Long-term prognostic significance of dispersion of ventricular repolarization in patients with cardiac sarcoidosis

Background

Although the presence of cardiac involvement is recognised as a determinant of worse clinical outcomes in sarcoidosis patients, the determinants of adverse outcomes in patients with cardiac sarcoidosis (CS) have not been well understood. T-peak to T-end interval (TpTe) on the surface electrocardiogram (ECG) was proposed as a marker of dispersion of ventricular repolarisation. Prolonged TpTe to QT interval ratio (TpTe/QT) represents a period of potential vulnerability to reentrant ventricular arrhythmias. Notably, prolonged TpTe/QT has been associated with increased risk of mortality in hypertrophic cardiomyopathy, congenital long-QT syndrome, and Brugada syndrome. However, its prognostic implication in patients with CS is unclear.

Purpose

We sought to investigate whether TpTe/QT was associated with long-term clinical outcomes in patients with CS.

Methods

A total of 108 consecutive CS patients between August 1986 and March 2019 in two academic hospitals who had ECG data before initiation of immunosuppressive therapy were examined. We excluded patients who received pacemaker (n=15) or cardiac resynchronization therapy (n=3) at the time of ECG. Ultimately, 90 CS patients were included in this study. All standard 12-lead ECGs were recorded at 25 mm/s with an amplification of 10 mm/mV. TpTe was measured from the peak of T wave to the end of T wave which defined as the intersection of the tangent to the down slope of the T wave and the isoelectric line. Lead V5 was selected for the analyses. If V5 is not suitable for analyses, V4 was selected. The primary outcome was the composite of advanced atrioventricular block (AVB), ventricular tachycardia or ventricular fibrillation (VT/VF), heart failure hospitalisation and all-cause death.

Results

During a median follow-up period of 4.70 (interquartile range [IQR] 2.06–7.23) years, adverse events occurred in 21 patients (23.3%), including 2 advanced AVB, 12 VT/VF, 4 heart failure hospitalisation and 3 all-cause death. Events group had higher TpTe/QT compared to no events group (0.231 [IQR 0.193–0.261] vs. 0.282 [IQR 0.263–0.304] P<0.001). Kaplan-Meier analyses revealed that the primary outcome, especially VT/VF or sudden cardiac death more frequently occurred in patients with higher TpTe/QT (≥0.242, the median) compared to those with lower TpTe/QT (Figure 1). Multivariable Cox regression analysis showed that higher TpTe/QT was independently associated with increased subsequent risk of adverse events (hazard ratio 1.09, 95% confidence interval [CI] 1.02–1.17, P=0.014) even after adjustment for age, sex and left ventricular ejection fraction. Furthermore, the optimal cut-off value of TpTe/QT for the discriminatory of primary outcome was 0.257, and c-index was 0.77 (95% CI 0.64–0.89).

Conclusions

Higher TpTe/QT was associated with worse long-term clinical outcomes in patients with CS. Our findings indicate the importance of assessing TpTe/QT for risk stratification in patients with CS.

Figure 1

Funding Acknowledgement

Type of funding source: None

Prognostic impact of right ventricular overload in patients with acute coronary syndrome

Background

Right ventricular (RV) overload is associated with adverse outcome in patients with chronic heart failure. However, its prognostic value in acute coronary syndrome (ACS) patients remains unknown.

Purpose

The purpose of this study was to investigate the prevalence and prognostic impact of right ventricular overload in ACS patients.

Methods

We studied 2797 ACS patients from Mie ACS registry, a prospective and multicenter registry in Japan. They were divided into 4 subgroups according to the severity of RV overload and the extent of Left Ventricle Ejection Fraction (LVEF) assessed by echocardiography before hospital discharge. High RV overload was defined as trans-tricuspid pressure gradient (TRPG) ≥40mmHg and preserved LVEF was defined as ≥50%. The primary outcome was defined as 2-year all-cause mortality. Median follow up duration was 730 days (1–2215 days).

Results

High RV overload was detected in 76 patients (2.7%). In basic patients characteristics, high RV overload patients were significantly older and higher killip classification than low RV overload patients (P<0.01, respectively). Laboratory data in high RV overload patients showed lower hemoglobin level and higher serum creatinine level than those in low RV overload patients (P<0.01, respectively).

Echocardiographic findings in high RV overload represented lower LVEF, higher rate of moderate or severe mitral regurgitation and left atrial enlargement than those in low RV overload patients (P<0.01, respectively).

During the follow-up periods (median 730 days), 260 (9.3%) patients experienced all-cause death. Multivariate cox hazard regression analysis for all-cause mortality demonstrated that high RV overload was an independent poor prognostic factor in the entire study population. Among patients with preserved LVEF, high RV overload resulted in an increased risk of all-cause mortality compared to low RV overload (P<0.0001).

Conclusion

In ACS patients, high RV overload strongly contributes to worsening of prognosis regardless of the extent of LVEF.

Kaplan-Meier survival curve

Funding Acknowledgement

Type of funding source: None

Impact of hinge motion on stent edge restenosis after new generation drug-eluting-stent implantation in RCA

Background

Edge restenosis still occurs after stent implantation, even by using new generation drug-eluting stents (DES) considered to have favorable biomechanical properties. Mechanical stress imposed on the stent edge are thought to be aggravated by hinge motion at a point between the stented and unstented segments, inducing chronic local inflammation and neointimal overgrowth.

Purpose

The aim of this study was to investigate the association between the development of edge restenosis and hinge motion in right coronary artery (RCA) where the excessive vessel movement is commonly observed.

Methods

Among consecutive 650 lesions in RCA where new generation DESs were implanted between 2009 and 2019, 427 serial lesions with sets of angiographies at baseline and follow-up (6–18 month) were included. In addition to conventional quantitative angiography analysis, hinge angle at stent edges was measured (Fig. 1). All the appropriate data for intravascular imaging were analyzed for both stent edges and reference segments.

Results

Binary restenosis occurred in 43 lesions, and 39 of them were referred to re-intervention. Fifty five percent of them were related to stent edges (15 at proximal and 9 at distal edges). Classical risk factors including diabetes and hemodialysis were more prevalent in the restenosis group (p<0.05). Hinge angle was statistically larger in edge restenosis group than body restenosis or no restenosis group (17.3° vs 11.6° vs 10.6°, p<0.001, Fig. 2). In per-edge analysis, hinge angle, dissection and residual plaque ratio were the independent predictors for binary restenosis (Table 1) with the optimal cut-off value of hinge angle 11.5°. The coexistence of excessive hinge angle and residual plaque burden had an amplified effect on the angiographic stenotic progression at stent edge (p for interaction <0.001) and the incidents of binary restenosis (16.7% vs 1.7% p<0.01, Figs. 3,4).

Conclusion

Substantial stress determined by angulation at the stent edge and its interaction with residual plaque can be considered as one of the plausible mechanisms for edge restenosis. For tortuous RCA lesions, it would be important to decide the stent-landing zone for minimizing hinge motion and optimize the future stent design.

Funding Acknowledgement

Type of funding source: None

Effects of laundry-hanging motion on oxygen uptake and ventilation in healthy young women

Many patients with chronic obstructive pulmonary disease (COPD) experience problems during performance of activities of daily living. These problems may lead to reduced physical activity. The purpose of this study was to reveal the influence on the oxygen uptakes in motion methods of hanging on laundry. Eighteen healthy females were recruited for participation in this study. They performed three kinds of movement to hang on laundry. Participants performed the following three actions: (1) hanging some towels on bars with a low stand in a sitting position (Action 1), (2) hanging some towels on bars with a low stand in a standing position (Action 2) and (3) hanging some towels on bars with a high stand in a standing position (Action 3). We measured metabolic and ventilatory requirements during these actions by use of an expires gas analyser. Mutual comparison of the three different types action showed significant differences in the oxygen uptake (VO2), carbon dioxide output (VCO2), minute ventilation (VE), and metabolic equivalents (METs). On the other hands, the differences in respiratory rate (RR) among these three actions were not significant. Action 3 tended to have the most increased values in VO2, VCO2, VE and METs. The Action 1 tended to behave the lowest value. The oxygen uptake and ventilation variables may be influenced by the methods used in hanging laundry.

Urinary biomarkers of kidney tubule injury, risk of acute kidney injury, and mortality in patients with acute ischaemic stroke treated at a stroke care unit

BACKGROUND AND PURPOSE

Urinary liver-type fatty-acid binding protein (L-FABP), which is a biomarker of kidney tubule injury, has been studied extensively and established as a risk marker of acute kidney injury (AKI). The aim of this study was to investigate whether kidney tubule injury is associated with the development of AKI and mortality in patients with acute ischaemic stroke.

METHODS

Acute ischaemic stroke patients hospitalized in the stroke care unit (SCU) within 24 h after symptom onset were prospectively investigated. AKI was defined on the basis of Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Baseline urinary L-FABP was measured on admission. We evaluated the associations among urinary L-FABP, incidence of AKI, and 90-day mortality adjusted for renal function, albuminuria and other potentially predictive variables, using multivariable analysis.

RESULTS

In total, 527 acute ischaemic stroke patients (342 men, median age 74 years) were enrolled in the study. Twenty-seven patients (5.1%) experienced AKI within 7 days of admission. In the univariate analysis, high urinary L-FABP level had positive associations with AKI [53.8 μg/g creatinine (Cr) vs. 3.9 μg/g Cr; P < 0.001] and 90-day mortality (15.5 μg/g Cr vs. 4.0 μg/g Cr; P < 0.001). In the multivariate analysis, elevated urinary L-FABP level (per 10-μg/g Cr increase) was independently associated with AKI (odds ratio 1.225, 95% confidence interval (CI) 1.083-1.454; P = 0.003) and 90-day mortality (hazard ratio 1.091, 95% CI 1.045-1.138; P < 0.001).

CONCLUSION

Urinary biomarkers of kidney tubule injury are independently associated with the development of AKI and 90-day mortality in patients with acute ischaemic stroke treated at the SCU.

SAT0146 INHIBITION OF RADIOGRAPHIC PROGRESSION BY IGURATINOD IN 116 JAPANESE RHEUMATOID ARTHIRITIS PATIENTS DESPITE CONVENTIONAL SYNTHETIC DISEASE-MODIFYING ANTIRHEUMATIC DRUGS THERAPY

Background:

Japanese double-blind clinical practice studies of Iguratimod (IGU) for active rheumatoid arthritis (RA) patients indicated an early and sustained efficacy as a new conventional synthetic disease-modyfing anti-rheumatic drugs (csDMARDs) [1] as well as the safety of the treatment[2]. IGU also inhibit activation of NFkB and production of RANKL, indicating strong inhibiting activity against bone destruction. However, studies focused on the inhibitory effects of joint destruction by IGU has been poorly documented in clinical practice (3).

Objectives:

To evaluate inhibitory effect during 1 year by additional IGU therapy in 116 RA patients despite csDMARDs therapy.

Methods:

Inhibitory effects of joint damage were evaluated by modified total Sharp scoring (mTSS) at baseline and 1 year after IGU prescription. RA activity was measured by DAS28-ESR.

Results:

The subjects were 116 cases, 30 male, age 63.2 yrs, disease duration 93.7 months. MTX was used weekly (84 cases, 72.4%), and cs DMARDs were used as BUC 43 cases, SASP 13 cases, TAC 5 cases, and LEF 1 cases. bDMARDs were used even in 8 cases, and steroids were used in 3.9 mg (70 cases, 60.3 %). Complications were observed in 70 cases (60.3%). DAS28-ESR were significantly improved from 4.29 (baseline) to 3.65 (6 months), 3.68 (12 months), respectively (P<0.0001). As shown in Figure 1, joint destruction measured by mTSS was significantly suppressed from 7.74 to 0.57 at 1 year (P<0.0001). 70.6% of patients satisfied structural remission (ΔmTSS≤0.5). Clinically relevant radiographic progression (CRRP)(mTSS>3) was observed in 10 cases (8.6%), and rapid radiographic progression(RRP) (mTSS≥5) was observed in 2 cases (1.6%). Adverse events were observed in 26 cases (22.4 %).

To investigate prognostic factor for CRRP, clinical data in baseline, 6, 12 months between ten patients with CRRP and 82 patients with structural remission were compared. As shown in Table 1, longer disease duration, more SJC (P<0.05), High CRP level(P<0.005) were prognostic for CRRP in IGU treated patients.

Conclusion:

Iguratimod suppressed not only clinical activities but also joint destruction in RA patients resistant to csDMARDs therapy.

Table 1. Prognostic factor for CRRP

References:

[1]Ishiguro N, Yamamoto K, Katayama K et al. Concomitant iguratimod therapy in patients with active rheumatoid arthritis despite stable doses of methotrexate a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2013;23(3):430-9

[2]Hara M, Ishiguro N, Katayama K et al. Safety and efficacy of combination therapy of iguratimod with methotrexate for patients with active rheumatoid arthritis with an inadequate response to methotrexate: an open-level extension of a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2014;24(3):410–8.

[3]Ishikawa K, Ishikawa J.Iguratimod, a synthetic disease modifying anti-rheumatic drug inhibiting the activation of NF-jB and production of RANKL: Its efficacy, radiographic changes,safety and predictors over two years’ treatment for Japanese rheumatoid arthritis patients. Mod.Rheumatol.2019,29(3), 418–429.

Disclosure of Interests:

None declared

FRI0127 Suppression of radiographic progression after gradual methotrexate tapering in patients with rheumatoid arthritis patients maintaining low disease activity - Prospective multicenter study-

Background:

Many studies have been reported to reduce/discontinue Biologics in the treatment of rheumatoid arthritis (RA). In contrast, study for tapering methotrexate (MTX) has been limited (1,2).

Objectives:

We prospectively examined whether bone destruction will progress at 48 weeks after tapering or discontinuing MTX (UMIN000028875).

Methods:

The subjects were RA patients who have maintained low disease activity or lower for 24 weeks or more in DAS28-CRP after MTX administration. Patients having PDUS Grade 2 or 3 per site by bilateral hand ultrasonography (26 area) were excluded in this study owing to risk for joint destruction. The joint destruction was evaluated by the joint X-ray evaluation by modified total Sharp scoring (mTSS) at 1 year after the start of tapering MTX. Evaluation of clinical disease activities, severe adverse events, the continuation rate during MTX tapering were also evaluated. According to tapering response, prognostic factor for good response for tapering, joint destruction was determined. Predictors for successful tapering MTX and progression of bone destruction were determined. Statistical analysis was performed by t-test or Wilcoxon rank sum test using SAS .13.2 software.

Results:

The subjects were 79 (16 males, 63 females). Age average 60.9 years, disease duration 4 years 4 months, MTX dose 8.43 mg / w, DAS28-CRP 1.52, DMARDs (24.3%), ACPA 192.7 U / ml (70.5%), RF 55.6 IU / ml (65.4%).MTX was tapered from an average of 8.43 mg / w before study to 5.46 mg / w one year later. In the treatment evaluation, DAS28-CRP increased from 1.52 to 1.84. 89.7% of subjects did not progress joint damage. Other disease activities significantly increased (Table 1). The one-year continuation rate was 78.2%. Since tapering effects were varied widely, we divided patients into three groups; Flared group (N=14, initial MTX dose 8.71mg/w, final MTX dose 8.42mg/w), Low response group (N=31, final MTX reduction rate< 50%, initial MTX dose 8.93mg/w, final MTX dose 6.22mg/w), High response group (N=34, final MTX reduction rate≥ 50%, initial MTX dose 8.5mg/w, final MTX dose 3.15mg/w)(Table 2).Higher RF value at baseline and higher MTX dose at 3M, 6M were predictors of whether a subject was in Low response group or High Response group. Higher RF value and mTSS at baseline and higher MTX dose at 6M were predictors whether a subject was in Flared group or High response group. Lower age was predictor of whether a subject was in Flared group or Low responder group. Finally, mean ΔmTSS /y in Flared group (0.36) was not significantly higher than in low response group (0.07) and in high response group (0.01).

Table 1Table 2.

Predictors for successful tapering MTX and progression of bone destruction

Conclusion:

Patients with MTX-administered low disease activity and finger joint echo PDUS grade 1 satisfy almost no joint destruction even after MTX reduction. For tapering, predictors may be helpful for maintaining patient’s satisfaction.

References:

[1]Baker KF, Skelton AJ, Lendrem DW et al. Predicting drug-free remission in rheumatoid arthritis: A prospective interventional cohort study. J. Autoimmunity. 2019;105: 102298.

[2]Lillegraven S, Sundlisater N, Aga A et al. Tapering of Conventional Synthetic Disease Modifying Anti-Rheumatic Drugs in Rheumatoid Arthritis Patients in Sustained Remission: Results from a Randomized Controlled Trial. American College of Rheumatology. 2019; Abstract L08.

Disclosure of Interests:

None declared

AB0298 LONG-TERM SUPPRESSION OF RAPID RADIOGRAPHIC PROGRESSION AFTER DISCONTINUATION/REDUCTION OF SHORT-TERM BIOLOGIC THERAPY IN PATIENTS WITH EARLY DESTRUCTIVE RHEUMATOID ARTHRITIS ACCOMPANIED WITH EXTENSIVE BONE MARROW EDEMA

Background:

We reported that short-term (3 or 6 months) treatment with biologics (BIO) group compared with conventional synthetic non-biological disease-modifying anti rheumatic drug (csDMARDs) enhanced group is more effective in the reducing bone marrow edema (BE) and improving structural remission in early destructive RA accompanied with extensive hand BM despite csDMARDs therapy (1).

Objectives:

Purpose of this extended study is to investigate whether suppression of RRP will maintain after the discontinuation/reduction of short term biological treatment during over 1 year. Clinical registration number; (UMIN-CTR 000013614)(Figure 1)

Methods:

RA disease activity was evaluated by DAS28-ESR after BIO withdrawal/reduction at 12 months. Bone destruction was determined by modified total Sharp scoring (mTSS) using by conventional radiography expressed as yearly progression of mTSS (ΔmTSS/y) at 12 months. Statistical analysis were performed by t-test or Wilcoxon rank sum test using SAS .13.2 software

Results:

Fourteen out of 23 patients in BIO group achieved improvement of BM (>70% improvement of baseline BE). Three patient continued BIO. Among 11 patient started to discontinuation/reduction of BIO, 7 patients were successful for discontinuation of BIO. Four patients flared (Table 1). Mean DAS28-ESR, mean ΔmTSS/y at 0, 12 months after discontinuation in 7 patients were 1.77, 2.02 and -0.66,-0.44, respectively (no significant difference between values in 0 and12 month). In contrast, those in 4 flared patients were 1.91, 4.08 and 0, 1.83, respectively (significant difference). Finally, to resolve baseline prognostic factors for improvement of BE for biological treatment, we compared baseline data between 14 BE improved and 9 BE unimproved RA patients. Low DAS28-ESR at 3 or 6 month (P<0.001) are indicated for significant prognostic factor for improvement of BE, although Low DAS28-ESR at baseline (P=0.07) may associate improvement of BE.

Table 1.

Summary of 1 year clinical data in 11 patients treated in BIO discontinuation/reduction after improvement of BE by short-term treatment of BIO

Conclusion:

Results of this study indicated suppression of RRP will maintain during over 1 year after the discontinuation of short term biological treatment in some patients. We recommend that a short-term treatment with biologics for early RA patients, who are resistant to non-bio DMARDs therapy and at high risk to transit to RRP, will be an effective and economical treatment strategy.

References:

[1]K. Katayama, T. Okubo, S. Sato et al. Prevention of extensive bone marrow edema and consequent rapid radiographic progression by short term usage of biologics in DMARDs resistant patients with early destructive rheumatoid arthritis. EULAR meeting. FRI 0124(2018).

Disclosure of Interests:

None declared

g Factor of the ^{99}Zr (7/2^{+}) Isomer: Monopole Evolution in the Shape-Coexisting Region

The gyromagnetic factor of the low-lying E=251.96(9)  keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5)  ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |μ|=2.31(14)μ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

Regional pancreatoduodenectomy versus standard pancreatoduodenectomy with portal vein resection for pancreatic ductal adenocarcinoma with portal vein invasion

Background

Pancreatoduodenectomy (PD) with portal vein resection (PVR) is a standard operation for pancreatic ductal adenocarcinoma (PDAC) with portal vein (PV) invasion, but positive margin rates remain high. It was hypothesized that regional pancreatoduodenectomy (RPD), in which soft tissue around the PV is resected en bloc, could enhance oncological clearance and survival.

Methods

This retrospective study included consecutive patients who underwent PD with PVR between January 2005 and December 2016 in a single high‐volume centre. In standard PD (SPD) with PVR, the PV was skeletonized and the surrounding soft tissue dissected. In RPD, the retropancreatic segment of the PV was resected en bloc with its surrounding soft tissue. The extent of lymphadenectomy was similar between the procedures.

Results

A total of 268 patients were included (177 SPD, 91 RPD). Tumours were more often resectable in patients undergoing SPD (60·5 per cent versus 38 per cent in those having RPD; P = 0·014), and consequently they received neoadjuvant therapy less often (7·9 versus 25 per cent respectively; P < 0·001). R0 resection was achieved in 73 patients (80 per cent) in the RPD group, compared with 117 (66·1 per cent) of those in the SPD group (P = 0·016), although perioperative outcomes were comparable between the groups. Median recurrence‐free (RFS) and overall (OS) survival were 17 and 32 months respectively in patients who had RPD, compared with 11 and 21 months in those who had SPD (RFS: P = 0·003; OS: P = 0·004).

Conclusion

RPD is as safe and feasible as SPD, and may increase the survival of patients with PDAC with PV invasion.

Intensive uric acid-lowering therapy in CKD patients: the protocol for a randomized controlled trial

BACKGROUND

Hyperuricemia would be a risk factor for the development/progression of CKD. However, several studies showed U-shape association between serum uric acid level and renal impairment, suggesting that hypouricemia was rather associated with renal dysfunction. Perhaps, there is the optimal target level of serum UA for renal function.

METHODS

The Target-UA study is a multicenter randomized controlled trial. Eligible CKD patients (eGFR ≥ 30, < 60 mL/min/1.73 m2 and urine protein < 0.5 g/gCr or urine albumin to creatinine ratio (ACR) < 300 mg/gCr) with serum UA ≥ 8.0 mg/dL (≥ 7.0 mg/dl: under the treatment) will be enrolled and be randomly assigned to the intensive therapy group (target serum UA level ≥ 4.0 mg/dL, < 5.0 mg/dL) or the standard therapy group (serum UA level ≥ 6.0 mg/dL, < 7.0 mg/dL). Topiroxostat, a new xanthine oxidase inhibitor, will be administered to treat hyperuricemia. The primary endpoint is a change in logarithmic value of urine ACR between baseline and week 52 of treatment. The secondary endpoints include changes in serum UA, eGFR, urine protein, lipid profile, and onset of composite cardiovascular events, renal events, gouty arthritis, and attack of urolithiasis. The number of subjects has been set to be 185 in each group for a total of 370.

DISCUSSION

This is the first study, to the best of our knowledge, to determine the optimal target level of serum UA for renal protection and is expected to lead to progress in CKD treatment.

TRIAL REGISTRATION

(UMIN000026741 and jRCTs051180146).

A Targeted Genetic Association Study of the Rare Type of Osteomyelitis

Chronic nonbacterial osteomyelitis is a rare bone disorder that can be found in the jaw. It is often associated with systemic conditions, including autoimmune deficiencies. However, little is known about how the genetic and immunologic background of patients influences the disease. Here, we focus on human leukocyte antigen (HLA), killer cell immunoglobulin-like receptors (KIRs), and their specific combinations that have been difficult to analyze owing to their high diversity. We employed a recently developed technology of simultaneous typing of HLA alleles and KIR haplotype and investigated alleles of the 35 HLA loci and KIR haplotypes composed of centromeric and telomeric motifs in 18 cases and 18 controls for discovery and 472 independent controls for validation. We identified an amino acid substitution of threonine at position 94 of HLA-C in combination with the telomeric KIR genotype of haplotype tA01/tB01 that had significantly higher frequency (>20%) in the case population than in both control populations. Multiple logistic regression analysis based on a dominant model with adjustments for age and sex revealed and validated its statistical significance and high predictive accuracy (C-statistic ≥0.85). Structure-based analysis revealed that the combination of the amino acid change in HLA-C and the telomeric genotype tA01/tB01 could be associated with lower stability of HLA-C. This is the first case-control study of a rare disease that employed the latest sequencing technology enabling simultaneous typing and investigated amino acid polymorphisms at HLA loci in combination with KIR haplotype.

Identification of malignant early repolarization pattern by late QRS activity in high-resolution magnetocardiography

Background

The early repolarization pattern (ERP) in electrocardiography (ECG) has been considered as a risk for ventricular fibrillation (VF), but effective methods for identification of malignant ERP are still required. We investigated whether high spatiotemporal resolution 64‐channel magnetocardiography (MCG) would enable distinction between benign and malignant ERPs.

Methods

Among all 2,636 subjects who received MCG in our facility, we identified 116 subjects (43 ± 18 years old, 54% male) with inferior and/or lateral ERP in ECG and without structural heart disease, including 13 survivors of VF (ERP‐VF(+)) and 103 with no history of VF (ERP‐VF(−)). We measured the following MCG parameters in a time‐domain waveform of relative current magnitude: (a) QRS duration (MCG‐QRSD), (b) root‐mean‐square of the last 40 ms (MCG‐RMS40), and (c) low amplitude (<10% of maximal) signal duration (MCG‐LAS).

Results

Compared to ERP‐VF(−), ERP‐VF(+) subjects presented a significantly longer MCG‐QRS (108 ± 24 vs. 91 ± 23 ms, p = .02) and lower MCG‐RMS40 (0.10 ± 0.08 vs. 0.25 ± 0.20, p = .01) but no difference in MCG‐LAS (38 ± 22 vs. 29 ± 23 ms, p = .17). MCG‐QRSD and MCG‐RMS40 showed significantly larger area under the ROC curve compared to J‐peak amplitude in ECG (0.72 and 0.71 vs. 0.50; p = .04 and 0.03). The sensitivity, specificity, and odds ratio for identifying VF(+) based on MCG‐QRSD ≥ 100 ms and MCG‐RMS40 ≤ 0.24 were 69%, 74%, and 6.33 (95% CI, 1.80–22.3), and 92%, 48%, and 10.9 (95% CI, 1.37–86.8), respectively.

Conclusion

Magnetocardiography is an effective tool to distinguish malignant and benign ERPs.

Liquid Chromatographic Determination of Glyphosate in Water-Soluble Granular Formulations: Collaborative Study

A liquid chromatographic (LC) method for the determination of glyphosate in various water-soluble granular formulations was tested by 28 laboratories. Samples were dissolved in mobile phase and injected directly into an LC system with a 25 cm SAX column and a mobile phase of 96% aqueous buffer solution, 0.0062M KH2PO4, and 4% methanol. Detection was by UV absorption at 195 nm. Manual or automated injections were made via fixed-volume loops. Calculations were based on peak area comparisons with external standards. The collaborative study analyzed 5 matched pairs of 4 water-soluble granular formulations, with one determination per sample. The study generated 138 matched pairs, which were analyzed by using the AOAC spreadsheet and Youden’s matched-pair calculations. Coefficients of variation for the 4 formulations ranged from 0.65 to 1.37%. The LC method for the determination of glyphosate in water-soluble granular formulations has been adopted first action by AOAC INTERNATIONAL.