Dynamical visualization of anisotropic electromagnetic re-emissions from a single metal micro-helix at THz frequencies

The capability for actual measurements—not just simulations—of the dynamical behavior of THz electromagnetic waves, including interactions with prevalent 3D objects, has become increasingly important not only for developments of various THz devices, but also for reliable evaluation of electromagnetic compatibility. We have obtained real-time visualizations of the spatial evolution of THz electromagnetic waves interacting with a single metal micro-helix. After the micro-helix is stimulated by a broadband pico-second pulse of THz electromagnetic waves, two types of anisotropic re-emissions can occur following overall inductive current oscillations in the micro-helix. They propagate in orthogonally crossed directions with different THz frequency spectra. This unique radiative feature can be very useful for the development of a smart antenna with broadband multiplexing/demultiplexing ability and directional adaptivity. In this way, we have demonstrated that our advanced measurement techniques can lead to the development of novel functional THz devices.

The utility of a novel approach to quantify dyssynchrony by multidetector computed tomography

Funding Acknowledgements

Type of funding sources: None.

Background

Quantification of left ventricular (LV) dyssynchrony is of great interest for resynchronization therapy (CRT). Recently, cardiac computed tomography (CCT) is feasible for evaluation of dyssynchrony. Our aim was to assess a novel simplified approach using CCT to quantify LV dyssynchrony.

Methods

We studied 346 consecutive patients with a wide range of QRS width and ejection fractions (EF). Electrocardiogram-gated contrast-enhanced 256-slice multidetector CT (Brilliance 256 iCT, Philips Medical Systems) was performed before CRT. After CCT scan, the LV endocardial boundaries from short-axis images reconstructed at 5% increments of cardiac cycle were automatically detected, and a time from R-wave to maximal wall motion was calculated for each of the 16 standardized segments for all slices using software "Myocardial Contraction Map" (Argus, Inc Ehime, Japan). The standard deviation of all segments modified by mean heart rate (%SD) was respectively calculated as the global parameter of dyssynchrony. LVEF was also measured using MDCT.

Results

%SD was feasible in all patients, respectably. %SD was significantly different between the different QRS duration groups; narrow QRS (<120ms): 9 ± 5%, relatively wide QRS (120-150 ms): 11 ± 6%, and significantly wide QRS (>150 ms): 14 ± 7% (p <0.001). Moreover, there was significantly difference in %SD between the different morphology groups; normal: 9 ± 7%, Non-left bundle branch block (Non-LBBB): 10 ± 6%, LBBB: 17 ± 7% (p <0.001).

Conclusion

This novel simplified approach by CCT can quantify dyssynchrony in different QRS duration and morphology groups. This method has promise for clinical applications to the evaluation of patients for CRT.

Abstract Figure.

Association between low preoperative skeletal muscle quality and infectious complications following gastrectomy for gastric cancer

PURPOSE

It is known that sarcopenia affects the overall short- and long-term outcomes of patients with gastric cancer (GC); however, the effect of muscle quality on infectious complications after gastrectomy for GC remains unclear. We investigated the associations between the preoperative quantity and quality of skeletal muscle on infectious complications following gastrectomy for GC.

METHODS

The subjects of this retrospective study were 353 GC patients who underwent radical gastrectomy between 2009 and 2018. We examined the relationships between their clinical factors, including skeletal muscle mass index and intramuscular adipose tissue content (IMAC), and infectious complications after gastrectomy.

RESULTS

Infectious complications developed in 59 patients (16.7%). The independent risk factors for infectious complications identified by multivariate analysis were male gender (P < 0.001), prognostic nutritional index below 45 (P = 0.006), and high IMAC (P = 0.011). Patients with a high IMAC were older and had a higher body mass index, as well as a greater age-adjusted Charlson comorbidity index, than those with low or normal IMAC.

CONCLUSIONS

Low skeletal muscle quality defined by a high IMAC is a risk factor for infectious complications following gastrectomy. When feasible, preoperative nutritional intervention and rehabilitation aiming to improve muscle quality could reduce infectious complications after gastrectomy for GC.

Comparative Study of an Ultrasound-guided Percutaneous Biopsy and Endoscopic Ultrasound-guided Fine-needle Aspiration for Liver Tumors

Objective Both a percutaneous biopsy and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) have been widely performed for liver tumors. However, no studies have compared these two biopsy methods. Method A retrospective study was conducted using medical records for patients who underwent a liver tumor biopsy from 2012 to 2019. The cases were classified into two groups for a comparison: an ultrasound-guided percutaneous biopsy group (percutaneous group) and an EUS-FNA group (EUS group). Results A total of 106 patients (47 in the percutaneous group and 59 in the EUS group) were included. The final diagnosis was malignant in 100 cases and benign in the remaining 6 cases. While the median lesion diameter was 62 mm in the percutaneous group, it was significantly smaller (34 mm) in the EUS group (p <0.01). The EUS group had more left lobe tumors than right lobe tumors. All cases of caudate lobe tumor (four cases) underwent EUS-FNA. The sensitivity, specificity, and accuracy of the procedure were 95%, 100%, and 96% in the percutaneous group and 100%, 100%, and 100% in the EUS group, respectively showing no significant difference. Adverse events were reported in 17% of the percutaneous group, which was significantly lower than in the EUS group (2%; p <0.01). Conclusion A percutaneous biopsy and EUS-FNA have equivalent diagnostic qualities for liver tumors, although EUS-FNA tends to be associated with fewer adverse events. A complete understanding of the characteristics of each procedure is essential when choosing the best biopsy method for each particular case.

High incidence of left atrial dysfunction and low voltage zone in patients requiring multiple atrial fibrillation ablation

Background

While multiple catheter ablation for recurrent atrial fibrillation (AF) is effective for the maintenance of sinus rhythm, some of patients have ablation-refractory AF. Left atrial (LA) dysfunction and the presence of low voltage zone (LVZ) are associated with recurrence after AF ablation. The association between recurrence and LA dysfunction/ LVZ among patients undergoing multiple AF ablation remains unclear.

Purpose

We aimed to compare (i)LA function, (ii)the prevalence of LVZ among patients undergoing first, second and third or more AF ablation procedures. Further, we investigated whether LA dysfunction and LVZ are associated with recurrence after multiple procedures.

Methods

We retrospectively analyzed 460 patients undergoing AF ablation procedures including first, second and third or more sessions from January 2017 to October 2019 in our institute. Before each session, 256-slice MDCT was performed under sinus rhythm to measure pre-ablation LA emptying fraction (LAEF) as the representative of LA function. At the end of each session, we checked the presence of LVZ, which was defined as regions where bipolar peak-to-peak voltage was &lt;0.5mV. All patients underwent pulmonary vein isolation (PVI). If necessary, additional ablation (e.g. linear ablation, non-PV foci ablation and LVZ ablation) was performed.

Results

Out of 460 sessions, 295 were first (follow-up years: 1.5 [0.8, 2.0]), 134 were second (1.0 [0.5, 1.8]), and 31 were third or more sessions (1.2 [0.7, 2.0]). As the number of sessions increased, the recurrence rate was increased (19% vs. 31% vs. 61%, first vs. second vs. ≥third, P&lt;0.0001), LAEF decreased (39.7±10.5% vs. 32.6±10.1% vs. 25.3±11.8%, P&lt;0.0001) and the incidence of LVZ increased (18% vs. 34% vs. 68%, P&lt;0.0001) (Figure 1). In patients with recurrence (N=104) after multiple ablation (second or more sessions), LAEF was lower and the prevalence of LVZ was higher than those without recurrence (N=61) (LAEF: 27.3±10.3% vs. 33.5±10.5%, with vs. without, P=0.0003; LVZ: 57% vs. 31%, P=0.0014).

Conclusions

As the number of sessions increased, the recurrence rate was increased. The prevalence of LA dysfunction and LVZ was high in patients requiring multiple ablation procedure. LA dysfunction and LVZ possibly reflect arrhytmogenic substrate causing recurrence of ablation-refractory AF. We should carefully consider repeated AF ablation in patients with severe LA dysfunction and extensive LVZ.

Figure 1

Funding Acknowledgement

Type of funding source: None

Pre-ablation left atrial function predicts the presence of low voltage zone in patients undergoing paroxysmal atrial fibrillation ablation: OLAF-LVZ predictive score

Background

Preoperative left atrial (LA) function is associated with paroxysmal atrial fibrillation (PAF) ablation outcome. The presence of left atrial low voltage zone (LVZ) is also associated with recurrence. We hypothesized that reduced pre-ablation LA function reflects the presence of LVZ.

Purpose

We investigated the association between baseline LA function and the presence of LVZ in patients undergoing initial PAF ablation. Further, we sought to create the new predictive scoring for the presence of LVZ.

Methods

Consecutive 305 patients who underwent LA voltage mapping during initial PAF ablation from January 2017 to October 2019 in our institute were retrospectively analyzed. We performed 256-slice MDCT at baseline. As the representative of LA function, we calculated LA emptying fraction (LAEF), where LAEF = {[(maximum LAV) − (minimum LAV)]/(maximum LAV)} x 100. LVZ was defined as regions where bipolar peak-to-peak voltage was &lt;0.5mV. We performed the univariate and multivariate analysis to assess the association between LAEF and the presence of LVZ. Second, we performed receiver operating characteristic (ROC) analysis for the prediction of LVZ. We combined multivariate predictors and created the predictive scoring for LVZ.

Results

Out of 305 pts, 56 pts (18%) had LVZ in LA. In univariate analysis, low body mass index, higher percentage of female sex, higher age, higher E/e', larger maximum LA volume and lower LAEF (29.3±11.8% vs. 41.2±9.7, P&lt;0.0001) was associated with the presence of LVZ. In multivariate logistic regression analysis, Low LAEF revealed the strongest predictor for LVZ (LAEF; Odds ratio [OR]/10% increase: 0.54, 95% CI: 0.39–0.82, P=0.0016). High age and female sex also remained as the independent predictors (Age; OR/10 y.o. increase: 1.80, 1.23–3.03, P=0.0042, Female; OR: 2.51, 1.15–5.49, P=0.0213). In ROC analysis, LAEF had moderate predictive accuracy for the presence of LVZ. (Area under the ROC curve: 0.77, Best cut-off value: 31%, P&lt;0.0001) (Figure 1). We created OLAF-LVZ predictive score by combining Old age (1 point, ≥65), LAEF (2 points, LAEF ≤31%) and Female sex (1 point). OLAF score had gradient effect on the incidence of LVZ (2%, 11%, 25%, 45%, 71%, OLAF score; 0, 1, 2, 3, 4, respectively, P&lt;0.0001) (Figure 2).

Conclusions

In PAF patients, preoperative LAEF was strongly associated with the presence of LVZ. LVZ might reflect the myocardial injury causing LA dysfunction. OLAF-LVZ predictive score: combination of Old age (≥65), Female sex, and LAEF (≤31%) could be useful to stratify the risk of the presence of LVZ.

Funding Acknowledgement

Type of funding source: None

Aggressive lipid lowering therapy with pitavastatin and ezetimibe improve cardiovascular outcomes in patients with ST segment elevation myocardial infarction: insights from the HIJ-PROPER Study

Aims

The purpose of this study was to evaluate the effect of aggressive lipid-lowering therapy with pitavastatin and ezetimibe in patients with ST-segment elevation myocardial infarction (STEMI) as compared with those with other classification of an acute coronary syndrome (ACS) including non-STEMI (NSTEMI) and unstable angina pectoris (UA).

Methods

This is a post hoc sub-analysis of the HIJ-PROPER study. In the original study, ACS patients with dyslipidemia were randomized to either pitavastatin + ezetimibe therapy or pitavastatin monotherapy. In the present analysis, we divided HIJ-PROPER participants into the STEMI group (n=880) and NSTEMI + UA group (n=841). Cardiovascular events were analyzed between the two groups. The primary endpoint was a composite of major advanced cardiovascular events (MACE; all-cause death, non-fatal myocardial infarction, non-fatal stroke, unstable angina pectoris, and ischemia-driven revascularization)

Result

During median follow-up period of 3.4 years, the cumulative incidence of the primary endpoint in STEMI group was 31.9% in the pitavastatin+ezetimibe therapy, compared with 39.7% in the pitavastatin-monotherapy (HR, 0.77; 95% CI, 0.62–0.97; p=0.02). However, there was no effect of pitavastatin+ezetimibe therapy on the primary endpoint in the NSTEMI + UA group. Concerning the individual components of the primary endpoint in STEMI group, the percentage of occurrence of all-cause death was significantly lower in the pitavastatin+ezetimibe therapy compared to pitavastatin mono-therapy (14 patients (3.2%) vs. 31 patients (6.9%), respectively; HR, 0.45; 95% CI, 0.23–1.84, p=0.01). Multivariate analysis revealed that use of ezetimibe and prevalence of diabetes mellitus at baseline were independent predictors of primary endpoints in STEMI group (HR, 0.79; 95% CI, 0.63–0.99; p=0.04 for use of ezetimibe, HR 1.54; 95% CI, 1.22–1.94, p=0.0003 for diabetes mellitus).

Conclusion

Patients with pitavastatin+ezetimibe therapy as compared with pitavastatin-monotherapy had lower cardiovascular event in patients with ST-segment elevation myocardial infarction.

Kaplan-Meier curves for primary endpoint

Funding Acknowledgement

Type of funding source: None

Quantitative analysis of dyssynchrony assessed by multidetector computed tomography can predict clinical outcome after cardiac resynchronization therapy

Background

The degree of mechanical dyssynchrony has been suggested as a predictor for long-term survival after cardiac resynchronization therapy (CRT). There have been little reports of dyssynchrony assessment with the use of cardiac computed tomography (CCT).

Methods

We studied 35 heart failure (HF) patients (average age 67±10 years) referred for CRT with NYHA III-IV heart failure, left ventricular (LV) ejection fraction (EF) 20±10% (all ≤35%), and QRS duration 156±22 ms (all ≥120ms). Electrocardiogram-gated contrast-enhanced 256-slice multidetector CT was performed before CRT. Based on CCT, the LV endocardial boundaries from short-axis images reconstructed at 5% increments of cardiac cycle were automatically detected, and the time from R-wave to maximal wall motion was calculated for each of the 16 standardized segments for all slices using software “Myocardial Contraction Map”. The standard deviation modified by mean heart rate (%SD) was respectively calculated as the global parameter of dyssynchrony. LVEF was also measured using MDCT. The predefined primary end-point was the first HF hospitalization or death over 2 years.

Results

%SD was feasible in all patients, respectably. There were 16 events over 2 years; 11 HF hospitalizations and 5 deaths. Patients with %SD ≥22% (optimal cutoff for outcome by ROC curve analysis) had a better clinical outcome than patients with %SD &lt;22% (p=0.01, Figure).

Conclusion

Patients who had %SD ≥22% assessed by MDCT had a particularly favorable event-free survival following CRT, and this appears to be an important prognostic marker.

Funding Acknowledgement

Type of funding source: None

Evaluation of the local atrial function by regional speckle tracking imaging using intracardiac echocardiography

Background

It has been reported that low voltage areas and conduction abnormalities detected by electrophysiology catheters in the left atrium (LA) represent regional degeneration and fibrosis of the atrium and are related to a poor atrial fibrillation (AF) ablation outcome. Assessment of the local atrial function is clinically useful because atrial degeneration does not occur uniformly throughout the atrium. Though evaluating the global atrial function using speckle tracking imaging (STI) by transthoracic echocardiography (TTE) has been attempted, TTE does not have a sufficient image quality to assess local atrial STI.

Purpose

To evaluate the local atrial function by STI using intracardiac echocardiography (ICE) and to elucidate the characteristics of the STI in normal and abnormal voltage regions in the LA.

Methods

We included 9 patients undergoing AF ablation with written informed consent for this prospective observational study. After pulmonary vein isolation, we performed voltage mapping of the LA in sinus rhythm using a CARTO system (Biosense). Abnormal regions and normal regions were defined as those with low voltage areas (&lt;0.5 mV) and those with normal voltages, respectively. Echo images were recorded by an ACUSON SC2000 (Siemens) and SOUNDSTAR catheter (Biosense). We inserted the SOUNDSTAR catheter into the LA to obtain clear images, recorded the STI of the anterior and inferior wall, and performed an offline analysis of the atrial strain with an eSie VVI work station (Siemens) and the LA voltage data with CARTO system at each site simultaneously (left figure). We compared the strain during the atrial contraction phase (Sct) between the normal and abnormal regions.

Results

Among the study population, 5 patients had low voltage areas in the LA. We evaluated the STI at 26 normal regions and 44 abnormal regions. The typical regional speckle tracking waveform in the normal region was similar to a jugular vein pressure waveform (right figure). There was a difference in the amplitude of the Sct between the groups; it was significantly smaller in the abnormal regions (normal and abnormal regions, 9.8±5.0% and 5.6±3.8%, p=0.0001). The duration of the Sct was significantly more prolonged in the abnormal regions than normal regions (98.8±26.3ms and 118.2±33.9ms, p=0.015).

Conclusions

This pilot study demonstrated that the local atrial function was evaluable by STI using ICE and that the regional strain tracking waveform during the atrial contraction phase in abnormal voltage regions was smaller and more prolonged than that in normal regions. An evaluation of the regional STI with an ICE may be useful to detect regional abnormalities of the atrium.

Representative case

Funding Acknowledgement

Type of funding source: None

Screening for obstructive sleep apnea in atrial fibrillation patients at their home before catheter ablation using watch peripheral arterial tonometry

Background

Catheter ablation of atrial fibrillation (AF) is effective, but certain patients experience AF recurrences. Obstructive sleep apnea (OSA) is a risk factor for AF recurrence. Watch peripheral arterial tonometry (WP) has a good correlation with polysomnography (PSG) in terms of the apnea-hypopnea index (AHI) and is easier to perform than PSG. Patients in AF have a high prevalence of OSA. Whether all patients with AF should be evaluated for OSA before catheter ablation is still controversial.

Purpose

To elucidate the prevalence and predictors of OSA using WP as a home sleep apnea test in AF patients before catheter ablation.

Methods

This study was conducted under a retrospective, single-center, observational design. Patients who received AF ablation without a prior diagnosis of sleep apnea and assessment of their AHI using WP were included in this analysis. The patients were mounted with a WP device by themselves at their own home. Twenty-two patients who were already diagnosed with OSA were excluded.

Results

Seven hundred seventy-four (65±11 years, 567 males, 440 paroxysmal AF) out of 776 patients were successfully mounted with WP devices on their own and underwent an OSA assessment. Their mean body mass index (BMI) was 24.1±3.5 kg/m2. The mean AHI was 20.1±15.6. Only 88 (11.4%) patients had a normal AHI (AHI&lt;5). Mild OSA (5≤AHI&lt;15), moderate OSA (15≤AHI&lt;30), and severe OSA (AHI≥30) were observed in 274 (35.4%), 252 (32.6%), and 160 (20.7%) patients, respectively. A BMI≥25 (odds ratio [OR]; 2.42, 95% confidence interval [CI]; 1.74–3.37, p&lt;0.001), male sex (1.70, 1.19–2.44, p=0.0037), non-paroxysmal AF (1.90, 1.35–2.66, p=0.0002), hypertension (1.70, 1.24–2.33, p=0.009), and left atrial volume index ≥30 (OR=1.51, CI 1.06–2.16, p=0.022) were significant predictors of moderate or severe OSA by a multivariate analysis, while an Epworth sleepiness scale ≥11 was not a predictor of moderate or severe OSA (OR=0.99, CI 0.66–1.49, p=0.95). However, 44.2% of non-obese patients (BMI &lt;25) had moderate-severe OSA.

Conclusion Almost

All patients successfully underwent WP to diagnose OSA. AF patients had a high prevalence of OSA, and screening OSA would be important in AF patients receiving ablation even if patients do not have sleepiness or are obese. We cannot deny OSA in AF patients before catheter ablation without performing screening tests for OSA.

Funding Acknowledgement

Type of funding source: None

Sex differences in the predictors of recurrent atrial fibrillation after catheter ablation: insights from the Kansai Plus Atrial Fibrillation (KPAF) registry

Background

The impact of sex differences on the clinical outcomes of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) is controversial. We previously reported that females experienced more frequent AF recurrences than males after the index and last RFCA procedures.

Purpose

To identify the risk factors associated with recurrent AF in females and males after RFCA of AF.

Methods

We conducted a large-scale, prospective, multicenter, observational study (Kansai Plus Atrial Fibrillation Registry). We enrolled 5010 consecutive patients who underwent an initial RFCA of AF at 26 centers (64±10 years; 1369 [27.3%] females; non-paroxysmal AF, 35.7%). The median follow-up duration was 2.9 years.

Results

The incidence of AF recurrences after a single procedure was 43.3% in females and 39.0% in males. After a multivariate adjustment at baseline, the significant predictors of AF recurrence in females after the index RFCA were non-paroxysmal AF (hazard ration [HR],1.59; 95% confidence interval [CI],1.31–1.93, p&lt;0.0001), a history of AF ≥2 years (HR,1.47; 95% CI,1.24–1.74, p&lt;0.0001), coronary artery disease (HR,1.43; 95% CI,1.03–1.98, p=0.0035), and an estimated glomerular filtration rate (eGFR)&lt;60 mL/min/1.73m2 (HR,1.46; 95% CI,1.10–1.95, p=0.0086). On the other hand, significant predictors of AF recurrence in males after the index RFCA were non-paroxysmal AF (HR,1.54; 95% CI,1.37–1.73, p&lt;0.0001), a history of AF ≥2 years (HR,1.40; 95% CI,1.26–1.56, p&lt;0.0001), the number of antiarrhythmic drugs (HR,1.06; 95% CI,1.003–1.13, p=0.040), a left atrial diameter≥40mm (HR,1.13; 95% CI,1.007–1.27, p=0.038), and dilated cardiomyopathy (HR,1.55; 95% CI,1.07–2.26, p=0.021), however, an eGFR&lt;60 mL/min/1.73m2 was not associated with AF recurrence in males (HR, 1.00; 95% CI, 0.88–1.13, p=0.97).

Conclusion

The Kansai Plus Atrial Fibrillation Registry revealed a distinct sex difference in terms of the predictors of recurrent AF after RFCA. Non-Paroxysmal AF and a long history of AF were common risk factors both in females and males. However, renal dysfunction was a significant predictor of AF recurrence in females, while it was not a risk of recurrence in males.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Research Institute for Production Development in Kyoto, Japan.

[Long-Term Follow-Up of Patients Who Received Chemotherapy with S-1 and Docetaxel after Relatively Curative Surgery for Advanced Gastric Cancer Including Non-Curative Factors]

There is no known recommended chemotherapy after radical surgery for gastric cancer for patients who have non-curative disease. We defined positive peritoneal cytology(CY1), resection margin involvement, pathological peritoneal metastasis (pP1)and pN3b as clinical non-curative factors and administered adjuvant chemotherapy with S-1 and docetaxel(DOC) (80 mg/m2 day 1-14 of S-1 for 2 weeks with 40 mg/m2 of DOC on day 1, every 3 weeks). This regimen lasted for 1 year; however, if chemotherapy could be continued after this period, we used S-1 only. We reported the results of 11 cases who received this treatment.

PATIENTS

There were 6 total gastrectomies and 5 distal gastrectomies. Clinical non-curative factors were 5 pP1, 5 pN3b, 3 CY1 and 1 resection margin involvement.

RESULTS

At the end of adjuvant therapy there were 6 completions, 4 recurrences, and 1 patient with side effects. The main adverse event of Grade 3 or greater was neutropenia (46%). The recurrence rate was 63.6%. Types of relapse included 6 disseminations and 1 patient with lymph node involvement. One-, 3-, and 5-year survival rates were 100%, 72.7% and 72.7%, respectively, and the RFS was 64.0 months.

CONCLUSION

S-1 and DOC adjuvant chemotherapy produced good results and may serve as a therapy of choice for patients with advanced gastric cancer with non-curative factors after a relatively curative resection.

Transient ischemic attack without self-awareness of symptoms witnessed by bystanders: analysis of the PROMISE-TIA registry

Background and purpose

A transient ischemic attack (TIA) can occur without self‐awareness of symptoms. We aimed to investigate characteristics of patients with a tissue‐based diagnosis of TIA but having no self‐awareness of their symptoms and whose symptoms were witnessed by bystanders.

Methods

We used data from the multicenter registry of 1414 patients with a clinical diagnosis of TIA. For patients without evidence of ischemic lesions on imaging, clinical characteristics were compared between patients with and without self‐awareness of their TIA symptoms.

Results

Among 896 patients (559 men, median age of 70 years), 59 (6.6%) were unaware of their TIA symptoms, but had those symptoms witnessed by bystanders. Patients without self‐awareness of symptoms were older and more frequently female, and more likely to have previous history of stroke, premorbid disability, and atrial fibrillation, but less likely to have dyslipidemia than those with self‐awareness. Patients without self‐awareness of symptoms arrive at hospitals earlier than those with self‐awareness (P < 0.001). ABCD² score was higher in patients without self‐awareness of symptoms than those with self‐awareness (median 5 vs. 4, P = 0.002). Having no self‐awareness of symptoms was a significant predictor of ischemic stroke within 1 year after adjustment for sex, ABCD² score, and onset to arrival time (hazard ratio = 2.44, 95% confidential interval: 1.10–4.83), but was not significant after further adjustment for arterial stenosis or occlusion.

Conclusions

Patients with a TIA but having no self‐awareness of their symptoms might have higher risk of subsequent ischemic stroke rather than those with self‐awareness, suggesting urgent management is needed even if patients have no self‐awareness of symptoms.

Can the location of the mural nodule indicate benign or malignant in branch duct-type intraductal papillary mucinous neoplasm of the pancreas?

BACKGROUND/OBJECTIVES

Intraductal papillary mucinous neoplasms (IPMNs) are classified into main duct (MD)-type IPMNs, branch duct (BD)-type IPMNs, and mixed type IPMNs. While MD-type IPMN has a high risk of malignancy and should therefore be considered for resection if the patient is fit, BD-type IPMN needs to be carefully judged for surgical indication. The decision to resect BD-type IPMN is often based on international consensus Fukuoka guidelines 2017, but further investigation is required. In this study, we focused on whether the location of the mural nodule (MN) could be an indicator of malignancy.

METHODS

We enrolled 17 cases who had been diagnosed BD-type IPMNs which were surgically resected from January 2016 to December 2019. These cases were classified into benign and malignant group. Subsequently, a clinicopathological study was conducted based on the localization of MN (MN-central type or MN-peripheral type).

RESULTS

Although MN was found in 57% (4/11) in the benign group, 88% (7/8) was noted in the malignant group, indicating the presence of MN to be more common in the malignant group. Those with MN consisted of 6 cases of MN-central type and 5 cases of MN-peripheral type. All cases of central type were malignant compared to only one case of the peripheral group being confirmed on histology as cancer.

CONCLUSION

BD-IPMN with central mural nodule should be considered high risk for malignancy.

Body composition as reflected by intramuscular adipose tissue content may influence short- and long-term outcome following 2-stage liver resection for colorectal liver metastases

INTRODUCTION

For many kinds of cancer, body composition and immunonutritional status have been reported to influence postoperative outcome. We assessed their impact on short- and long-term outcome in patients with colorectal liver metastases who underwent 2-stage liver resections.

METHODS

Short- and long-term outcomes for 47 patients with 2-stage hepatectomies were assessed retrospectively in terms of data obtained before preoperative chemotherapy, before the first hepatectomy, and before the second hepatectomy.

RESULTS

Although immunonutritional status and body composition did not affect short-term outcome, high intramuscular fat content before the second hepatectomy was a poor prognostic factor for overall survival (HR, 5.829; 95% CI, 1.611-21.090; p = 0.007) and for recurrence-free survival (HR, 2.787; 95% CI, 1.301-5.973; p = 0.008). Patients with high intramuscular fat before the second hepatectomy also showed shorter intervals from recurrence to treatment failure.

CONCLUSION

Intramuscular fat before the second hepatectomy is an important negative prognosticator in 2-stage liver resection for colorectal liver metastases.

Liver regeneration after performing associating liver partition and portal vein occlusion for staged hepatectomy (ALPPS) is histologically similar to that occurring after liver transplantation using a small-for-size graft

PURPOSE

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) can achieve marked future liver remnant (FLR) hypertrophy but this procedure is associated with a risk of mortality due to liver failure because of an insufficient FLR functional increase, a situation comparable to small-for-size syndrome (SFSS) after living-donor liver transplantation (LDLT).

METHODS

The clinical data, morphologic volume changes, and histopathologic and immunohistochemical findings in hepatocytes and bile ductules were compared between ALPPS (n = 10) and LDLT with a risk for SFSS (n = 12).

RESULTS

Although the patient characteristics and short-term outcome differed between the groups, the mean hypertrophy ratios with respect to liver volume for the FLR after performing the first-stage ALPPS procedures resembled those in small-for-size grafts after similar time intervals: 1.702 ± 0.407 in ALPPS vs. 1.948 ± 0.252 in LDLT (P = 0.205). The histologic grades for sinusoidal dilation (P = 0.896), congestion (P = 0.922), vacuolar change (P = 0.964), hepatocanalicular cholestasis (P = 0.969), and ductular reaction (P = 0.728) within the FLR at the second-stage operation during ALPPS or implanted graft were all similar between the groups.

CONCLUSIONS

The hepatic regenerative process may be similar in ALPPS and LDLT using a small-for-size graft. Reducing the hepatic vascular inflow that may be excessive for the FLR volume during the first stage of ALPPS might enhance the functional recovery since measures with a similar effect appear to lessen the likelihood of SFSS.

A case of pancreatic mixed acinar-neuroendocrine carcinoma successfully diagnosed with endoscopic ultrasound-guided fine needle aspiration

Mixed acinar-neuroendocrine carcinoma (MAEC) of the pancreas is a rare entity, and obtaining a preoperative diagnosis is difficult. We report a case of pancreatic MAEC successfully diagnosed with EUS-FNA. The case was a 72-year-old male with upper abdominal pain. Abdominal CT showed an irregular, hypovascular tumor of pancreatic tail. EUS-FNA was performed using a 22G needle. Immunostaining revealed positive results for the acinar marker trypsin and the neuroendocrine markers chromogranin A and synaptophysin. The possibility for MAEC was considered. He underwent distal pancreatectomy and splenectomy. Immunohistochemical examination of the tumor cells showed a wide range of positivity for bcl-10 and trypsin as well as for chromogranin A and synaptophysin, but negative results for CA19-9 and AFP. Considering that ≥ 30% tumors were positive for both acinar and neuroendocrine markers, the patient was diagnosed with MAEC.

Devil's staircase transition of the electronic structures in CeSb

Solids with competing interactions often undergo complex phase transitions with a variety of long-periodic modulations. Among such transition, devil's staircase is the most complex phenomenon, and for it, CeSb is the most famous material, where a number of the distinct phases with long-periodic magnetostructures sequentially appear below the Néel temperature. An evolution of the low-energy electronic structure going through the devil's staircase is of special interest, which has, however, been elusive so far despite 40 years of intense research. Here, we use bulk-sensitive angle-resolved photoemission spectroscopy and reveal the devil's staircase transition of the electronic structures. The magnetic reconstruction dramatically alters the band dispersions at each transition. Moreover, we find that the well-defined band picture largely collapses around the Fermi energy under the long-periodic modulation of the transitional phase, while it recovers at the transition into the lowest-temperature ground state. Our data provide the first direct evidence for a significant reorganization of the electronic structures and spectral functions occurring during the devil's staircase.