Catheter contact angle influences local impedance drop during radiofrequency catheter ablation: Insight from a porcine experimental study with 2 different LI-sensing catheters.

BACKGROUND: Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with two different LI-sensing catheters in a porcine experimental study. METHODS: Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 W and a duration of 30 s. The contact force (CF) (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n = 8 each). The LI rise, LI drop, and lesion size were evaluated. RESULTS: The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths. CONCLUSION: The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT.

Reduced atrial conduction velocity is associated with the recurrence of atrial fibrillation after catheter ablation.

The recurrence of atrial fibrillation (AF) after catheter ablation (CA) is still an unsolved issue. Although structural remodeling is relatively well defined, the method to assess electrical remodeling of the atrium is not well established. In this study, we evaluated the relationship between atrial conduction properties and recurrence after CA for AF. One hundred six consecutive patients (66 ± 11 years old, male: 68%) who underwent CA for AF with a CARTO system from July 2016 to July 2019 were enrolled in this study. An activation map of both atria was constructed to precisely evaluate the total conduction time, distance, and conduction velocity between the earliest and latest activation sites during sinus rhythm. All parameters were compared between the patients with or without AF recurrence. Of the patients, 27 had an AF recurrence (Rec group). The left atrial (LA) conduction velocity was significantly slower in the Rec group than in the non-Rec group (101.2 ± 17.9 vs. 116.9 ± 18.0 cm/s, P < 0.01). Likewise, the right atrial (RA) conduction velocity was significantly slower in the Rec group than in the non-Rec group (81.1 ± 17.5 vs. 103.6 ± 25.4 cm/s, P < 0.01). A multivariate logistic analysis demonstrated that the LA and RA conduction velocities were independent predictors of AF recurrence, with adjusted odds ratios of 0.95 (95% confidential interval: 0.91-0.98, P < 0.01) and 0.94 (0.89-0.98, P < 0.01), respectively. In conclusion, slower conduction velocity of the atrium was associated with AF recurrence after pulmonary vein isolation.

Development of KOSEN Weather Station and Provision of Weather Information to Farmers.

In recent years, environmental information monitoring in the agricultural field has become an important issue. There is an increasing demand for meteorological information in local areas such as a rice field, a greenhouse, etc., owned by an agricultural worker. Conventional research has been actively conducted on weather stations in local areas. However, weather stations that are inexpensive, highly accurate, and have achieved stable measurements indoors and outdoors for long periods of time (over a year) are not reported. In addition, there is a lack of research that simultaneously acquires weather information, stores weather information, and provides weather information to farmers. These three functions are important in the agricultural field. In this paper, we discuss the development of a meteorological observation device, the construction of a cloud server for storing meteorological information, and the provision of information to users. First, we develop the novel meteorological observation device (KOSEN-Weather Station), which applies a simple Aßmann's aspiration psychrometer for highly accurate temperature and humidity measurements. To evaluate the reliability of KOSEN-WS, we compare the weather information measured by KOSEN-WS with that of WXT520. As a result, it is shown that KOSEN-WS is viable. Then, KOSEN-WS is installed in the field, and the stability and durability of KOSEN-WS are examined. As a result, the KOSEN-WS has been operating stably over 19 months and provides weather information to users. Then, it is shown that the KOSEN-WS is able to operate continuously under the environment of -16.5 °C to 44.9 °C. Next, for the storage of meteorological information, we construct the cloud server. Then, a webpage is created to provide easy-to-understand weather information to farmers. Furthermore, to prevent damage to crops, if the current temperature is lower than the set temperature, or if the current temperature is higher than the set temperature, an alert is sent to the farmers. As a result, the system is highly evaluated by agricultural workers and JA staff. From the above results, the effectiveness of this system is shown.

Ruptured Abdominal Aortic Aneurysm Repair Using Open Proximal Anastomosis Under Deep Hypothermic Circulatory Arrest.

Proximal aortic clamping under normothermia is generally adequate for operative repair of abdominal aortic rupture; however, the hypothermic circulatory arrest (HCA) technique is not as common. Proximal exposure and clamping are sometimes difficult due to the risk of bleeding, rerupture, and ischemia. We present a successful case of a ruptured abdominal aortic aneurysm (AAA) that was repaired using cardiopulmonary bypass with HCA. A 75-year-old man presented with sudden back pain and was diagnosed with a ruptured AAA using computed tomography. The aneurysm had a maximal diameter of 100 mm and protruded anteriorly just below the renal arteries. The rupture site was close to the renal arteries, and thus, there was a high risk of bleeding and shock during proximal exposure. Cardiopulmonary bypass was established by cannulation of the right axillary artery and right femoral vein, following which open laparotomy was performed. Proximal exposure and anastomosis could be safely performed using HCA. This cardiopulmonary bypass with HCA technique may be useful as a surgical strategy for ruptured juxta-renal AAAs.

Interhospital transportation of a COVID-19 patient undergoing veno-venous extracorporeal membrane oxygenation by helicopter.

Some coronavirus disease 2019 (COVID-19) patients develop rapidly progressive acute respiratory distress syndrome and require veno-venous extracorporeal membrane oxygenation (V-V ECMO). A previous study recommended the transfer of ECMO patients to ECMO centers. However, because of the pandemic, a limited number of ECMO centers are available for patient transfer. The safe long-distance interhospital transport of these patients is a concern. To minimize transportation time, helicopter use is a suitable choice. We report the first case of a COVID-19 patient on V-V ECMO, transferred to our ECMO center by helicopter. A 45-year-old man with rheumatoid arthritis history, treated with immunosuppressants, presented with fever and sore throat. He was diagnosed with COVID-19 following a positive severe acute respiratory syndrome coronavirus 2 polymerase chain reaction test result and was subsequently prescribed favipiravir. However, his respiratory failure progressively worsened. On day 10 of hospitalization at the previous hospital, he was intubated, and we received a request for ECMO transport on the next day. The ECMO team, who wore personal protective equipment (N95 respirators, gloves, gowns, and face shields), initiated V-V ECMO in the referring hospital and safely transported the patient by helicopter. The flight time was 7 min. He was admitted to the intensive care unit of our hospital and received tocilizumab. He was discharged on hospital day 31 with no significant sequelae. In this case report, we discuss important factors for the safe and appropriate interhospital transportation of COVID-19 patients on ECMO as well as staff and patient safety during helicopter transportation.

[Valve Re-replacement after Aortic Valve Replacement with Starr-Edwards Ball Valve Forty-five Years Ago:Report of a Case].

The patient was a 67-year-old man. At 22 years of age, he underwent aortic valve replacement with Starr-Edwards ball valve. At 67 years of age, he complained of fatigue of the New York Heart Association (NYHA) class Ⅲ condition. He was diagnosed with mitral regurgitation, tricuspid regurgitation, ascending aortic aneurysm and chronic atrial fibrillation. Transthoracic and transesophageal echocardiograms showed a mobile, elongated echogenic mass attached to the valve cage and floating downstream. We performed Bentall procedure, ascending aortic replacement, mitral valve replacement, tricuspid annuloplasty and left atrial appendage closure. Explanted ball valve showed extensive cloth destruction and partial cloth tear. Mild pannus formation was observed beneath the valve. Despite 45 years after initial operation, significant valve dysfunction was not observed.

Photocatalysis of a Dinuclear Ru(II)-Re(I) Complex for CO2 Reduction on a Solid Surface.

The development of CO2-reduction photocatalysts is one of the main targets in the field of artificial photosynthesis. Recently, numerous hybrid systems in which supramolecular photocatalysts comprised of a photosensitizer and catalytic-metal-complex units are immobilized on inorganic solid materials, such as semiconductors or mesoporous organosilica, have been reported as CO2-reduction photocatalysts for various functions, including water oxidation and light harvesting. In the present study, we investigated the photocatalytic properties of supramolecular photocatalysts comprised of a Ru(II)-complex photosensitizer and a Re(I)-complex catalyst fixed on the surface of insulating Al2O3 particles: the distance among the supramolecular photocatalyst molecules should be fixed. Visible-light irradiation of the photocatalyst in the presence of an electron donor under a CO2 atmosphere produced CO selectively. Although CO formation was also observed for a 1:1 mixture of mononuclear Ru(II) and Re(I) complexes attached to an Al2O3 surface, the photocatalytic activity was much lower. The activity of the Al2O3-supported photocatalyst was strongly dependent on the adsorption density of the supramolecular moiety, where the initial rate of photocatalytic CO formation was faster at lower density and higher photocatalyst durability was achieved at higher density. One of the main reasons for the former phenomenon is the decreased quenching fraction of the excited state of the photosensitizer unit by the reductant dissolved in the solution phase in the case of higher density. This is due to the self-quenching of the excited photosensitizer unit and steric hindrance between the condensed supramolecular photocatalyst molecules attached to the surface. The higher durability of the more condensed system is caused by intermolecular electron transfer between reduced supramolecular photocatalyst molecules, which accelerates the formation of CO in the photocatalytic CO2 reduction. Coadsorption of a Ru(II) mononuclear complex as a redox photosensitizer could drastically reinforce the photocatalysis of the supramolecular photocatalyst on the surface of the Al2O3 particles: more than 10 times higher turnover number and about 3.4 times higher turnover frequency of CO formation. These investigations provide new architectures for the construction of efficient and durable hybrid photocatalytic systems for CO2 reduction, which are composed of metal-complex photocatalysts and solid materials.

Precise Signals with a High-Density Grid Mapping Catheter Are Useful for an Entrainment Study.

Complex atrial tachycardias (ATs) after catheter ablation or a MAZE procedure is sometimes difficult to determine the circuits of the tachycardia. A high-density, grid-shapes mapping catheter has been launched, which can be useful for detecting the detail circuits of tachycardias on three-dimensional mapping systems. The signal quality is also important for performing electrophysiological studies (EPSs), such as entrainment mapping, to identify the circuit. This unique mapping catheter has 1 mm electrodes on 2.5 Fr shafts, which improve the signal quality. The high-quality intracardiac electrograms facilitate differentiating small critical potentials, which allows us to perform detailed entrainment mapping in targeted narrow areas. Here, we describe a patient with a perimetral AT with epi-endocardium breakthrough after a MAZE surgery and catheter ablation, which was treated successfully along with detailed entrainment mapping using the HD Grid. This catheter with high-quality signals could be a significant diagnostic tool for a classic EPS as well as for the construction of 3D mapping.

Prediction of Lethal Arrhythmic Events Through Remote Monitoring Using Heart Rate Variability Analysis in Patients with an Implantable Cardioverter Defibrillator.

We prospectively collected device and heart rate data through remote monitoring (RM) of patients with an implantable cardioverter defibrillator (ICD). The objective was to identify the predictors of lethal arrhythmic events (VT/VF).Thirty-three patients (mean age: 50 years) with ICDs [with functionality of heart rate variability (HRV) analysis] were divided into two groups [VT/VF (+), VT/VF (-) ]. Clinical, device (ventricular lead impedance; amplitude of ventricular electrogram), and HRV data were compared between the two groups. The NN interval-index (SDNNi) was calculated for every 5 minutes, and the mean, maximum, minimum, and standard deviation of SDNNi during the 24-hour period were used.During the observation period of 13 ± 10 months, 10 patients experienced VT/VF events. Total mean, max, and min SDNNi were higher in the VT/VF (+) than the VT/VF (-) group (132.9 ± 9.3 versus 93.5 ± 6.1, P = 0.0013; 214.6 ± 10.6 versus 167.0 ± 7.0, P = 0.0007; 71.2 ± 7.5 versus 43.9 ± 4.9, P = 0.0047). On logistic regression analysis, a total mean SDNNi of 100.1, max SDNNi of 185.0 and min SDNNi of 52.0 as cut-off values for prediction of a VT/VF event demonstrated significant receiver operating characteristic (ROC) curves (AUC = 0.86, P = 0.0007; AUC = 0.84, P = 0.0005; AUC = 0.78, P = 0.0030). The max ΔSDNNi, i.e., difference from baseline SDNNi, and min ΔSDNNi in 7 and 28 days preceding VT/VF events were significant predictors of VT/VF events.Time-domain HRV analysis through a RM system may help identify patients at high risk of lethal arrhythmic events; in addition, it may help predict the occurrence of lethal arrhythmic events in specific cases.

Kinetics and Mechanism of Intramolecular Electron Transfer in Ru(II)-Re(I) Supramolecular CO2-Reduction Photocatalysts: Effects of Bridging Ligands.

The supramolecular photocatalysts in which a Ru(II) complex as a molecular redox photosensitizer unit and a Re(I) complex as a molecular catalyst unit are connected with a various alkyl or ether chain have attracted attention because they can efficiently photocatalyze CO2 reduction with high durability and high selectivity of CO formation, especially on various solid materials such as semiconductor electrodes and mesoporous organosilica. The intramolecular electron transfer from the one-electron reduced photosensitizer unit to the catalyst unit, which follows excitation of the photosensitizer unit and subsequent reductive quenching of the excited photosensitizer unit by a reductant, is one of the most important processes in the photocatalytic reduction of CO2. We succeeded in determining the rate constants of this intramolecular electron transfer process by using subnanosecond time-resolved IR spectroscopy. The logarithm of rate constants shows a linear relationship with the lengths of the bridging chain in the supramolecular photocatalysts with one bridging alkyl or ether chain. In conformity with the exponential decay of the wave function and the coupling element in the long-distance electron transfer, the apparent decay coefficient factor (ß) in the supramolecular photocatalysts with one bridging chain was determined to be 0.74 Å-1. In the supramolecular photocatalyst with two ethylene chains connecting between the photosensitizer and catalyst units, on the other hand, the intramolecular electron transfer rate is much faster than that with only one ethylene chain. These results strongly indicate that the intramolecular electron transfer from the one-electron reduced species of the Ru photosensitizer unit to the Re catalyst unit proceeds by the through-bond mechanism.

Metallonanobelt: A Kinetically Stable Shape-Persistent Molecular Belt Prepared by Reversible Self-Assembly Processes.

A triptycene-based shape-persistent belt-shaped macrocycle, metallonanobelt, was synthesized by the self-assembly of 2,3,6,7-tetraaminotriptycene L and square planar Pd2+. The pentamer was selectively formed by the complexation of L with Pd2+ in the presence of the pillar[6]arene derivative P6 having triethylene glycol pendant as a template, whereas a mixture of a trimer, tetramer, and pentamer was obtained in the absence of the template. The pentamer was successfully isolated based on the solubility difference between the metallonanobelt and the template. It was also revealed that the isolated pentamer was remarkably stable in solutions such as acetonitrile or methanol thanks to the relatively inert planar chelate metal complex, [Pd( o-phenylenediamine)2] unit. Thus, we can handle the metallonanobelt almost as a static organic nanobelt that is synthesized covalently.

[Aorta-left Main Trunk Interposition for Adult Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery Using a Prosthetic Graft;Report of a Case].

A 70-year-old woman with back pain was diagnosed with adult anomalous origin of the left coronary artery from the pulmonary artery [Bland-White-Garland (BWG) syndrome]. Preoperative transthoracic echocardiography showed diffuse hypokinesia of the left ventricle and mild mitral valve regurgitation. Coronary angiography revealed dilatation of both coronary arteries, but no aneurysms. The left coronary ostium was removed as buttons of the pulmonary arterial wall, and a prosthetic graft (8 mm ePTFE graft) was interposed between the ascending aorta and coronary button. The pulmonary arterial wall was repaired with a bovine pericardium. Postoperative angiography showed good flow of the graft. The antegrade flow provided by this simple technique will allow feasible percutaneous coronary intervention in the future.

Usability evaluation of a glove-type wearable device for efficient biometric collection during triage.

To efficiently allocate medical resources at disaster sites, medical workers perform triage to prioritize medical treatments based on the severity of the wounded or sick. In such instances, evaluators often assess the severity status of the wounded or sick quickly, but their measurements are qualitative and rely on experience. Therefore, we developed a wearable device called Medic Hand in this study to extend the functionality of a medical worker's hand so as to measure multiple biometric indicators simultaneously without increasing the number of medical devices to be carried. Medic Hand was developed to quantitatively and efficiently evaluate "perfusion" during triage. Speed is essential during triage at disaster sites, where time and effort are often spared to attach medical devices to patients, so the use of Medic Hand as a biometric measurement device is more efficient for collecting biometric information. For Medic Hand to be handy during disasters, it is essential to understand and improve upon factors that facilitate its public acceptance. To this end, this paper reports on the usability evaluation of Medic Hand through a questionnaire survey of nonmedical workers.

"Honey pot"-like lesion formation: Impact of catheter contact angle on lesion formation by novel diamond-embedded temperature-controlled ablation catheter in a porcine experimental model.

BACKGROUND: Novel diamond-embedded catheter enables precise temperature-controlled ablation. However, the effects of contact angle on lesion formation of this catheter are poorly understood. OBJECTIVE: The purpose of this study was to evaluate lesion formation using the temperature-controlled ablation catheter embedded with diamond at different angles in a porcine experimental model. METHODS: Freshly sacrificed porcine hearts were used. Radiofrequency catheter ablation was performed at 50 W for 15 seconds at an upper temperature setting of 60°C. The contact force (5g, 10g, 30g) and catheter contact angles (30°, 45°, 90°) were changed in each set (n = 13 each). Surface width, maximum lesion width, lesion depth, surface area, distance from the distal edge to the widest area, and impedance drop were evaluated. RESULTS: Surface width and maximum lesion width were longer at 30° than at 90° (P <.05). There were no significant differences in the lesion depth by catheter angle except at 30g. Surface area was larger at 30° than at 90° (P <.05). Distance from the distal edge to the widest area was longer at 30° than at 90° (P <.05). There were no significant differences in impedance drop according to catheter angle. CONCLUSION: With diamond-embedded temperature-controlled ablation catheters, lesion width increased at a shallower contact angle, whereas lesion depth did not. Surface area also increased at a shallower contact angle. This catheter created a large ablation lesion on the proximal side of the catheter, which looked like a "honey pot."

Cut-Off Value of Capillary Refill Time for Peripheral Circulatory Failure Diagnosis.

INTRODUCTION: Capillary refill time (CRT) is an indicator of peripheral circulation and is recommended in the 2021 guidelines for treating and managing sepsis. STUDY OBJECTIVE: This study developed a portable device to realize objective CRT measurement. Assuming that peripheral blood flow obstruction by the artery occlusion test (AOT) or venous occlusion test (VOT) increases the CRT, the cut-off value for peripheral circulatory failure was studied by performing a comparative analysis with CRT with no occlusion test (No OT). METHODS: Fourteen (14) healthy adults (age: 20-26 years) participated in the study. For the vascular occlusion test, a sphygmomanometer was placed on the left upper arm of the participant in the supine position, and a pressure of 30mmHg higher than the systolic pressure was applied for AOT, a pressure of 60mmHg was applied for VOT, respectively, and no pressure was applied for No OT. The CRT was measured from the index finger of the participant's left hand. RESULTS: Experimental results revealed that CRT was significantly longer in the AOT and did not differ significantly in the VOT. The cut-off value for peripheral circulatory failure was found to be 2.88 seconds based on Youden's index by using receiver operating characteristic (ROC) analysis with AOT as positive and No OT as negative. CONCLUSION: Significant results were obtained in a previous study on the evaluation of septic shock patients when CRT > three seconds was considered abnormal, and the cut-off value for peripheral circulatory failure in the current study validated this.

Epidemiology of sepsis in a Japanese administrative database.

Sepsis is the leading cause of death worldwide. Considering regional variations in the characteristics of patients with sepsis, a better understanding of the epidemiology in Japan will lead to further development of strategies for the prevention and treatment of sepsis. To investigate the epidemiology of sepsis, we conducted a systematic literature review of PubMed between 2003 and January 2023. Among the 78 studies using a Japanese administrative database, we included 20 that defined patients with sepsis as those with an infection and organ dysfunction. The mortality rate in patients with sepsis has decreased since 2010, reaching 18% in 2017. However, the proportion of inpatients with sepsis is increasing. A study comparing short-course (≤7 days) and long-course (≥8 days) antibiotic administration showed lower 28-day mortality in the short-course group. Six studies on the treatment of patients with septic shock reported that low-dose corticosteroids or polymyxin B hemoperfusion reduced mortality, whereas intravenous immunoglobulins had no such effect. Four studies investigating the effects of treatment in patients with sepsis-associated disseminated intravascular coagulation demonstrated that antithrombin may reduce mortality, whereas recombinant human soluble thrombomodulin does not. A descriptive study of medical costs for patients with sepsis showed that the effective cost per survivor decreased over an 8-year period from 2010 to 2017. Sepsis has a significant impact on public health, and is attracting attention as an ongoing issue. Further research to determine more appropriate prevention methods and treatment for sepsis should be a matter of priority.

Lesion size index-guided cavotricuspid isthmus linear ablation.

BACKGROUND: The lesion size index (LSI) predicts radiofrequency (RF) ablation lesion size and is an established parameter for pulmonary vein isolation. However, the effectiveness and safety of LSI for cavotricuspid isthmus (CTI) linear ablation remain unclear. METHODS: This single-center retrospective study included 50 of patients (67 ± 10 years, 68% male) who underwent de novo CTI linear ablation between July 2020 and December 2020. The LSI target was set at 5.0 and 4.0 for the anterior 2/3 and posterior 1/3 segments, respectively. Acute procedural parameters of ablation were evaluated. RESULTS: Acute bidirectional CTI block was achieved in all patients with an RF application time of 4.0 min (3.1-5.0 min), RF application number of 15 ± 7, and length of CTI of 36.9 ± 9.3 mm. First-pass bidirectional conduction block of the CTI was achieved in 39/50 (78%) patients. No major complications were observed. The contact force (CF) per application was significantly lower in the gap tag group than in the non-gap tag group (7 g [7-8 g] vs. 10 g [7-12 g], P = 0.0284). CONCLUSIONS: LSI-guided CTI linear ablation is an effective and safe treatment approach. CF affects gap formation, even when the target LSI is the same.