Search

Increased extravascular lung water during ex vivo lung perfusion (EVLP) is associated with ischemia reperfusion injury and poor pulmonary function. A non-invasive technique for evaluating extravascular lung water during EVLP is desired to assess the transplant suitability of lungs. We investigated real-time lung weight measurements as a reliable method for assessing pulmonary functions in cellular EVLP using a porcine lung model.Fifteen pigs were randomly divided into 3 groups: control (no warm ischemia) or donation after circulatory death groups with 60 or 90 min of warm ischemia (n = 5, each). Real-time lung weight gain was measured by load cells positioned at the bottom of the organ chamber.Real-time lung weight gain at 2 h was significantly correlated with lung weight gain as measured on a back table (R = 0.979, P 0.01). Lung weight gain in non-suitable cases (n = 6) was significantly higher than in suitable cases (n = 9) at 40 min (51.6 ± 46.0 versus -8.8 ± 25.7 g; P 0.01, cutoff = +12 g, area under the curve = 0.907). Lung weight gain at 40 min was significantly correlated with PaO2/FiO2, peak inspiratory pressure, shunt ratio, wet/dry ratio, and transplant suitability at 2 h (P 0.05, each). In non-suitable cases, lung weight gain at 66% and 100% of cardiac output was significantly higher than at 33% (P 0.05).Real-time lung weight measurement could potentially be an early predictor of pulmonary function in cellular EVLP.

A reliable sternal fixation is one of the most basic parts of cardiac surgery requiring sternotomy for preventing wound complications and promoting early recovery. Although various products have been released to the markets, the characteristics of each device are still unclear.A simulation study was conducted to compare the properties of two sternal fixation device: a commonly used monofilament stainless-steel wire and a newly designed cable comprised of several titanium alloys strands. Sternum models made of monomer casting nylon were tied with each material and displaced in longitudinal, antero-posterior, and horizontal directions. Resistance against each directional external force was measured and compared.The titanium cable showed a higher resistance to every directional displacement since slight deviations and a twofold higher maximum strength than the stainless wire.An in vitro simulation study revealed the titanium cable system provide stronger sternum fixation than stainless-steel wire.

Objectives This study aimed to evaluate the outcomes of tricuspid annuloplasty with/without additional edge-to-edge plications in patients with functional tricuspid regurgitation and to clarify the impact of tethering on surgical outcomes. Methods This retrospective observational study included patients with moderate or greater functional tricuspid regurgitation who underwent initial tricuspid valve repair between January 2008 and December 2021. The patients were divided into two groups based on whether they had tethering (preoperative tethering area ≥0.75 cm2). All patients underwent annuloplasty, and edge-to-edge plications were added at the regurgitant leakage site identified by saline tests. The surgical outcomes of each group, and the effect of tethering on recurrent moderate or greater tricuspid regurgitation were evaluated. Results One-hundred and thirty-three patients were included in this study. During the follow-up period of 55.3 (standard deviation: 44.9) months, the 5-year survival rates were 78.4% in patients without tethering and 76.1% in patients with tethering (P = 0.78). The 5-year cumulative incidence rates of readmission for heart failure and recurrent tricuspid regurgitation were 10.8% and 1.3% in patients without tethering and 23.0% and 29.5% in patients with tethering, respectively (P = 0.12 and Conclusions In patients without tethering, annuloplasty and additional edge-to-edge plications are effective in avoiding recurrent tricuspid regurgitation with satisfactory midterm clinical outcomes. However, in patients with tethering, these procedures resulted in residual tethering, which could be leading to recurrent tricuspid regurgitation.

Thermography is a noninvasive technology to detect low temperatures in poorly circulated areas. In ex vivo lung perfusion (EVLP), lungs are rewarmed to body temperature during the initial 1 h. Currently, the effect of graft thermal changes during the rewarming phase on pulmonary function is unknown. In this study, we evaluated the correlation of lung surface temperature with physiological parameters, wet/dry ratio, and transplant suitability in Lund-type EVLP.Fifteen pigs were divided into three groups: control group (no warm ischemia) or donation after circulatory death groups with 60 or 90 min of warm ischemia (n = 5, each). Thermal images of the lower lobes were continuously collected from the bottom of an organ chamber using infrared thermography throughout EVLP.At 8 min, lung surface temperatures of nonsuitable cases were significantly lower than in suitable cases (25.1 ± 0.6 vs. 27.8 ± 1.2°C, p 0.001), while there was no difference in lung surface temperatures between the two groups at 0-4 min and 12-120 min. There was a significant negative correlation between lung surface temperatures at 8 min and wet/dry ratio at 2 h in the lower lobes (R = -0.769, p 0.001, cutoff = 26°C, area under the curve = 1.0). A lung surface temperature of26°C was significantly correlated with poor pulmonary function and transplant nonsuitability.A lung surface temperature of ≥26°C at 8 min is a good early predictor of transplant suitability in cellular EVLP and might be applicable in clinical EVLP.

This study aimed to evaluate the outcomes of our repair technique using autologous pericardial patches for active infective endocarditis with extensive mitral valve destruction.From 2009 through 2016, 12 patients with extensive mitral leaflet destruction due to infective endocarditis underwent mitral valve repair with an autologous pericardial patch. Mid-term clinical outcomes and echocardiographic findings of these patients were retrospectively assessed.The perioperative mortality rate was 8.3% (1/12). Postoperatively, the mitral regurgitation grade was ≤ 1 + in all patients. During 5.0 ± 3.2 years of follow-up, there was no recurrence of infective endocarditis or death. There were no cases of mitral regurgitation grade + 1 and pressure gradient 5 mmHg during follow-up among 6 patients who underwent posterior leaflet reconstruction, whereas elevation of the pressure gradient was observed in patients who underwent reconstruction of two areas of the anterior leaflet and survived up till the follow-up phase among 3 patients who underwent anterior leaflet repair. The mitral regurgitation grade worsened and pressure gradient was elevated during the follow-up phase in the 2 patients who underwent bi-leaflet repair, and reoperation was performed.Mitral valve reconstruction using autologous pericardial patch is a useful treatment option for extensive mitral valve destruction due to active infective endocarditis. Our clinical data revealed that good mid-term results were obtained for posterior leaflet lesions, while extensive anterior leaflet and bi-leaflet lesion repair did not yield satisfactory results. The indication for surgical repair should be carefully evaluated when an extensive anterior region is involved.

Saphenous vein graft (SVG) is the most commonly used conduits in coronary artery bypass grafting (CABG), but the disadvantage of SVG is its tendency for progressive failure. We hypothesized that therapeutic-dose warfarin (international normalized ratio [INR]1.6) plus aspirin improve SVG patency. This study aimed to evaluate the factors contributing to SVG patency.Since 2010-2020, 199 patients who underwent isolated CABG using SVG were divided into two groups according to their INR values in the first year: group T (INR1.6) and group L (INR1.6).Group T had 162 SVGs (105 patients) and group L had 151 SVGs (94 patients). The 1-, 4-, and 7-year SVG patency rates were higher in group T than in group L (99%, 96%, and 92% vs. 93%, 86%, and 79%, respectively; p = 0.00378). The 1-, 4-, and 7-year freedom from repeat-revascularization was higher in group T than in group L (100%, 100%, and 99% vs. 98%, 95%, and 87%, respectively; p = 0.0264). Multivariate analysis showed that therapeutic-dose warfarin (p = 0.00204) and target vessel diameter (p0.0001) were independent risk factors of SVG occlusion.Therapeutic-dose warfarin (INR1.6) plus aspirin after CABG improved the long-term patency of SVG and decreased repeat-revascularization rate.

Purpose Hybrid aortic arch repair (HAR) has been implemented for extended aortic arch and descending thoracic aortic disease since 2012 in our institution. This study aimed to estimate the early and mid-term efficacy and safety of HAR. Materials and Methods From 2007 to 2019, 56 patients underwent HAR for extended aortic arch disease, and 75 patients underwent total arch replacement (TAR) for arch-limited disease. HAR comprises 3 procedures: replacement of the aorta, reconstruction of all arch vessels, and thoracic endovascular aortic repair (TEVAR) from zone 0 to the descending aorta after cardiopulmonary bypass is off in 1 stage. The type II-1 HAR procedure, in which the ascending aorta and aortic arch distal to the brachiocephalic artery are replaced, was the most frequently selected procedure (40/56 patients). The outcomes of the type II-1 HAR procedure were compared with those of TAR using the Cox regression analysis. Results The median follow-up period was 36 months. In HAR, the operative mortality, in-hospital mortality, and postoperative permanent neurological deficits were not observed. The paraplegia rate was 1.8%. TEVAR-related complications occurred in 3 patients. Among the patients with non-ruptured atherosclerotic aortic arch aneurysm (31 type II-1 HAR patients and 36 TAR patients, the postoperative respiratory support time in those who underwent type II-1 HAR was quicker than in those who underwent TAR (pConclusions HAR, especially the type II-1 procedure, can treat extended aortic arch disease with acceptable survival outcomes. The development of TEVAR technology will further improve the outcomes of HAR in the future.

Purpose: The principal of this analysis was to understand global feature of the number and type of grafts and number of diseased vessels of those undergoing coronary artery bypass grafting (CABG) and their short-term clinical results. Methods and Results: This report presents annual report on the collective data of CABG in the year 2018 (1 January–31 December). Data were collected based on the series of questionnaire which has been performed by The Japanese Association for Coronary Artery Surgery (JACAS), capturing the corresponding data from the Japan Adult Cardiovascular Surgery Database (JCVSD). We also analyzed descriptive clinical results of those undergoing surgeries for acute myocardial infarction and ischemic mitral regurgitation. Conclusion: This is the first article summarizing the results from annually performed questionnaires by JACAS based on JCVSD, on the trend of CABG procedures and clinical results in Japan as a scientific manuscript.

Antithrombogenicity of extracorporeal membrane oxygenation (ECMO) devices, particularly oxygenators, is a current problem, with numerous studies and developments underway. However, there has been limited progress in developing methods to accurately compare the antithrombogenicity of oxygenators. Animal experiments are commonly conducted to evaluate the antithrombogenicity of devices; however, it is challenging to maintain a steady experimental environment. We propose an innovative experimental animal model to evaluate different devices in a constant experimental environment in real-time.This model uses two venous-arterial ECMO circuits attached to one animal (one by jugular vein and carotid artery, one by femoral vein and artery) and real-time assessment of thrombus formation in the oxygenator by indocyanine green (ICG) fluorescence imaging. Comparison studies were conducted using three pigs: one to compare different oxygenators (MERA vs. CAPIOX) (Case 1), and two to compare antithrombotic properties of the oxygenator (QUADROX) when used under different hydrodynamic conditions (continuous flow vs. pulsatile flow) (Cases 2 and 3).Thrombi, visualized using ICG imaging, appeared as black dots on a white background in each oxygenator. In Case 1, differences in the site of thrombus formation and rate of thrombus growth were observed in real-time in two oxygenators. In Case 2 and 3, the thrombus region was smaller in pulsatile than in continuous conditions.We devised an innovative experimental animal model for comparison of antithrombogenicity in ECMO circuits. This model enabled simultaneous evaluation of two different ECMO circuits under the same biological conditions and reduced the number of sacrificed experimental animals.

Extracorporeal membrane oxygenation (ECMO) plays an important role in the coronavirus disease 2019 (COVID-19) pandemic. Management of thrombi in ECMO is generally an important issue; especially in ECMO for COVID-19 patients who are prone to thrombus formation, the thrombus formation in oxygenators is an unresolved issue, and it is very difficult to deal with. To prevent thromboembolic complications, it is necessary to develop a method for early thrombus detection. We developed a novel method for detailed real-time observation of thrombi formed in oxygenators using indocyanine green (ICG) fluorescence imaging. The purpose of this study was to verify the efficacy of this novel method through animal experiments. The experiments were performed three times using three pigs equipped with veno-arterial ECMO comprising a centrifugal pump (CAPIOX SL) and an oxygenator (QUADROX). To create thrombogenic conditions, the pump flow rate was set at 1 L/min without anticoagulation. The diluted ICG (0.025 mg/mL) was intravenously administered at a dose of 10 mL once an hour. A single dose of ICG was 0.25mg. The oxygenator was observed with both an optical detector (PDE-neo) and the naked eye every hour after measurement initiation for a total of 8 hours. With this dose of ICG, we could observe it by fluorescence imaging for about 15 minutes. Under ICG imaging, the inside of the oxygenator was observed as a white area. A black dot suspected to be the thrombus appeared 6-8 hours after measurement initiation. The thrombus and the black dot on ICG imaging were finely matched in terms of morphology. Thus, we succeeded in real-time thrombus detection in an oxygenator using ICG imaging. The combined use of ICG imaging and conventional routine screening tests could compensate for each other's weaknesses and significantly improve the safety of ECMO.

The objective of this study is to investigate the effect of preoperative diabetes on all-cause mortality and major postoperative complications among patients with continuous-flow left ventricular assist device (LVAD) by using data from a national database.Methods and Results: The 545 study patients who underwent primary HeartMateII implantation between 2013 and 2019 were divided into 2 groups according to their diabetes mellitus (DM) status; patients with DM (n=116) and patients without DM (n=429). First, the on-device survival and incidence of adverse events were evaluated. Second, after adjusting for patients' backgrounds, the change of laboratory data in the 2 groups were compared. Overall, on-device survival at 1, 2, and 3 years was almost equivalent between the 2 groups; it was 95%, 94%, and 91% in patients without DM, and 93%, 91%m and 91% in patients with DM (P=0.468) The incidence of adverse events was similar between 2 groups of patients, except for driveline exit site infection in the adjusted cohort. Cox proportional hazards regression analysis revealed younger age (HR: 0.98 (95% confidence interval (CI): 0.97-0.99, P=0.001) and presence of DM (HR: 1.83 (95% CI: 1.14-2.88), P=0.016) as significant predictors of driveline infection. Laboratory findings revealed no differences between groups throughout the periods.The clinical results after LVAD implantation in DM patients were comparable with those in non-DM patients, except for the driveline exit site infection.

OBJECTIVES This study aimed to evaluate the outcomes of the patients who underwent restrictive annuloplasty (RA) plus papillary muscle relocation anteriorly (PMR-A) with the risk factors in mitral valve repair for functional mitral regurgitation (FMR). METHODS Eighty-six patients underwent mitral valve repair with RA for FMR. Thirty-five of them received additional bilateral papillary muscle relocation for severe leaflet tethering. The papillary muscles were relocated posteriorly (PMR-P) early in the study. Then, in the later period, the technique was modified to PMR-A, in which the papillary muscles were relocated anteriorly for 24 cases. The survival of the patients undergoing RA + PMR-A was examined retrospectively, adjusting for differences in patient background. RESULTS Twenty-three deaths were observed during the follow-up period out of the 86 cases. Independent preoperative risk factors for survival were left ventricular ejection fraction, patient age and B-type natriuretic peptide (BNP) level. Among the patients with BNP CONCLUSIONS Long-term survival for patients who underwent RA plus bilateral PMR-A was promising. Patients with significantly higher BNP had lower survival after valve repair for FMR.

Fractured tracheostomy tube is a rare, late complication. It typically occurs at the junction of metallic tube. We report an atypical case with laceration of the main trunk of a silastic tube after short period of use (10 days).

Pump thrombosis induces significant complications and requires timely detection. We proposed real-time monitoring of pump thrombus in a magnetically levitated centrifugal blood pump (mag-lev pump) without using additional sensors, by focusing on the changes in the displacement of the pump impeller. The phase difference between the current and displacement of the impeller increases with pump thrombus. This thrombus detection method was previously evaluated through simulated circuit experiments using porcine blood. Evaluation of real-time thrombus detection in a mag-lev blood pump was performed using a porcine left ventricular assist circulation model in this study. Acute animal experiments were performed five times using five Japanese domestic pigs. To create thrombogenic conditions, fibrinogen coating that induces thrombus formation in a short time was applied to the inner surfaces of the pump. An inflow and an outflow cannula were inserted into the apex of the left ventricle and the carotid artery, respectively, by a minimally invasive surgical procedure that allowed minimal bleeding and hypothermia. Pump flow was maintained at 1 L/min without anticoagulation. The vibrational frequency of the impeller (70 Hz) and its vibrational amplitude (30 μm) were kept constant. The thrombus was detected based on the fact that the phase difference between the impeller displacement and input current to the magnetic bearing increases when a thrombus is formed inside a pump. The experiment was terminated when the phase difference increased by over 1° from the lowest value or when the phase difference was at the lowest value 12 hours after commencing measurements. The phase difference increased by over 1° in three cases. The pump was stopped after 12 hours in two cases. Pump thrombi were found in the pump in three cases in which the phase difference increased by over 1°. No pump thrombus was found in the other two cases in which the phase difference did not increase. We succeeded in real-time thrombus monitoring of a mag-lev pump in acute animal experiments.

The aims of the present study were to establish a population pharmacokinetic (PPK) model of cefazolin for adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) and to assess the probability of target attainment (PTA) for the prophylaxis of surgical site infection (SSI) using cefazolin. Adult patients who underwent cardiac surgery with CPB were enrolled in the prospective study. Blood samples for plasma cefazolin assay were collected, and total and unbound drug concentrations were measured and analysed using the nonlinear mixed-effects modelling (NONMEM) software considering saturable plasma protein binding. Using the PPK model, plasma unbound cefazolin concentration-time courses with current prophylaxis protocols were simulated, and the PTA for common SSI pathogens was estimated. A total of 199 blood samples were obtained from 27 patients. A one-compartment model with first-order elimination plus an on/off CPB compartment best described the data. The population mean for systemic drug clearance (CL) was reduced and that for the volume of distribution (V) was increased during CPB compared with the pre-CPB values. CPB-induced hypoalbuminemia was associated with reduced maximum protein binding (Bmax). The simulation studies suggested that the current dosing protocols are insufficient for attaining PTA > 0.9 throughout surgery against pathogens with minimum inhibitory concentrations (MICs) >8 mg/L. A new dosing protocol that achieves a PTA > 0.9 for pathogens with a MIC of 16 mg/L was proposed. PPK modelling with simulation may be valuable for devising a cefazolin prophylaxis protocol for patients undergoing cardiac surgery with CPB.

Takayasu arteritis (TA) occasionally involves the coronary ostium leading to myocardial ischemia. Although surgical coronary ostial angioplasty is desirable for ostial stenosis, the patch materials and long-term results are controversial. We used femoral artery (FA) as a patch material for coronary ostial angioplasty in 3 TA patients. Coronary ostial enlargement with a longitudinal incision followed by rectangular FA patch augmentation was performed to extend the narrowing coronary ostium. In all patients, coronary ostial stenosis was successfully repaired. Ostial angioplasty using an FA patch would be a reasonable surgical strategy to treat coronary ostial stenosis in TA.

Purpose We developed a heart positioner, the Tentacles NEO, specifically designed for minimally invasive coronary artery bypass grafting (MICS-CABG). Description The device has 3 flexible suction tubes, with a suction cup at the tip of each tube. The suction tubes can be detached from the device body, allowing them to be manipulated in any direction through a small incision around the small thoracotomy. When the device displaces the heart, the suction cup moves behind the chest wall and does not crowd the operative field. Evaluation Although the sideways suction force of the new device was as strong as that of the original device, Tentacles, the longitudinal and perpendicular force exerted was approximately 80% of the original device. Nevertheless, the new device could safely and favorably displace the heart in a pig model and even during off-pump CABG via sternotomy. During MICS-CABG, the device was able to displace the heart without crowding the operative field. Conclusions The new heart positioner, Tentacles NEO, is a useful and practical heart positioner suitable for MICS-CABG.

OBJECTIVES The goal of this study was to evaluate the outcomes of patients with subvalvular procedures for functional tricuspid regurgitation (TR) with severe leaflet tethering. METHODS Of 175 patients who had tricuspid valve surgery between June 2016 and June 2021, a total of 17 patients with functional TR with a preoperative tethering height ≥8 mm underwent subvalvular procedures (annular repositioning [An-Rep]) to reduce septal leaflet tethering, papillary muscle relocation to reduce anterior leaflet tethering, and/or papillary muscle bundling [PMB] to reduce anterior and posterior leaflet tethering along with ring annuloplasty at our institution. A single subvalvular procedure was performed in 9 patients (An-Rep in 5 patients, PMB in 4 patients; group S), and a combination of subvalvular procedures was performed in 8 patients (An-Rep and papillary muscle relocation in 5 patients, An-Rep and PMB in 3 patients; group C). RESULTS Predischarge TR grades and tethering height were significantly improved (3.2 ± 1.3–1.0 ± 0.5, p = 0.001; 9.9 ± 2.5 mm–5.5 ± 2.8 mm, p < 0.001, respectively). An-Rep and PMB significantly reduced the postoperative closing angles of the septal and anterior leaflets, respectively. During the 20.4 ± 19.5-month follow-up period, the rates of freedom from death and moderate TR at 2 years were 41.7% in group S, and 71.4% in group C (p = 0.39), respectively. In group C, TR recurrence was not observed at 2 years postoperatively. CONCLUSIONS Subvalvular procedures were effective in reducing the predischarge TR grades and tethering height. The combination of subvalvular procedures might be a durable strategy to prevent recurrent TR.

Although the magnetically levitated centrifugal blood pump (mag-lev pump) is considered superior to other pumps in antithrombogenicity, thrombotic complications are still reported. Research into thrombus detection inside a mag-lev pump is very important for solving this problem. Our research group has already proposed a method to detect a thrombus inside a mag-lev pump in real time without an additional sensor, which is named the impeller vibration method. To efficiently advance our research with reproducibility, a preconditioning method to induce thrombus inside the pump was thought to be necessary. Therefore, this study aimed to develop a preconditioning method that induces thrombus formation. To verify this method, in vitro experiments for thrombus detection were performed. A mag-lev pump developed at Tokyo Institute of Technology was used. A fibrinogen solution was coated on the inner surfaces of the bottom housing to induce thrombus formation at the target point inside the pump. The thrombus is detected by utilizing the phenomenon that the phase difference between the impeller displacement and input current to the magnetic bearing increases when a thrombus is formed inside a pump. Five hundred mL of porcine blood anticoagulated with heparin sodium was circulated in the mock circuit, and protamine sulfate was administered. Flow rate (1 L/min), impeller vibrational frequency (70 Hz), and vibrational amplitude (30 µm) were set to constant. The experiment was terminated when the phase difference increased by over 2° from the minimum value. The experiments were performed in fibrinogen-coated (group F, n = 5) and non-coated pumps (group N, n = 5). In group F, thrombus formation was observed at the fibrinogen-coated point of the housing. In contrast, a relatively small thrombus was observed in varying locations such as the housing or the impeller in group N. Thrombus formation time (the time from when the phase difference takes the minimum value to when the experiment is terminated) was different between the two groups. The mean time was significantly shorter in group F (44 ± 29 minutes) than in group N (143 ± 38 minutes; p = 0.0019). Therefore, a preconditioning method that induced thrombus formation at the target point inside a blood pump was successfully developed.

Purpose To stabilize the sternum after median sternotomy, unsintered hydroxyapatite poly-L-lactide (u-HA/PLLA) sternal pins are frequently used in Japan. However, sternal pins are ineffective in the fragile bone marrow. Thus, a corrugated sheet made of u-HA/PLLA was developed as a new sternal fixation device. Methods To examine the effects of the device, we measured the shear force using a sternal model and cadaver. The shear force of the corrugated sheet, sternal pin, and simple wire was compared. The device size was determined after reviewing the sternal computed tomography (CT) of 128 patients. Results The shear force of the model with the corrugated sheet (286 [256-295] N) was higher than that with sternal pins (135 [134-139] N, p = 0.03) and simple wire (94 [90-104] N, p = 0.03) at 2-mm displacement. In the cadaver test, the shear force of the sternal halves with the device was about two times higher than that without the device. Retrospective CT showed that 18-mm wide device applies to 99% male and 87% female patients at the fourth intercostal level. Conclusion The corrugated sheet might provide a stronger fixation effect in the fragile bone marrow. The device width was modified to 18 mm to be applicable for most Japanese patients.

A conventional arteriovenous graft in patients on dialysis often leads to anastomotic stenosis, which decreases the blood flow rate and increases the risk of complications. In this study, based on hydrodynamics, the pulsatile pressure at the blood vessel graft-vein junction was investigated experimentally and numerically for revealing the causes of stenosis formation and inward remodeling. In the experiments, the pulsatile pressure and displacement at the anastomotic connection were measured at a branched collapsible tube. It was revealed that the pressure becomes negative between pressure peaks of the pulsatile flow; furthermore, tube diameter changes in accordance with the pressure pulsation. Subsequently, numerical simulations revealed that a relatively large pressure difference occurs at the anastomotic connection because of flow collision and separation as compared with the other part, and the pulsatile pressure. Therefore, it is possible that vein at an anastomotic connection may change its shape under pulsating flow. Furthermore, it was found that the pressure difference slightly increased with the anastomosis angle, but the anastomosis angle did not affect the flow rate. Clinical trials in the next step are required to reveal the causal relationship between stenosis and the pulsatile pressure, but the pulsatile flow and its pressure are likely to be one factor in stenosis and inward remodeling.

Tracheobronchial aspergillosis is a rare but lethal disease with characteristic findings of tracheal plaques and ulcers. It requires appropriate airway management for possible tracheal obstruction with the black mucus plug.

Ex vivo lung perfusion (EVLP) is an emerging tool to evaluate marginal lungs in lung transplantation. However, there is no objective metric to monitor lobular regional oxygenation during EVLP. In this study, we developed oxygen saturation (SaO2) imaging to quantitatively assess the regional gas exchange potential of the lower lobes. Ten porcine lungs were randomly divided into control and donation after circulatory death (DCD) groups (n = 5, each). Lungs were perfused in cellular EVLP for 2 h, and multispectral images were continuously collected from the dorsal sides of the lower lobes. We examined whether lower lobe SaO2 correlated with PaO2/FiO2 (P/F) ratios in lower pulmonary veins (PV). The wet/dry ratio in lower lobes was measured and Monte Carlo simulations were performed to investigate the method’s feasibility. There was a significant correlation between lower lobe SaO2 and the P/F ratio in lower PV (r = 0.855, P 2 and higher wet/dry ratio than the control group (P 2 was limited according to Monte Carlo simulations. The developed technology provides a noninvasive and regional evaluative tool of quantitative lobular function in EVLP.

OBJECTIVES There are few reports on the rotational position of the aortic valve relative to the base of the left ventricle, and its influence on valve-sparing aortic root replacement (VSRR) has not been reported. Based on our experience with complications such as right atrial perforation and tricuspid valve injury, we investigated the cause of these complications in terms of morphological variations in the aortic root and its surrounding structures. METHODS The aortic valve rotation relative to the base of the left ventricle was assessed in 30 patients with tri-leaflet aortic valves who underwent VSRR. The influence of such anatomical variations on surgical procedures was investigated. RESULTS The aortic valve was positioned normally in 25 patients (83.3%), rotated counterclockwise in 4 (13.3%), and rotated clockwise in 1 patient (3.3%). In patients with a counterclockwise rotated aortic valve, the non-coronary sinus was the largest compared with other sinuses. This aortic valve rotation could be diagnosed by multidetector row computed tomography. In all patients who had difficulty in the external dissection of the right sinus of Valsalva, the aortic valve was counterclockwise rotated and forcible dissection had a risk of right atrial perforation and tricuspid valve injury. CONCLUSIONS Aortic valve rotation is an element that complicates VSRR. The rotational position of the aortic valve can be diagnosed preoperatively using multidetector row computed tomography and understanding the anatomy of the aortic valve related to rotational position help decide proper surgical decision-making in performing aortic root reconstruction procedure.

Objective Mitral subvalvular procedures in addition to restrictive annuloplasty are promising for ischemic mitral regurgitation (IMR). However, the prevalence and efficacy of specific subvalvular repair in severe IMR have not been elucidated. This is the first nationwide survey regarding surgeons' attitudes toward IMR in Japan. Methods A questionnaire was sent to 543 institutions. From 2015 to 2019, numbers of elective first-time mitral valve replacement (MVR) with/without complete chordal preservation (CCP)/papillary muscle approximation (PMA) and mitral valvuloplasty (MVP) with/without papillary muscle relocation (PMR)/PMA in patients with severe IMR were collected. Concomitant procedures for coronary artery, tricuspid valve, and arrhythmia could be included but left ventricular reconstruction was excluded. Results Completed questionnaires were received from 286 institutions (52.7%). The majority (90%) had less than 20 cases within 5 years. The number of MVP (1413, 61.5%) surpassed MVR (886, 38.5%). CCP was performed in half of MVR (50.0%), while PMA was included in only 1.9% of MVR. PMA and PMR were also performed infrequently, in only 7.7% and 10.9% of MVP, respectively. Conclusion Japanese surgeons aggressively perform MVP for severe IMR. Subvalvular repair was also aggressively performed in addition to MVR, but not to MVP. A multicenter registry study is in progress.

Proper positioning of the heart through a small left thoracotomy is the main challenge during off-pump minimally invasive cardiac coronary artery bypass grafting. Here we report a novel technique for target vessel exposure using the Tentacles NEO (Sumitomo Bakelite, Co Ltd, Tokyo, Japan) multisuction heart positioner, a device with 3 independent small suction cups that can be applied to various surfaces of the heart and pulled toward any direction using attached traction cords. The armless design of the device enables the use of flexible exposure techniques and contributes to the safety and feasibility of minimally invasive coronary artery bypass grafting.

Pediatric thoracic aortic aneurysms are very rare, and almost all patients with such aneurysms have inflammatory or connective tissue diseases. This report describes a case involving 10-year-old girl who had an aortic arch and descending thoracic aortic aneurysm. Preoperative fluorine-18-fluorodeoxyglucose positron emission tomography combined with computed tomography showed an inflammatory lesion corresponding to the aneurysm's location. The ascending aorta, aortic arch, and descending thoracic aorta were replaced through median sternotomy and left thoracotomy with safe systemic and brain perfusion to avoid placing the anastomoses within the inflammatory lesion. The patient was discharged without complications, and an SMAD3 mutation was detected by postoperative mutational screening.

Hemocompatibility-related adverse events (HRAEs) are substantial issues in patients with left ventricular assist devices (LVADs). Atrial fibrillation (AF) is associated with worse prognosis in patients with heart failure (HF), but its effect on HRAEs following LVAD implantation remain uncertain.Methods and Results:Data from the Japanese Mechanically Assisted Circulatory Support registry of consecutive patients who received HeartMate II LVADs and were followed for 1 year were retrospectively reviewed. Among 190 patients, 23 had AF and 167 had sinus rhythm. The AF group had comparable baseline characteristics with the non-AF group except for their higher age (53 vs. 42 years, P0.001). Following LVAD implantation, most cases of AF (73%) persisted. Antiplatelet therapy, anticoagulation therapy, and LVAD speed following LVAD implantation were comparable between groups (P0.05 for all). The 1-year survival free from HRAEs was comparable between groups (83% vs. 76%, P=0.52). Event rates of the breakdown of HRAEs were comparable between groups except for a relatively higher rate of surgically managed pump thrombosis in the AF group (0.16 vs. 0.04, incidence rate ratio 3.75, 95% confidence interval 0.87-16.1, P=0.075). These trends still remained with propensity score-matched comparison.Existence of AF had no effect on the development of HRAEs following LVAD implantation. The need to aggressively treat AF before or after LVAD implantation needs further investigation.

Veno-venous extracorporeal membrane oxygenation (VV ECMO) is an effective and proven adjunct support for various severe respiratory failures requiring invasive mechanical ventilation and cardiovascular support. In response to the rapidly increasing number of COVID-19 patients in Japan, we launched an ECMO support team comprised of multidisciplinary experts including physicians, nurses, perfusionists, and bioethicists in preparation for the threat of a pandemic. From April 2 to July 15, 2020, Tokyo Medical and Dental University hospital treated 104 PCR confirmed COVID-19 patients. Among those, 34 patients were admitted to intensive care unit (ICU) and 5 patients required VV ECMO. All management related to ECMO was decided by the ECMO support team in addition to participation of the ECMO support team in daily multidisciplinary rounds in the ICU. Median age was 54 years old. Duration from onset to mechanical ventilation (MV) and MV to ECMO were 8 and 7 days, respectively. Four patients (80%) were successfully weaned off from ECMO. One patient died after 81 days of ECMO run. Four patients were discharged and recovered to their prehospital quality of life without major disability. We achieved a high survival rate using ECMO in our low volume ECMO institution during the COVID-19 pandemic. Multidisciplinary decision-making and a team approach for the unclear pathology with an emerging infectious disease was effective and contributed to the survival rate.

Background There are few agents that have been proven effective for COVID-19. Predicting clinical improvement as well as mortality or severity is very important. Objectives This study aimed to investigate the factors associated with the clinical improvement of COVID-19. Methods Overall, 74 patients receiving treatment for COVID-19 at Tokyo Medical and Dental University Hospital from April 6th to May 15th, 2020 were included in this study. Clinical improvement was evaluated, which defined as the decline of two levels on a six-point ordinal scale of clinical status or discharge alive from the hospital within 28 days after admission. The clinical courses were particularly investigated and the factors related to time to clinical improvement were analyzed with the log-rank test and the Cox proportional hazard model. Results Forty-nine patients required oxygen support during hospitalization, 22 patients required invasive mechanical ventilation, and 5 patients required extracorporeal membrane oxygenation. A total of 83% of cases reached clinical improvement. Longer period of time from onset to admission (≥10 days) (HR, 1.057; 95% CI, 1.002–1.114), no hypertension (HR, 2.077; 95% CI, 1.006–4.287), and low D-dimer levels (

The combination of extracorporeal membrane oxygenation with lung‐protective ventilation strategies could be a potential treatment option for intractable pneumothorax with coronavirus disease 2019 (COVID‐19) to avoid unnecessary surgical procedures and aerosol generation., Background Some patients with coronavirus disease 2019 (COVID‐19) develop pneumothorax. Tube thoracotomy and bulla resection could generate aerosols and cause virus transmission; the optimal treatment strategy remains unclear. Case Presentation A 57‐year‐old male was transferred as a severe COVID‐19 pneumonia case. On the 16th day after admission, the patient’s respiratory condition deteriorated, and the chest X‐ray revealed the presence of severe right‐sided pneumothorax. A chest drain was immediately inserted; however, a significant air leak continued, and severe ventilator settings were required. Thus, veno‐venous extracorporeal membrane oxygenation (VV‐ECMO) treatment was initiated to allow the lungs to rest. After 10 days of lung‐protective ventilation, the patient was weaned from ECMO and the chest drain was removed on the following day with no major comorbidities. Conclusion The combination of ECMO with lung rest strategy could be a treatment option for intractable pneumothorax with COVID‐19 to avoid unnecessary surgical procedures and aerosol generation.

Background The bridge-to-bridge (BTB) strategy, a conversion to durable left ventricular assist device (LVAD) after stabilization using surgical temporary mechanical circulatory supports for a couple of months, is not uncommon in Japan. However, its effect on clinical outcomes in comparison with a primary durable LVAD implantation strategy remains unknown.Methods and Results:Data of 837 consecutive patients (median age 45, 73% males) who underwent durable LVAD implantation as BTB (n=168) or primary implant (n=669) between April 2011 and April 2019 were retrospectively reviewed from the prospective multicenter Japanese mechanically assisted circulatory support registry. The BTB group was younger and had comparable end-organ function, better hemodynamic profile, and longer operative time compared with the primary implant group at baseline. The 3-year survival was 80% vs. 87% (P=0.007) for the BTB and primary implant groups respectively, with greater observed rates of stroke and infection as the predominant causes of death. The BTB strategy was independently associated with increased 3-year mortality (hazard ratio 2.69 [1.43-5.07], P=0.002) in addition to other significant risk factors. Conclusions The BTB cohort had comparable baseline characteristics to the primary implant cohort at the time of durable LVAD conversion, but had lower 3-year survival. Detailed analysis clarifying the causality of this finding should improve outcomes with the BTB strategy.

Arteritis is an inflammatory disease of the vessel walls, resulting in vascular damage and a wide variety of clinical symptoms and multisystem disorders. Because aneurysmal disease, coronary disease, and aortic insufficiency affect patient prognosis, surgical intervention plays an important role. Preoperatively, systemic vessels, cardiac function, and other major organs should be evaluated. Regarding the surgical technique, reinforcement of the anastomosis to the fragile aortic wall is important to prevent pseudoaneurysmal formation and prosthetic valvular detachment. As aortic root replacement, we have been applying the modified Bentall procedure with a "double fixation technique" and obtained desirable outcomes. Although endovascular repair for aneurysmal disease is one of the treatment options, its longterm efficacy remains uncertain. Postoperative control of inflammation with corticosteroids and/or immunosuppressive agents is also important for long-term management. Pseudoaneurysmal formation and prosthetic valvular detachment may occur progressively over a long period of time. To prevent these complications, strict follow-up with imaging and inflammation control should be performed.