MobCovid: Confirmed Cases Dynamics Driven Time Series Prediction of Crowd in Urban Hotspot.

Monitoring the crowd in urban hot spot has been an important research topic in the field of urban management and has high social impact. It can allow more flexible allocation of public resources such as public transportation schedule adjustment and arrangement of police force. After 2020, because of the epidemic of COVID-19 virus, the public mobility pattern is deeply affected by the situation of epidemic as the physical close contact is the dominant way of infection. In this study, we propose a confirmed case-driven time-series prediction of crowd in urban hot spot named MobCovid. The model is a deviation of Informer, a popular time-serial prediction model proposed in 2021. The model takes both the number of nighttime staying people in downtown and confirmed cases of COVID-19 as input and predicts both the targets. In the current period of COVID, many areas and countries have relaxed the lockdown measures on public mobility. The outdoor travel of public is based on individual decision. Report of large amount of confirmed cases would restrict the public visitation of crowded downtown. But, still, government would publish some policies to try to intervene in the public mobility and control the spread of virus. For example, in Japan, there are no compulsory measures to force people to stay at home, but measures to persuade people to stay away from downtown area. Therefore, we also merge the encoding of policies on measures of mobility restriction made by government in the model to improve the precision. We use historical data of nighttime staying people in crowded downtown and confirmed cases of Tokyo and Osaka area as study case. Multiple times of comparison with other baselines including the original Informer model prove the effectiveness of our proposed method. We believe our work can make contribution to the current knowledge on forecasting the number of crowd in urban downtown during the Covid epidemic.

Novel indicator for the spread of new coronavirus disease 2019 and its association with human mobility in Japan.

The Japanese government adopted policies to control human mobility in 2020 to prevent the spread of severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). The present study examined the impact of human mobility on COVID-19 cases at the prefectural level in Japan by devising an indicator to have a relationship between the number of infected people and on human mobility. We calculated origin-destination travel mobility within prefectures in Japan from March 1st to December 31st, 2020, using mobile phone data. A cross-correlation function (CCF) was used to examine the relationship between human mobility and a COVID-19 infection acceleration indicator (IAI), which represents the rate of change in the speed of COVID-19 infection. The CCF of intraprefectural human mobility and the IAI in Tokyo showed a maximum value of 0.440 at lag day 12, and the IAI could be used as an indicator to predict COVID-19 cases. Therefore, the IAI and human mobility during the COVID-19 pandemic were useful for predicting infection status. The number of COVID-19 cases was associated with human mobility at the prefectural level in Japan in 2020. Controlling human mobility could help control infectious diseases in a pandemic, especially prior to starting vaccination.

The impact of declaring the state of emergency on human mobility during COVID-19 pandemic in Japan.

Background/objectives: Japan has responded to the spread of COVID-19 through declaration of a state of emergency to regulate human mobility. Although the declaration was enforced by the government for prefectures, there is limited evidence as to whether the public complied with requests for voluntary stay at home. In this study, we evaluated the impact of declaring a state of emergency on human mobility during the COVID-19 pandemic in Japan. Methods: We utilized daily human mobility data for 47 prefectures in Japan. Data were collected via mobile phone from February 1, 2020 to April 30, 2021. Difference-in-difference analysis was utilized to estimate the effects of the declaration of a state of emergency on prefectures in the Tokyo Metropolitan Area (Tokyo, Kanagawa, Saitama, and Chiba) in comparison to other prefectures where the state of emergency was first lifted (Osaka, Hyogo, Fukuoka, and Aichi). Results: Human mobility was suppressed during the second state of emergency, from January 8 to March 21, 2021. However, the impact was weaker for the second state of emergency compared to the first. Conclusion: In Japan, government requests for stay at home, such as the declaration of a state of emergency, were temporarily able to control human mobility. However, the second state of emergency was not as effective as the first. If additional need to regulate human mobility arises, self-restraint with stronger enforcement should be considered.

Changes in social environment due to the state of emergency and Go To campaign during the COVID-19 pandemic in Japan: An ecological study.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic in Japan, the state of emergency, as a public health measure to control the spread of COVID-19, and the Go To campaign, which included the Go To Travel and Go To Eat campaigns and was purposed to stimulate economic activities, were implemented. This study investigated the impact of these government policies on COVID-19 spread. METHODS: This ecological study included all 47 prefectures in Japan as samples between February 3 and December 27, 2020. We used COVID-19 cases and mobility as variables. Additionally, places where social contacts could accrue, defined as restaurants, companies, transportation, and tourist spots; mean temperature and humidity; the number of inhabitants in their twenties to fifties; and the number of COVID-19 cases in the previous period, which were factors or covariates in the graphical modeling analysis, were divided into five periods according to the timing of the implementation of the state of emergency and Go To campaign. RESULTS: Graphical changes occurred throughout all five periods of COVID-19. During the state of emergency (period 2), a correlation between COVID-19 cases and those before the state of emergency (period 1) was observed, although this correlation was not significant in the period after the state of emergency was lifted (period 3). During the implementation of Go To Travel and the Go To Eat campaigns (period 5), the number of places where social contacts could accrue was correlated with COVID-19 cases, with complex associations and mobility. CONCLUSIONS: This study confirms that the state of emergency affected the control of COVID-19 spread and that the Go To campaign led to increased COVID-19 cases due to increased mobility by changing behavior in the social environment where social contacts potentially accrue.

On-site Dining in Tokyo During the COVID-19 Pandemic: Time Series Analysis Using Mobile Phone Location Data.

BACKGROUND: During the second wave of COVID-19 in August 2020, the Tokyo Metropolitan Government implemented public health and social measures to reduce on-site dining. Assessing the associations between human behavior, infection, and social measures is essential to understand achievable reductions in cases and identify the factors driving changes in social dynamics. OBJECTIVE: The aim of this study was to investigate the association between nighttime population volumes, the COVID-19 epidemic, and the implementation of public health and social measures in Tokyo. METHODS: We used mobile phone location data to estimate populations between 10 PM and midnight in seven Tokyo metropolitan areas. Mobile phone trajectories were used to distinguish and extract on-site dining from stay-at-work and stay-at-home behaviors. Numbers of new cases and symptom onsets were obtained. Weekly mobility and infection data from March 1 to November 14, 2020, were analyzed using a vector autoregression model. RESULTS: An increase in the number of symptom onsets was observed 1 week after the nighttime population volume increased (coefficient=0.60, 95% CI 0.28 to 0.92). The effective reproduction number significantly increased 3 weeks after the nighttime population volume increased (coefficient=1.30, 95% CI 0.72 to 1.89). The nighttime population volume increased significantly following reports of decreasing numbers of confirmed cases (coefficient=-0.44, 95% CI -0.73 to -0.15). Implementation of social measures to restaurants and bars was not significantly associated with nighttime population volume (coefficient=0.004, 95% CI -0.07 to 0.08). CONCLUSIONS: The nighttime population started to increase after decreasing incidence of COVID-19 was announced. Considering time lags between infection and behavior changes, social measures should be planned in advance of the surge of an epidemic, sufficiently informed by mobility data.

Comparison of touch-up ablation rate and pulmonary vein isolation durability between hot balloon and cryoballoon.

INTRODUCTION: This study aimed to compare touch-up ablation (TUA) rates and pulmonary vein isolation (PVI) durability of hot balloon ablation (HBA) and cryoballoon ablation (CBA) in paroxysmal atrial fibrillation (PAF) patients. METHODS: In total, 137 PAF patients were enrolled in the study. Among them, 59 underwent two HBA procedures at 6-month intervals and 78 patients underwent two CBA sessions, both regardless of atrial fibrillation recurrence. Propensity score matching was performed to estimate similar patient characteristics between the HBA and CBA groups. RESULTS: Each group comprised of 46 matched patients for comparison. The TUA rate at the first session was higher for HBA (49 of 184 PVs) than for CBA (20 PVs) (P = .01), with the highest incidence at the left superior pulmonary vein (LSPV). The rates of PVI durability at the second session performed 7 months later were similar between HBA (168 of 184 PVs) and CBA (162 PVs) groups. The PVI durability rate at the TUA sites of the first session was higher for HBA than for CBA (41 of 49 PVs vs 10 PVs, respectively; P = .01). Fifty percent of the patients underwent HBA at 73°C for the LSPV. HBA performed at 73°C yielded a lower TUA rate than that at 70°C (16 of 23 PVs vs 7 of 23 PVs; P = .008). CONCLUSIONS: While PVI durability was similar between HBA and CBA, the TUA rate was higher for HBA than for CBA, especially on the LSPV. For LSPV, HBA at a balloon temperature of 73°C may reduce the TUA rate.

Recurrent ischemic stroke in patients with atrial fibrillation ablation and prior stroke: A study based on etiological classification.

BACKGROUND: Different subtypes of ischemic stroke may have different risk factors, clinical features, and prognoses. This study investigated the incidence and mode of stroke recurrence in patients with a history of stroke who underwent atrial fibrillation (AF) ablation. METHODS: Of 825 patients who underwent AF ablation from 2006 to 2016, 77 patients (9.3%, median age 69 years) with a prior ischemic stroke were identified. Patients were classified as those with prior cardioembolic (CE) stroke (n = 55) and those with prior non-CE stroke (n = 22). The incidence and pattern of stroke recurrence were investigated. RESULTS: The incidence of asymptomatic AF (54.5% vs 22.7%; P = .011) and left atrial volume (135.8 mL vs 109.3 mL; P = .024) was greater in the CE group than in the non-CE group. Anticoagulation treatment was discontinued at an average of 28.1 months following the initial ablation in 34 (44.2%) patients. None of the patients developed CE stroke during a median 4.1-year follow-up. In the non-CE group, 2 patients experienced recurrent non-CE stroke (lacunar infarction in 1 and atherosclerotic stroke in 1); however, AF was not observed at the onset of recurrent ischemic stroke. CONCLUSIONS: In patients with a history of stroke who underwent catheter ablation for AF, the incidence of recurrent stroke was 0.54/100 patient-years. The previous stroke in these patients may not have been due to AF in some cases; therefore, a large-scale prospective study is warranted to identify the appro priate antithrombotic therapy for the prevention of potentially recurrent stroke.

Catheter ablation for monomorphic ventricular tachycardia in Brugada syndrome patients: detailed characteristics and long-term follow-up.

PURPOSE: Brugada syndrome (BrS) is a risk of sudden cardiac death due to polymorphic ventricular tachycardia and ventricular fibrillation with unusual monomorphic ventricular tachycardia (MVT). Detailed characteristics of MVT and long-term outcome of catheter ablation are still unknown. This study is aimed to identify the detailed characteristics and long-term follow-up of catheter ablation in BrS patients. METHODS: We evaluated 188 patients who were diagnosed with BrS from March 1999 to March 2018. Of those, patients who developed MVT and underwent catheter ablation were included. We identified eight MVTs in seven BrS patients. RESULTS: Three of them already had implantable cardioverter-defibrillator, and MVTs were terminated by cardioversion or anti-tachycardia pacing. Four patients presented with MVT originating from the right ventricular outflow tract, one patient had MVT arising from the LV septum, one patient had MVT arising from the tricuspid annulus, and one patient had bundle branch reentry ventricular tachycardia. All MVTs were successfully treated by catheter ablation in the acute phase, and seven of eight (87.5%) were free from ventricular tachyarrhythmia during the long-term follow-up (median, 7.2 years). CONCLUSIONS: All MVT cases were successfully treated by catheter ablation. We observed high ventricular arrhythmia free rate following catheter ablation during the long-term follow-up period. BrS patients who developed MVT should consider catheter ablation.

Multiple peritricuspidal reentry tachycardias after cardiac infiltration by leukaemia: a case report.

BACKGROUND: Cardiac involvement by malignant lymphocytic neoplasms is a rare phenomenon. Little is known concerning cardiotoxicity in the chronic phase after completion of treatment. CASE SUMMARY: A 50-year-old woman with a past history of cardiac involvement of acute lymphoblastic leukaemia (ALL) underwent electrophysiologic study and catheter ablation for symptomatic atrial tachycardia (AT). She was diagnosed with ALL when she was 8 years old and treated with systematic chemotherapy with prednisolone and vincristine. After complete remission, she suffered from repeated palpitations beginning at the age of 16 years. Electrophysiologic study using high-density (HD) mapping showed two types of peritricuspid AT in addition to low voltage in the right atrium with conduction delay. DISCUSSION: Cardiac involvement by malignant lymphocytic neoplasms is a rare phenomenon, and cardiac infiltration often disappears after remission of ALL. Thus, little is known about cardiac electrophysiological characteristics in the chronic phase of complete remission of ALL. We describe a rare case of a patient with multiple peritricuspidal reentry tachycardias after cardiac infiltration by leukaemia using a HD mapping system.

Characteristics of Marshall bundle-related atrial tachycardias using an ultrahigh-resolution mapping system.

PURPOSE: Marshall bundle (MB)-related atrial tachycardias (ATs) have already been described; however, their characteristics using an ultrahigh-resolution mapping system are not yet well known. The purpose of this study was to clarify the characteristics of MB-related ATs with ultrahigh-resolution mapping. METHODS: In 28 patients who underwent an electrophysiological study for ATs using an ultrahigh-resolution mapping system, precise circuits of 37 ATs were detected. Among those ATs, five were diagnosed as MB-related ATs that had epicardial connections among the reentrant circuits (mean age 76.6 ± 3.7 years, one male patient). We analyzed the characteristics of those MB-related ATs with ultrahigh-resolution mapping. RESULTS: The mean cycle length was 260 ± 60 ms, and the total acquired electrograms were 12,962 ± 2616 points. Two ATs were perimitral ATs, two rotated around the left pulmonary vein (PV), and one rotated around the left inferior PV. All ATs had a centrifugal activation pattern: 5 o'clock on the mitral annulus in four ATs and the upper ridge in one. Tiny potentials, which indicated epicardial potentials covering the cycle length, were detected in four of five ATs. The local activation times covered over 95% of the tachycardia cycle length on the endocardial side only in all ATs. All ATs were terminated during a radiofrequency ablation from the endocardial side of the Marshall bundle. CONCLUSIONS: The ultrahigh-resolution mapping system demonstrated an activation map of MB-related ATs with a centrifugal pattern. Macroreentrant tachycardias with a centrifugal activation pattern should be considered as possible MB-related ATs.

Characteristics of ventricular intracardiac electrograms of ventricular tachycardias originating from the epicardia in patients with an implantable cardioverter defibrillator.

INTRODUCTION: While characteristic waveforms of 12-lead electrocardiograms have been reported to predict the epicardial origin of ventricular tachycardia (VT), it has not been fully examined whether ventricular intracardiac electrograms (VEGMs) recorded from the implantable cardioverter defibrillator (ICD) via telemetry can determine the origin of VT or not. The aim of this study was to investigate the VEGM characteristics of VT originating from the epicardia. METHOD AND RESULTS: Intracardiac VEGMs of the induced VTs, with detected sites of origin during the VT study, were recorded in 15 (23 VTs) of the 46 patients. The characteristics of the 23 VTs were evaluated using far-field and near-field VEGMs recorded via telemetry. Five of 23 VTs were found to be focused on the epicardial site (epi group) and 18 VTs were focused on the endocardium (endo group). VTs of the epi group had longer VEGM duration in far-field EGM than those of the endo group (epi group: 240 ± 49 ms vs endo group: 153 ± 45 ms; P = 0.002) and the duration from the onset to the peak of VEGM was also longer than that of the endo group (epi group: 153 ± 53 ms vs endo group: 63 ± 28 ms; P < 0.001). There was no difference in the V wave duration in tip-ring EGM between both groups (epi group: 122 ± 52 ms vs endo group: 98 ± 6 ms; P = 0.377). CONCLUSION: Evaluation of intracardiac VEGM before VT ablation may be helpful to predict the epicardial origin of VT in patients with an ICD.

Macroreentrant atrial tachycardia detouring the epicardium at the anterior wall of the left atrium.

A 79-year-old woman with a history of pulmonary vein isolation for persistent atrial fibrillation was admitted for recurrence of atrial tachycardia, with a tachycardia cycle length of 236 milliseconds. The ultra-high-resolution mapping system revealed that tachycardia circuit detouring the epicardium at the anterior wall scar and breaking through to the endocardium below the left atrial appendage. Radiofrequency energy was applied to this site, which successfully terminated the tachycardia. This case suggests that epicardial conduction could occur even at the left atrial anterior wall and identifies a variation in epicardial conduction around the left atrium, which could be a tachycardia circuit.

The relationship between obstructive sleep apnea and recurrence of atrial fibrillation after pulmonary vein isolation using a contact force-sensing catheter.

PURPOSE: Our aim was to elucidate the relationship between obstructive sleep apnea (OSA) and atrial fibrillation (AF) recurrence after repeated pulmonary vein isolation (PVI). METHODS: We conducted a non-randomized observational study, with the data prospectively collected. One hundred patients (paroxysmal AF, n = 89) underwent PVI using a contact force-sensing catheter. All patients underwent an electrophysiological study and additional ablation for left atrium-pulmonary vein (PV) reconnection and non-PV foci, 6 months after the first treatment session, regardless of AF recurrence. Those with an apnea-hypopnea index ≥ 15 were diagnosed with OSA. Continuous positive air pressure (CPAP) therapy was initiated after the second treatment session, based on results of a sleep study. For analysis, patients were classified into the non-OSA (n = 66), treated OSA (OSA patients undergoing CPAP; n = 11), and untreated OSA (n = 23) groups, and between-group differences evaluated. RESULTS: After the first session, AF recurrence was observed in 18.2% (12/66) and 14.7% (5/34) of patients without and with OSA, respectively (P = 0.678). After the second procedure, the rate of AF recurrence was 12.1% (8/66) in the non-OSA group, 9.1% (1/11) in the treated OSA group, and 8.7% (2/23) in the untreated OSA group (log-rank P = 0.944). CONCLUSIONS: The rate of AF recurrence might not be greater in patients with untreated OSA than in those without OSA and those with treated OSA after repeated PVI, using a contact force-sensing catheter, for patients with paroxysmal or short-term persistent AF.

High-resolution 3D mapping of epicardial conduction during Marshall bundle-related atrial tachycardia.

A 73-year-old woman was admitted for atrial tachycardia (AT) ablation. The activation map and pacing study indicated that the AT propagated around the left pulmonary vein and that the Marshall bundle (MB) bypassed the scar area of the left pulmonary vein ridge and mitral isthmus. The Rhythmia Mapping System revealed double potentials propagated along the assumed position of the MB. The mapping system includes a confidence mask that can be used to visually identify low-confidence areas of the map based upon extremely low-voltage signals. Given the low-voltage area in the endocardial side, the epicardial conduction was emphasized.

Ventricular tachycardia storm originating from interventricular septum successfully treated with surgical cryoablation with electroanatomic and electrophysiological mapping before dual valve replacement.

A 58-year-old man with dilated cardiomyopathy was admitted with heart failure. He had a history of two catheter ablation procedures for ventricular tachycardia (VT) originating from the intraventricular septum (IVS). Before dual valve replacement (DVR), he suffered a VT storm. An electrophysiological study revealed an extended low-voltage area at the IVS with the exit of the induced VT at the anterior side. Radiofrequency application was performed at the VT exit as a landmark for surgical cryoablation (SA). During the DVR, SA was performed at the IVS using this landmark. After SA, the patient had no ventricular tachyarrhythmia.

Successful catheter ablation of ventricular premature complexes from the right atrial side of the atrioventricular septum with good contact force.

The acquisition of good contact force for radiofrequency catheter ablation of ventricular premature complexes (VPCs) originating from the basal septum of the left ventricle (LV) is often difficult. We describe a case of VPCs originating from the basal septum of the LV, which were successfully eliminated by applying radiofrequency at the right atrium (RA) side of the atrioventricular septum (AVS) without causing any significant impairment of atrioventricular conduction because the ablation catheter could obtain better contact force through the RA approach. Moreover, intracardiac echocardiography (ICE) and RA angiography effectively demonstrated the AVS.