Partial Stent-in-Stent Method with an Uncovered Self-Expandable Metallic Stent for Unresectable Malignant Hilar Bile Duct Obstruction.

(1) Background: There is controversy regarding stent placement for unresectable malignant hilar biliary obstruction (UMHBO). We mainly use the partial stent-in-stent (PSIS) method with an uncovered self-expandable metallic stent (UCSEMS) based on the drainage area and patency period. In this study, we investigated the usefulness and safety of the PSIS method. (2) Methods: In total, 59 patients who underwent the PSIS method for UMHBO at our hospital were included in the study. The technical success rate, clinical success rate, time to recurrent biliary obstruction (TRBO) and overall survival (OS) from the first placement, factors affecting TRBO and OS, and early complications within 30 days after the procedure were evaluated retrospectively. (3) Results: The technical and clinical success rates were 100% and 96.6%, respectively, with a TRBO of 121 days [95% confidence interval: 82-231] and an OS of 194 days [95% confidence interval: 113-305] after the first placement. Early complications occurred in nine patients (15.3%), including five cases of cholangitis, three cases of pancreatitis, and one case of cholecystitis. (4) Conclusions: The PSIS method for UMHBO is safe and useful with high technical and clinical success rates.

Anaerobic threshold using sweat lactate sensor under hypoxia.

We aimed to investigate the reliability and validity of sweat lactate threshold (sLT) measurement based on the real-time monitoring of the transition in sweat lactate levels (sLA) under hypoxic exercise. In this cross-sectional study, 20 healthy participants who underwent exercise tests using respiratory gas analysis under hypoxia (fraction of inspired oxygen [FiO2], 15.4 ± 0.8%) in addition to normoxia (FiO2, 20.9%) were included; we simultaneously monitored sLA transition using a wearable lactate sensor. The initial significant elevation in sLA over the baseline was defined as sLT. Under hypoxia, real-time dynamic changes in sLA were successfully visualized, including a rapid, continual rise until volitionary exhaustion and a progressive reduction in the recovery phase. High intra- and inter-evaluator reliability was demonstrated for sLT's repeat determinations (0.782 [0.607-0.898] and 0.933 [0.841-0.973]) as intraclass correlation coefficients [95% confidence interval]. sLT correlated with ventilatory threshold (VT) (r = 0.70, p < 0.01). A strong agreement was found in the Bland-Altman plot (mean difference/mean average time: - 15.5/550.8 s) under hypoxia. Our wearable device enabled continuous and real-time lactate assessment in sweat under hypoxic conditions in healthy participants with high reliability and validity, providing additional information to detect anaerobic thresholds in hypoxic conditions.

Prognostic Implications and Efficacy of Catheter Ablation by Atrial Fibrillation Type.

Background Catheter ablation (CA) for atrial fibrillation (AF) is preferred for paroxysmal AF (PAF) but selectively performed in patients with persistent AF (PersAF). This study aimed to investigate the prognostic differences and consequences of CA based on the AF type. Methods and Results Data from a multicenter AF cohort study were analyzed, categorizing patients as PAF or PersAF according to AF duration (≤7 or >7 days, respectively). A composite of all-cause death, heart failure hospitalization, stroke, and bleeding events during 2-year follow-up and changes in the Atrial Fibrillation Effect on Quality-of-life score were compared. Additionally, propensity score matching was performed to compare clinical outcomes of patients with and without CA in both AF types. Among 2788 patients, 51.6% and 48.4% had PAF and PersAF, respectively. Patients with PersAF had a higher incidence of the composite outcome (12.8% versus 7.2%; P<0.001) and smaller improvements in Atrial Fibrillation Effect on Quality-of-life scores than those with PAF. After adjusting for baseline characteristics, PersAF was an independent predictor of adverse outcomes (adjusted hazard ratio, 1.35 [95% CI, 1.30-1.78], P=0.031) and was associated with poor improvements in Atrial Fibrillation Effect on Quality-of-life scores. Propensity score matching analysis showed that the CA group had significantly fewer adverse events than the medication group among patients with PAF (odds ratio, 0.31 [95% CI, 0.18-0.68]; P=0.002). Patients with PersAF showed a similar but nonsignificant trend. Conclusions PersAF is a risk factor for worse clinical outcomes, including patients' health status. CA is associated with fewer adverse events, although careful consideration is required based on the AF type.

Real-Time Estimation of Anaerobic Threshold during Exercise Using Electrocardiogram in Heart Failure Patients.

Exercise therapy at the aerobic level is highly recommended to improve clinical outcomes in patients with heart failure, in which cardiopulmonary exercise testing (CPX) is required to determine anaerobic thresholds (ATs) but is not available everywhere. This study aimed to validate a method to estimate the AT using heart rate variability (HRV) analysis from electrocardiography data in patients with heart failure. Between 2014 and 2019, 67 patients with symptomatic heart failure underwent CPXs in a single university hospital. During the CPX, RR intervals was measured continuously and the HRV threshold (HRVT), defined as the inflection point of <5 ms2 of a high-frequency component (HFC) using the power spectrum analysis, was determined. Patients were divided into two groups according to the mean HFC at rest (high-HFC group, n = 34 and low-HFC group, n = 33). The high-HFC group showed good correlation between the VO2 at AT and HRVT (r = 0.63, p < 0.001) and strong agreement (mean difference, -0.38 mL/kg, p = 0.571). The low-HFC group also showed modest correlation (r = 0.41, p = 0.017) but poor agreement (mean differences, 3.75 mL/kg, p < 0.001). In conclusion, the HRVT obtained from electrocardiography may be a useful indicator for estimating AT in patients with heart failure.

Delineation of conduction gaps of linear lesions during atrial fibrillation ablation using ultra-high-density mapping.

AIMS: Linear lesions are routinely created by radiofrequency catheter ablation. Unwanted electrical conduction gaps can be produced and are often difficult to ablate. This study aimed to clarify the characteristics of conduction gaps during atrial fibrillation ablation by analysing bidirectional activation maps using a high-density mapping system (RHYTHMIA). METHODS AND RESULTS: This retrospective study included 31 patients who had conduction gaps along pulmonary vein (PV) isolation or box ablation lesions. Activation maps were sequentially created during pacing from the coronary sinus and PV to reveal the earliest activation site, defined by the entrance and exit. The locations, length between the entrance and exit (gap length), and direction were analysed. Thirty-four bidirectional activation maps were drawn: 21 were box isolation lesions (box group), and 13 were PV isolation lesions (PVI group). Among the box group, nine conduction gaps were present in the roof region and 12 in the bottom region, while nine in right PV and four in left PV among the PVI group. Gap lengths in the roof region were longer than those in the bottom region (26.8 ± 11.8 vs. 14.5 ± 9.8 mm; P = 0.022), while those in right PV tended to longer than those in left PV (28.0 ± 15.3 vs. 16.8 ± 8.0 mm, P = 0.201). CONCLUSION: The entrances and exits of electrical conduction gaps were separated, especially in the roof region, indicating that epicardial conduction might contribute to gap formation. Identifying the bidirectional conduction gap might indicate the location and direction of epicardial conduction.

Impacts of an age-related hearing loss allele of cadherin 23 on severity of hearing loss in ICR and NOD/Shi mice.

The age-related hearing loss allele (Cdh23ahl) of the cadherin 23 gene leads to a more severe hearing loss phenotype through additive effects with risk alleles for hearing loss. In this study, we genome edited the Cdh23ahl allele to the wild-type Cdh23+ allele in outbred ICR mice and inbred NOD/Shi mice established from ICR mice and investigated their effects on hearing phenotypes. Several hearing tests confirmed that ICR mice developed early onset high-frequency hearing loss and exhibited individual differences in hearing loss onset times. Severe loss of cochlear hair cells was also detected in the high-frequency areas in ICR mice. These phenotypes were rescued by genome editing the Cdh23ahl allele to Cdh23+, suggesting that abnormal hearing phenotypes develop because of the interaction of the Cdh23ahl and risk alleles in the genetic background of ICR mice. NOD/Shi mice developed more severe hearing loss and hair cell degeneration than ICR mice. Hearing loss was detected at 1 month old. Hair cell loss, including degeneration of cell bodies and stereocilia, was observed in all regions of the cochlea in NOD/Shi mice. Although these phenotypes were partially rescued by genome editing to the Cdh23+ allele, the phenotypes associated with high-frequency hearing were mostly unrecovered in NOD/Shi mice. These results strongly suggest that the genetic background of NOD/Shi mice contain a potential risk allele for the acceleration of early onset high-frequency hearing loss.

Pancreatic Juice Cytology Evaluations Using Synthetic Secretin and Serial Pancreatic Juice Aspiration Cytological Examination for the Diagnosis of Pancreatic Ductal Adenocarcinoma.

Pathological examination by endoscopic ultrasound-fine needle aspiration is not possible in approximately 10% of pancreatic tumor cases. Pancreatic juice cytology (PJC) is considered an alternative diagnostic method. However, its diagnostic capability is insufficient, and PJC has been repeatedly redevised. Serial pancreatic juice aspiration cytological examination (SPACE) and secretin-loaded PJC (S-PJC) have been recently introduced as alternative diagnostic methods. This study aimed to determine the diagnostic capacity and safety of SPACE and S-PJC using a propensity score-matched analysis. The sensitivity, specificity, and accuracy were 75.0%, 100%, and 92.3% for S-PJC, respectively, and 71.4%, 100%, and 92.3% for SPACE, respectively, meaning that there was no significant difference between the groups. Four patients (15.4%) each in the S-PJC and SPACE groups experienced complications, including postendoscopic retrograde cholangiopancreatography, pancreatitis, and cholangitis. Overall, there was no difference in efficacy and safety between the SPACE and S-PJC groups.

Comparison between Target Sample Check Illuminator and White Light Observation in Discriminating the Presence of Target Specimen for Endoscopic Ultrasound-Guided Fine Needle Aspiration Sample.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an essential endoscopic tissue sampling method for diagnosing pancreatobiliary diseases; however, determining the presence of target specimens mixed in the blood by conventional observation is challenging due to the small size of the obtained sample. This study investigated the usefulness of a target sample check illuminator (TSCI) that emits a specific wavelength of light to determine the presence of target specimens. Twenty-seven patients who underwent EUS-FNA at our hospital were included. Conventional white light observation was performed for the collected samples, followed by TSCI; six people evaluated the presence of the target specimen on a 5-point scale. The target specimen discrimination score using TSCI (median: 5) was significantly higher than that using conventional white light observation (median: 1) (p < 0.001). No significant difference was observed in the discrimination score between the evaluator (novice vs. expert, p = 0.162) and puncture needle (22G vs. 25G, p = 0.196). The discriminability of TSCI in the samples obtained using EUS-FNA was significantly higher than that of conventional observation. TSCI does not depend on the evaluator or puncture needle for the identification of the target specimen; hence, it can provide a good pathological specimen and may contribute to the improvement of the diagnostic ability.

Characteristics and health-status outcomes in patients with atrial fibrillation detected via health screening.

BACKGROUND: Early detection of atrial fibrillation (AF) is important. Japan has a universal screening system, and regular health screening (HS) is available to support AF detection without a hospital visit. However, health-related outcomes and other characteristics of HS-detected and conventionally diagnosed AF remain unknown. HYPOTHESIS: That the characteristics and health-related outcomes of patients with HS-detected AF may differ from those of patients whose AF was detected by other procedures. METHODS: In total, 3318 consecutive newly referred AF cases were enrolled; demographic characteristics and health-related and clinical outcomes were compared between two groups created based on the mode of AF detection (the HS and non-HS groups). Health-related outcomes were assessed using the AF Effect on QualiTy-of-life (AFEQT) questionnaire at baseline and after 1 year of follow-up. RESULTS: AF was detected by HS in 25.0% of patients; these patients had lower CHADS2 scores (1.01 vs. 1.50, p < .001), higher prevalence of persistent AF (odds ratio, 95% confidence interval; 2.21, 1.88-2.60) and asymptomatic presentation (3.19, 2.71-3.76), and better baseline QoL scores (83.6 vs. 75.0; p < .001). Catheter ablation was more frequently performed in the HS group at follow-up (44.4% vs. 34.1%; p < .001). At 1-year follow-up, the AFEQT scores of the HS group were significantly better in most subdomains. CONCLUSIONS: In the Japanese registry, AF was detected via HS in 25% of patients referred to specialty centers for management. Notably, the overall health status of patients with HS-detected AF improved after medical interventions, including catheter ablations.

The Usefulness of Peroral Cholangioscopy for Intrahepatic Stones.

Peroral cholangioscopy (POCS) is believed to be effective in treating intrahepatic stones; however, reports on its efficacy are few. We reviewed the results of intrahepatic stones treated with fluoroscopic guidance or POCS. This study included 26 patients who underwent endoscopic treatment for intrahepatic stones at our institution between January 2017 and December 2021. We retrospectively evaluated the procedure time and adverse events in the first session and the rate of complete stone removal. Complete stone removal was achieved in 92% (24/26); POCS was required in 16 of 26 (62%) procedures and the complete stone removal was achieved in 15 of 16 (94%) of these procedures. The POCS group had a significantly longer procedure time than the fluoroscopy group. Cholangitis incidence was high; however, no difference was noted between patients with and without POCS, and all cases were mild and treated conservatively. Endoscopic treatment for intrahepatic stones may lead to an increase in the incidence of cholangitis, requires specialized devices such as a cholangioscope, and should be performed in an established institution by experienced staff. POCS is useful for intrahepatic stones formed upstream of the stenosis and intrahepatic stones piled in the bile duct.

Real-time analysis of heart rate variability during aerobic exercise in patients with cardiovascular disease.

Background: Exercise therapy for cardiovascular disease (CVD) is mainly evaluated based on the heart rate (HR) or Borg scale. However, these indices can be unreliable depending on the patient's medication or their subjective decisions; thus, alternative methods are required for easier and safer implementation of aerobic exercise. Here, we examined whether real-time analysis of HR variability (HRV) can help maintain exercise intensity at the ventilatory threshold (VT) during exercise. Methods: Twenty-eight patients with CVD treated at Keio University Hospital between August 2018 and March 2020 were enrolled. Initially, oxygen uptake (VO2) and HR at the VT were determined using the cardiopulmonary exercise test. Patients then performed aerobic exercise on a stationary bicycle for 30 min while a parameter of HRV, the high-frequency (HF) component, was monitored in real time using an electrocardiograph. The work rate during exercise was adjusted every 2 min to maintain the HF range between 5 and 10. The VO2 and HR values, recorded every 2 min during exercise, were compared with those at VT. The Bland-Altman method was used to confirm similarity. Results: VO2 and HR during exercise were closely correlated with those at VT (e.g., 19 min after exercise initiation; VO2: r = 0.647, HR: r = 0.534). The Bland-Altman plot revealed no bias between the mean values (e.g., 19 min; VO2: -0.22 mL/kg/min; HR: -0.07/min). Conclusion: Real-time HRV analysis with electrocardiograph alone during exercise can provide continuous and non-invasive exercise intensity measurements at VT, promoting safer and effective exercise strategies.

Last Entrainment Sequence: A Novel Diagnostic Technique for Atrial Tachycardia Mimicking Other Supraventricular Tachycardias.

BACKGROUND: Adenosine-sensitive re-entrant atrial tachycardia (AT) originating from near the atrioventricular (AV) node or AV annulus resembles other supraventricular tachycardias (SVTs), and the differential diagnosis is sometimes challenging. OBJECTIVES: This study sought to develop a novel technique to distinguish adenosine-sensitive re-entrant AT from AV nodal re-entrant tachycardia (AVNRT) and orthodromic reciprocating tachycardia (ORT). METHODS: The study retrospectively studied 117 re-entrant SVTs that were successfully entrained by atrial overdrive pacing (AOP) (27 adenosine-sensitive re-entrant ATs, 63 AVNRTs, 27 ORTs). If the second atrial electrogram after AOP (A2) at the earliest atrial activation site (EAAS) accelerated to the pacing cycle length, the EAAS was considered orthodromically activated. Then, we compared the sequence of A2 and the last entrained His bundle (H∗) and QRS complex (V∗). The study hypothesized that the last entrained impulse would activate the EAAS before it enters the AV node, His bundle, and ventricle during AT (A2-H∗-V∗) but would activate the EAAS after the His bundle activation during AVNRT and ORT (H∗-V∗-A2 or H∗-A2-V∗). RESULTS: Orthodromic EAAS activation was documented during AOP in 84 SVTs (72%) when performing AOP from sites proximal to the entrance of SVTs. A2-H∗-V∗ responses were observed in 21 of 25 ATs, but were never for AVNRTs or ORTs. All ORTs and fast-slow AVNRTs had H∗-V∗-A2 responses. Eleven of 21 slow-fast AVNRTs had H∗-A2-V∗ responses. The sensitivity, specificity, and positive and negative predictive values of the A2-H∗-V∗ response for diagnosing AT were 84%, 100%, 100%, and 94%, respectively. CONCLUSIONS: The last entrainment sequence was useful for differentiating ATs with diagnostic difficulties.

Two Loci Contribute to Age-Related Hearing Loss Resistance in the Japanese Wild-Derived Inbred MSM/Ms Mice.

An MSM/Ms strain was established using Japanese wild mice, which exhibit resistance to several phenotypes associated with aging, such as obesity, inflammation, and tumorigenesis, compared to common inbred mouse strains. MSM/Ms strain is resistant to age-related hearing loss, and their auditory abilities are sustained for long durations. The age-related hearing loss 3 (ahl3) locus contributes to age-related hearing in MSM/Ms strain. We generated ahl3 congenic strains by transferring a genomic region on chromosome 17 from MSM/Ms mice into C57BL/6J mice. Although C57BL/6J mice develop age-related hearing loss because of the ahl allele of the cadherin 23 gene, the development of middle- to high-frequency hearing loss was significantly delayed in an ahl3 congenic strain. Moreover, the novel age-related hearing loss 10 (ahl10) locus associated with age-related hearing resistance in MSM/Ms strain was mapped to chromosome 12. Although the resistance effects in ahl10 congenic strain were slightly weaker than those in ahl3 congenic strain, slow progression of age-related hearing loss was confirmed in ahl10 congenic strain despite harboring the ahl allele of cadherin 23. These results suggest that causative genes and polymorphisms of the ahl3 and ahl10 loci are important targets for the prevention and treatment of age-related hearing loss.

Catheter ablation improves outcomes and quality of life in Japanese patients with early-stage atrial fibrillation: A retrospective cohort study.

BACKGROUND: Catheter ablation is widely used as first-line therapy for patients with impaired quality of life; however, whether catheter ablation improves survival and other outcomes in atrial fibrillation (AF) cases remains unclear. OBJECTIVE: The purpose of this study was to evaluate whether catheter ablation reduces adverse clinical outcomes and improves patients' quality of life using data from a contemporary Japanese multicenter registry of patients with early-stage AF. METHODS: The Keio Interhospital Cardiovascular Studies-Atrial Fibrillation registered 3318 patients with AF newly diagnosed at or referred to participating hospitals between 2014 and 2018. Propensity score matching based on 47 demographic variables was performed. We extracted 823 pairs who underwent catheter ablation or medical therapy alone. The primary outcome was the composite of all-cause death, stroke, bleeding events, and heart failure hospitalization during a 2-year follow-up period. Additionally, the Atrial Fibrillation Effect on QualiΤy-of-Life scores at baseline and 1-year follow-up were evaluated. RESULTS: Within the matched cohort, the median time since AF diagnosis was 0.3 years (interquartile range [IQR] 0.1‒2.3 years), age was 67.0 years (IQR 59.0‒73.0 years), and the CHA2DS2-VASc score was 2.0 (IQR 1.0‒2.0). During a median follow-up period of 730 days (IQR 366‒731 days), patients who underwent catheter ablation had a lower risk of primary outcomes (hazard ratio 0.49; 95% confidence interval 0.30‒0.79; P = .004), with a significantly lower risk of heart failure hospitalization (hazard ratio 0.33; 95% confidence interval 0.14-0.77; P = .010) and improved Atrial Fibrillation Effect on QualiΤy-of-Life scores, than did those who received medical therapy. CONCLUSION: In patients with propensity score-matched, early-stage, real-world AF, catheter ablation was associated with a lower risk of adverse clinical events and improved quality of life as compared with medical therapy.

3CL Protease Inhibitors with an Electrophilic Arylketone Moiety as Anti-SARS-CoV-2 Agents.

The novel coronavirus, SARS-CoV-2, has been identified as the causative agent for the current coronavirus disease (COVID-19) pandemic. 3CL protease (3CLpro) plays a pivotal role in the processing of viral polyproteins. We report peptidomimetic compounds with a unique benzothiazolyl ketone as a warhead group, which display potent activity against SARS-CoV-2 3CLpro. The most potent inhibitor YH-53 can strongly block the SARS-CoV-2 replication. X-ray structural analysis revealed that YH-53 establishes multiple hydrogen bond interactions with backbone amino acids and a covalent bond with the active site of 3CLpro. Further results from computational and experimental studies, including an in vitro absorption, distribution, metabolism, and excretion profile, in vivo pharmacokinetics, and metabolic analysis of YH-53 suggest that it has a high potential as a lead candidate to compete with COVID-19.

Myosin VI Haploinsufficiency Reduced Hearing Ability in Mice.

In human, myosin VI (MYO6) haploinsufficiency causes postlingual progressive hearing loss. Because the usefulness of mouse models remains unclear, we produced novel Myo6 null (-/-) mutant mice and analyzed the hearing phenotypes of Myo6+/- (+/-) heterozygous mutants. We first recorded and compared the auditory brainstem responses and distortion product otoacoustic emissions in control Myo6+/+ (+/+) wild-type and +/- mice. These hearing phenotypes of +/- mice were mild; however, we confirmed that +/- mice developed progressive hearing loss. In particular, the hearing loss of female +/- mice progressed faster than that of male +/- mice. The stereocilia bundles of +/- mice exhibited progressive taper loss in cochlear inner hair cells (IHCs) and outer hair cells (OHCs). The loss of OHCs in +/- heterozygotes occurred at an earlier age than in +/+ mice. In particular, the OHCs at the basal area of the cochlea were decreased in +/- mice. IHC ribbon synapses from the area at the base of the cochlea were significantly reduced in +/- mice. Thus, our study indicated that MYO6 haploinsufficiency affected the detection of sounds in mice, and we suggest that +/- mice with Myo6 null alleles are useful animal models for gene therapy and drug treatment in patients with progressive hearing loss due to MYO6 haploinsufficiency.

Change in the local impedance and electrograms recorded by a micro-electrode tip catheter during initial atrial fibrillation ablation.

BACKGROUND: A novel measurement of the local impedance (LI) and electrograms recorded from micro-electrodes on catheter tip has been developed. However, the data during pulmonary vein (PV) ablation is not sufficient. We aimed to investigate the utility of this measurement during initial atrial fibrillation (AF) ablation. METHODS: We investigated 111 representative radiofrequency applications in 7 AF patients without a history of prior ablation (6 males, age 68 [65-72] years, 2 persistent AF). The ablation strategy was PV isolation for paroxysmal AF and single ring box isolation for persistent AF, using MiFi catheter. The correlation of the generator impedance (GI) drop and LI drop after radiofrequency applications and the predictive value of the initial LI elevation before radiofrequency applications for LI drop were analyzed. Also, the LI and GI drop were investigated according to the location of RF applications. RESULTS: The LI drop was higher than GI drop (23.7 [16.4-35.7] and 9.0 [6.0-12.0]; P < .01). There were correlations between the initial LI elevation and LI drop (R 2 = 0.466, P < .01) and between the LI and GI drop (R 2 = 0.263, P < .01). The LI drops significantly differed according to the different anatomical localizations by the Kruskal-Wallis test, although the GI drops did not differ (P < .01 and P = .49, respectively). CONCLUSION: LI drop was associated with initial LI elevation and was larger than GI drop. LI drop was different according to locations, although GI drop was not. These findings might indicate that LI drop would be a more sensitive marker for lesion formation than GI drop.

A novel device for detecting anaerobic threshold using sweat lactate during exercise.

The lactate threshold (LT1), which is defined as the first rise in lactate concentration during incremental exercise, has not been non-invasively and conveniently determined in a clinical setting. We aimed to visualize changes in lactate concentration in sweat during exercise using our wearable lactate sensor and investigate the relationship between the lactate threshold (LT1) and ventilatory threshold (VT1). Twenty-three healthy subjects and 42 patients with cardiovascular diseases (CVDs) were enrolled. During exercise, the dynamic changes in lactate values in sweat were visualized in real-time with a sharp continuous increase up to volitional exhaustion and a gradual decrease during the recovery period. The LT1 in sweat was well correlated with the LT1 in blood and the VT1 (r = 0.92 and 0.71, respectively). In addition, the Bland-Altman plot described no bias between the mean values (mean differences: - 4.5 and 2.5 W, respectively). Continuous monitoring of lactate concentrations during exercise can provide additional information for detecting the VT1.

c.753A>G genome editing of a Cdh23ahl allele delays age-related hearing loss and degeneration of cochlear hair cells in C57BL/6J mice.

C57BL/6J mice have long been studied as a model of age-related hearing loss (ARHL). In C57BL/6J mice, ARHL begins in the high-frequency range at 3 months of age and spreads toward low frequencies by 10 months of age. We previously confirmed that c.753A>G genome editing of an ahl allele (c.753A) in the cadherin 23 gene (Cdh23) suppressed the onset of ARHL until 12 months of age. We further investigated the hearing phenotypes of the original and genome-edited C57BL/6J-Cdh23+/+ (c.753G/G) mice until 24 months of age. The hearing tests revealed that most of the C57BL/6J mice maintained good hearing levels until 14 months of age following genome editing of a Cdh23ahl allele. However, the hearing levels of the C57BL/6J-Cdh23+/+ mice gradually declined, and severe ARHL developed with increasing age. ARHL in the C57BL/6J mice was correlated with degeneration of the stereocilia in cochlear hair cells. The stereocilia degeneration was rescued in the C57BL/6J-Cdh23+/+ mice at 12 months of age, but the stereocilia bundles exhibited abnormal phenotypes similar to those of the original C57BL/6J mice at more advanced ages. Therefore, genome editing of Cdh23ahl did not completely suppress ARHL in C57BL/6J mice. We also compared the hearing levels of C57BL/6J-Cdh23+/+ mice with those of C3H/HeN and MSM/Ms mice, which carry the Cdh23+ allele. The severity and onset patterns of ARHL in the C57BL/6J-Cdh23+/+ mice differed from those observed in other Cdh23+/+ mice. Therefore, we hypothesize that other susceptible and/or resistant alleles of ARHL exist in the genetic backgrounds of these mice.

Left Ventricular Diastolic Dysfunction Is Associated With the Prevalence of Paroxysmal Atrial Fibrillation Determined on the Latest Echocardiographic Criteria.

Background: The relationship between left ventricular diastolic dysfunction (LVDD) and paroxysmal atrial fibrillation (PAF) remains unclear because of a lack of standard measures to evaluate LVDD. Accordingly, we examined the association between the prevalence of PAF and each LVDD grade determined according to the latest American Society of Echocardiography guidelines. Methods and Results: In all, 2,063 patients without persistent AF who underwent echocardiography at Saitama Municipal Hospital from July 2016 to June 2017 were included in the study. Patients were divided into LVDD 6 categories: No-LVDD (n=1,107), Borderline (n=392), Grade 1 (n=204), Indeterminate (n=62), Grade 2 (n=254), and Grade 3 (n=44). PAF was documented in 111 (10.0%), 81 (20.7%), 28 (13.7%), 6 (9.7%), 52 (20.5%), and 24 (54.5%) patients in the No-LVDD, Borderline, Grade 1, Indeterminate, Grade 2, and Grade 3 categories, respectively. PAF prevalence was higher in patients with Grade 3 LVDD across the whole study population. Subgroup analyses showed that the prevalence of PAF increased with increased LVDD grade in patients with reduced left ventricular ejection fraction. This relationship was significant in multivariate analysis including various patient characteristics. Conclusions: LVDD severity determined on the basis of the latest echocardiographic criteria was associated with the prevalence of PAF. The present findings shed light on the development of new therapeutic markers for PAF.