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To improve motion accuracy through functional electrical stimulation (FES) of forearm muscles, feedback control laws are applied to the index finger’s metacarpophalangeal (MP) joint. This paper introduces a proxy-based super-twisting algorithm (PSTA) for precise servo control of MP joints via FES. The PSTA combines first-order sliding mode control with a second-order super-twisting algorithm, effectively preventing windup during FES saturation and ensuring robust, accurate control. An implicit Euler method minimizes numerical chattering in the digital implementation. Experiments with Arduino and volunteers confirm the algorithm’s effectiveness.

In order to find effective movements on an office chair for preventing back pain, the paper measures EMG (electromyogram) signal and evaluates cognitive test. Core muscles of subjects on a balance ball are measured when there are forced movement and voluntary movement of the ball. The measurements show the forced movement and discontinuity movement on the ball is more effective in the meaning of muscle activity. The paper also studies the effect of movement with the balance ball on the efficiency of office workers. This is because, even if the movement is good for preventing back pain, it is not desirable to reduce work efficiency. Two cognitive tests, addition test and flanker test, are used to investigate the efficiency of office workers when the movements with the balance ball and no movements with normal chair in the view points of work reduction rate and correct answer rate. The results show the efficiency of office workers is almost the same as the case of movements with the balance ball and no movements with normal chair. Totally the study shows effective movements on the balance ball which activate the core muscle activity efficiently. It also shows the movement does not reduce the office work efficiency.

This paper proposes a swash plate disturbance application device for human standing stability evaluation. It is known that when a mechanical disturbance is applied to the lower body, the COP (center of pressure) trajectory of the human is closely related to the standing stability of the human. Based on this fact, the paper first proposes a swash plate disturbance application device to measure the COP trajectory when the mechanical disturbance is applied. A linear identification method, where the input is the disturbance and the output is COP trajectory, is used to get a human standing stability system model. The model is expressed by a transfer function which includes the parameters of poles and zeros. Using the identified parameters, a human standing stability index is proposed. By some swash plate disturbance experiments for human standing and system identification experiments under several experimental conditions based on the proposed method, parameters of stability system dynamical model are obtained. The proposed index is calculated using the parameters. Then, it is found that the stability index values according to the experimental conditions such as normal standing and tandem standing, which is known more unstable one and less stable one, are properly obtained.

A generic control method is proposed for the non-square systems where the number of system inputs is not equal to that of the states. The non-square system to be controlled is first restructured in form of the combination of a square system and the variation from the original non-square system. This variation term is treated as a time-varying uncertainty to the restructured square system. Thus the stabilization for a non-square system is reformulated as an adaptive control problem for a square system. In this paper we address this adaptive control problem by applying the function approximation technique. Specifically, we can parameterize the variation with a chosen basis function weighted by unknown constant parameters. Then we define an update law such that the parameters of the weighted basis function can be automatically determined and the variation between the auxiliary square system and the original non-square system can then be eliminated. The asymptotic stability is established for the closed loop system formulated by the non-square system and the constructed controller. The feasibility of the proposed control method is verified under simulations for linear system, nonlinear underactuated system, and nonholonomic system.

Metabolic cost during walking is positively linked to exercise intensity. For a walking assistive device, one of the major aims should be the maximization of wearers’ metabolic benefits for different walking situations. Toward this goal, this paper experimentally evaluates the influence of an authors’ soft robotic suit, which has been developed to assist hip flexion for energy-efficient walking of elderly persons in daily life activities, on metabolic cost reduction in the long-distance level and inclined walking. Experiment results show that, for a 79-year-old healthy male subject, the robotic suit significantly reduced metabolic cost in the condition of the robotic suit worn and powered on compared with the condition of worn but powered off.

As a walking assistive device for elderly persons, one of the major aims should be to improve and rehabilitate gait characteristics after long-term repeated use of the device. However, most of the existing research on walking assistive devices only emphasize their immediate effects, and there is limited research indicating the long-term effects. To address this gap, this paper experimentally validates the effects of our soft wearable robotic suit on gait characteristics of elderly persons after repeated use of the device for six weeks. Experimental results on four elderly subjects (age = 74.8 ± 5.0 year) show that, after six weeks of gait rehabilitation training by the robotic suit, the gait characteristics of the subjects were improved, leading to an increased walk ratio with an average of 9.8% compared with the initial state. The results of this research will benefit the potential use of the robotic suit in gait training and rehabilitation for elderly persons and also will be useful to the establishment of practical guidelines that maximize the training and rehabilitation effectiveness of the robotic suit.

The purpose of this paper is to present solution to an ill-posed problem for a muscular internal force feedforward positioning method of a musculoskeletal system. In our previous research, the muscular internal force feedforward positioning method of the musculoskeletal system has been proposed. In the method, the position regulation of the system can be accomplished by inputting a desired internal force balancing at a desired position. However, this control method has the ill-posed problem that the muscular internal force balancing at the desired position cannot be uniquely determined because the musculoskeletal system has muscular redundancy. A determination method of the muscular internal force is an important problem because a convergence and responsiveness of the system are influenced by the muscular internal force. Therefore, this study proposes a new determination method of the muscular internal force using reinforcement learning technique in order to determine the muscular internal force uniquely by considering control performance of the system. The proposed method numerically determines the muscular internal force that can converge at a desired position smaller than a conventional method. Its effectiveness is shown through numerical simulations for reaching movements of the musculoskeletal system.

This paper discusses the efficiency and completeness of a sweeping task to ensure the reliability of sweeping robots. The map information is necessary in order to ensure the completeness of sweeping, but it is not practical to give the preliminary map information to the robot. When the robot generates the map online, the reliability of the map is low in the beginning of the sweeping task. Therefore, the robot cannot use globally motion control. In the latter half of sweeping, unswept area are scattered like detached lands. The map has high reliability at this time, and the motion control using the whole map information is effective. The reliability of the map is gradually increased during the sweeping task, the robot should switch the motion control from locally to globally in accordance with it. In this paper, we propose the new motion control method for a sweeping robot in unknown environments. The robot selects mainly local motion control method at an early stage in this algorithm. As time goes on, the probability of the global motion control method selecting is increased. Even though the robot does not know the area of environment, the robot behaves as the above. Simulation and experimental results show the proposed method is more effective than the behavior-based method.

Nonsmooth mechanical systems, which are mechanical systems involving dry friction and rigid unilateral contact, are usually described as differential inclusions (DIs), that is, differential equations involving discontinuities. Those DIs may be approximated by ordinary differential equations (ODEs) by simply smoothing the discontinuities. Such approximations, however, can produce unrealistic behaviors because the discontinuous natures of the original DIs are lost. This paper presents a new algebraic procedure to approximate DIs describing nonsmooth mechanical systems by ODEs with preserving the discontinuities. The procedure is based on the fact that the DIs can be approximated by differential algebraic inclusions (DAIs), and thus they can be equivalently rewritten as ODEs. The procedure is illustrated by some examples of nonsmooth mechanical systems with simulation results obtained by the fourth-order Runge-Kutta method.

This paper presents the results of quantitative performance evaluation of an authors’ new parabolic sliding mode filter, which is for removing noise from signals in robotics and mechatronics applications, based on the frequency and time domain characteristics. Based on the evaluation results, the paper presents selection guidelines of two parameters of the filter. The evaluation results show that, in the frequency domain, the noise removing capability of the filter is almost the same as that of the second-order Butterworth low-pass filter (2-LPF), but its phase lag is smaller (maximum 150 degree) than that of 2-LPF (maximum 180 degree). Moreover, the filter produces smaller phase lag than a conventional parabolic sliding mode filter with appropriate selection of the parameters. In the time domain, the filter produces smaller overshoot than 2-LPF and the conventional one, while maintaining short transient time, by using an appropriately selected parameter. The presented parameter selection guidelines state that the values of the parameters should be chosen according to some estimated characteristics of the input and some desired characteristics of the output. The effectiveness of the filter and the presented guidelines is validated through numerical examples and their application to a closed-loop, force control of a robot manipulator.

Kawasaki disease (KD) causes vascular injury and lifelong remodeling. Excessive intimal proliferation has been observed, resulting in coronary artery lesions (CALs). However, the mechanisms underlying vascular remodeling in CAL and statin treatment have not been comprehensively elucidated. This study aimed to investigate the effects of statins on vascular remodeling using a KD mouse model. Candida albicans water-soluble substance (CAWS) was intraperitoneally injected in 5-week-old male apolipoprotein-E-deficient mice. They were categorized as follows (n = 4): control, CAWS, CAWS+statin, and late-statin groups. The mice were euthanized at 6 or 10 weeks after injection. Statins (atorvastatin) were initiated after CAWS injection, except for the late-statin group, for which statins were internally administered 6 weeks after injection. Elastica van Gieson staining and immunostaining were performed for evaluation. Statins substantially suppressed the marked neointimal hyperplasia induced by CAWS. Additionally, CAWS induced TGFβ receptor II and MAC-2 expression around the coronary arteries, which was suppressed by the statins. KD-like vasculitis might promote the formation of aneurysm by destroying elastic laminae and inducing vascular stenosis by neointimal proliferation. The anti-inflammatory effects of statins might inhibit neointimal proliferation. Therefore, statin therapy might be effective in adult patients with KD with CAL by inhibiting vascular remodeling., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Objectives: This study aimed to investigate incidence and risk factors for permanent pacemaker implantation for sick sinus syndrome( SSS) after maze procedure., Methods: Medical records of 59 patients who underwent maze procedure for atrial fibrillation at our hospital from 2018 to 2022 were retrospectively reviewed., Results: Mean age was 70 years and 32 patients (54%) were male. Major cardiac procedure was mitral valve surgery in 43( 72%). Radiofrequency ablation device was used in 35( 59%) and cryoablation was used in 24 (41%). Nineteen patients (32%) required temporary pacing after surgery;7 for type Ⅰ or Ⅱ SSS, 9 for type Ⅲ SSS and 3 for bradycardiac atrial fibrillation. Of these, all the 7 patients with type Ⅰ or Ⅱ SSS regained sinus rhythm, whereas 2 with type Ⅲ SSS underwent permanent pacemaker implantation. Overall, permanent pacemaker was implanted in 3( 5%). Forty-six patients( 78%) were in sinus rhythm at the outpatient clinic after surgery., Conclusions: Type Ⅰ or Ⅱ SSS after maze procedure is likely to resume sinus rhythm at the time of discharge whereas type Ⅲ is not. For type Ⅲ SSS after maze procedure, adequate anti-arrhythmic medication early after surgery may be required to avoid permanent pacemaker implantation.

Objective: This single-center retrospective study evaluated early and midterm outcomes of 100 consecutive patients with type A intramural hematoma., Methods: Initial watch-and-wait strategy was indicated if the maximum aortic diameter was < 50 mm, pain score was < 3/10 on the numerical rating scale, and no ulcer-like projection was observed in the ascending aorta. The primary endpoints of this study were all-cause and aorta-related deaths, and the secondary endpoint was aortic events., Results: Initial watch-and-wait strategy was indicated in 52 patients. Emergency aortic repair was indicated in the remaining 48 patients; 2, 31, and 15 patients died before surgery, underwent emergency surgery, and declined emergency surgery, respectively. Among the watch-and-wait group, 11 (21%) patients underwent aortic repair during hospitalization. In-hospital mortality rates, 5-year survival rates, and 5-year freedom from aorta-related death were not significantly different between the initial watch-and-wait strategy and emergency surgery (2% vs. 6%, 92% vs. 82%, and 100% vs. 94%, respectively). In the initial watch-and-wait strategy group, 5-year freedom from aortic events and freedom from aortic events involving the ascending aorta were 60% and 66%, respectively., Conclusions: The early and midterm outcomes with the initial watch-and-wait strategy in patients with type A intramural hematoma with a maximum aortic diameter of ≤ 50 mm, pain score of ≤ 3/10, and no ulcer-like projection in the ascending aorta were favorable with no aorta-related death., (© 2023. The Author(s), under exclusive licence to The Japanese Association for Thoracic Surgery.)

Objectives: This study aimed to investigate changes in haematoma thickness during the early period and their association with disease progression in patients who received initial medical treatment for type A intramural haematoma (IMH)., Methods: Medical records and serial computed tomography angiography (CTA) images of patients who did not undergo emergency aortic repair for type A IMH upon presentation were retrospectively reviewed. The haematoma remodelling rate was determined using the following equation: thickness of the haematoma on the first CTA (mm) - thickness of the haematoma on the second CTA (mm)time between the first and second CTAs (h)., Results: Among the 40 patients included in this study, 38 were indicated for initial watch-and-wait strategy, whereas 2 were indicated for emergency aortic repair but declined it. During hospitalization, 10 patients developed disease progression, with 2 in-hospital mortality cases. Analysis of the haematoma remodelling rate in 39 patients revealed that such a rate was significantly associated with the reciprocal of the time from onset. Analysis of all 70 CTA examinations performed within 24 h after the onset of IMH showed that haematoma thickness was significantly associated with the logarithm of the time from onset. Initial regression of the haematoma was not necessarily associated with avoidance of disease progression., Conclusions: In type A IMH, the thickness of the haematoma in the ascending aorta tended to decrease in the very early period; however, prompt regression of the haematoma was not necessarily associated with avoidance of disease progression., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: The standard treatment for Kawasaki disease is immunoglobulin therapy, but the high frequency of coronary sequelae in immunoglobulin-refractory cases indicates a need for further improvement in treatment., Methods: Kawasaki disease-like vasculitis was induced in 5-week-old DBA/2 mice by intraperitoneal administration of 0.5 mg Candida albicans water-soluble fraction (CAWS) daily for 5 days followed by daily administration of candesartan, an angiotensin receptor blocker. The vasculitis suppression effect was confirmed histologically and serologically in mice sacrificed at 28 days after the start of candesartan., Results: The area of inflammatory cell infiltration at the aortic root was 2.4±1.4% in the Control group, 18.1±1.9% in the CAWS group, and 7.1±2.3%, 5.8±1.4%, 7.6±2.4%, and 7.9±5.0% in the CAWS+candesartan 0.125-mg/kg, 0.25-mg/kg, 0.5-mg/kg, and 1.0-mg/kg groups, respectively (p=0.0200, p=0.0122, p=0.0122, and p=0.0200 vs. CAWS, respectively). The low-dose candesartan group also showed significantly reduced inflammatory cell infiltration. A similar trend was confirmed by immunostaining of macrophages and TGFβ receptors. Measurement of the inflammatory cytokines IL-1β, IL-6, and TNF-α confirmed the anti-vasculitis effect of candesartan., Conclusions: Candesartan inhibited vasculitis even at clinical doses used in children, making it a strong future candidate as an additional treatment for immunoglobulin-refractory Kawasaki disease.

Background: Intracardiac thrombus is relatively rare in patients with coronavirus disease 2019 (COVID-19). However, if it occurs, thrombotic complications are likely to develop. In this case, we performed a successful thrombectomy on a patient who developed left ventricular thrombus after COVID-19 infection without complications., Case Presentation: A 52-year-old man sought medical care due to fever, dyspnea, and abnormalities in the taste and smell that persisted for 2 weeks. The patient was diagnosed with COVID-19 and was treated with remdesivir, baricitinib, and heparin. Three weeks after hospitalization, electrocardiogram revealed angina pectoris, and cardiac catherization showed left anterior descending coronary artery stenosis. In addition, global hypokinesis and a thrombus at the left ventricular apex were observed on echocardiography. Left ventricular reconstruction concomitant with coronary artery bypass grafting was performed. A thrombus in the left ventricle was resected via left apical ventriculotomy, and the bovine pericardium was covered and sutured on the infarction site to exclude it. The patient was extubated a day after surgery and was transferred to another hospital for recuperation after 20 days. He did not present with complications., Conclusions: Thrombotic events could be prevented via thrombectomy with left ventricular reconstruction using an intraventricular patch to exclude the residual thrombus., (© 2023. The Author(s).)

Background: Although surgical approaches for infected or failing cardiac implantable electronic device (CIED) leads are more invasive than transvenous approaches, they are still required for patients considered unsuitable for transvenous procedures. In this study, surgical management with transvenous equipment for CIED complications was examined in patients unsuitable for transvenous lead extraction., Methods and results: We retrospectively examined 152 consecutive patients who underwent CIED extraction between April 2009 and December 2021 at the Department of Cardiovascular Surgery, Nippon Medical School. Nine patients (5.9%; mean [±SD] age 61.7±16.7 years) who underwent open heart surgery were identified as unsuitable for the isolated transvenous approach. CIED types included 5 pacemakers and 4 implantable cardioverter-defibrillators; the mean [±SD] lead age was 19.5±7.0 years. Indications for surgical management according to Heart Rhythm Society guidelines included failed prior to transvenous CIED extraction (n=6), intracardiac vegetation (n=2), and severe lead adhesion (n=1). Transvenous CIED extraction tools were used in all patients during or before surgery. Additional surgical procedures with CIED extraction included epicardial lead implantation (n=4) and tricuspid valve repair (n=3). All patients were discharged; during the follow-up period (mean 5.7±3.7 years), only 1 patient died (non-cardiac cause)., Conclusions: Surgical procedures and transvenous extraction tools were combined in the removal strategy for efficacious surgical management of CIED leads. Intensive surgical procedures were safely performed in patients unsuitable for transvenous extraction.

Kawasaki disease (KD) is an acute inflammatory syndrome of unknown etiology that is complicated by cardiovascular sequelae. Chronic inflammation (vasculitis) due to KD might cause vascular cellular senescence and vascular endothelial cell damage, and is a potential cause of atherosclerosis in young adults. This study examined the effect of KD and HMG-CoA inhibitors (statins) on vascular cellular senescence and vascular endothelial cells. Candida albicans water-soluble fraction (CAWS) was administered intraperitoneally to 5-week-old male apolipoprotein E-deficient (ApoE-) mice to induce KD-like vasculitis. The mice were then divided into three groups: control, CAWS, and CAWS+statin groups. Ten weeks after injection, the mice were sacrificed and whole aortic tissue specimens were collected. Endothelial nitric oxide synthase (eNOS) expression in the ascending aortic intima epithelium was evaluated using immunostaining. In addition, eNOS expression and levels of cellular senescence markers were measured in RNA and proteins extracted from whole aortic tissue. KD-like vasculitis impaired vascular endothelial cells that produce eNOS, which maintains vascular homeostasis, and promoted macrophage infiltration into the tissue. Statins also restored vascular endothelial cell function by promoting eNOS expression. Statins may be used to prevent secondary cardiovascular events during the chronic phase of KD., Competing Interests: The authors declare no conflict of interest.

A case of a giant popliteal venous aneurysm that caused massive pulmonary thromboembolism with an arteriovenous fistula draining into the adjacent proximal femoral vein is reported herein. Deep veins in the lower leg were occluded by thrombi. The inlet and outlet orifice inside the aneurysm was closed and aneurysmorraphy was performed. The fistula was retained on the estimation that it would maintain the blood flow and prevent thrombus formation inside the femoral vein. The aneurysm was shrunk, the femoral vein was patent, and the fistula was not observed 1 year later, although it still existed 1 week after the operation., Competing Interests: Disclosure Statement (COI)The authors do not have any conflicts of interest to declare., (© 2022 The Editorial Committee of Annals of Vascular Diseases.)

Background: Obesity-related exercise intolerance may be associated with pulmonary vascular and right ventricular dysfunction. This study tested the hypothesis that decreased pulmonary vascular reserve and right ventricular (RV)-pulmonary arterial (PA) uncoupling contributes to exercise limitation in subjects with obesity., Methods: Seventeen subjects with obesity were matched to normo-weighted healthy controls. All subjects underwent; exercise echocardiography, lung diffusing capacity (DL) for nitric oxide (NO) and carbon monoxide (CO) and an incremental cardiopulmonary exercise test. Cardiac output (Q), PA pressure (PAP) and tricuspid annular plane systolic excursion (TAPSE) were recorded at increasing exercise intensities. Pulmonary vascular reserve was assessed by multipoint mean PAP (mPAP)/Q relationships with more reserve defined by lesser increase in mPAP at increased Q, and RV-PA coupling was assessed by the TAPSE/systolic PAP (sPAP) ratio., Results: At rest, subjects with obesity displayed lower TAPSE/sPAP ratios (1.00 ± 0.26 vs. 1.19 ± 0.22 ml/mmHg, P < 0.05), DL CO and pulmonary capillary blood volume (52 ± 11 vs. 64 ± 13 ml, P < 0.01) compared to controls. Exercise was associated with steeper mPAP-Q slopes, decreased TAPSE/sPAP and lower peak O 2 uptake (VO 2 peak). The changes in TAPSE/sPAP at exercise were correlated to the body fat mass ( R = 0.39, P = 0.01) and VO 2 peak ( R = 0.44, P < 0.01)., Conclusion: Obesity is associated with a decreased pulmonary vascular and RV-PA coupling reserve which may impair exercise capacity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Na, Kevin, Yoshiki, Corentin, Malgorzata, Robert and Vitalie.)

Background: Scoliosis is one of the symptoms manifested by patients with Marfan syndrome (MFS). Deformity of the thoracic cavity due to severe scoliosis may cause difficulty during cardiac surgery in terms of the surgical approach and instrument manipulation; however, only a few reports have been available regarding the surgical case of MFS with severe scoliosis. Here, we report a case of combined aortic valve replacement and left atrial appendage closure in a patient with MFS who had severe scoliosis using lower hemisternotomy., Case Presentation: A 62-year-old female with MFS was referred to our hospital after being diagnosed with severe aortic regurgitation and paroxysmal atrial fibrillation with a history of cerebral thromboembolism. The aortic valve showed severe insufficiency due to cusp prolapse, whereas the aortic root was moderately dilated (42 mm). Echocardiography revealed severe regurgitation with reduced left ventricular ejection function (32%) and massive left ventricular diastolic dimension (88 mm). Moreover, combined aortic valve replacement and left atrial appendage closure was indicated. However, the patient had chest deformity due to severe scoliosis. Thus, conventional full sternotomy or thoracotomy was considered an inappropriate surgical approach. Lower hemisternotomy was selected on the basis of three-dimensional reconstruction imaging of the aorta, left atrial appendage, sternum, and rib. Sternal elevation and rib retraction with the costal arch folded back provided enough surgical field for the combined procedures to be safely conducted. The postoperative course was uneventful, except for predicted prolonged mechanical ventilation with the assistance of intraaortic balloon pumping. Thereafter, the patient has been free from any cardiac and cerebrovascular event., Conclusions: Lower hemisternotomy can be useful for combined cardiac surgery in MFS with severe scoliosis., (© 2022. The Author(s).)

Kawasaki disease (KD) is an acute form of systemic vasculitis that may promote atherosclerosis in adulthood. This study examined the relationships between KD, atherosclerosis, and the long-term effects of HMG-CoA inhibitors (statins). Candida albicans water-soluble fraction (CAWS) was injected intraperitoneally into 5-week-old male apolipoprotein-E-deficient (Apo E-/-) mice to create KD-like vasculitis. Mice were divided into 4 groups: the control, CAWS, CAWS+statin, and late-statin groups. They were sacrificed at 6 or 10 weeks after injection. Statin was started after CAWS injection in all groups except the late-statin group, which was administered statin internally 6 weeks after injection. Lipid plaque lesions on the aorta were evaluated with Oil Red O. The aortic root and abdominal aorta were evaluated with hematoxylin and eosin staining and immunostaining. CAWS vasculitis significantly enhanced aortic atherosclerosis and inflammatory cell invasion into the aortic root and abdominal aorta. Statins significantly inhibited atherosclerosis and inflammatory cell invasion, including macrophages. CAWS vasculitis, a KD-like vasculitis, promoted atherosclerosis in Apo E-/- mice. The long-term oral administration of statin significantly suppressed not only atherosclerosis but also inflammatory cell infiltration. Therefore, statin treatment may be used for the secondary prevention of cardiovascular events during the chronic phase of KD.

Aims: To explore the effects of age and sex in adolescents vs. young or middle-aged adults on pulmonary vascular function and right ventricular-arterial (RV-PA) coupling as assessed by exercise stress echocardiography., Methods and Results: Forty healthy adolescents aged 12-15 years were compared with 40 young adults aged 17-22 years and 40 middle-aged adults aged 30-50 years. Sex distribution was equal in the three groups. All the subjects underwent an exercise stress echocardiography. A pulmonary vascular distensibility coefficient α was determined from multipoint pulmonary vascular pressure-flow relationships. RV-PA coupling was assessed by the tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary artery pressure (PASP) ratio, who has been previously validated by invasive study. While cardiac index and mean PAP were not different, adolescents compared to young and middle-aged adults, respectively had higher pulmonary vascular distensibility coefficients α (1.60 ± 0.31%/mmHg vs. 1.39 ± 0.29%/mmHg vs. 1.20 ± 0.35%/mmHg, P < 0.00001). Adolescents and young adults compared to middle-aged adults, respectively had higher TAPSE/PASP ratios at rest (1.24 ± 0.18 mm/mmHg and 1.22 ± 0.17 mm/mmHg vs. 1.07 ± 0.18 mm/mmHg, P < 0.008) and during exercise (0.86 ± 0.24, 0.80 ± 0.15 and 0.72 ± 0.15 mm/mmHg, P < 0.04). The TAPSE/PASP ratio decreased with exercise. There were no sex differences in α or TAPSE/PASP., Conclusion: Compared to adults, adolescents present with a sex-independent more distensible pulmonary circulation. Resting and exercise RV-PA coupling is decreased in middle-aged adults., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)

Objectives: Uncomplicated type B acute aortic dissection (UTBAAD) has traditionally been treated medically. Although patients are treated based on the rehabilitation program established by the Japanese Circulation Society, we sometimes encounter patients with complications related to the long duration of bed rest. We performed novel fast-track rehabilitation for UTBAAD, which consisted of short-duration bed rest and the early initiation of walking under secure blood pressure control., Methods and Results: From April 2009 to February 2017, there were 73 consecutive cases of UTBAAD. Conventional medical treatment was administered to 39 patients (group G) during the early period. From August 2013, 34 patients (group F) received our 'fast-track' rehabilitation program, which consisted of the following: oral intake and assuming a sitting position from day 1 after the onset, standing by the bed from day 2, walking in their room from day 4, and discharge from day 16 if all goes smoothly. Group F had a significantly earlier initiation of standing and walking, first defecation, and weaning from oxygen and intravenous antihypertensive agents than group G. The pneumonia complication rate was significantly lower in group F than in group G. The hospitalization duration was markedly shorter and the in-hospital expense lower in group F than in group G. There were no significant differences in the rate of late adverse aortic events within 12 months after onset., Conclusions: Our fast-track rehabilitation program for patients with UTBAAD resulted in a better in-hospital clinical course and lower expense than conventional medical treatment without any adverse aortic events.

We report a case of stent graft occlusion, severe lower extremity ischemia, and ruptured abdominal aortic aneurysm due to type B acute aortic dissection 3 years after endovascular aneurysm repair. He admitted our hospital because of abrupt back pain and dysesthesia of bilateral lower limb. Contrast-enhanced computed tomography (CT) scan showed type B acute aortic dissection and occlusion of the stent graft due to dynamic compression by the false lumen. Emergent right axillo-bifemoral bypass operation was done for his critical limb ischemia. Immediately after the successful operation, he fell into shock vital and dissecting abdominal aortic aneurysm rupture was revealed by CT scan. We performed the stump occlusion of the infrarenal abdominal aorta and the bilateral common iliac arteries by abdominal midline incision. Postoperative myonephropathicmetabolic syndrome due to the left ischemia resulted in amputation of his left lower leg for lifesaving. While EVAR cases are increasing, various its complications come to be reported. We consider that this case report might be cautious about the indication of EVAR for the younger generation. (This is a translation of Jpn J Vasc Surg 2019; 28: 367-371.)., Competing Interests: Disclosure StatementNone of the authors have any conflicts of interest to declare., (© 2020 The Editorial Committee of Annals of Vascular Diseases.)

An 80-year-old woman was incidentally found to have a cardiac tumor on the aortic valve by echocardiography. Papillary fibroelastoma(PFE) was strongly suspected, and urgent operation was performed to prevent embolism. Two tumors were identified arising from the left and right cusps with wide stalks, and aortic valve replacement was performed. By pathological examination, the tumors were diagnosed as PFEs. A small tumor was also found on the non-coronary cusp, which was considered as possible PFE or Lambl's excrescence. In the case of multiple PFEs on one valve, valve replacement, instead of simple excision of tumors, should be considered.

Objectives: Pulmonary hypertension (PH) is characterized by marked and sustained elevation of pulmonary vascular resistance and pulmonary artery pressure, and subsequent right-sided heart failure. Right ventricular (RV) function and exercise capacity have been recognized as important prognostic factors for PH. Our aim was to investigate RV contractile reserve and exercise capacity during a leg-positive pressure (LPP) maneuver., Methods: The study population comprised 43 PH patients and 17 normal controls. All patients underwent echocardiography at rest and during LPP stress. Exercise capacity was assessed by 6-minute walk distance for PH patients. RV relative wall thickness was calculated from dividing by RV free wall thickness by basal RV linear dimensions at end-diastole. RV function was calculated by averaging peak speckle-tracking longitudinal strain from the RV free wall. RV contractile reserve was assessed as the difference in RV free wall strain at rest and during LPP stress. Changes in left ventricular stroke volume (ΔSV) during LPP stress were also calculated., Results: ΔSV and RV contractile reserve of PH patients were significantly lower than of controls (3.6 ± 6.0 mL vs 8.5 ± 2.3 mL, and 8.2 ± 11.9% vs 14.5 ± 6.6%; both P < 0.01). RV contractile reserve of PH patients with ΔSV <3.3 mL was significantly lower than of PH patients with ΔSV >3.3 mL (3.9 ± 13.2% vs 12.3 ± 8.9%; P = 0.02). ΔSV had also significant correlation with 6-minute walk distance (r = 0.42, P = 0.006). Multivariate regression analysis showed that RV relative wall thickness was an independent determinant parameter of ΔSV during LPP stress for PH patients (β = 3.2, P = 0.003)., Conclusions: Preload stress echocardiography in response to LPP maneuver, a noninvasive and easy-to-use procedure for routine clinical use, proved to be useful for the assessment of RV contractile reserve and exercise capacity of PH patients., (© 2018 Wiley Periodicals, Inc.)

Background: This study compared the diagnostic value of myocardial perfusion imaging (MPI) between the rest-stress 99 m Tc-tetrofosmin protocol (Tc/Tc protocol) and simultaneous acquisition rest 99 m Tc-tetrofosmin/stress 201 Tl dual-isotope protocol (SDI protocol) with a semiconductor camera.Methods and Results: We retrospectively studied 147 patients who underwent stress MPI using a cadmium-zinc-telluride camera and invasive coronary angiography within a 3-month interval. The Tc/Tc and SDI protocols were used in 59 and 88 patients, respectively. The sensitivity, specificity, and accuracy of the summed difference score in per-patient analysis were 56%, 85%, and 69%, respectively, for the Tc/Tc protocol and 89%, 82%, and 85%, respectively, for the SDI protocol. The area under the receiver operating characteristic curve was significantly better for the SDI than Tc/Tc protocol for the left anterior descending artery (0.836 vs. 0.674; P=0.0380), the left circumflex artery (0.754 vs. 0.599; P=0.0441), and in per-patient analysis (0.875 vs. 0.707; P=0.0135). There was no significant difference in the diagnostic accuracy of the summed stress score for any vessel or in per-patient analysis between the 2 protocols., Conclusions: The SDI protocol had a higher diagnostic accuracy for the detection of coronary ischemia than the Tc/Tc protocol.

New Findings: What is the central question of this study? Right ventricular dyssynchrony in severe pulmonary hypertension is associated with a poor prognosis. However, it has recently been observed in patients with lung or connective tissue disease and pulmonary artery pressure at the upper limits of normal. The mechanisms of right ventricular dyssynchrony in pulmonary hypertension remain uncertain. What is the main finding and its importance? Acute hypoxic breathing, but not normoxic exercise, induces an increase in right ventricular dyssynchrony detected by speckle tracking echocardiography in healthy subjects. These results add new insights into the determinants of right ventricular dyssynchrony, suggesting a role for systemic factors added to afterload in the pathophysiology of right ventricular inhomogeneity of contraction., Abstract: Pulmonary hypertension (PH) has been shown to be associated with regional inhomogeneity (or dyssynchrony) of right ventricular (RV) contraction. Right ventricular dyssynchrony is an independent predictor of decreased survival in advanced PH, but has also been reported in patients with only mildly elevated pulmonary artery pressure (PAP). The mechanisms of RV dyssynchrony in PH remain uncertain. Our aim was to evaluate RV regional function in healthy subjects during acute hypoxia and during exercise. Seventeen healthy subjects (24 ± 6 years) underwent a speckle tracking echocardiography of the RV at rest in normoxia and every 15 min during a 60 min exposure to hypoxic breathing ( F I O 2 12%). Ten of the subjects also underwent an incremental cycle ergometry in normoxia to 100 W, with the same echocardiographic measurements. Dyssynchrony was measured as the SD of the times to peak systolic strain of the four basal and mid RV segments corrected for the heart rate (RV-SD4). RV-SD4 increased during hypoxia from 12 ± 7 to 22 ± 11 ms in spite of mild increases in mean PAP (mPAP) from 15 ± 2 to 20 ± 2 mmHg and pulmonary vascular resistance (PVR) from 1.18 ± 0.15 to 1.4 ± 0.15 Wood units (WU). During exercise RV-SD4 did not significantly change (from 12 ± 6 ms to 14 ± 6 ms), while mPAP increased to 25 ± 2 mmHg and PVR was unchanged. These data show that in healthy subjects, RV contraction is inhomogeneous in hypoxia but not during exercise. Since PAP increases more during exercise, RV dyssynchrony in hypoxia may be explained by a combination of mechanical (RV afterload) and systemic (hypoxia) factors., (© 2018 The Authors. Experimental Physiology © 2018 The Physiological Society.)

Systemic hypertension is a risk factor for left heart failure, mostly with preserved ejection fraction. Left heart failure is a cause of pulmonary hypertension and eventual right ventricular (RV) failure. There has been report of altered RV function in mild to moderate hypertension with preserved systolic as well as diastolic function of the left ventricle. The pathophysiology of this complication of hypertension is unclear. Preserving the RV and preventing the development of pulmonary vascular disease may be considered among the targets of optimized therapy for systemic hypertension., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aim: A fluid challenge with rapid saline infusion during right heart catheterization has been shown to be useful for the differential diagnosis between pre- and post-capillary pulmonary hypertension. The aim of this study was to evaluate the prognostic relevance of fluid challenge-induced changes in pulmonary hemodynamics in patients with pulmonary arterial hypertension (PAH)., Methods: Overall, 118 PAH patients (mean age 57 ± 15 years, 80 female) underwent hemodynamic measurements before and after rapid saline infusion (7 mL/kg in 10 min) and were followed up for 19 ± 4 months., Results: Thirty-two patients (27%) had a clinical worsening event defined as the occurrence of one of the following: death, lung transplantation, initiation of parenteral prostanoids, or worsening of PAH (defined as the presence of all of the three following components: a decrease in the 6-minute walk distance of at least 15% from baseline, worsening of PAH symptoms, and need for new PAH treatment). Cardiac index (CI), stroke volume and pulmonary artery compliance were lower whereas right atrial pressure (RAP), the ratio of RAP to pulmonary artery wedge pressure (PAWP) and pulmonary vascular resistance were higher in patients with a clinical worsening event versus patients without events, both at baseline and after fluid challenge (all p < 0.01). At multivariable Cox proportional hazards regression analysis, a post-fluid challenge CI <2.8 L/min/m 2 (hazard ratio 0.0143; 95% confidence interval 0.006-0.3383; p = 0.009) was the only independent predictor of outcome., Conclusions: CI measured after a fluid challenge is an independent predictor of outcome in PAH., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: The closure of atrial septal defect (ASD) results in normalized left ventricular (LV) and right ventricular (RV) geometry, and can increase LV stroke volume (LVSV), but the parameters associated with this increase after the closure of ASD remain uncertain., Methods: Seventy ASD patients, who underwent transcatheter closure, were studied. Their mean age was 57.80 ± 16.88 years, 42 (60%) were female, and LV ejection fraction (LVEF) was 66.76% ± 7.91% (all ≥55%). Transthoracic echocardiography was performed before and 3 months after the procedure. Global longitudinal strain (GLS) was determined as the average peak speckle tracking strain of 18 segments from the 3 standard apical views, LV dispersion was defined as standard deviation of time-to-peak strain from the same views, and RV systolic function was calculated by averaging the 3-regional peak speckle tracking longitudinal strains from the RV free wall. A significant relative increase in LVSV between before and 3 months after the closure was defined as ∆LVSV ≥15%. Twenty age-, gender-, and LVEF-matched controls served as the control group., Results: Global longitudinal strain (GLS) and RV free wall strain were similar for ASD patients and controls, but LV dispersion in ASD patients was significantly larger. Global longitudinal strain (GLS) remained unchanged after transcatheter closure, whereas RV free wall strain and LV dispersion decreased significantly. An important finding of the multivariate logistic regression analysis showed that ∆LV dispersion was the only independent determinant of increased LVSV after the closure (OR 1.023; 95% CI 1.001-1.046; P < .01)., Conclusions: The assessment of LV dispersion may well have clinical implications for better management of ASD patients after transcatheter closure., (© 2017, Wiley Periodicals, Inc.)

Intracranial cerebral atherosclerosis is a significant predictor of stroke after coronary artery bypass grafting (CABG). However, there is limited information on intracranial occlusive lesions in patients undergoing CABG. The purpose of the study was to elucidate the precise prevalence and distribution of occlusive lesions of the extracranial and intracranial arteries in patients undergoing CABG. Between 2009 and 2016, 205 patients underwent preoperative magnetic resonance angiography and elective CABG. The prevalence and the distribution of occlusive lesions were retrospectively examined by preoperative magnetic resonance angiography. Association between postoperative central nervous system (CNS) complications and the occlusive lesions was analyzed. Fifty-six patients (27.3%) and 60 patients (29.3%) had occlusive lesions of the extracranial and intracranial arteries, respectively. Twenty-eight patients (13.7%) had both extracranial and intracranial occlusive lesions. Thirty-one (15.1%) and 45 (22.0%) patients had severe stenosis or occlusion of the extracranial and intracranial arteries, respectively. The intracranial internal carotid artery was the most commonly affected intracranial artery (60 vessels; 62.5%), followed by the middle cerebral arteries (20 vessels; 20.8%). Sixteen patients (7.8%) suffered from postoperative CNS complications, including 2 permanent strokes. The etiology of the stroke was attributable to a predefined intracranial lesion in 1 patient. In multivariate analysis, the presence of intracranial occlusive lesions was found to have an independent association with the development of CNS complications (odds ratio 4.05; 95% confidence interval 1.13-14.6). The prevalence of intracranial occlusive lesions was higher than that of extracranial lesions in patients undergoing CABG. There was a solid trend toward the anterior distribution of the intracranial occlusive lesions., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Left ventricular (LV) diastolic dysfunction and longitudinal systolic dysfunction were identified in patients with diabetes mellitus (DM). This study's aim was to investigate the impact of LV longitudinal systolic function on LV diastolic function in DM patients with preserved LV ejection fraction (LVEF). We studied 177 DM patients with preserved LVEF (all ≥50%), and 82 age-, gender- and LVEF-matched healthy volunteers as control. Global longitudinal strain (GLS) was defined as the average peak strain of 18 segments from standard apical views, GLS <18% as subclinical LV systolic dysfunction (LVSD), and LV dispersion as the standard deviation of time-to-peak strain from the same views. For DM patients with LVSD (n = 74), E/A and E' were lower, and E/E' and isovolumic relaxation time (IVRT) were greater than for DM patients without LVSD (n = 103) and normal controls (n = 82). Moreover, these parameters were lower for DM patients without LVSD than for normal controls. Multivariate analysis revealed that GLS was a strong determinative factor for E' and E/E' (β = 0.30, p < 0.001 and β = -0.25, p < 0.001, respectively), as was LV dispersion for E-wave deceleration time and IVRT (β = 0.21, p = 0.002 and β = 0.30, p < 0.001, respectively) independently of age. For normal subjects, however, only age was associated with all LV diastolic parameters. In conclusions, in contrast to age-related LV diastolic dysfunction in normal subjects, in DM patients with preserved LVEF, LV diastolic function was associated with LV longitudinal systolic function and LV dispersion independently of age. Our findings have obvious clinical implications for the management of DM patients.

Although right ventricular (RV) pacing is the only effective treatment for patients with symptomatic bradycardia, it creates left ventricular (LV) dyssynchrony, which can induce LV dysfunction and heart failure. The current criterion for consideration of cardiac resynchronization therapy (CRT) is LV ejection fraction (LVEF) ≤ 35%, but indication for CRT in patients required for RV pacing with LVEF > 35% remains unclear.We studied 40 patients, all LVEF ≥ 35%, who had undergone implantable cardioverter-defibrillator implantation with RV pacing < 5%. Echocardiography was performed at baseline and during RV pacing. LV dyssynchrony was defined as anteroseptal-to-posterior wall delay from the mid-LV short-axis view using two-dimensional speckle-tracking radial strain (significant: ≥ 130 ms). Patients were divided into two groups based on baseline LVEF: normal LVEF ( ≥ 50%; n = 20) and mildly reduced LVEF (35-50%; n = 20).LVEF and LV dyssynchrony in patients with mildly reduced LVEF deteriorated significantly during RV pacing compared to those in patients with normal LVEF. Moreover, changes in LV dyssynchrony during RV pacing significantly correlated with changes in LVEF (r = -0.44, P < 0.01). Multivariate logistic regression analysis showed that baseline LVEF was the only independent predictor and baseline LVEF < 48% predictive of significant LV dyssynchrony during RV pacing.The extent of RV pacing-induced LV dysfunction may be associated with baseline LV function. These adverse effects on patients with mildly reduced LVEF of 35-50% and indications for RV pacing due to bradycardia can thus be prevented by CRT.

Open repair for infra-renal abdominal aortic and iliac artery aneurysms (AAAs) is a robust treatment. On the other hand, endovascular aneurysm repair (EVAR) has been widespread because of its less invasiveness. However, patients after EVAR frequently require postoperative radiographic examinations and may feel anxiety for their endoleaks. We prospectively evaluated Health-related Quality of Life of the patients with these two fashions using the 8-item Short Form (SF-8). From 2011 to 2013, 89 consecutive elective cases of AAAs were treated. They were prospectively divided into EVAR and open repair groups but not randomly. The exclusion criteria were as follows: perioperative status for other surgeries, infectious aneurysm, severely deteriorated conditions, and patients who cannot answer for these questionnaire or show their consent. The SF-8 questionnaire was completed through interviews preoperatively, and at 1, 3, 6, and 12 months after treatment. The SF-8 questionnaire was completed for 55 cases [EVAR group (ER): 25, open repair group (OR): 30]. There was no significant difference between these groups regarding patients' characteristics except congestive heart disease. The preoperative scores of the SF-8 were similar in both groups except physical function and social function, which were lower in ER (p < 0.05). There was no operative death in both groups. Operative duration and hospital stay in EVAR were significantly shorter than those in OR (p < 0.05). Follow-up rate at 1, 3, 6, and 12 months was 100, 100, 68.0, and 64.0% in ER, and 100, 90.0, 80.0, and 66.6% in OR, respectively. During follow-up, both groups had no AAAs associated death. Regarding changes of the SF-8 scales, there were some trends at physical component summary score (PCS) and mental component summary score (MCS) in ER. The PCS decreased at 1 month, gradually increased at 3 months, and levelled off until 12 months. The MCS increased at 1 and 3 months, but gradually went down and almost stayed at the same level as preoperative one at 12 months. In OR, PCS and MCS decreased at 1 month and after that increased gradually at 3 and 6 months, and stayed the same at 12 months. The MCS recovered to preoperative score earlier than the PCS. In this study, EVAR did not show any significant mental disturbance based on the SF-8 for 1-year comparing to open repair.