Pump Exchange from a Left Ventricular Assist Device to a Jarvik 2000 with a Postauricular Cable Due to Abdominal Driveline Infection.

Driveline infection in patients with implantable left ventricular assist devices (LVAD) remains common and crucial. Once a driveline exit-site infection reaches the LVAD component, radical treatment such as LVAD exchange may become necessary, although the clinical results are unsatisfactory. The Jarvik 2000 device, which utilizes a postauricular cable, allows the driveline to exit the body behind the ear (postauricular) instead of through an abdominal site. Here, we report the case of a patient who had awaited heart transplantation for more than 6 years and had a critical driveline infection that almost reached the LVAD pump. The patient underwent a pump exchange using the Jarvik 2000 with a postauricular cable, with excellent results. It is a useful replacement option for patients with abdominal driveline infections, owing to its small pump pocket and the availability of an alternative pathway for the driveline.

Role of Aggressive Aneurysm Sac Embolization Before Endovascular Abdominal Aneurysm Repair in Preventing Type II Endoleak and Sac Expansion.

Background: This study aimed to evaluate the effect of aggressive embolization of side branches arising from the aneurysmal sac before endovascular aneurysm repair. Methods: This retrospective study included 95 patients who underwent endovascular infrarenal abdominal aortic aneurysm repair at Tottori University Hospital between October 2016 and January 2021. Of these, 54 underwent standard endovascular aneurysm repair (conventional group), and 41 underwent coiling of the inferior mesenteric and lumbar arteries before undergoing endovascular aneurysm repair (embolization group). The occurrence of type II endoleak, change in aneurysmal sac diameter, and reintervention rate due to type II endoleak during follow-up were evaluated. Results: Compared to the conventional group, the embolization group had a significantly lower incidence of type II endoleak, more frequent aneurysmal sac shrinkage, and lower aneurysmal sac growth related to type II endoleak. Conclusion: Our results demonstrated the effectiveness of aggressive aneurysmal sac embolization before endovascular aneurysm repair to prevent type II endoleak and the consequent long-term aneurysmal sac enlargement.

Robot-Assisted Aortic Valve Replacement　- First Clinical Report in Japan.

BACKGROUND: Robot-assisted valve surgery represents the latest development in the field of minimally invasive approaches. Robotic assistance may provide greater visualization, enhanced dexterity, and greater precision than traditional mini-thoracotomy aortic valve replacement.Methods and Results: Aortic valve replacement operations using the da Vinci Xi Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA) were performed on 2 patients, 1 with severe aortic insufficiency and the other with aortic stenosis. Both patients had an uneventful postoperative course and were discharged without any adverse events. CONCLUSIONS: Robot-assisted assisted aortic valve replacement appears feasible and safe in limited cases.

Safe launch of a robotically assisted mitral valve repair program in a single center: experience of initial 20 cases under the Center for Minimally Invasive Surgery.

Robotically assisted mitral valve repair was approved by the Japanese government in April 2018. However, understanding robotic surgery involves steep learning curves of surgeons and dedicated cardiac teams. The Center for Minimally Invasive Surgery (CMIS) of Tottori University Hospital is a multidisciplinary organization established in 2011 with seven surgical departments. In this study, we report strategies for improving the safety of robotic surgery in the CMIS and early results of robotic mitral valve repair at our hospital. We reviewed the first 20 patients who underwent robotic primary mitral valve repair, including concomitant procedures, from October 2019 to September 2021 under the supervision of the CMIS. Before starting the program, the CMIS requires setting console time limit to 180 min and implementing risk management strategies through simulation training for various mechanical failures. Mitral valve repair was completed in all patients. There was no in-hospital or 30-day mortality. No conversion to median sternotomy was necessary. The analysis of mitral pathology revealed 1 case of functional mitral regurgitation, 12 cases of posterior lesions, 3 cases of anterior lesions, 3 cases of bileaflet lesions, and 1 case of commissural lesion. The average cross-clamp time was 133 ± 27 min. Sixteen cases had trace mitral regurgitation postoperatively, and 4 cases had mild mitral regurgitation. The median (interquartile range) postoperative hospital stay was 10 (8.5-12.5) days. Robotically assisted mitral valve repair was performed safely with assistance from the multidisciplinary CMIS, and the early results were satisfactory without compromising clinical outcomes.

Impact of frailty on early and mid-term outcomes of hybrid aortic arch repair.

PURPOSE: The purpose of this study was to investigate the impact of frailty on the clinical outcomes of hybrid aortic arch repair with debranching of the supra-aortic arteries. METHODS: Consecutive patients ≥ 75 years old who underwent hybrid aortic arch repair from January 2010 to December 2019 were retrospectively analyzed. Using the Canadian Study of Health and Aging (CSHA) scale, all patients with a CSHA scale score > 4 were defined as frail. The frail patients (FP) group and the non-frail patients (NFP) group were compared regarding the early and mid-term outcomes of hybrid aortic arch repair. RESULTS: A total of 84 patients were included. The early postoperative results were not markedly different between the groups, except that the rate of transfer to a rehabilitation hospital was higher in the FP group than in the NFP group. The survival at 5 years was significantly lower in the FP group at 43.0% than in the NFP group at 67.7% (P = 0.015). However, the freedom from aorta-related death was not significantly different between the two groups. CONCLUSION: Frailty did not affect the short-term outcomes of hybrid aortic arch repair; however, the mid-term outcomes, including the survival, of the frail patients were significantly worse than those of the non-frail patients, mostly because of non-aorta-related causes.

Cost analysis of transcatheter versus surgical aortic valve replacement in octogenarians: analysis from a single Japanese center.

Transcatheter aortic valve replacement (TAVR) has revolutionized the prognosis of intermediate- or high-risk patients with severe aortic stenosis, particularly among older adults. However, in possible candidates for surgical aortic valve replacement (SAVR), the implantation of expensive prostheses may be questionable in an era when healthcare costs are becoming a major concern. In this retrospective analysis of a single Japanese center, we focused on patients aged over 80 years; the objectives of this study were: (1) to compare TAVR and SAVR in terms of total hospitalization costs and (2) to describe the itemized cost of TAVR and SAVR to identify patients aged over 80 years in whom TAVR or SAVR would be cost-effective. A total of 146 patients aged over 80 years who underwent TAVR or SAVR for severe aortic stenosis were included. These patients were divided into a high-risk group (Society of Thoracic Surgeons [STS] mortality score > 8%; 36: TAVR and 12: SAVR) with 48 patients and a non-high-risk group (STS mortality score < 8%; 45: TAVR and 53 SAVR) with 98 patients. No 30-day mortality was observed in either group. In both groups, postoperative intensive care unit stay and hospital stay were longer with SAVR than with TAVR. In the non-high-risk group, the total cost was comparable for TAVR and SAVR; however, in the high-risk group, the total cost was significantly higher with SAVR than that with TAVR. A breakdown analysis of the total cost in the high-risk group showed both pre- and postoperative costs to be significantly higher with SAVR than with TAVR; however, operative costs were higher with TAVR. Up to 3 years, the overall survival in both groups did not significantly differ between TAVR and SAVR. Our findings suggest that from the perspective of total medical costs, TAVR is more suitable than SAVR for high-risk older adults.

Debranching thoracic endovascular aortic repair for distal aortic arch aneurysm in elderly patients aged over 75 years old.

BACKGROUND: We examined the outcome of debranching thoracic endovascular aortic repair (d-TEVAR) without sternotomy for distal aortic arch aneurysm in patients aged ≥75 years. METHODS: Patients who underwent d-TEVAR or TAR for aortic arch aneurysm between 2008 and 2015 at our hospital and aged ≥75 years were included. Age, sex, left ventricular ejection fraction, preoperative creatinine level, diabetes, cerebrovascular disease, and chronic obstructive pulmonary disease were matched using PS. RESULTS: Among 74 patients (d-TEVAR: 51, TAR: 23), 17 patients in each group were matched. No difference in surgical outcome was detected between the d-TEVAR and TAR groups, including 30-day death (0% vs. 0%), hospital death (5.8% vs. 0%: p = 0.31) and incidence of cerebral infarction (5.8% vs. 7.6%: p = 0.27) as well as the long-term outcomes of 5-year survival (92.8% vs. 74.8%: p = 0.30) and 5-year aorta-related event-free rate (88.2% vs. 100%: p = 0.15). Average duration of ICU stay (1.3 ± 1.1 days vs. 5.6 ± 1.3 days: p = 0.025) and hospital stay (16.5 ± 5.2 days vs. 37.7 ± 19.6 days: p = 0.017) were significantly shorter in the d-TEVAR group. CONCLUSION: Our results indicated that d-TEVAR is less invasive without affecting long-term outcome up to 5 years. Although the number of the patients included in the study was small, debranching TEVAR could be one of the treatments of the choice in the elderly, especially with comorbidities.

Successful Surgical Remodeling of a Giant Venous Aneurysm Formed in an Autogenous Arteriovenous Fistula: A Case Report.

One complication of an autogenous arteriovenous fistula (AVF) for hemodialysis is the formation of a venous aneurysm. The treatment of a massive aneurysmal AVF generally involves ligation or resection with the use of prosthetic interposition. We present the case of a 46-year-old man in whom an AVF aneurysm was successfully treated by placating the excess free wall of the aneurysm with sutures. This method is a simple and effective intervention for managing aneurysm-associated complications. In addition, this approach helps to maintain the benefits of autogenous access while conserving future dialysis sites.

Can Tolvaptan Protect Renal Function in the Early Postoperative Period of Cardiac Surgery?　- Results of a Single-Center Randomized Controlled Study.

BACKGROUND: Oral administration of tolvaptan, a vasopressin V2receptor antagonist, significantly reduces deterioration of renal function, which has recently been highlighted as an exacerbating factor for adverse events in patients with acute heart failure. In the present study we tested the hypothesis that concomitant administration of tolvaptan with a conventional diuretic is beneficial for perioperative body fluid management in patients who have undergone cardiac surgery.Methods and Results:In all, 280 patients who underwent cardiac surgery were prospectively randomized to concomitant treatment with tolvaptan and a conventional diuretic (tolvaptan group; 147 patients) or treatment with a conventional diuretic alone (control group; 133 patients). Groups were compared in terms of the time required to restore preoperative body weight and the incidence of worsening renal function (WRF), defined as an increase in the serum creatinine level ≥0.3 mg/dL. The time required to restore preoperative body weight was significantly shorter in the tolvaptan than control group (mean [±SD] 3.97±1.95 vs. 5.02±2.83 days, respectively; P<0.001). The incidence of WRF was significantly lower in the tolvaptan than control group (n=11 [7.5%] vs. n=25 [18.8%], respectively; P=0.011). CONCLUSIONS: Administration of tolvaptan with conventional diuretics in the early postoperative period after cardiac surgery could be beneficial in maintaining urine output without affecting renal function and may thus help avoid WRF.

Novel temporary left ventricular assist system with hydrodynamically levitated bearing pump for bridge to decision: initial preclinical assessment in a goat model.

The management of heart failure patients presenting in a moribund state remains challenging, despite significant advances in the field of ventricular assist systems. Bridge to decision involves using temporary devices to stabilize the hemodynamic state of such patients while further assessment is performed and a decision can be made regarding patient management. We developed a new temporary left ventricular assist system employing a disposable centrifugal pump with a hydrodynamically levitated bearing. We used three adult goats (body weight, 58-68 kg) to investigate the 30-day performance and hemocompatibility of the newly developed left ventricular assist system, which included the pump, inflow and outflow cannulas, the extracorporeal circuit, and connectors. Hemodynamic, hematologic, and blood chemistry measurements were investigated as well as end-organ effect on necropsy. All goats survived for 30 days in good general condition. The blood pump was operated at a rotational speed of 3000-4500 rpm and a mean pump flow of 3.2 ± 0.6 L min. Excess hemolysis, observed in one goat, was due to the inadequate increase in pump rotational speed in response to drainage insufficiency caused by continuous contact of the inflow cannula tip with the left ventricular septal wall in the early days after surgery. At necropsy, no thrombus was noted in the pump, and no damage caused by mechanical contact was found on the bearing. The newly developed temporary left ventricular assist system using a disposable centrifugal pump with hydrodynamic bearing demonstrated consistent and satisfactory hemodynamic performance and hemocompatibility in the goat model.

Smooth muscle cell sheet transplantation preserve cardiac function and minimize cardiac remodeling in a rat myocardial infarction model.

BACKGROUND: We examined whether a vascular smooth muscle cell (SMC) sheet is effective in the treatment of a rat myocardial infarction (MI) model. METHODS: We examined the effect of SMC sheet on the cardiac function and cardiac remodeling in a rat MI model in comparison with their effect of dermal fibroblast (DFB) sheet in vivo. Furthermore, we estimated the apoptosis and secretion of angiogenic factor of SMC under hypoxic condition in comparison with DFB. Seven days after MI, monolayer cell sheets were transplanted on the infarcted area (SMC transplantation group, SMC-Tx; DFB transplantation group, DFB-Tx; no cell sheet transplantation group, Untreated; neither MI nor cell sheet transplantation group, Sham). We evaluated cardiac function by echocardiogram, degree of cardiac remodeling by histological examination, and secretion of angiogenic growth factor by enzyme immunoassay. RESULTS: Twenty-eight days after transplantation, SMC-Tx showed the following characteristics compared with the other groups: 1) significantly greater fractional area shortening (SMC-Tx, 32.3 ± 2.1 %; DFB-Tx, 23.3 ± 2.1 %; untreated, 25.1 ± 2.6 %), 2) suppressed left ventricular dilation, smaller scar expansion, and preserved wall thickness of the area at risk and the posterior wall, 3) decreased fibrosis, preserved myocardium in the scar area, and greater number of arterioles in border-zone, 4) tight attachment of SMC sheets on the scarred myocardium, and less apoptotic cell death. In in vitro experiments, SMCs secreted higher amounts of basic fibroblast growth factor (SMC, 157.7 ± 6.4 pg/ml; DFB, 3.1 ± 1.0 pg/ml), and showed less apoptotic cell death under hypoxia. CONCLUSIONS: Our results illustrate that transplantation of SMC sheets inhibited the progression of cardiac remodeling and improve cardiac function. These beneficial effects may be due to superior SMC survival.

Aortogastric Fistula Caused by a Foreign Body in a Hiatal Hernia.

Foreign body ingestion is more common in children than in adults, and sharp foreign body ingestion is extremely rare. We report a 93-year-old woman who was unaware of foreign body ingestion and who presented with sudden hematemesis and circulatory collapse. Computed tomography showed a hiatus hernia and part of the stomach herniating in the posterior mediastinum. Additionally, a needle-shaped object was seen penetrating the aorta through the herniated gastric wall. Therefore, immediate endovascular repair of the aorta was performed. Subsequent endoscopy identified a bamboo stick. Therefore, emergent laparotomy and gastrotomy were performed to retrieve the stick, followed by repair of the hernia. The postoperative recovery was uneventful. Such cases are associated with high morbidity, mandating long-term follow-up.

Pulsatile support using a rotary left ventricular assist device with an electrocardiography-synchronized rotational speed control mode for tracking heart rate variability.

We previously developed a novel control system for a continuous-flow left ventricular assist device (LVAD), the EVAHEART, and demonstrated that sufficient pulsatility can be created by increasing its rotational speed in the systolic phase (pulsatile mode) in a normal heart animal model. In the present study, we assessed this system in its reliability and ability to follow heart rate variability. We implanted an EVAHEART via left thoracotomy into five goats for the Study for Fixed Heart Rate with ventricular pacing at 80, 100, 120 and 140 beats/min and six goats for the Study for native heart rhythm. We tested three modes: the circuit clamp, the continuous mode and the pulsatile mode. In the pulsatile mode, rotational speed was increased during the initial 35 % of the RR interval by automatic control based on the electrocardiogram. Pulsatility was evaluated by pulse pressure and dP/dt max of aortic pressure. As a result, comparing the pulsatile mode with the continuous mode, the pulse pressure was 28.5 ± 5.7 vs. 20.3 ± 7.9 mmHg, mean dP/dt max was 775.0 ± 230.5 vs 442.4 ± 184.7 mmHg/s at 80 bpm in the study for fixed heart rate, respectively (P < 0.05). The system successfully determined the heart rate to be 94.6 % in native heart rhythm. Furthermore, pulse pressure was 41.5 ± 7.9 vs. 27.8 ± 5.6 mmHg, mean dP/dt max was 716.2 ± 133.9 vs 405.2 ± 86.0 mmHg/s, respectively (P < 0.01). In conclusion, our newly developed the pulsatile mode for continuous-flow LVADs reliably provided physiological pulsatility with following heart rate variability.

In-body tissue-engineered aortic valve (Biovalve type VII) architecture based on 3D printer molding.

In-body tissue architecture--a novel and practical regeneration medicine technology--can be used to prepare a completely autologous heart valve, based on the shape of a mold. In this study, a three-dimensional (3D) printer was used to produce the molds. A 3D printer can easily reproduce the 3D-shape and size of native heart valves within several processing hours. For a tri-leaflet, valved conduit with a sinus of Valsalva (Biovalve type VII), the mold was assembled using two conduit parts and three sinus parts produced by the 3D printer. Biovalves were generated from completely autologous connective tissue, containing collagen and fibroblasts, within 2 months following the subcutaneous embedding of the molds (success rate, 27/30). In vitro evaluation, using a pulsatile circulation circuit, showed excellent valvular function with a durability of at least 10 days. Interposed between two expanded polytetrafluoroethylene grafts, the Biovalves (N = 3) were implanted in goats through an apico-aortic bypass procedure. Postoperative echocardiography showed smooth movement of the leaflets with minimal regurgitation under systemic circulation. After 1 month of implantation, smooth white leaflets were observed with minimal thrombus formation. Functional, autologous, 3D-shaped heart valves with clinical application potential were formed following in-body embedding of specially designed molds that were created within several hours by 3D printer.

Two cases of thoracic aortic aneurysm with right aortic arch: comparison of two operative strategies for hybrid thoracic endovascular repair.

Hybrid TEVAR was performed in 2 patients with right aortic arch accompanied by Kommerell's diverticulum and aortic aneurysm. In patient 1, total debranch + TEVAR was performed with 1-stage median sternotomy. In patient 2, total arch replacement and insertion of a peripheral elephant trunk were performed first, followed by TEVAR. No endoleaks or aortic events were observed in either case during the observation period, and both patients had good postoperative clinical courses. We report our experience with two such cases that were treated with two different methods of hybrid TEVAR, and discuss the merits and demerits of each treatment method.

Novel control system to prevent right ventricular failure induced by rotary blood pump.

Right ventricular (RV) failure is a potentially fatal complication after treatment with a left ventricular assist device (LVAD). Ventricular septal shift caused by such devices is an important factor in the progress of RV dysfunction. We developed a control system for a rotary blood pump that can change rotational speed (RS) in synchrony with the cardiac cycle. We postulated that decreasing systolic RS using this system would alter ventricular septal movement and thus prevent RV failure. We implanted the EVAHEART ventricular assist device into seven adult goats weighing 54.1 ± 2.1 kg and induced acute bi-ventricular dysfunction by coronary embolization. Left and RV pressure was monitored, and ventricular septal movement was echocardiographically determined. We evaluated circuit-clamp mode as the control condition, as well as continuous and counter-pulse modes, both with full bypass. As a result, a leftward ventricular septal shift occurred in continuous and counter-pulse modes. The septal shift was corrected as a result of decreased RS during the systolic phase in counter-pulse mode. RV fractional area change improved in counter-pulse (59.0 ± 4.6%) compared with continuous (44.7 ± 4.0%) mode. In conclusion, decreased RS delivered during the systolic phase using the counter-pulse mode of our new system holds promise for the clinical correction of ventricular septal shift resulting from a LVAD and might confer a benefit upon RV function.

Optimal timing of aortic valve replacement in elderly patients with severe aortic stenosis.

PURPOSE: The elderly population with severe aortic stenosis (AS) requiring aortic valve replacement (AVR) is increasing. The optimal timing of AVR in these patients has been under discussion. METHODS: We retrospectively reviewed the data from severe AS patients (n = 84) who underwent AVR with/without concomitant procedures from 2005 to 2010. The symptom status, preoperative data, operative outcome, late survival and freedom from cardiac events were compared between elderly patients (age ≥80 years [n = 31]) and younger patients (age <80 years [n = 53]). RESULTS: The operative mortality in elderly patients (3.2 %) and younger patients (3.8 %) was comparable. The symptoms in elderly patients were more severe and hospitalized heart failure (HF) was more frequently noted as the primary symptom (p = 0.017). Patients with and without hospitalized HF differed significantly in late survival and freedom from cardiac events (p = 0.001), but advanced age had no significant effect. The results of a Cox proportional hazards analysis revealed that hospitalized HF was a significant predictor for cardiac events after AVR, irrespective of age (hazard ratio 6.93, 95 % confidence interval 1.83-26.26, p < 0.004). CONCLUSIONS: In elderly patients with severe AS, surgery should be recommended even in the presence of minimal symptoms and should be performed before the onset of life-threatening HF.

Missing leaflet: a rare cause of structural deterioration of a bovine pericardial aortic bioprosthesis-report of a case.

We experienced a rare cause of aortic bioprosthesis deterioration in which one of the leaflets disappeared 8.7 years after primary aortic valve replacement (AVR) in a male octogenarian. Successful redo AVR with a 23-mm Magna EASE (Carpentier-Edwards, Irvine, CA) was performed. No embolic complications occurred. We were unable to identify the cause of this devastating complication. When heart failure symptoms develop in patients with bioprostheses, clinicians should therefore consider a diagnosis of acute progression of structural valve deterioration and follow the patient carefully with echocardiography.

Development of a novel drive mode to prevent aortic insufficiency during continuous-flow LVAD support by synchronizing rotational speed with heartbeat.

Aortic insufficiency (AI) is a serious complication for patients on long-term support with left ventricular assist devices (LVAD). Postoperative aortic valve opening is an important predictor of AI. A system is presently available that can promote native aortic flow by reducing rotational speed (RS) for defined intervals. However, this system can cause a reduction in pump flow and lead to insufficient support. We therefore developed a novel "delayed copulse mode" to prevent AI by providing both minimal support for early systole and maximal support shortly after aortic valve opening by changing the RS in synchronization with heartbeat. To evaluate whether our drive mode could open the aortic valve while maintaining a high total flow (sum of pump flow and native aortic flow), we installed a centrifugal LVAD (EVAHEART(®); Sun Medical) in seven goats each with normal hearts and acute LV dysfunction created by micro-embolization of the coronary artery. We intermittently switched the drive mode from continuous (constant RS) with 100 % bypass to delayed copulse mode with 90 % bypass. Total flow did not significantly change between the two modes. The aortic valve opened when the delayed copulse mode was activated. The delayed copulse mode allowed the aortic valve to open while maintaining a high total flow. This novel drive mode may considerably benefit patients with severe heart failure on long-term LVAD support by preventing AI.

Change in myocardial oxygen consumption employing continuous-flow LVAD with cardiac beat synchronizing system, in acute ischemic heart failure models.

Aiming the 'Bridge to Recovery' course, we have developed a novel left ventricular assist device (LVAD) controlling system. It can change the rotational speed of the continuous flow LVAD, EVAHEART, synchronized with the cardiac beat. Employing this system, we have already demonstrated that myocardial oxygen consumption (MVO2), which is considered to be equivalent to native heart load, changes in the hearts of normal goats. Herein, we examined changes in goats with acute ischemic heart failure. We studied 14 goats (56.1 ± 6.9 kg) with acute ischemic heart failure due to coronary microsphere embolization. We installed the EVAHEART and drive in four modes: "circuit-clamp", "continuous support", "counter-pulse", and "co-pulse", with 50 and 100 % bypass. In comparison to the circuit-clamp mode, MVO2 was reduced to 70.4 ± 17.9 % in the counter-pulse mode and increased to 90.3 ± 14.5 % in the co-pulse mode, whereas it was 80.0 ± 14.5 % in the continuous mode, with 100 % bypass (p < 0.05). The same difference was confirmed with 50 % bypass. This means that we may have a chance to change the native heart load by controlling the LVAD rotation in synchrony with the cardiac rhythm, so we named our controller as the Native Heart Load Control System (NHLCS). Employing changeable MVO2 with NHLCS according to the patient's condition may provide more opportunity for native heart recovery with LVAD, especially for patients with ischemic heart diseases.