organ. SAP was negative in all amyloid deposits. Proteomic analysis showed that ApoE was present in all samples, but ApoAI and ApoAIV were detected only in some samples and SAP was not detected in any samples. The observation that ApoE was detected in all types of amyloid suggests the involvement of ApoE in the development of feline amyloidosis. ASPs in feline amyloidosis are significantly different from those in human amyloidosis, suggesting that the involvement of ASPs in the pathological condition differs between animal species.

Extending the Southern Shore of the Island of Inversion to ^{28}F

Detailed spectroscopy of the neutron-unbound nucleus ^{28}F has been performed for the first time following proton/neutron removal from ^{29}Ne/^{29}F beams at energies around 230  MeV/nucleon. The invariant-mass spectra were reconstructed for both the ^{27}F^{(*)}+n and ^{26}F^{(*)}+2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the ^{28}F ground state, with S_{n}(^{28}F)=-199(6)  keV, while analysis of the 2n decay channel allowed a considerably improved S_{n}(^{27}F)=1620(60)  keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of ^{28}F. Importantly, in the case of the ground state, the reconstructed ^{27}F+n momentum distribution following neutron removal from ^{29}F indicates that it arises mainly from the 1p_{3/2} neutron intruder configuration. This demonstrates that the island of inversion around N=20 includes ^{28}F, and most probably ^{29}F, and suggests that ^{28}O is not doubly magic.

Total tumour volume as a prognostic factor in patients with resectable colorectal cancer liver metastases

Background

Although total tumour volume (TTV) may have prognostic value for hepatic resection in certain solid cancers, its importance in colorectal liver metastases (CRLM) remains unexplored. This study investigated its prognostic value in patients with resectable CRLM.

Method

This was a retrospective review of patients who underwent hepatic resection for CRLM between 2008 and 2017 in a single institution. TTV was measured from CT images using three‐dimensional construction software; cut‐off values were determined using receiver operating characteristic (ROC) curve analyses. Potential prognostic factors, overall survival (OS) and recurrence‐free survival (RFS) were determined using multivariable and Kaplan–Meier analyses.

Results

Some 94 patients were included. TTV cut‐off values for OS and RFS were 100 and 10 ml respectively. Right colonic primary tumours, primary lymph node metastasis and bilobar liver metastasis were included in the multivariable analysis of OS; a TTV of 100 ml or above was independently associated with poorer OS (hazard ratio (HR) 6·34, 95 per cent c.i. 2·08 to 17·90; P = 0·002). Right colonic primary tumours and primary lymph node metastasis were included in the RFS analysis; a TTV of 10 ml or more independently predicted poorer RFS (HR 1·90, 1·12 to 3·57; P = 0·017). The 5‐year OS rate for a TTV of 100 ml or more was 41 per cent, compared with 67 per cent for a TTV below 100 ml (P = 0·006). Corresponding RFS rates with TTV of 10 ml or more, or less than 10 ml, were 14 and 58 per cent respectively (P = 0·009). A TTV of at least 100 ml conferred a higher rate of unresectable initial recurrences (12 of 15, 80 per cent) after initial hepatic resection.

Conclusion

TTV was associated with RFS and OS after initial hepatic resection for CRLM; TTV of 100 ml or above was associated with a higher rate of unresectable recurrence.

CT angiography with 15 mL contrast material injection on time-resolved imaging for endovascular abdominal aortic aneurysm repair

PURPOSE

To assess the utility of whole-aorta CT angiography (CTA) with 15 mL contrast material (CM) on time-resolved imaging for endovascular abdominal aortic repair (EVAR).

METHODS

Twenty-six patients with a high-risk of post-contrast acute kidney injury (PC-AKI) underwent CTA with 15 mL CM using temporal maximum intensity projection (tMIP-CTA) generated from time-resolved imaging. The aortoiliac CT values were measured. Two observers measured the arterial diameters in unenhanced CT and tMIP-CTA images, and image quality was evaluated on a 5-point scale. The presence of the accessory renal artery, inferior mesenteric artery (IMA) occlusion, and instructions for use (IFU) of EVAR were evaluated.

RESULTS

CT examinations were successfully performed, and no patients developed PC-AKI. The mean CT values of the whole aorta were 267.5 ± 51.4 HU, which gradually decreased according to the distal levels of the aorta. Bland-Altman analysis revealed excellent agreement for the external arterial diameter measurements between unenhanced CT and tMIP-CTA. Excellent interobserver agreement was achieved for the measurements of the external (ICCs, 0.910-0.992) and internal arterial diameters (ICCs, 0.895-0.993). Excellent or good overall image quality was achieved in 24 (92 %) patients. The presence of the accessory renal artery, IMA occlusion and the assessment of IFU were in 100 % agreement. Multivariate analysis revealed aortic volume as the most significant independent factor associated with strong aortic enhancement (p = 0.004).

CONCLUSIONS

Whole-aorta tMIP-CTA on time-resolved imaging is useful for maintaining contrast enhancement and image quality for EVAR planning, and can substantially reduce the amount of CM.

Prediction of pancreatic atrophy after steroid therapy using equilibrium-phase contrast computed tomography imaging in autoimmune pancreatitis

Background and Aims

Imaging tools for predicting pancreatic atrophy after steroid therapy in autoimmune pancreatitis (AIP) have not been established. As delayed equilibrium‐phase contrast enhancement in computed tomography (CE‐CT) may reflect interstitial fibrosis, we evaluated the ability of equilibrium‐phase CT imaging for predicting pancreatic atrophy.

Methods

Forty‐six steroid‐treated AIP patients who underwent contrast‐enhanced CT at our university hospital were included in this retrospective study. CT attenuation (Hounsfield units [HU]) values in noncontrast images (NC) and equilibrium‐phase images (EP) and the differences in HU values between NC and EP images (SUB) were measured. Pancreatic volume was measured in CE‐CT before (Vol_pre) and after (Vol_post) steroid therapy. The volume reduction rate was calculated. The relationships of CT values with pancreatic atrophy, Vol_post, volume reduction rate, and diabetes exacerbation were investigated.

Results

CT values in the EP and SUB images before steroid therapy were associated with pancreatic atrophy after steroid therapy (atrophy vs nonatrophy 114.5 ± 12.8 vs 99.5 ± 11.1, P = 0.0002; 70.9 ± 14.72 vs 57.2 ± 13.1, P = 0.003, respectively), but CT values in NC images were not (P = 0.42). CT values in EP and SUB images before steroid therapy were correlated with Vol_post (EP images r = −0.70, P = 0.002; SUB images r = −0.68, P = 0.03) and volume reduction rate after steroid therapy (EP images: r = −0.55, P < 0.0001; SUB images r = −0.45, P = 0.002). Diabetes exacerbation was associated with higher EP and SUB values (P = 0.009 and P = 0.04, respectively).

Conclusion

Equilibrium‐phase contrast CT imaging may facilitate prediction of pancreatic atrophy after steroid therapy in AIP.

Atypical Type 2 Endoleak from an Artery Supplying the Psoas Major Muscle Following Endovascular Repair in a Case of Isolated Common Iliac Artery Aneurysm

In this report, we present a rare case of type 2 endoleak (T2EL) from an artery supplying the psoas major muscle, following an endovascular repair of a common iliac artery aneurysm (CIAA). A 79-year-old male underwent endovascular aneurysm repair (EVAR) for the right isolated CIAA using stent graft, with embolization of the ipsilateral internal iliac artery. The aneurysm was stable for 2 years, after which a follow-up CT revealed a 5 mm increase in the CIAA diameter and an endoleak of unknown origin. Conventional and CT angiographies revealed the source to be a branch from the ipsilateral deep circumflex iliac artery supplying the psoas major muscle that had developed an anastomosis at its terminal end with the vasa vasorum at the CIAA. Transarterial embolization of T2EL using glue was performed successfully, following which the T2EL disappeared.

Report of the 20th Nationwide follow-up survey of primary liver cancer in Japan

In the 20th Nationwide Follow-up Survey of Primary Liver Cancer in Japan, data from 21 075 new patients and 40 769 previously followed patients were compiled from 544 institutions over a 2-year period from 1 January 2008 to 31 December 2009. Compared with the previous 19th survey, the population of patients with hepatocellular carcinoma (HCC) was older at the time of clinical diagnosis, included more female patients, included more patients with non-B non-C HCC, had smaller tumor diameters and more frequently received radiofrequency ablation as local ablation therapy. Cumulative survival rates were calculated for HCC, intrahepatic cholangiocarcinoma, and combined hepatocellular cholangiocarcinoma (combined HCC and intrahepatic cholangiocarcinoma) by treatment type and by background characteristics for patients newly registered between 1998 and 2009 whose final outcome was survival or death. Cumulative survival rates for HCC were calculated by dividing patients by combinations of background factors (number of tumors, tumor diameter, and Child-Pugh grade) and by treatment types (hepatectomy, local ablation therapy, and transcatheter arterial chemoembolization). Cumulative survival rates and median overall survival in patients treated by resection, transcatheter arterial chemoembolization, and local ablation therapy were calculated. The same values were also calculated by the registration date by dividing patients newly registered between 1978 and 2009 into four time period groups . The results of the analysis show that the prognosis of HCC is improving dramatically. It is expected that the data obtained from this nationwide follow-up survey will contribute to advancing clinical research, including the design of clinical trials, as well as the treatment strategy of primary liver cancer in the clinical practice setting.

Sirlin C, Song B, Taouli B, Yoshimitsu K, Koh DM. Consensus report from the 8th International Forum for Liver Magnetic Resonance Imaging

OBJECTIVES

The 8th International Forum for Liver Magnetic Resonance Imaging (MRI), held in Basel, Switzerland, in October 2017, brought together clinical and academic radiologists from around the world to discuss developments in and reach consensus on key issues in the field of gadoxetic acid-enhanced liver MRI since the previous Forum held in 2013.

METHODS

Two main themes in liver MRI were considered in detail at the Forum: the use of gadoxetic acid for contrast-enhanced MRI in patients with liver cirrhosis and the technical performance of gadoxetic acid-enhanced liver MRI, both opportunities and challenges. This article summarises the expert presentations and the delegate voting on consensus statements discussed at the Forum.

RESULTS AND CONCLUSIONS

It was concluded that gadoxetic acid-enhanced MRI has higher sensitivity for the diagnosis of hepatocellular carcinoma (HCC), when compared with multidetector CT, by utilising features of hyperenhancement in the arterial phase and hypointensity in the hepatobiliary phase (HBP). Recent HCC management guidelines recognise an increasing role for gadoxetic acid-enhanced MRI in early diagnosis and monitoring post-resection. Additional research is needed to define the role of HBP in predicting microvascular invasion, to better define washout during the transitional phase in gadoxetic acid-enhanced MRI for HCC diagnosis, and to reduce the artefacts encountered in the arterial phase. Technical developments are being directed to shortening the MRI protocol for reducing time and patient discomfort and toward utilising faster imaging and non-Cartesian free-breathing approaches that have the potential to improve multiphasic dynamic imaging.

KEY POINTS

• Gadoxetic acid-enhanced MRI provides higher diagnostic sensitivity than CT for diagnosing HCC. • Gadoxetic acid-enhanced MRI has roles in early-HCC diagnosis and monitoring post-resection response. • Faster imaging and free-breathing approaches have potential to improve multiphasic dynamic imaging.

P295 Impact of Pre-existing Mitral Regurgitation on the Mid-Term Left Ventricular Mass Regression following Transcatheter Aortic Valve Implantation for Aortic Valve Stenosis

Background

Transcatheter aortic valve implantation (TAVI) results in an immediate and greater aortic pressure gradient improvement in patients with severe aortic valve stenosis (AS), and induces early left ventricular (LV) mass regression, which may be related to favorable effects on the mid to long term outcomes. However, the extent of LV mass regression after unloading of chronic pressure overload is varying, and its determinants are still unknown. Thus, the study aims to identify echocardiographic determinants of LV mass regression following TAVI.

Methods

We retrospectively screened all TAVI procedures in symptomatic AS from 2017 to 2019, and selected 74 successful TAVI cases that had serial echocardiographic studies both at the baseline and at the mid-term follow-up (4 to 6 months after the procedure). Through the digitalized medical records, clinical and echocardiographic data as well as angiographic grading (0-3) of post-procedure paravalvular leakage (PVL) were obtained. LV mass was calculated by using Cube formula. Thus, the extent of LV mass regression was defined as the differences of left ventricular mas index (LVMI) between at the baseline and at the follow-up (ΔLVMI). Quantification of the baseline mitral valve regurgitant volume was performed by stroke volume method with pulmonic site measurement on the assumption of no pre-existing intra/extra cardiac shunt. Cases with prior mitral valve replacement were excluded.

Results

At the post-procedure angiogram, only 3 cases had significant PVL (grade 2≤). At the mid-term follow–up, average LVMI decreased significantly from the baseline (165 ± 38 g/m2vs 140 ± 37 mg/ m2, P &lt; 0.0001) and 57 cases (70%) experienced the reduction of LVMI, although average relative wall thickness (2 × posterior wall thickness/left ventricular diastolic dimension) did not change (0.565 ± 0.135 vs 0.586 ± 0.168, P = 0.314). Among the baseline clinical and echocardiographic variables, the baseline peak A wave velocity, E/A ratio, mitral valve regurgitant volume and LVMI revealed simple correlation with ΔLVMI (γ=-0.298, p = 0.0188;γ=0.251, P = 0.0417;γ=0.354, p = 0.0041;γ=0.375, p &lt; 0.0010; respectively), whereas no correlation was observed in angiographic PVL grade. Stepwise multiple regression analysis demonstrated baseline mitral valve regurgitant volume and LVMI as the determinants of ΔLVMI (β=0.344, p = 0.032; β=0.335 P &lt; 0.0001; respectively).

Conclusions

Pre-existing mitral regurgitation has an impact on the mid–term left ventricular mass regression following TAVI. In severe AS, mitral regurgitation might be functioning as an afterload adjuster, and thus, produces protective effects on LV structure.

P107 Predictors of increased d-dimer level at follow-up period after transcatheter aortic valve implantation.Is oral anticoagulation therapy better?

Background

Recently, there are some reports that hypo-attenuated leaflet thickening (HALT) following transcatheter aortic valve implantation (TAVI) is incidentally detected by multi-slice computed tomography. It is believed that valve thrombosis causes HALT, because oral anticoagulation therapy (OAC) is effective for HALT regression. Furthermore, it is reported that d-dimer level increases in patients with HALT, and might be a key biomarker to detect HALT.

Purpose

We sought to investigate the predictors related to increased d-dimer level at 6 months after follow-up TAVI.

Methods

We enrolled 124 consecutive patients who underwent successful TAVI between 2016 and 2018. Study patients were classified into two groups according to antithrombotic therapy resume (OAC therapy or anti-platelet therapy).We set the primary endpoint as the d-dimer levels at 6 months after TAVI. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. Furthermore, we set the secondary endpoint as one-year bleeding event.

Results

The median age of patients was 83 years old (quartile 80-87). Patients who had taken OAC at 6 months follow-up after TAVI were 29.8%. The median d-dimer level at 6 months after TAVI was 1.3 (1.0-2.2) µg/ml, and OAC group had statistically lower d-dimer level at 6 months follow-up than those in non-OAC group (p = 0.020). Uni-variable liner regression model demonstrated that increased d-dimer level at follow-up had significant relationship with large effective orifice area (EOA) (p = 0.002) and low left ventricular ejection fraction (LVEF) (p = 0.048) after TAVI. Furthermore, large EOA (p = 0.003) and OAC therapy (p = 0.027) were independently associated with increased d-dimer level in multivariate analysis. Kaplan-Meier estimates revealed that there were no significant difference regarding one-year bleeding event between OAC group and non-OAC group (long-rank p = 0.167).

Conclusions

This study suggests that large EOA after TAVI is associated with increased d-dimer levels at 6 months after TAVI, and OAC therapy might have a potential to decrease d-dimer level after TAVI without increase of bleeding events.

Abstract P107 Figure: One-year bleeding event

Hepatic Artery Embolization Induces the Local Overexpression of Transforming Growth Factor β1 in a Rat Hepatoma Model

INTRODUCTION

The underlying mechanism involved in the recurrence of hepatoma after hepatic arterial embolization (HAE) is not adequately examined. An immunosuppressive cytokine, transforming growth factor β1 (TGF-β1), can lead to tumor progression and is affected by hypoxia in various cancers. The study aimed to assess the effect of HAE on the expression of TGF-β1 in a rat hepatoma model.

METHODS

Sprague-Dawley rats bearing N1S1 hepatoma cells underwent HAE (HAE group, n = 5) or sham treatment (sham group, n = 4). The animals were euthanized at 48 h, and liver tissues were harvested. Immunohistochemistry (IHC) and quantitative polymerase chain reaction (qPCR) were performed to compare the expression of TGF-β1 and hypoxia-inducible factor 1α (HIF-1α) between the HAE and sham groups. In vitro experiments with the N1S1 cell line were also performed under normoxic (21% O₂) or hypoxic (1% O₂) conditions for 48 h, and the expression of TGF-β1 and HIF-1α was assessed with western blotting and enzyme-linked immunosorbent assay. Statistical data comparisons were performed by Student t test.

RESULTS

IHC showed that both the TGF-β1-positive and HIF-1α-positive tumor peripheral areas were larger in the HAE group (6.59 ± 2.49 and 10.26 ± 4.14%; p < 0.001, respectively) than in the sham group (0.34 ± 0.41 and 0.40 ± 0.84% respectively). Similarly, qPCR showed that the mRNA expression levels of TGF-β1 and HIF-1α were higher (1.95 ± 0.38-fold and 1.62 ± 0.37-fold; p < 0.001 and p = 0.002, respectively) in the HAE group than those in the sham group. TGF-β1 expression was suppressed when HIF-1α inhibitors were added (p = 0.001), and HIF-1α expression was upregulated when exogenous TGF-β1 was added (p = 0.033) in N1S1 cells.

CONCLUSION

HAE enhanced local TGF-β1 expression in a rat hepatoma model. In vitro experiments suggest that HAE-induced hypoxic stress may trigger the interdependent expression of TGF-β1 and HIF-1α.