Accuracy of 11 Wearable, Nearable, and Airable Consumer Sleep Trackers: Prospective Multicenter Validation Study

BACKGROUND

Consumer sleep trackers (CSTs) have gained significant popularity because they enable individuals to conveniently monitor and analyze their sleep. However, limited studies have comprehensively validated the performance of widely used CSTs. Our study therefore investigated popular CSTs based on various biosignals and algorithms by assessing the agreement with polysomnography.

OBJECTIVE

This study aimed to validate the accuracy of various types of CSTs through a comparison with in-lab polysomnography. Additionally, by including widely used CSTs and conducting a multicenter study with a large sample size, this study seeks to provide comprehensive insights into the performance and applicability of these CSTs for sleep monitoring in a hospital environment.

METHODS

The study analyzed 11 commercially available CSTs, including 5 wearables (Google Pixel Watch, Galaxy Watch 5, Fitbit Sense 2, Apple Watch 8, and Oura Ring 3), 3 nearables (Withings Sleep Tracking Mat, Google Nest Hub 2, and Amazon Halo Rise), and 3 airables (SleepRoutine, SleepScore, and Pillow). The 11 CSTs were divided into 2 groups, ensuring maximum inclusion while avoiding interference between the CSTs within each group. Each group (comprising 8 CSTs) was also compared via polysomnography.

RESULTS

The study enrolled 75 participants from a tertiary hospital and a primary sleep-specialized clinic in Korea. Across the 2 centers, we collected a total of 3890 hours of sleep sessions based on 11 CSTs, along with 543 hours of polysomnography recordings. Each CST sleep recording covered an average of 353 hours. We analyzed a total of 349,114 epochs from the 11 CSTs compared with polysomnography, where epoch-by-epoch agreement in sleep stage classification showed substantial performance variation. More specifically, the highest macro F1 score was 0.69, while the lowest macro F1 score was 0.26. Various sleep trackers exhibited diverse performances across sleep stages, with SleepRoutine excelling in the wake and rapid eye movement stages, and wearables like Google Pixel Watch and Fitbit Sense 2 showing superiority in the deep stage. There was a distinct trend in sleep measure estimation according to the type of device. Wearables showed high proportional bias in sleep efficiency, while nearables exhibited high proportional bias in sleep latency. Subgroup analyses of sleep trackers revealed variations in macro F1 scores based on factors, such as BMI, sleep efficiency, and apnea-hypopnea index, while the differences between male and female subgroups were minimal.

CONCLUSIONS

Our study showed that among the 11 CSTs examined, specific CSTs showed substantial agreement with polysomnography, indicating their potential application in sleep monitoring, while other CSTs were partially consistent with polysomnography. This study offers insights into the strengths of CSTs within the 3 different classes for individuals interested in wellness who wish to understand and proactively manage their own sleep.

Characterization of attentional event-related potential from REM sleep behavior disorder patients based on explainable machine learning

BACKGROUND AND OBJECTIVE

Idiopathic rapid eye movement sleep behavior disorder (iRBD) is a prodromal stage of neurodegeneration and is associated with cortical dysfunction. The purpose of this study was to investigate the spatiotemporal characteristics of cortical activities underlying impaired visuospatial attention in iRBD patients using an explainable machine-learning approach.

METHODS

An algorithm based on a convolutional neural network (CNN) was devised to discriminate cortical current source activities of iRBD patients due to single-trial event-related potentials (ERPs), from those of normal controls. The ERPs from 16 iRBD patients and 19 age- and sex-matched normal controls were recorded while the subjects were performing visuospatial attentional task, and converted to two-dimensional images representing current source densities on flattened cortical surface. The CNN classifier was trained based on overall data, and then, a transfer learning approach was applied for the fine-tuning to each patient.

RESULTS

The trained classifier yielded high classification accuracy. The critical features for the classification were determined by layer-wise relevance propagation, so that the spatiotemporal characteristics of cortical activities that were most relevant to cognitive impairment in iRBD were revealed.

CONCLUSIONS

These results suggest that the recognized dysfunction in visuospatial attention of iRBD patients originates from neural activity impairment in relevant cortical regions and may contribute to the development of useful iRBD biomarkers based on neural activity.

Comparative efficacy of prolonged-release melatonin versus clonazepam for isolated rapid eye movement sleep behavior disorder

PURPOSE

Clonazepam and melatonin are recommended as first-line treatments for isolated rapid eye movement (REM) sleep behavior disorder (iRBD). This study aimed to compare their efficacy and safety in REM sleep without atonia (RWA) and RBD-related symptoms.

METHODS

This prospective, open-label, randomized trial included patients with video-polysomnography-confirmed iRBD. The patients were randomly assigned to receive either clonazepam 0.5 mg or prolonged-release (PR) melatonin 2 mg 30 min before bedtime for 4 weeks. The primary outcome was changes in RWA on follow-up polysomnography (PSG). Secondary endpoints were changes in other PSG parameters, clinical global improvement-impression scale (CGI-I) scores, and sleep questionnaire scores. The safety endpoint was adverse events.

RESULTS

Of 40 patients with probable RBD considered, 34 were enrolled in the study and randomized. Visual scoring parameters of RWA indices were reduced, and automatic scoring parameters tended to be improved after clonazepam treatment but not after PR melatonin treatment. The proportion of N2 sleep was increased, and N3 and REM sleep were decreased only in the clonazepam group. The clonazepam group tended to answer "much or very much improvement" on the CGI-I more frequently than the PR melatonin group (p = 0.068). Daytime sleepiness and insomnia symptoms were reduced after PR melatonin but not after clonazepam. Depressive symptoms increased after clonazepam. Four of the patients (13.3%) reported mild to moderate adverse events, which were similar between the two groups.

CONCLUSION

Four weeks of clonazepam, but not PR melatonin, improved RWA. RBD symptom improvement tended to be better after clonazepam than PR melatonin in exchange for increased depressive symptoms and daytime sleepiness.

CLINICALTRIALS

gov identifier: NCT03255642 (first submitted August 21, 2017).

Association of Nucleus Basalis of Meynert Functional Connectivity and Cognition in Idiopathic Rapid-Eye-Movement Sleep Behavior Disorder

Background and Purpose

Cognitive impairments are common in isolated rapid-eye-movement sleep behavior disorder (iRBD), in which the cholinergic system may play an important role. This study aimed to characterize the cortical cholinergic activity using resting-state functional connectivity (FC) of the nucleus basalis of Meynert (NBM) according to the cognitive status of iRBD patients.

Methods

In this cross-sectional study, 33 patients with polysomnography-confirmed iRBD and 20 controls underwent neuropsychological evaluations and resting-state functional magnetic resonance imaging. Thirteen of the iRBD patients had mild cognitive impairment (iRBD-MCI), and the others were age-matched patients with normal cognition (iRBD-NC). The seed-to-voxel NBM–cortical FC was compared among the patients with iRBD-MCI, patients with iRBD-NC, and controls. Correlations between average values of significant clusters and cognitive function scores were calculated in the patients with iRBD.

Results

There were group differences in the FC of the NBM with the left lateral occipital cortex and lingual gyrus (adjusted for age, sex, and education level). The strength of FC was lower in the iRBD-MCI group than in the iRBD-NC and control groups (each post-hoc p<0.001). The average NBM–lateral occipital cortex FC was positively correlated with the memory-domain score in iRBD patients.

Conclusions

The results obtained in this study support that cortical cholinergic activity is impaired in iRBD patients with MCI. FC between NBM and posterior regions may play a central role in the cognitive function of these patients.

Alerting network alteration in isolated rapid eye movement sleep behavior disorder patients with mild cognitive impairment

OBJECTIVE

Mild cognitive impairment (MCI) was found in 30-50% of the isolated REM sleep behavior disorder (iRBD) patients. Furthermore, it is known that patients with Parkinson's disease have attention network defects. Given that iRBD is known to be the prodromal disease of α-synucleinopathies, our aim was to investigate whether there are attention network dysfunctions in iRBD patients following the presence of MCI.

METHODS

14 healthy controls, 48 iRBD patients, 24 with MCI and 24 without MCI, were included in this study. Attention network task (ANT) was used to assess alerting, orienting, and executive control networks. Event-related potentials (ERPs) and behavioral performances were recorded during the ANT. Parietal N1 and P3 components were analyzed to find effects of the three attention networks.

RESULTS

IRBD patients without MCI showed neuropsychological, behavioral, and ERP results similar to those of healthy controls. On the other hand, iRBD patients with MCI showed a general decline in cognitive domains with no alerting effect (controls, p = 0.043; iRBD-noMCI, p = 0.014; iRBD-MCI, p = 0.130) while preserving orienting and executive control effect. Furthermore, iRBD patients with MCI had impairments in executive function and verbal memory domains, compared to iRBD patients without MCI.

CONCLUSIONS

Our findings indicate that when cognition is reduced to MCI levels in iRBD patients, the attention network, especially the alerting component, is impaired. The attention network and cognition, on the other hand, can be preserved in iRBD patients due to the compensatory mechanism.

Nonrapid eye movement sleep electroencephalographic oscillations in idiopathic rapid eye movement sleep behavior disorder: a study of sleep spindles and slow oscillations

STUDY OBJECTIVES

We investigated electroencephalographic (EEG) slow oscillations (SOs), sleep spindles (SSs), and their temporal coordination during nonrapid eye movement (NREM) sleep in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD).

METHODS

We analyzed 16 patients with video-polysomnography-confirmed iRBD (age, 65.4 ± 6.6 years; male, 87.5%) and 10 controls (age, 62.3 ± 7.5 years; male, 70%). SSs and SOs were automatically detected during stage N2 and N3. We analyzed their characteristics, including density, frequency, duration, and amplitude. We additionally identified SO-locked spindles and examined their phase distribution and phase locking with the corresponding SO. For inter-group comparisons, we used the independent samples t-test or Wilcoxon rank-sum test, as appropriate.

RESULTS

The SOs of iRBD patients had significantly lower amplitude, longer duration (p = 0.005 for both), and shallower slope (p < 0.001) than those of controls. The SS power of iRBD patients was significantly lower than that of controls (p = 0.002), although spindle density did not differ significantly. Furthermore, SO-locked spindles of iRBD patients prematurely occurred during the down-to-up-state transition of SOs, whereas those of controls occurred at the up-state peak of SOs (p = 0.009). The phase of SO-locked spindles showed a positive correlation with delayed recall subscores (p = 0.005) but not with tonic or phasic electromyography activity during REM sleep.

CONCLUSIONS

In this study, we found abnormal EEG oscillations during NREM sleep in patients with iRBD. The impaired temporal coupling between SOs and SSs may reflect early neurodegenerative changes in iRBD.

Working memory deficits in patients with idiopathic restless legs syndrome are associated with abnormal theta-band neural synchrony

Cognitive impairment, particularly prefrontal function, has been reported in patients with restless legs syndrome. However, working memory performance in patients with restless legs syndrome remains uncertain. The present study aimed to examine working memory performance in patients with restless legs syndrome by investigating electroencephalography theta-band oscillations within task-relevant brain regions and the synchronization among oscillations during a working memory task. Twelve female idiopathic patients with restless legs syndrome and 12 female healthy controls participated in this study. Nineteen-channel electroencephalography data were recorded while participants performed a Sternberg working memory task. We analysed event-related theta-band activity and interregional theta-band phase synchrony during the memory retrieval phase. The spatial pattern of theta-band phase synchrony was quantified using graph theory measures, including the clustering coefficient, characteristic path length, and small-world propensity. Considerable increases in theta-band activity and theta-band phase synchrony were observed at 600-700 ms in controls and at 650-750 ms in restless legs syndrome subjects after the probe item was presented. During this period, induced theta-band activity showed lower with borderline significance in the restless legs syndrome subjects than in the controls regardless of channel location (F_4,88  = 3.92, p = .06). Theta-band phase synchrony between the frontal and posterior regions was significantly reduced in the restless legs syndrome subjects. Inefficiency in both global and local networks in the restless legs syndrome subjects was revealed by the decreased small-world propensity (t₂₂  = 2.26, p = .03). Small-world propensity was negatively correlated with restless legs syndrome severity (r = -.65, p = .02). Our findings suggest that patients with restless legs syndrome have multiple deficits in cognitive processes, including attentional allocation, evaluation of incoming stimuli, and memory manipulation of encoded information during a working memory task. Abnormal local theta-band neural synchrony and global theta-band neural synchrony may underlie the neurophysiological mechanism of the working memory dysfunction associated with restless legs syndrome.

Altered insular functional connectivity in isolated REM sleep behavior disorder: a data-driven functional MRI study

OBJECTIVE

Functional connectivity (FC) changes can occur prior to structural changes. This study aimed to evaluate data-driven whole-brain FC associated with isolated rapid eye movement sleep behavior disorder (iRBD) using multivariate pattern analysis (MVPA).

METHODS

This was a cross-sectional study of 50 polysomnography-confirmed iRBD patients and 20 age- and sex-matched controls. We used MVPA implemented in the connectome-MVPA CONN toolbox to identify data-driven seed regions for post hoc seed-to-voxel connectivity analysis. The association between FC changes and clinical characteristics, including cognition, depression, autonomic function, and daytime sleepiness, was evaluated.

RESULTS

MVPA revealed one significant cluster located in the left posterior insular cortex. Seed-to-voxel FC analysis using the cluster as a seed showed significantly reduced FC with two clusters located in the precuneus in iRBD patients compared to the controls. The degree of FC was associated with the Montreal Cognitive Assessment-Korean version scores (r = 0.317, p = 0.025).

CONCLUSION

This study emphasizes the insula as an important neural correlate associated with iRBD that was associated with cognitive function.

Dynamic changes in nocturnal blood glucose levels are associated with sleep-related features in patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) has a bidirectional relationship with insulin resistance conditions; however, the mechanism remains unclear. This study aimed to compare dynamic nocturnal glucose changes among patients with OSA of varying levels of severity and evaluate temporal changes associated with the cardinal features of OSA (sympathetic hyperactivation, intermittent hypoxemia, and sleep fragmentation) in nondiabetic subjects. Nocturnal glucose was measured with a continuous glucose monitoring device every 5 min during polysomnography (PSG). The OSA features were evaluated using heart rate variability (HRV), minimum saturation, and electroencephalography. Eleven subjects with moderate to severe OSA and 12 subjects with no or mild OSA were evaluated. Those with moderate to severe OSA showed an increasing trend in blood glucose levels after sleep onset, whereas those without or with mild OSA showed a decreasing trend (F = 8.933, p < 0.001). Delta band power also showed different trends during sleep between the two groups (F = 2.991, p = 0.009), and minimum saturation remained lower in the moderate to severe OSA group than in the no or mild OSA group. High degrees of coupling between nocturnal glucose levels and each OSA feature were observed. Altered trends in nocturnal glucose in moderate to severe OSA may reflect glucose intolerance and result in metabolic consequences. Managing the features of sleep-related OSA may have implications for metabolic management in the future.

Abnormal activation of motor cortical network during phasic REM sleep in idiopathic REM sleep behavior disorder

Study Objectives

We investigated electroencephalography (EEG) power spectral density and functional connectivity during phasic and tonic rapid eye movement (REM) sleep, and examined any differences between patients with idiopathic REM sleep behavior disorder (iRBD) and controls.

Methods

EEG data from 13 people with iRBD (mean age, 66.3 years; men, 84.6%) and 10 controls (mean age, 62.3 years; men, 70%) were analyzed. We selected thirty 3 s miniepochs of both tonic and phasic REM sleep. We estimated relative power for six frequency bands. For functional connectivity analysis, we calculated weighted phase lag index (wPLI) and conducted pairwise comparisons between the two groups.

Results

EEG power spectral analysis revealed significant interactions between the REM sleep state (phasic vs. tonic) and group at sigma (p = 0.009) and beta (p = 0.002) bands. Sigma- and beta-power decrease during phasic REM sleep was more pronounced and extensive in people with iRBD than in controls. Regarding functional connectivity, there were significant interactions between the REM sleep state and group at alpha (p = 0.029), sigma (p = 0.047), beta (p = 0.015), and gamma (p = 0.046) bands. The average wPLI was significantly higher during phasic REM sleep than during tonic REM sleep, which was observed in people with iRBD but not in controls. The altered functional connections mainly involved the frontal and parietal regions at beta and gamma bands.

Conclusions

Our findings provide neurophysiological evidence for pathological motor cortex activation during phasic REM sleep which may be associated with generation of dream-enacting behaviors in iRBD.

Impaired slow oscillation, sleep spindle, and slow oscillation-spindle coordination in patients with idiopathic restless legs syndrome

OBJECTIVES

Thalamocortical abnormalities have been implicated in the pathophysiology of restless legs syndrome (RLS). We hypothesized that sleep spindle and slow oscillation (SO) activity is impaired in RLS, and that this dysfunction may contribute to sleep disturbance in these patients. To address this issue, we characterized sleep spindle and SO activity in RLS.

METHODS

Fifteen drug-naive, idiopathic RLS patients (13 female and 2 male) and 15 female healthy controls participated in this study. Nineteen-channel electroencephalograms were obtained during polysomnographic (PSG) recordings. An automated sleep spindle and SO detection algorithm was used to detect sleep spindle (12-16 Hz) and SO (<1 Hz) activity. The quantitative characteristics of sleep spindle and SO activity were investigated.

RESULTS

Compared with the healthy controls, in RLS patients, we observed density and power reduction in sleep spindles. In SOs, density reduction and duration increment were shown in RLS patients. In addition, SO-spindle coordination was deficient in RLS as revealed by reduced SO locked spindle power, dispersed and delayed spindle phase, and decreased SO-spindle coupling. Although sleep spindle power was negatively correlated with wake after sleep onset (WASO) time, SO duration was positively correlated with the arousal index in RLS.

CONCLUSIONS

Our study suggests that sleep disturbances may be mediated by a combined deficit in spindle and SO activity and SO-spindle coordination. The abnormal SO and spindle activity observed in RLS support the notion that thalamocortical abnormalities underlie this condition and may promote disturbed sleep integrity.

3334Updated meta-analysis of biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent implantations

Background

Data regarding clinical outcomes of biodegradable polymer drug-eluting stent (BP-DES) versus second-generation durable polymer drug-eluting stent (DP-DES) in patients undergoing percutaneous coronary intervention (PCI) are inconclusive.

Purpose

We aimed to perform a meta-analysis to investigate the clinical outcomes of BP-DES compared with second-generation DP-DES in patients who have undergone PCI.

Methods

We searched PubMed, MEDLINE, EMBASE, and Cochrane databases through January 2019 for randomized controlled trials comparing BP-DES with second-generation DP-DES in patients treated with PCI. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), definite/probable stent thrombosis (ST) were compared between the groups. Additionally, a landmark analysis with the landmark set at 1 year and a subgroup analysis according to stent characteristics were performed.

Results

Data from 23 trials including 28802 randomized patients were analyzed. At a median follow up of 3.1 years, no significant differences were found in terms of all-cause death (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.95–1.16), cardiac death (OR 1.01, 95% CI 0.87–1.17), MI (OR 0.92, 95% CI 0.82–1.03), TVR (OR 0.97, 95% CI 0.86–1.11), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.86, 95% CI 0.70–1.07) between the groups. Landmark analysis showed that there were similar risks in all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.92, 95% CI 0.67–1.28) between the groups. The similar tendency of any study endpoints between the groups was consistent in the subgroup, including stent platform (stainless steel vs. alloy), the drug coating distribution (abluminal vs. circumferential), the polymer degradation period (<6 months vs. >6 months), or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the uses of BP-DES with sirolimus-eluting (OR 0.84, 95% CI 0.72–0.98) or ultrathin strut (defined as <70μm; OR 0.81, 95% CI 0.68–0.97) were predictive for lower risk of MI.

Clinical outcomes

Conclusions

In our updated meta-analysis, BP-DES implantation was associated with comparable clinical outcomes compared with second-generation DP-DES implantation. However, PCI with ultrathin biodegradable polymer sirolimus-eluting stent could reduce the risk of MI.

P3127Optimal revascularization strategy in non-ST-segment elevation myocardial infarction with multivessel coronary artery disease: staged vs. one-time vs. culprit-only revascularization

Background/Introduction

Although optimal revascularization strategy in patients with ST-segment elevation myocardial infarction with multivessel coronary artery disease (MVD) was well established, there are few studies which investigated optimal revascularization strategy in non-ST-segment elevation myocardial infarction (NSTEM) with MVD.

Purpose

We investigated 2-year clinical outcomes according to strategy of revascularization in patients with NSTEMI and MVD.

Methods

Between November 2011 and October 2015, a total of 2474 patients with NSTEMI and MVD who underwent successful percutaneous coronary intervention were analyzed from the Korea Acute Myocardial Infarction Registry-National Institute of Health (staged 308, one-time 1043 and culprit-only 1123 patients). We did not include patients with left main disease and cardiogenic shock. Primary endpoint was major adverse cardiac events (MACE: the composite of cardiac death, myocardial infarction [MI] or target-vessel revascularization [TVR]) during 2-year follow-up (median 737 days [interquartile range 705–764]). We also analyzed the of all-cause mortality, stroke and non-TVR.

Results

Baseline characteristics such as age, gender, and prevalence of atherosclerotic risk factors between multivessel revascularization (MVR; staged or one-time revascularization) and CVR were similar. There was also no difference in symptom to balloon time in 2 groups. MACE occurred in 305 patients (12.3%) during 2-year follow-up. MVR could reduce incidence of MACE (10.2% vs. 14.9%; adjusted hazard ratio [HR] 1.50 for CVR, 95% confidence interval [CI] 1.20–1.88, p<0.001), all-cause death (8.4% vs. 12.1%; adjusted HR 1.45 for CVR, 95% CI 1.13–1.87, p=0.003) and non-TVR (1,9% vs. 7.0%; adjusted HR 3.99 for CVR, 95% CI 2.55–6.27, p<0.001). There was no difference in incidence of stroke between MVR and CVR. We also analyzed same analysis between staged and one-time revascularization. Complete revascularization was more achieved in one-time revascularization group compared to staged revascularization group (62.0% vs. 76.1%, p<0.001). In multivariate Cox-regression analysis, staged revascularization was not associated with improved clinical outcomes in terms of MACE (HR 0.74, 95% CI 0.50–1.09, p=0.126), all-cause death (HR 1.07, 95% CI 0.69–1.68, p=0.759), stroke (HR 1.75, 95% CI 0.68–4.52, p=0.245) and non-TVR (HR 2.56, 95% CI 0.75–8.68, p=0.132). Analysis by propensity score matching and inverse probability of treatment weighting did not significantly affect the results.

Conclusions

MVR reduced 2-year adverse cardiac events in patients with NSTEMI and MVD compared to CVR. However, staged revascularization was not superior to one-time revascularization for reducing MACE among NSTEMI patients with MVD who received MVR.

P2799Long-term outcomes after percutaneous coronary intervention with biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent: evidence from a meta-analysis

Background

The true benefit of biodegradable polymer drug-eluting stent (BP-DES) over second-generation durable polymer drug-eluting stent (DP-DES) expected to be represented during late period of follow-up after percutaneous coronary intervention (PCI), but prior meta-analysis only evaluated short-term outcomes.

Purpose

We aimed to compare the long-term clinical outcomes after PCI with BP-DES versus second-generation DP-DES by a meta-analysis of randomized controlled trials.

Methods

Randomized controlled trials comparing BP-DES with second-generation DP-DES implantations were searched through PubMed, MEDLINE, EMBASE, and Cochrane databases. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), and definite/probable stent thrombosis (ST) were compared between the groups. In addition, a landmark analysis with the landmark set at 1-year and a subgroup analysis based on stent characteristics were performed.

Results

Fifteen trials that included a total of 21311 randomized patients with at least 2 years follow-up were analyzed. At a median follow-up of 4.2 years, no significant differences in the risks of all-cause death (odds ratio [OR] 1.03, 95% confidence interval [CI] 0.94–1.14), cardiac death (OR 1.03, 95% CI 0.88–1.20), MI (OR 0.90, 95% CI 0.79–1.01), TVR (OR 0.96, 95% CI 0.82–1.12), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.84, 95% CI 0.67–1.05) were found between the groups. In the 1-year landmark analysis, the rates of all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.94, 95% CI 0.67–1.31) were similar between the groups. There were comparable rates of any study endpoints between the groups regardless of stent platform (stainless steel vs. alloy), the polymer degradation period (<6 months vs. >6 months) or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the use of BP-DES with sirolimus eluting (OR 0.82, 95% CI 0.70–0.97), circumferential drug distribution (OR 0.79, 95% CI 0.65–0.96), thin strut (defined as <100μm; OR 0.83, 95% CI 0.70–0.97), or ultrathin strut (defined as <70μm; OR 0.78, 95% CI 0.64–0.94) were associated with lower rates of MI than did second-generation DP-DES. Moreover, BP-DES with circumferential drug distribution (OR 0.82, 95% CI 0.69–0.98) was predictive for reduced rates of TVR.

Clinical outcomes

Conclusions

In this meta-analysis, long-term clinical outcomes were equivalent between BP-DES and second-generation DP-DES implantations. However, among BP-DESs, the improved risks of MI in those with sirolimus eluting, circumferential drug distribution, thin strut, or ultrathin strut and decreased rates of TVR in those with circumferential drug distribution were noted.

Impaired visuospatial attention revealed by theta- and beta-band cortical activities in idiopathic REM sleep behavior disorder patients

OBJECTIVES

Idiopathic REM sleep behavior disorder (iRBD) patients are susceptible to cognitive deficits, especially attention dysfunction. The objective of this study is to elucidate the neural mechanism of the dysfunction in attention known as 'inhibition of return' (IOR) in iRBD patients based on an analysis of oscillatory cortical activity during a selective attention task.

METHODS

Event-related potentials (ERPs) were recorded from iRBD patients and normal control subjects while performing a Posner task. The differences in N1 ERP and theta- and beta-bands event-related spectral perturbations (ERSPs) between valid and invalid stimuli were compared between groups.

RESULTS

The N1 amplitude was significantly higher for the invalid stimuli in controls, while the valid-invalid difference was not significant in iRBD patients. The valid-invalid differences in ERSPs were prominent in controls at ∼100-400 ms for the theta-band and ∼200-400 ms for the beta-band, and the valid-invalid differences in ERSPs were not significant in the iRBD patients.

CONCLUSION

The results demonstrated that valid-invalid differences in neural activity were absent in iRBD patients, and these neural findings were in accord with the behavioral results.

SIGNIFICANCE

Our findings imply impairment in sensory-perceptual processing mediated by attentional control and response inhibition in early-stage iRBD before clinical neurodegeneration.

Spatiotemporal Analysis of Event-related Current Density Reveals Dissociable Effects of Arousal and Valence on Emotional Picture Processing

BACKGROUND

The processing of emotional visual stimulation involves the processing of emotional and visuoperceptual information. It is not completely revealed how the valence and arousal affect these two aspects. The objective was to investigate the effects of valence and arousal on spatiotemporal characteristics of cortical information processing using distributed source imaging of event-related current density (ERCD).

METHODS

Electroencephalograms (64 channels) were recorded from 19 healthy men while presenting affective pictures. Distributed source localization analysis was adopted to obtain the spatiotemporal pattern of ERCD on cortical surface in response to emotional visual stimulation. A nonparametric cluster-based permutation test was used to find meaningful time and space without prior knowledge.

RESULTS

Significant changes of ERCD in 400-800 ms among positive, negative, and neutral emotional conditions were found in left posterior cingulate cortex (PCC) and right inferior temporal cortex (ITC). In the PCC, the stimuli with higher arousal levels showed more negative ERCD than neutral stimuli. In the ITC, the ERCD for negative stimuli was significantly more negative than those of positive and neutral ones.

CONCLUSION

Arousal and valence had strong influence on memory encoding and visual analysis at late period. The location and time showing significant change in neural activity according to arousal and valence would provide valuable information for understanding the changes of cortical function by neuropsychiatric disorders.

Altered Functional Connectivity in Idiopathic Rapid Eye Movement Sleep Behavior Disorder: A Resting-State EEG Study

Study Objectives

Idiopathic rapid eye movement sleep behavior disorder (iRBD) is considered as a prodromal stage of synucleinopathy. Although loss of functional connectivity is implicated in neurodegenerative diseases, network characteristics of electroencephalography (EEG) in iRBD are unknown. Therefore, we evaluated resting-state EEG functional connectivity to identify the brain network changes in patients with iRBD.

Methods

We prospectively enrolled 20 patients with polysomnography-confirmed iRBD and 16 controls. Four patients with mild cognitive impairment were excluded from the analysis after cognitive function tests. EEG was recorded during relaxed wakefulness. We computed the weighted phase lag index as a measure of functional connectivity from EEG recordings.

Results

All patients with iRBD (mean age 64.3 years; men, 68.8%) had no overt manifestations of neurodegenerative diseases such as Parkinsonism or dementia. The mean duration from symptom onset was 4.8 years. Overall connectivity strength did not differ between the two groups in all frequency bands. However, comparisons of each functional connection with the nonparametric permutation test demonstrated iRBD had decreased delta-band functional connectivity in the frontal regions. There were no significantly increased functional connections in all frequencies. The altered connections had a significant correlation with RBD questionnaire scores. Notably, delta-band weighted phase lag index between left frontal and central regions was correlated with verbal fluency performance (r = 0.486, p = .007).

Conclusions

Resting-state brain network of iRBD was characterized by a loss of delta-band functional connectivity. Therefore, functional networks in iRBD are altered at the early phase of disease.

Event-related Desynchronization of Mu Rhythms During Concentric and Eccentric Contractions

The purpose of this study was to compare the electroencephalographic (EEG) patterns and reaction times (RTs) of muscle activation between concentric and eccentric biceps brachii contractions under the RT paradigm and to evaluate how the EEG patterns and RTs changed with practice. Sixteen subjects performed 3 sets of 30 repetitions of submaximal voluntary concentric and eccentric biceps contractions. RT, event-related desynchronization (ERD) patterns of mu rhythm onset, and ERD amplitudes were selectively analyzed. Mental demand decreased as familiarity with the motor action increased due to practice regardless of contraction type. However, the 2 types of muscle contractions still have differences in brain activity regardless of decreased mental demand: eccentric contractions require earlier preparation than concentric contractions.

Abnormal Sleep Delta Rhythm and Interregional Phase Synchrony in Patients with Restless Legs Syndrome and Their Reversal by Dopamine Agonist Treatment

Background and Purpose

The purpose of this study was to characterize abnormal cortical activity during sleep in restless legs syndrome (RLS) patients and to determine the effects of treatment with a dopamine agonist. Based on whole-brain electroencephalograms, we attempted to verify alterations in the functional network as well as the spectral power of neural activities during sleep in RLS patients and to determine whether the changes are reversed by treatment with pramipexole.

Methods

Twelve drug-naïve RLS patients participated in the study. Overnight polysomnography was performed before and after treatment: the first recording was made immediately prior to administering the first dose of pramipexole, and the second recording was made 12–16 weeks after commencing pramipexole administration. Sixteen age-matched healthy participants served as a control group. The spectral power and interregional phase synchrony were analyzed in 30-s epochs. The functional characteristics of the cortical network were quantified using graph-theory measures.

Results

The delta-band power was significantly increased and the small-world network characteristics in the delta band were disrupted in RLS patients compared to the healthy controls. These abnormalities were successfully treated by dopaminergic medication. The delta-band power was significantly correlated with the RLS severity score in the RLS patients prior to treatment.

Conclusions

Our findings suggest that the spectral and functional network characteristics of neural activities during sleep become abnormal in RLS patients, and these abnormalities can be successfully treated by a dopamine agonist.

Difficulty-related changes in inter-regional neural synchrony are dissociated between target and non-target processing

The major purpose of this study was to explore the changes in the local/global gamma-band neural synchronies during target/non-target processing due to task difficulty under an auditory three-stimulus oddball paradigm. Multichannel event-related potentials (ERPs) were recorded from fifteen healthy participants during the oddball task. In addition to the conventional ERP analysis, we investigated the modulations in gamma-band activity (GBA) and inter-regional gamma-band phase synchrony (GBPS) for infrequent target and non-target processing due to task difficulty. The most notable finding was that the difficulty-related changes in inter-regional GBPS (33-35 Hz) at P300 epoch (350-600 ms) completely differed for target and non-target processing. As task difficulty increased, the GBPS significantly reduced for target processing but increased for non-target processing. This result contrasts with the local neural synchrony in gamma-bands, which was not affected by task difficulty. Another major finding was that the spatial patterns of functional connectivity were dissociated for target and non-target processing with regard to the difficult task. The spatial pattern for target processing was compatible with the top-down attention network, whereas that for the non-target corresponded to the bottom-up attention network. Overall, we found that the inter-regional gamma-band neural synchronies during target/non-target processing change significantly with task difficulty and that this change is dissociated between target and non-target processing. Our results indicate that large-scale neural synchrony is more relevant for the difference in information processing between target and non-target stimuli.

Comparison of laboratory detection methods of aspirin resistance in coronary artery disease patients

Aspirin reduces the prevalence of nonfatal myocardial infarction, stroke, and death by 25.0% in high risk group of patients with cardiovascular disease. Previous studies have estimated that about 5.5-56.8% of the population are aspirin resistant. The mechanisms of aspirin resistance (AR) have not been fully understood. We compared the detection methods for AR using traditional platelet aggregometry and VerifyNow system. One hundred and seventy-two coronary artery disease patients who had taken aspirin only or combinations with aspirin and clopidogrel for over 7 days were included. Of the 55 patients with aspirin only, aggregometer detected six AR (10.9%) and VerifyNow identified 10 AR (18.2%) cases. Among 117 patients with combined therapy, none (0.0%) and 10 (8.5%) of AR were detected by aggregometer and VerifyNow, respectively. There were six (3.4%) patients of AR defined by both methods and they all received aspirin monotherapy. Although the correlation between the aggregometry and VerifyNow was low, with defined criteria both methods gave 91.9% agreement to find AR. VerifyNow showed a higher sensitivity to detect AR. Further studies are required to biologically define AR and to alter therapy based on platelet function tests.

Chip- and board-level optical interconnections using rigid flexible optical electrical printed circuit boards

A new optical interconnection scheme based on a rigid flexible optical electrical printed circuit board (RFOE-PCB) is suggested. The easily installed RFOE-PCB can be universally applied for both chip- and board-level optical interconnections. This letter describes the detailed fabrication process, optical properties, and heat-resisting property of the RFOE-PCB. The fabricated RFOE-PCB was also successfully demonstrated with a 2.5-Gb/s data transmission through a 45 degrees-ended optical waveguide embedded in the RFOE-PCB.

Nonselective left internal mammary artery angiography during right transradial coronary angiography: a simple, rapid, and safe technique

Internal mammary artery angiography is increasingly required, but the technique for left internal mammary artery (LIMA) angiography during right transradial coronary angiography is not well established. The authors investigated the feasibility and safety of a new, simple, and rapid nonselective technique. Following right transradial coronary angiography, LIMA angiography was performed using a 5 French (Fr) Judkins JL-3.5 catheter in 110 patients. The catheter, placed in the ascending aorta with its natural curve, was withdrawn slowly while being rotated clockwise to engage its tip in the proximal left subclavian artery. Contrast material was injected while sphygmomanometer cuff inflation was applied to the left upper arm. In the last 50 patients, the angiography was performed twice randomly with and without the cuff inflation. In 108 patients (98%), the catheter was successfully engaged in the subclavian artery in a mean of 11 +/- 8 seconds (range, 3-136) from the time when it was withdrawn from the ascending aorta, and nonselective LIMA angiography was successfully performed. The image quality of the angiograms was satisfactory in 103 (95%) of the 108 patients. In the last 50 patients, the image quality of the angiograms was determined satisfactory in 48 (96%) and 45 (90%) patients, with and without the cuff inflation, respectively. The difference was statistically not significant. There were no complications, including arterial dissection and thromboembolism. In conclusion, nonselective LIMA angiography can be readily and safely performed during right transradial coronary angiography using a 5 Fr Judkins JL-3.5 catheter.

Bilateral selective internal mammary artery angiography via right radial approach: clinical experience with newly designed Yumiko catheter

The radial artery has been increasingly used as a primary access site for coronary angiography and intervention. But the technique for internal mammary artery (IMA) visualization via the right radial artery has not been well described. Therefore, the study was conducted to investigate the feasibility, safety, and adequacy of selective bilateral IMA angiography via the right radial artery using the recently developed Yumiko catheter. From November 1999 to October 2000, both IMA angiographies were undertaken immediately following the diagnostic coronary angiogram taken from right transradial approach in 114 patients. IMA angiography was successfully obtained in 99% (113/114) patients. For left IMA angiography, 73 (64%), 28 (25%), and 12 (11%) imagings were obtained in a selective, a semiselective, and a nonselective way, respectively. After initial periods of 33 left-IMA-only imaging, right IMA angiography was obtained in 81 patients (phase 2). Selective right IMA imaging was done in 73 (90%), semiselective in 6, and nonselective in 2 patients. The reasons for failure of selective or semiselective visualization were severe vascular tortuosity, far distal anatomical origin of left IMA and ulcerative plaque, or acutely angled left subclavian artery. The feasibility and safety of selective and semiselective bilateral IMA angiography were demonstrated using a 5 Fr Yumiko catheter from the right radial approach. Cathet Cardiovasc Intervent 2001;54:19-24.

Combined right transradial coronary angiography and selective carotid angiography: safety and feasibility in unselected patients

We evaluated the safety and feasibility of ad hoc carotid angiography following the right transradial coronary angiography. Selective carotid angiography was performed subsequent to coronary angiography in 213 consecutive patients. A 5 Fr Simmons catheter was reformed in descending or ascending aorta, then, withdrawn and rotated to cannulate the left and right carotid artery. Both carotid angiography was performed selectively in 211 (99%) patients. In two patients with severely tortuous subclavian artery, selective cannulation of the left carotid artery failed. There was no thromboembolism or arterial dissection. After the learning phase of 50 patients, the time to reform the catheter in aorta and to cannulate the left and right carotid artery was 50 +/- 77, 66 +/- 68, and 58 +/- 57 sec, respectively. Total procedural time was 195 +/- 145 sec. In conclusion, ad hoc carotid angiography can be performed reliably and safely following the right transradial coronary angiography. It might be useful for evaluation of an isolated or associated carotid artery stenosis. Cathet Cardiovasc Intervent 2001;53:380-385.

Retrieval of dislodged and disfigured transradially delivered coronary stent: report on a case using forcep and antegrade brachial sheath insertion

We report a case of dislodged and damaged stent during transradial coronary procedure using 6 Fr device, which was successfully retrieved by using a forcep and 8 Fr antegrade brachial sheath. The disfigured and bulky stent can be removed, after their retrieval from the coronary circulation, using a forcep inserted through an 8 Fr brachial artery sheath if the radial artery is deemed too small to accommodate larger sheath.

Primary stenting for acute myocardial infarction via the transradial approach: a safe and useful alternative to the transfemoral approach

BACKGROUND

Primary stenting in acute myocardial infarction (AMI) has been demonstrated to reduce recurrent ischemic events. However, transradial stenting in AMI has not been well established. Therefore, we sought to investigate the feasibility and utility of transradial coronary stenting in patients with AMI.

METHODS

From April 1998 to April 1999, 56 patients (43 male; mean age of 57 years) who arrived within 6 hours of pain onset with culprit vessel size > 2.5 mm constituted this study. The transradial approach (Group 1) was used in 30 patients with hemodynamically stable and palpable right radial pulse. The transfemoral approach (Group 2) was used for vascular access in the remainder of patients (26) who might have required a second vascular access site for intraaortic balloon pumping (in cardiogenic shock) and/or a transvenous temporary pacemaker.

RESULTS

Overall success rate was achieved in 54 of 56 patients (96%). The success rate was 90% (27/30) in Group 1 and 96% (25/26) in Group 2. The cannulation time (from patient arrival at the catheterization room to the time of arterial cannulation) and the total procedure time (from patient arrival at the catheterization room to the completion of the procedure) were not significantly different between Group 1 and Group 2 (9.2+/-5.3 versus 8.9+/-5. 8 minutes, p>0.05; 53.7+/-19.4 versus 57.5 +/-26.8 minutes, p>0.05, respectively). In the Group 1 patients, there was no forearm ischemia or loss of radial pulse during the 30-day follow-up period.

CONCLUSION

Primary coronary stenting for acute myocardial infarction via the transradial approach is a safe and feasible alternative to the conventional transfemoral approach, and is especially useful for hemodynamically stable patients who do not require a second vascular access site.

Successful inoue balloon mitral commissurotomy in double-orifice mitral stenosis

We report a rare case of stenotic double-orifice mitral valve of incomplete bridge type in a 40-year-old male. The fibrous bridge tissue between the leaflets was successfully split with a 24-mm Inoue balloon catheter using the stepwise dilation technique. Cathet. Cardiovasc. Intervent. 49:200-203, 2000.

Determination of free acetaldehyde in total blood for investigating the effect of aspartate on metabolism of alcohol in mice

To explore the effect of sodium L-aspartate monohydrate (aspartate) as a NAD+ regenerating agent for acetaldehyde in alcohol metabolism, a simple HPLC method has been developed for the measurement of free acetaldehyde in total mice blood digested with alcohol and aspartate. The blood samples were collected in EDTA Vacutainer tubes, and treated with 2,4-dinitrophenylhydrazine (DNP hydrazine) reagent in total blood. Acetaldehyde DNP hydrazone was extracted from total blood and analyzed by HPLC using an Ultrasphere ODS column. The compounds were separated using acetonitrile-water (50:50, v/v) as mobile phase and detected at 356 nm. The detection limit for acetaldehyde DNP hydrazone was 0.1 ppm. A blank determination was carried out for each analysis and subtracted from the results. The amount of acetaldehyde in blood has been determined as a function of time lapse after sole alcohol administration and aspartate ingestion followed by alcohol administration, respectively. This comparative analysis demonstrates that the ingestion of aspartate before the administration of alcohol dramatically decreases the aldehyde level in blood, and aspartate may be utilized as a prospective antagonist for acceleration of ethanol metabolism and prevention of acetaldehyde toxicity.

Atrial fibrillation in patients with permanent VVI pacemakers: risk factors for atrial fibrillation

OBJECTIVES

Atrial fibrillation (AF) does not only deteriorate the cardiac function and increases the thromboembolic risk but also triggers rapid and irregular ventricular rhythm in patients with atrial synchronous pacing. However, the risk factors for the development of AF in patients with pacemakers are not clearly determined yet. The present study was designed to determine the risk factors for AF in patients with VVI pacemakers.

METHODS

This study included 80 patients (41 sick sinus syndrome, 39 AV block) who were followed for more than 6 months or developed AF regardless of the duration of follow-up after implantation of VVI pacemakers. Patients were divided into two groups according to whether or not AF developed during follow-up (mean: 25.7 +/- 2.5 months): group A developed AF and group B did not. The underlying arrhythmias, cardiovascular risk factors, left atrial size, characteristics of P wave were compared between the two groups.

RESULTS

The mean age of the patients was 58.9 +/- 11.4 years and 28 (35%) were male. AF developed in 13 (16.3%) of 80 patients with VVI pacemakers. Sick sinus syndrome (SSS) as an underlying arrhythmia was significantly more frequent in group A than group B (84.6% vs. 44.8%, p < 0.01). P wave width was greater in group A (127.6 +/- 24.8 ms) than in group B (110.7 +/- 17 ms) (p < 0.05). There was, however, no significant difference in cardiovascular risk factors, left atrial size, P wave axis and amplitude between the two groups.

CONCLUSION

These results suggest that sinus node dysfunction and intra-atrial conduction delay may be the risk factors for AF in patients with VVI pacemakers. Further studies are needed to determine how sick sinus syndrome and intra-atrial conduction delay increase the risk for AF in patients with VVI pacemakers.

Interrupted circular suture: bleeding control during cesarean delivery in placenta previa accreta

Rapid accumulation of blood from the placental separation site during cesarean delivery for placenta previa obscures the surgical field and quickly leads to deterioration of the patient's vital signs. We used the following technique in eight cases of intractable bleeding among 49 cesareans for placenta previa. Following failure to control the bleeding by suture at the placental separation site via the lower segment cesarean incision, the vessels were ligated using interrupted 2-3-cm sutures at 1-cm intervals in a circle around the bleeding area on the serosal surface of the uterus. The sutures were placed as deeply as possible in order to reach the endometrium. This led to a marked decrease in bleeding and allowed the small vessels to be easily identified and ligated. The amount of blood transfused and the operation time were gradually reduced as we became adept in the use of this procedure. Our experience suggests that this technique could reduce the use of hysterectomy in cesarean for placenta previa.

Body stalk anomaly--a case report

A case is presented of an amnionic rupture sequence which led to massive fetal ventral herniation and lordoscoliosis. Characteristic ultrasonographic findings of an omphalocele, fetal attachment to the placenta, and the absence of free-floating umbilical cord were observed.

An unusual venous anomaly of the placenta

The authors present an unusual vascular anomaly of the placenta. The placenta was very large, weighing 1,490 g. On the fetal surface, numerous dilated and tortuous vessels were observed on and under the chorionic membrane, of which three branches arose from a vein that was connected to the umbilical vein. One of them had a 5 x 2.5 cm aneurysmal dilatation, where three secondary branches arose. These venous channels were dilated and tortuous. The longest secondary branch was 133 cm in length and 1.2 cm in mean diameter and led into the placenta. Multiple, severely coiled or straight small branches arising from these vessels were also observed as vascular tangles. Some of these smaller vessels also led into the placenta. All abnormal vessels were veins. The umbilical cord was also normal except for a membranous insertion, and the placenta was unremarkable except for its large size.

Window operation: an alternative treatment method for Bartholin gland cysts and abscesses

Recently, we developed the "window operation" as a more effective way to treat Bartholin gland cysts and abscesses. The window operation was used to treat 25 Bartholin cysts and 22 Bartholin abscesses during a 3-year period from October 1, 1986 to September 30, 1989. Under local anesthesia, a small piece of skin including the cyst wall was excised in an oval shape, and suturing was performed along the excised margin. Postoperative antibiotics were given in cases of acute inflammation. A new mucocutaneous junction was observed at the 4-week postoperative checkup. No complications or recurrences have been observed during the study period. The window operation can be an alternative method of treatment for Bartholin gland cysts or abscesses.