Association between left ventricular ejection fraction and mortality after Bentall procedure.

Root infection or dissection involving coronary artery frequently necessitates an emergent Bentall procedure, with low left ventricular ejection fraction (LVEF). In contrast, concerning an elective Bentall for aneurysm, surgeons should balance the risk and benefit of surgery, especially in low LVEF cases. We investigated the association between preoperative LVEF and outcomes after Bentall. We analyzed 98 patients undergoing Bentall between April 2000 and March 2020. The patients were stratified into three groups: (a) 65 with LVEF ≥ 60%, (b) 21 with LVEF 45 to < 60%, and (c) 12 with LVEF < 45%. Baseline characteristics, survivals, and major adverse cardiovascular events (MACE) were compared. To assess potential non-linear relationship between LVEF and mortality, cubic spline analysis was conducted. Median age was similar (a vs b vs c, 52 vs 50 vs 44). In all groups, elective root aneurysm was 50-60%, indicating the rest were complicated and sick. Operative mortality was the highest in group c (4.6% vs 9.5% vs 16.7%, p = 0.294). Survival and MACE-free rate were the worst in group c, though their 10-year survival was 40%. LVEF was an independent risk for mortality, and cubic spline analysis showed potential non-linear association between LVEF and mortality. Although LVEF is an independent predictor of mortality after Bentall, long-term survival was occasionally achieved in low LVEF cases. While surgeons should carefully balance the risk of low LVEF and the benefit of surgery in elective cases, we should perform a non-elective procedure as needed, even if LVEF is low.

Prone ex vivo lung perfusion protects human lungs from reperfusion injury.

BACKGROUND: We previously reported beneficial effects of prone positioning during ex vivo lung perfusion (EVLP) using porcine lungs. In this study, we sought to determine if prone positioning during EVLP was beneficial in human donor lungs rejected for clinical use. METHODS: Human double lung blocs were randomized to prone EVLP (n = 5) or supine EVLP (n = 5). Following 16 h of cold storage at 4°C and 2 h of cellular EVLP in either the prone or supine position. Lung function, compliance, and weight were evaluated and transplant suitability determined after 2 h of EVLP. RESULTS: Human lungs treated with prone EVLP had significantly higher partial pressure of oxygen/fraction of inspired oxygen (P/F) ratio [348 (291-402) vs. 199 (191-257) mm Hg, p = 0.022] and significantly lower lung weight [926(864-1078) vs. 1277(1029-1483) g, p = 0.037] after EVLP. 3/5 cases in the prone group were judged suitable for transplant after EVLP, while 0/5 cases in the supine group were suitable. When function of upper vs. lower lobes was evaluated, prone EVLP lungs showed similar P/F ratios and inflammatory cytokine levels in lower vs. upper lobes. In contrast, supine EVLP lungs showed significantly lower P/F ratios [68(59-150) vs. 467(407-515) mm Hg, p = 0.012] and higher tissue tumor necrosis factor alpha levels [100.5 (46.9-108.3) vs. 39.9 (17.0-61.0) ng/ml, p = 0.036] in lower vs. upper lobes. CONCLUSIONS: Prone lung positioning during EVLP may optimize the outcome of EVLP in human donor lungs, possibly by improving lower lobe function.

Significance of Lung Weight in Cellular Ex Vivo Lung Perfusion.

BACKGROUND: Currently, pulmonary edema is evaluated via surgical inspection and palpation in donor lungs, and there is no quantitative standard diagnostic tool for evaluating pulmonary edema in donor procurement and ex vivo lung perfusion (EVLP). The purpose of this study was to investigate the significance of lung weight at the donor hospital and lung weight during EVLP as a complementary parameter of transplant suitability in EVLP. MATERIALS AND METHODS: Twenty-one of rejected human lungs were perfused in cellular EVLP. Transplant suitability was evaluated at 2 h as per standard criteria of Lund-protocol EVLP. RESULTS: Lung weight at donor hospital was significantly correlated with PaO2/FiO2 (P/F) ratio in EVLP (r = -0.44). There was a significant difference in lung weight at donor hospital between suitable cases (n = 13) and nonsuitable cases (n = 8). Light lung group (lung weight at donor hospital < 1280 g; n = 17) was suitable for transplant in 76%, whereas none of heavy lung group (lung weight at donor hospital ≥ 1280 g; n = 4) was suitable (P < 0.05). Lung weight at 2 h and lung weight change during EVLP were significantly associated with P/F ratio at 2 h and transplant suitability (P < 0.05, each). CONCLUSIONS: Our findings demonstrate that lung weight at donor hospital, lung weight change, and lung weight at 2 h of EVLP might be a predictor of P/F ratio and transplant suitability in cellular EVLP.

Hyperinflation With Pulmonary Dysfunction in Donor Lungs With Smoking History During Lung Perfusion.

BACKGROUND: Donor lungs with smoking history are perfused in ex vivo lung perfusion (EVLP) to expand donor lung pool. However, the impact of hyperinflation of perfused lungs in EVLP remains unknown. The aim of this study was to investigate the significance of hyperinflation, using an ex vivo measurement delta VT, during EVLP in smoker's lungs. MATERIALS AND METHODS: Seventeen rejected donor lungs with smoking history of median 10 pack-years were perfused for 2 h in cellular EVLP. Hyperinflation was evaluated by measuring delta VT = inspiratory - expiratory tidal volume (VT) difference at 1 h. All lungs were divided into two groups; negative delta VT (n = 11, no air-trapping pattern) and positive delta VT (n = 6, air-trapping pattern). Transplant suitability was judged at 2 h. By using lung tissue, linear intercept analysis was performed to evaluate the degree of hyperinflation. RESULTS: The positive delta VT group had significantly lower transplant suitability than the negative delta VT group (16 versus 81%, P = 0.035). The positive delta VT group was significantly associated with lower partial pressure of oxygen/fraction of inspired oxygen ratio ratio (278 versus 356 mm Hg, P = 0.049), higher static compliance (119 versus 98 mL/cm H2O, P = 0.050), higher lung weight ratio (1.10 versus 0.96, P = 0.014), and higher linear intercept ratio (1.52 versus 0.93, P = 0.005) than the negative delta VT group. CONCLUSIONS: Positive delta VT appears as an ex vivo marker of ventilator-associated lung hyperinflation of smoker's lungs during EVLP.

Cellular Ex Vivo Lung Perfusion Beyond 1 Hour May Improve Marginal Donor Lung Assessment.

BACKGROUND: Ex vivo lung perfusion (EVLP) permits extended evaluation of donor lungs for transplant. However, the optimal EVLP duration of Lund protocol is unclear. Using human lungs rejected for clinical transplant, we sought to compare the results of 1 versus 2 h of EVLP using the Lund protocol. METHODS: Twenty-five pairs of human lungs rejected for clinical transplant were perfused with the Lund EVLP protocol. Blood gas analysis, lung compliance, bronchoscopy assessment, and perfusate cytokine analysis were performed at both 1 and 2 h. Recruitment was performed at both time points. Donor lung transplant suitability was determined at both time points. RESULTS: All cases were divided into four groups based on transplant suitability assessment at 1 h and 2 h of EVLP. In group A (n = 10), lungs were judged suitable for transplant at both 1 and 2 h of EVLP. In group B (n = 6), lungs were suitable at 1 h but nonsuitable at 2 h. In group C (n = 2), lungs were nonsuitable at 1 h but suitable at 2 h. Finally, in group D (n = 7), lungs were nonsuitable for transplant at both time points. In both groups B and C (n = 8), the transplant suitability assessment changed between 1 and 2 h of EVLP. CONCLUSIONS: In human lungs rejected for transplant, transplant suitability differed at 1 versus 2 h of EVLP in 32% of lungs studied. Evaluation of lungs with Lund protocol EVLP beyond 1 h may improve donor organ assessment.

A novel concept for evaluation of pulmonary function utilizing PaO2/FiO2 difference at the distinctive FiO2 in cellular ex vivo lung perfusion-an experimental study.

For more accurate lung evaluation in ex vivo lung perfusion (EVLP), we have devised a new parameter, PaO2 /FiO2 ratio difference (PFD); PFD1-0.4  = P/F ratio at FiO2 1.0 - P/F ratio at FiO2 0.4. The aim of this study is to compare PFD and transplant suitability, and physiological parameters utilized in cellular EVLP. Thirty-nine human donor lungs were perfused. At 2 h of EVLP, PFD1-0.4 was compared with transplant suitability and physiological parameters. In a second study, 10 pig lungs were perfused in same fashion. PFD1-0.4 was calculated by blood from upper and lower lobe pulmonary veins and compared with lobe wet/dry ratio and pathological findings. In human model, receiver operating characteristic curve analysis showed PFD1-0.4 had the highest area under curve, 0.90, sensitivity, 0.96, to detect nonsuitable lungs, and significant negative correlation with lung weight ratio (R2  = 0.26, P < 0.001). In pig model, PFD1-0.4 on lower and upper lobe pulmonary veins were significantly associated with corresponding lobe wet/dry ratios (R2  = 0.51, P = 0.019; R2  = 0.37, P = 0.060), respectively. PFD1-0.4 in EVLP demonstrated a significant correlation with lung weight ratio and allowed more precise assessment of individual lobes in detecting lung edema. Moreover, it might support decision-making in evaluation with current EVLP criteria.

Single-center experience of the bridge-to-bridge strategy using the Nipro paracorporeal ventricular assist device.

Currently, we use the Nipro paracorporeal VAD (p-VAD) for initial short-term ventricular support, as a bridge to decision (BTD) or a bridge to candidacy (BTC) treatment, in Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) levels 1 and 2 patients. However, it is possible that compared to patients with primary implantable-VADs (P-iVAD), the bridge-to-bridge (BTB) patients are more likely to develop complications. This retrospective study used data from 24 consecutive BTB patients who were initially implanted with Nipro p-VAD as BTD or BTC treatments between April 2011 and March 2016, and subsequently underwent conversion to an i-VAD. The data from 72 patients who underwent a primary i-VAD (P-iVAD) procedure were used for comparison. Between the two groups, there was no significant difference in the incidence of infectious events (p = 0.72) or stroke (p = 0.44). Orthotropic heart transplantation was performed in 6 of the 24 patients in the BTB group and in 21 of the 72 patients in the P-iVAD group. The 1- and 2-year survival rates were 95.8% and 95.8% in the BTB group and 91% and 85.8% in the P-iVAD group; these values were not significantly different between groups (p = 0.91). Based on these results we conclude that BTB using Nipro p-VAD is a reasonable strategy for treating patients with severe decompensated end-stage heart failure.

Central aortic valve closure successfully treated aortic insufficiency of the patient with Jarvik 2000 continuous flow left ventricular assist device: a case report.

Aortic insufficiency (AI) is a significant complication of long-term support of continuous flow left ventricular assist device (CF-LVAD) for patients with end-stage heart failure. A 26-year-old female with osteogenesis imperfecta (OI) was diagnosed with dilated phase hypertrophic cardiomyopathy (d-HCM)) and was implanted with Jarvik 2000, for bridge to transplantation. AI gradually developed and surgical intervention was indicated. We performed central aortic valve closure (CAVC) instead of valve replacement 20 months after CF-LVAD implantation. Patient's symptoms dramatically improved postoperatively. This is the first report of CAVC for a patient supported with Jarvik 2000.

A delayed splenic rupture after transcatheter arterial embolization required total splenectomy in a patient with an implantable left ventricular assist device.

We successfully managed a splenic injury and delayed splenic rupture in a patient with an implantable left ventricular assist device (iLVAD). A 42-year-old man with an iLVAD for idiopathic dilated cardiomyopathy was admitted to our department complaining of dizziness. Laboratory data showed severe anemia, and computed tomography demonstrated a traumatic splenic injury. Following conservative treatment, partial splenic embolization was performed. Fifteen days after the intervention, the patient went into hemorrhagic shock due to delayed splenic rupture. Emergency total splenic embolization was performed, and total splenectomy was conducted later to prevent re-bleeding or abscess formation. His postoperative course was uneventful, and he was discharged on postoperative day 22. Finally, he underwent orthotropic heart transplantation without post-splenectomy sepsis or thrombotic complications 472 days after splenectomy. Splenic injury should be considered as a possible complication of iLVAD. In addition, careful follow-up after transcatheter arterial embolization for splenic injury is essential for managing delayed splenic rupture.

A successful management of infection of the left ventricular assist device by pump exchange: conversion from DuraHeart to Jarvik 2000.

We successfully controlled infection of a left ventricular assist device by performing pump exchange. A 53-year-old man was implanted with DuraHeart for ischemic cardiomyopathy as a bridge to transplantation. Two years later, he was hospitalized with the diagnosis of driveline infection. The blood cultures detected Pseudomonas aeruginosa. During the admission, he developed brain hemorrhage perhaps due to septic emboli. The chest computed tomography scan revealed a small defect inside the outflow graft of the DuraHeart, which was highly suspected of vegetation. He underwent pump exchange, from DuraHeart to Jarvik 2000 with concomitant omentopexy. His postoperative course was uneventful, and he was discharged with no sequela of the brain hemorrhage. Four months after the pump exchange, he successfully underwent heart transplantation. No infectious tissue was observed in the pericardial space at the time of heart transplantation. Pump exchange is an effective way to manage refractory left ventricular assist device infection, and the timing of surgical intervention is of great importance.

Successful management of apical abscess after Nipro left ventricular assisted device explantation by removal of apical cuff and omentopexy.

Nipro-Toyobo-paracorporeal pulsatile flow VAD (Nipro VAD; Nipro, Osaka, Japan) has been used most commonly as a paracorporeal VAD (p-VAD) in Japan. There are few reports describing clinical course of post LVAD explantation and its complication. We herein present two cases of apical abscess after the explantation of the device. SSI is a main risk factor of formation of the apical abscess at the time of LVAD explantation. It is mandatory to perform sufficient debridement and closure of the layers including abdominal muscle and anterior abdominal fascia at exit sites in the explantation surgery. Omentopexy is also helpful for prevention from infection. Routine removal of apical cuff and outflow graft could be considered as one of the options when LVAD is explanted as bridge to recovery.

A New Suturing Device for Small Arteries.

Endoscope-assisted surgery and robot-assisted surgery are not common in cardiac surgery, particularly coronary artery bypass grafting, because of the complex nature of the procedures. We developed a new suturing device that allows for easy performance of such cardiac surgeries in comparison with conventional suturing methods. A total of 63 rabbits were used in this study. The right carotid artery was bypassed using the same side of the jugular vein under endoscopic guidance. Of these, 48 rabbits were operated on using the new devices and 15 rabbits were operated on using conventional polypropylene sutures. The proximal suturing time was 16.6 ± 5.3 minutes in the group that underwent surgery using the new device (group D) and 22.8 ± 7.6 minutes in the control group (group C; P < 0.05). The distal suture time was 16.3 ± 4.2 minutes in group D and 22.8 ± 6.0 minutes in group C (P < 0.05). The operation time was 113.0 ± 15.8 minutes in group D and 136.7 ± 20.6 minutes in group C (P < 0.05). Graft flow was 19.9 ± 12.8 mL/minute in group D and 12.1 ± 11.3 mL/minute in group C (P < 0.05). Thus, the operation time and the suture time differed significantly between the groups. This device provides advantages in endoscopic surgery compared to the conventional suture method.

[Temporary use of centrifugal pump for pump thrombosis in patients with paracorporeal ventricular assist device].

Nipro paracorporeal ventricular assist device( VAD) is often associated with pump thrombosis which causes severe complications such as brain infarction, often requiring pump change. However, Nipro VAD pump is an expensive device and it is difficult to change pumps frequently at a short interval. We have temporarily used Rotaflow centrifugal pump for recurrent pump thrombosis in patients with Nipro VADs. From January 2012 through December 2013, 19 patients underwent Nipro VADs implantation at our institution, and 9 of them underwent pump change from Nipro pumps to Rotaflow centrifugal pumps. A total of 25 Rotaflow centrifugal pumps were used in these 9 patients, with the total circulatory support duration of 526 days. The median support period was 15 days (range;2-128 days). There were 2 cerebrovascular accidents and 1 Rotaflow pump circuit thrombosis during this period. Change from Rotaflow to Nipro VAD pump resulted in decrease in hematocrit by about 3 point. There was no difference in liver or renal function between before and after the pump change. Our results suggest that temporary use of Rotaflow centrifugal pump for recurrent pump thrombosis in patients with Nipro VADs may be a promising alternative.

Development of a suturing device for anastomosis for small caliber arteries.

The use of minimally invasive and robotic operations has been increasing for coronary artery bypass surgery; however, no suturing devices have been universally adopted for use in these procedures. We developed a new suturing device that enables omission of manual ligation after a running suture. Twenty-two rabbits were used in this study. In 22 rabbits, the right carotid artery was bypassed using an autologous jugular vein graft. Half of the animals were operated on using the new device and the other half using conventional suturing methods. Postoperative evaluations were performed at 1, 3, and 6 months. Suturing time was 15.6 ± 2.4 min in the device group and 16.6 ± 4.4 min in the control group (p = 0.34). Graft patency and blood flow measurements were not significantly different between the two groups. Histopathological examination of the anastomotic site showed common inflammatory responses in both groups. No particular histopathological change was seen related to the device. In conclusion, the safety of the new suturing device was confirmed, and its efficacy was equal to that of the conventional suturing technique.

Lower extremity artery thromboembolism during removal of Impella after repair for ventricular septal rupture: A case report.

Although the anticoagulant complications of Impella are well known, the timing of heparin administration when using Impella immediately after open heart surgery has not been established. We report a case of a 59-year-old man with Impella-assisted repair of a ventricular septal perforation after acute myocardial infarction who developed thromboembolism of the lower extremity arteries after removal of Impella.

Outcomes of isolated CABG from "OPCAB favor institution" for patients with left ventricular dysfunction.

OBJECTIVES: Although off-pump coronary artery bypass (OPCAB) has been reported to have better short-term results than on-pump coronary artery bypass (ONCAB) in terms of bleeding and stroke even in patients with cardiac dysfunction, details are unknown. The purpose of this study was to evaluate the outcomes of CABG (coronary artery bypass graft) in patients with low cardiac function based on our treatment policy. METHODS: Retrospectively, we reviewed patients with low ejection fraction (< 35%), who underwent isolated OPCAB or ONCAB between 2013 and 2020 in our institute. RESULTS: Isolated CABG was performed for 67 patients: 54 OPCABs and 13 ONCABs. In the ONCAB group, six were converted from OPCAB. Patients with AMI, heart failure, liver dysfunction, cardiogenic shock, and ventricular arrhythmia were more common in the ONCAB group. More patients required postoperative mechanical circulatory support in the ONCAB group. Intra-operative blood transfusion, ICU stay, intubation time, and hospital stay were significantly worse in the ONCAB group. Postoperative graft patency was 91.5%. Hospital mortality was 7.5%. Mid-term survival at 30-day, 1-year, and 5-year were 98.5%, 84.6%, and 75.8%, respectively. CONCLUSION: In our institute, ONCAB was selected for the patients who could not complete treatment with OPCAB due to poor preoperative circulatory status. Our treatment policy for the patients with impaired cardiac function was acceptable.

Aortic valve replacement of a quadricuspid aortic valve with right coronary artery ostium adjacent to one of the commissures.

BACKGROUND: Quadricuspid aortic valve is a rare congenital heart disease that may be associated with a different anatomical relationship between the coronary artery ostium and the commissure. CASE PRESENTATION: Herein, we report a case of a 59-year-old woman who underwent aortic valve replacement for a quadricuspid aortic valve with severe aortic regurgitation. Intraoperatively, the aortic valve had four cusps of almost equal size and the right coronary artery arose adjacent to the commissure between the right coronary cusp and one of the two non-coronary cusps. The annular stitches were placed in a non-everting mattress fashion with pledgets on the ventricular side, and stitches near the right coronary ostium were transitioned to the subannular ventricular myocardium to maintain the distance from the ostium. A one-step smaller-sized prosthesis was selected to avoid an oversized prosthetic valve potentially compressing the right coronary ostium. CONCLUSIONS: When performing aortic valve replacement for a quadricuspid aortic valve, careful observation of the coronary location and means to avoid coronary ostium obstruction are essential.

Delayed diagnosis of severe traumatic tricuspid regurgitation after traffic injury.

Traumatic accidents sometimes cause primary traumatic tricuspid regurgitation (TR), and the diagnosis is occasionally delayed due to the load adaptability of the right ventricle, which may lead to fatal outcomes. Here, we report a case of a 28-year-old man with traumatic TR, which presented with late-onset exertional dyspnea 5 years after a blunt chest injury from a bicycle accident. The chordae tendineae of anterior tricuspid leaflet was ruptured with right heart dilatation, and he underwent surgical tricuspid valvuloplasty. For the patients having a chest traumatic accident, echocardiographic screening is recommended considering TR occurrence. .

Safety of retrograde cerebral perfusion under moderate hypothermia for hemiarch replacement.

OBJECTIVES: Aortic surgeries performed under moderate hypothermia require antegrade cerebral perfusion. The influence of retrograde cerebral perfusion under moderate hypothermic circulatory arrest remains unknown. To clarify this effect, this study aimed to compare the early outcomes of retrograde versus antegrade cerebral perfusion under moderate hypothermia for hemiarch replacement. METHODS: Between March 2009 and April 2020, 391 hemiarch replacements under moderate hypothermic circulatory arrest via median sternotomy were performed at our institution. Of these, 70 involved retrograde perfusion and 162 involved antegrade perfusion. Propensity score matching was used to compare 61 pairs of retrograde and antegrade cases. RESULTS: Retrograde and antegrade strategy under moderate hypothermia resulted in comparable operative mortality (3.3% vs. 1.6%, P > 0.99), permanent neurological deficits (8.5% vs. 6.6%, P > 0.99), and temporary neurological deficits (24.6% vs. 39.3%, P = 0.33). Retrograde surgery was associated with shorter circulatory arrest times (31.4 ± 8.2 min vs. 37.4 ± 12.2 min, P = 0.005) and fewer red blood cell transfusions (4.6 ± 3.9 units vs. 8.2 ± 5.1 units, P < 0.001) than those with antegrade surgery. CONCLUSIONS: Retrograde cerebral perfusion under moderate hypothermia for hemiarch replacement yields excellent operative outcomes, equivalent to those achieved using an antegrade strategy.

Ventricular assist device bridging with gender-mismatch increases rejection and decreases survival following a heart transplant.

OBJECTIVES: Survival is poor following an orthotopic heart transplant with gender-mismatched donors and recipients. Patients bridged to an orthotopic heart transplant with a ventricular assist device (VAD) frequently become sensitized. We hypothesized that the combination of VAD bridging and gender-mismatch may result in greater rejection and poorer survival. METHODS: Data were obtained from the United Network of Organ Sharing database. Patients were divided into 4 groups: (i) VAD recipients who received a heart from a gender-matched donor (VAD-M); (ii) VAD recipients who received a heart from a gender-mismatched donor (VAD-MM); (iii) noVAD recipients who received a heart from a gender-matched donor (noVAD-M); and (iv) noVAD recipients who received a heart from a gender-mismatched donor (noVAD-MM). Rejection episodes within 1-year post-transplant and transplant survival were compared in VAD-M versus VAD-MM and noVAD-M versus noVAD-MM groups, respectively. RESULTS: Between January 2000 and June 2017, of 33 401 adult patients who underwent heart transplants, 8648, 2441, 12 761 and 4992 patients were identified as VAD-M, VAD-MM, noVAD-M and noVAD-MM, respectively. Rejection within 1-year post-transplant occurred in 23.3% and 27.3% of the VAD-M and VAD-MM groups, respectively (P < 0.01) and in 21.8% and 23.6% of the noVAD-M and noVAD-MM groups (P = 0.02), respectively. In an adjusted survival analysis, the VAD-MM group showed significantly worse survival than the VAD-M group (P < 0.01), whereas there was no significant difference between the noVAD-M and noVAD-MM groups (P = 0.21). CONCLUSIONS: Our results indicated that the combination of VAD bridging and gender-mismatch caused greater rejection and worse survival following a transplant. Further study is necessary to prove comparable post-transplant survival of gender-matched or -mismatched recipients without VAD bridging.