Clinical and Sociodemographic Factors Associated With Health-Related Quality of Life in Patients With Adult Congenital Heart Disease　- A Nationwide Cross-Sectional Multicenter Study.

BACKGROUND: Little is known about clinical or sociodemographic factors that influence health-related quality of life (HRQoL) in patients with adult congenital heart disease (ACHD).Methods and Results: We conducted a nationwide prospective cross-sectional multicenter study at 4 large ACHD centers in Japan. From November 2016 to June 2018, we enrolled 1,223 ACHD patients; 1,025 patients had an HRQoL score. Patients completed a questionnaire survey, including sociodemographic characteristics, and the 36-Item Short-Form Health Survey (SF-36). To determine factors associated with HRQoL, correlations between 2 SF-36 summary scores (i.e., physical component score [PCS] and mental component score [MCS]) and other clinical or sociodemographic variables were examined using linear regression analysis. In multivariable analysis, poorer PCS was significantly associated with 11 variables, including older age, higher New York Heart Association class, previous cerebral infarction, being unemployed, and limited participation in physical education classes and sports clubs. Poorer MCS was associated with congenital heart disease of great complexity, being part of a non-sports club, current smoking, and social drinking. Student status and a higher number of family members were positively correlated with MCS. CONCLUSIONS: This study demonstrates that HRQoL in ACHD patients is associated with various clinical and sociodemographic factors. Further studies are needed to clarify whether some of these factors could be targets for future intervention programs to improve HRQoL outcomes.

Changes in the Quality of Life of Patients with Left Ventricular Assist Device and their Caregivers in Japan: Retrospective Observational Study.

Left ventricular assist devices (LVAD) improve quality of life (QOL) in many patients with end-stage severe heart failure, but not in some patients. In addition, the burden on caregivers is expected to increase after LVAD patients are discharged. Our study aimed to investigate the impact of LVAD on the QOL of patients and caregivers. Thirty-two LVAD patients were assessed for changes in QOL, mental status, and activity level using the Euro QOL (EQ-5D-5L), Short Form 12 (SF-12), Minnesota Living with Heart Failure Questionnaire, Hospital Anxiety and Depression Scale (HADS), and Frenchay Activities Index. Twenty-four caregivers were assessed for changes in QOL, mental status, and burden of care using the EQ-5D-5L, SF-12, HADS, and Burden Index of Caregiver (BIC-11). The LVAD patients and caregivers responded contemporaneously regarding two points: pre-and post-LVAD. Patients' physical and mental QOL was significantly improved, but not social QOL and activity level. Caregivers' QOL and burden of care did not change, and anxiety was reduced (p = 0.028). The patients were divided into two groups based on whether EQ-5D-5L was improved: twelve patients in the unimproved group (UG) and twenty patients in the improved group (IG). In the UG, 50% had LVAD-related strokes (p = 0.001, IG: 0%), and their social QOL decreased (p = 0.023). The activity levels improved in the IG. Multi-dimensional analyses on the QOL in LVAD patients yielded mixed results. Anticipated benefits derived from LVAD therapy may be limited by LVAD-related complications such as stroke that negatively impacts on the QOL.

Malignant solitary fibrous tumors of the left atrial endocardium.

Solitary fibrous tumors are typically benign and usually develop in the pleura. We herein report the first case of a solitary fibrous tumor that was pathologically malignant and developed in the left atrial endocardium. A 24-year-old woman underwent resection of a malignant solitary fibrous tumor in her right forearm at another hospital. Computed tomography demonstrated a mass in her right pleura 2 months after the surgery. She was referred to our hospital, and a tumor in her left atrium was subsequently found. She underwent resection of these tumors, and pathological examination showed that they were both malignant solitary fibrous tumors.

Histopathology of anastomotic stenosis after total anomalous pulmonary vein connection.

We report a case of a 10-month-old girl who was diagnosed with pulmonary vein stenosis after total anomalous pulmonary vein connection repair and underwent release of an anastomotic stenosis. Histopathological examinations of the resected anastomotic tissue revealed intimal hyperplasia at the anastomotic site. Predominant lesion cells were identified as myofibroblasts and had the characteristics of fibroblasts and synthetic smooth muscle cells. These cells could be a useful target for preventing anastomotic stenosis after total anomalous pulmonary vein connection repair.

[Effects of Olmesartan Medoxomil on Patients with Thoracic and Thoracoabdominal Aortic Aneurysm;Evaluation of Anti-hypertensive Effect and Possible Suppression of Aneurysmal Dilation( OLM 40 Study)].

We evaluated the blood pressure( BP) lowering effect and possible suppression of aortic enlargement by olmesartan (OLM) in patients with thoracic and thoracoabdominal aortic aneurysm. In this single center prospective, forced titration study, 50 patients were registered between 2008 and 2011. After all patients received any of OLM 10, 20, and 40 mg/day as an initial dose, the dosage of OLM was titrated up to 40 mg as needed during follow-up period. Home BP (HBPs), aortic aneurysm size assessed by computed tomography (CT) scan, indices of renal function were recorded at 3- and 6-months follow-up. Depending on whether 40 mg/day of prescription was continued for more than 4 months or not, the patients were divided into 2 groups:less than 40 mg (<40 mg) and 40 mg groups. Morning HBPs tended to decrease in both groups, and the percent changes in BPs were essentially the same regardless of dosage. The absolute value of aortic diameter tended to slightly enlarge only in <40 mg group. Also in the <40 mg group, the absolute differences in aortic diameter between those at the time of study registration and each follow-up were 0.5±1.8 mm at 3-month and 1.2±2.3 mm at 6-month (p=0.047),whereas the percent changes were 0.9±3.3% and 2.2±4.5% at 3 and 6 months, respectively( p=0.058). As for 40 mg group, the absolute differences and percent changes did not reach statistically significant increase during the follow-up period. No severe renal dysfunction related to OLM 40 mg prescription was observed. Our results imply that OLM 40 mg may suppress aortic aneurysmal dilation independently of blood pressure lowering effect. Further study with larger number of sample size is warranted to assure this observation.

Native Valve Endocarditis due to Staphylococcus warneri Developing in a Patient with Type 1 Diabetes.

A 59-year-old man with type 1 diabetes presented with heart failure. Echocardiography showed large vegetations on the mitral and aortic valves. Blood bacterial culture was positive for Staphylococcus warneri, a coagulase-negative staphylococcus (CoNS) family member. He was diagnosed with native valve endocarditis (NVE) induced by the resident bacteria and ultimately underwent double valve replacement. Retrospectively, slight laboratory data abnormalities and weight loss beginning four months before may have been signs of NVE. He had no history of immunosuppressive therapies or medical device implantation. Thus, CoNS can cause NVE after a long asymptomatic course in patients with poorly controlled diabetes.

Progression of vascular remodeling in pulmonary vein obstruction.

OBJECTIVES: Pulmonary vein obstruction (PVO) frequently occurs after repair of total anomalous pulmonary vein connection with progression of intimal hyperplasia from the anastomotic site toward upstream pulmonary veins (PVs). However, the understanding of mechanism in PVO progression is constrained by lack of data derived from a physiological model of the disease, and no prophylaxis has been established. We developed a new PVO animal model, investigated the mechanisms of PVO progression, and examined a new prophylactic strategy. METHODS: We developed a chronic PVO model using infant domestic pigs by cutting and resuturing the left lower PV followed by weekly hemodynamic parameter measurement and angiographic assessment of the anastomosed PV. Subsequently, we tested a novel therapeutic strategy with external application of rapamycin-eluting film to the anastomotic site. RESULTS: We found the pig PVO model mimicked human PVO hemodynamically and histopathologically. This model exhibited increased expression levels of Ki-67 and phospho-mammalian target of rapamycin in smooth muscle-like cells at the anastomotic neointima. In addition, contractile to synthetic phenotypic transition; that is, dedifferentiation of smooth muscle cells and mammalian target of rapamycin pathway activation in the neointima of upstream PVs were observed. Rapamycin-eluting films externally applied around the anastomotic site inhibited the activation of mammalian target of rapamycin in the smooth muscle-like cells of neointima, and delayed PV anastomotic stenosis. CONCLUSIONS: We demonstrate the evidence on dedifferentiation of smooth muscle-like cells and mammalian target of rapamycin pathway activation in the pathogenesis of PVO progression. Delivery of rapamycin to the anastomotic site from the external side delayed PV anastomotic stenosis, implicating a new therapeutic strategy to prevent PVO progression.

Intraoperative identification of major blood supply to Adamkiewicz artery after multistep surgeries in thoraco-abdominal aortic aneurysm repair.

Herein, we report a case of thoraco-abdominal aortic repair in a 55-year-old man with a multiple treatment history for aortic aneurysm and aortic dissection. A computed tomography scan revealed that the Adamkiewicz artery was connected to an occluded intercostal artery, suggesting that the left inferior epigastric artery was the key artery supplying the Adamkiewicz artery; the key artery was identified through direct monitoring of cerebrospinal fluid temperature and selective hypothermic perfusion. No spinal cord injury was detected during the postoperative period.

Nanobubble technology to treat spinal cord ischemic injury.

Background: Spinal cord ischemic injury is a severe complication of aortic surgery. We hypothesized that cerebrospinal fluid (CSF) oxygenation with nanobubbles after reperfusion could ameliorate spinal cord ischemic injury. Methods: Twenty white Japanese rabbits were categorized into 4 groups of 5 rabbits each: sham group, with balloon catheter insertion into the aorta; ischemia group, with spinal cord ischemic injury by abdominal aortic occlusion; nonoxygenated group, with nonoxygenated artificial CSF irrigation after spinal cord ischemic injury; and oxygenated group, with oxygenated artificial CSF irrigation after spinal cord ischemic injury. At 48 hours after spinal cord ischemic injury, the modified Tarlov score to reflect hind limb movement was evaluated. The spinal cord was histopathologically examined by counting anterior horn cells, and microarray and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analyses were performed. Results: The oxygenated group showed improved neurologic function compared with the ischemia and nonoxygenated groups (P < .01 and P = .019, respectively). Anterior horn neuron prevention in the sham, nonoxygenated, and oxygenated groups was confirmed (mean modified Tarlov score: sham, 9.2 ± 1.9; nonoxygenated, 10.2 ± 2.2; oxygenated, 10.4 ± 2.2; ischemia, 2.7 ± 2.7). Microarray analysis identified 644 genes with twofold or greater increased signals between the ischemia and sham groups. Thirty-three genes related to inflammatory response were enriched among genes differentially expressed between the oxygenated and ischemia groups. Interleukin (IL)-6 and tumor necrosis factor (TNF) expression levels were significantly lower in the oxygenated group compared with the ischemia group, while qRT-PCR showed lower IL-6 and TNF expression levels in the oxygenated group compared with the ischemia group (P < .05). Conclusions: CSF oxygenation with nanobubbles after reperfusion can ameliorate spinal cord ischemic injury and suppress inflammatory responses in the spinal cord.

Maximization of the sealing effect of fibrin glue in aortic surgery.

OBJECTIVES: Fibrin glue is used to reinforce anastomosis in aortic surgery. There has not yet been a consensus on how it should be applied optimally. This study aimed to define the optimal condition of applying fibrin glue. METHODS: In experiment 1, we determined the optimal condition for spraying fibrin glue using an expanded polytetrafluoroethylene graft within a needle hole. The length and area of the fibrin cap within the hole were measured. In experiment 2, methods for applying fibrinogen were assessed by comparing brushing and spraying. In experiment 3, swine aorta segments sutured with a Dacron graft were divided into the following three groups: nothing was applied; fibrinogen was sprayed and rubbed using brush. The aorta was clamped and blood was infused from an occlusion catheter inserted into the graft. The pressure at the first appearance of blood leak was recorded. RESULTS: In experiment 1, among the four groups divided by the pressure and distance of spraying, the fibrin cap area in the group with 0.075 MPa and 2-cm spray distance was significantly larger than that in the group with 0.15 MPa and 2 cm (P < 0.01). In experiment 2, the fibrin cap area in the brushing group was significantly larger than that in the spraying group (P < 0.05). In experiment 3, the capacity to resist endoluminal pressure was higher in the brushing and combined spraying group compared with that in the sequential combined spraying group (P < 0.01). CONCLUSIONS: The brush and spray methods showed excellent hemostatic outcomes.

Temporary ventricular assist device implantation by sternotomy-avoiding technique for bridge-to-decision therapy: a comparison with conventional implantation.

OBJECTIVE: Temporary ventricular assist device (VAD) is a commonly used therapeutic option for cardiogenic shock. Patients requiring this treatment are often critical, and clinical outcomes remain unsatisfactory. This study evaluated the feasibility and efficacy of a sternotomy-avoiding technique for temporary VAD implantation to improve patient outcomes. METHODS: Between December 2012 and November 2018, seven patients underwent temporary VAD implantation by sternotomy-avoiding technique (SA group) and eight by median sternotomy technique (MS group). Pre- and intraoperative characteristics, postoperative 7-day hemodynamic parameters, 30-day mortality, and adverse events were compared between the groups. RESULTS: More than 50% of the patients were mechanically supported before temporary VAD implantation. Cardiopulmonary bypass time was significantly shorter in the SA than in the MS group (84 min vs 215 min; p = 0.011); surgical time tended to be shorter in the SA group (385 min vs 461 min; p = 0.064). Pump index, cardiac index, mixed venous oxygen saturation, and central venous pressure did not differ significantly during the first seven days of support. The 30-day incidence of any adverse event was not significantly different between the groups. No patients in the SA group needed re-exploration for surgical bleeding. Thirty-day all-cause mortality rates were 29% in the SA group and 0% in the MS group (p = 0.11). CONCLUSIONS: The sternotomy-avoiding and conventional techniques resulted in comparable short-term hemodynamic support. The sternotomy-avoiding technique was associated with a potential reduction in risk of re-exploration for bleeding. These results support the usefulness of the sternotomy-avoiding procedure for selected patients.

The incidence, risk factors, and outcomes of gastrointestinal bleeding in patients with a left ventricular assist device: a Japanese single-center cohort study.

Continuous flow-left ventricular assist devices (CF-LVADs) have become a therapeutic option in the management of advanced heart failure. Several studies show that patients with CF-LVAD are at an increased risk of gastrointestinal bleeding (GIB). However, few reports have presented the characteristics of GIB in Japanese populations. We investigated the incidence, etiology, and outcome of GIB in patients with CF-LVAD. Records of adult patients who received CF-LVADs between October 2008 and January 2017 were reviewed. GIB was defined as detection of bleeding sites by any type of diagnostic imaging. 54 patients received CF-LVAD, of which eight (14%) presented with overt GIB (12 events). GIB patients are significantly older (p = 0.04) and their pre-operative inferior vena cava diameter was larger (p = 0.02). Multivariate analysis revealed that the use of Jarvik 2000 (p = 0.003) was a risk factor for GIB. In total, 85.8% of patients were free from GIB at 1 year. The most common site was the small intestine (67%). The most common cause was angiodysplasia (50%). Six patients required blood transfusion (nine events) and four underwent endoscopic clippings (five events); however, no patients needed surgeries. The incidence of GIB in our cohort was similar to the global registry data. Double balloon endoscopy is useful for diagnosis and treatment of small intestinal lesions. Future efforts to further understand the incidence of GIB in Japanese populations by multicenter data are needed.

Prognostic value of the model for end-stage liver disease excluding INR score (MELD-XI) in patients with adult congenital heart disease.

Patients with adult congenital heart disease (ACHD) are at increased risk of developing late cardiovascular complication. However, little is known about the predictive factors for long-term outcome. The Model for End-Stage Liver Disease eXcluding INR (MELD-XI) score was originally developed to assess cirrhotic patients and has the prognostic value for heart failure (HF) patients. In the present study, we examined whether the score also has the prognostic value in this population. We retrospectively examined 637 ACHD patients (mean age 31.0 years) who visited our Tohoku University hospital from 1995 to 2015. MELD-XI score was calculated as follows; 11.76 x ln(serum creatinine) + 5.11 x ln(serum total bilirubin) + 9.44. We compared the long-term outcomes between the high (≥10.4) and the low (<10.4) score groups. The cutoff value of MELD-XI score was determined based on the survival classification and regression tree (CART) analysis. The major adverse cardiac event (MACE) was defined as a composite of cardiac death, HF hospitalization, and lethal ventricular arrhythmias. During a mean follow-up period of 8.6 years (interquartile range 4.4-11.4 years), MACE was noted in 51 patients, including HF hospitalization in 37, cardiac death in 8, and lethal ventricular arrhythmias in 6. In Kaplan-Meier analysis, the high score group had significantly worse MACE-free survival compared with the low score group (log-rank, P<0.001). Multivariable Cox regression analysis showed that the MELD-XI score remained a significant predictor of MACE (hazard ratio 1.36, confidence interval 1.17-1.58, P<0.001) even after adjusting for patient characteristics, such as sex, functional status, estimated glomerular filtration rate, and cardiac function. Furthermore, CART analysis revealed that the MELD-XI score was the most important variable for predicting MACE. These results demonstrate that the MELD-XI score can effectively predict MACE in ACHD patients, indicating that ACHD patients with high MELD-XI score need to be closely followed.

[Splenic Injury during Replacement of the Thoracoabdominal Aorta].

Extraperitoneal approach is commonly employed for thoracoabdominal aortic repair via Stoney incision. It is supposedly rare to encounter abdominal visceral bleeding during that procedure. However, the spleen may spontaneously adhere to the adjacent peritoneum, which could induce incidental injury to the spleen by its anterior mobilization during extraperitoneal approach. Unless we bare its potential risk in mind, bleeding from the spleen may be overlooked, which results in hemodynamic deterioration. We have experienced 3 cases of splenic injury that necessitated hemostatic maneuvers for bleeding during and just after the thoracoabdominal aortic repair.

Concomitant Valve-Sparing Aortic Root Replacement With Repair of Tetralogy of Fallot.

Valve-sparing aortic root replacement is one of the effective repairs for aortic regurgitation resulting from progressive dilatation of the aortic root late after surgical correction of conotruncal anomaly. However, feasibility and effectiveness of this procedure are unknown for unrepaired physiology. A 32-year-old man presented with unrepaired tetralogy of Fallot (TOF) and moderate aortic regurgitation with severe left ventricular dysfunction. Valve-sparing aortic root replacement and TOF repair were simultaneously performed. Six months after the surgical procedure, aortic regurgitation remained trivial. Concomitant valve-sparing aortic root replacement with TOF repair can be feasible and effective for unrepaired TOF with aortic regurgitation.

Differential selective hypothermic intercostal artery perfusion: a new method to probe spinal cord perfusion during thoracoabdominal aortic aneurysm repair.

OBJECTIVE: To prevent paraplegia in patients undergoing thoracoabdominal aortic aneurysm repair, the importance of preoperative identification of the Adamkiewicz artery and reconstruction of critical intercostal artery have been advocated. Conversely, significance of collateral network for spinal cord perfusion has been recognized. We invented a new system consisting of a direct monitoring of cerebrospinal fluid temperature (CSFT) and differential selective hypothermic intercostal artery perfusion (D-HIAP). METHODS: After exposing a critical intercostal artery, a 10-mm prosthetic graft was anastomosed in an end to side fashion. A balloon-tipped catheter was inserted into the graft to perfuse with 15 °C blood. Neighboring intercostal arteries were also perfused in the same fashion. Serial monitoring of CSFT was performed. Between January 2011 and January 2015, D-HIAP was employed in 50 patients with Adamkiewicz artery that located within a reconstructed area. RESULTS: Significant CSFT drop was recorded after initiation of D-HIAP in 42 (84%) patients. Of those, 34 (68%) patients showed significantly lowered CSFT with D-HIAP into a single critical intercostal artery. Perfusion into plural intercostal arteries was necessary for CSFT drop in 2 cases (4%), and plural intercostal artery perfusion further enhanced CSFT drop that had been modestly achieved by single intercostal artery perfusion in 6 cases (12%). Eight (16%) patients did not exhibit a significant drop in CSFT even when D-HIAP was employed for the critical and neighboring intercostal arteries. CONCLUSIONS: The detection of a disparity in temperature between the intrathecal space and blood generated by D-HIAP revealed individual variability in CSFT changes, which may imply a complexity in spinal cord perfusion. Intraoperative D-HIAP may help to identify a major blood supply for spinal cord perfusion and underlying collateral network.

Prognostic Significance of PR Interval Prolongation in Adult Patients With Total Correction of Tetralogy of Fallot.

BACKGROUND: Several studies have demonstrated the importance of mechanoelectrical interaction in patients with surgically corrected tetralogy of Fallot. However, the significance of atrioventricular conduction disturbance, that is PR interval prolongation, on adverse cardiac events in those patients remains to be elucidated. METHODS: We examined electrocardiograms at baseline and their temporal change in a total of 176 patients with repaired tetralogy of Fallot (49% men; median age, 17.4 years). Then, we evaluated their correlation with right ventricular volume and function measured by cardiac magnetic resonance and the significance as a risk factor of adverse cardiac events: lethal ventricular arrhythmias, atrial arrhythmias, heart failure hospitalization, complete atrioventricular block (AVB), and all-cause death. RESULTS: First-degree AVB was noted in 25 patients (14%). During a median follow-up of 10.0 (5.0-14.2) years, there was a progressive prolongation of PR interval (2.00±3.99 ms/y). Importantly, there were significant correlations between PR interval prolongation and right ventricular enlargement or right ventricular dysfunction. In contrast, in patients who underwent pulmonary valve replacement (n=23), significant shortening of PR interval by pulmonary valve replacement was noted (204±32 versus 176±34 ms; P=0.007). Cox regression analysis showed that first-degree AVB was an independent risk factor for lethal ventricular arrhythmias (hazard ratio, 5.479; 95% CI, 1.181-25.42; P=0.030) and complete AVB (hazard ratio, 27.67; 95% CI, 4.152-184.3; P<0.001) and had a tendency for heart failure hospitalization (hazard ratio, 3.301; 95% CI, 0.864-11.80; P=0.069). In addition, PR interval prolongation >2 ms/y was also a significant risk factor for lethal ventricular arrhythmias, regardless of the presence or absence of first-degree AVB at enrollment (hazard ratio, 24.18; 95% CI, 2.080-281.1; P=0.011). CONCLUSIONS: These results indicate that progressive atrioventricular conduction disturbance is correlated with right ventricular enlargement and could be a useful predictor for increased risk of lethal ventricular arrhythmias in patients with repaired tetralogy of Fallot.

Effects of Hepatitis C Virus Antibody-Positivity on Cardiac Function and Long-Term Prognosis in Patients With Adult Congenital Heart Disease.

It was reported that hepatitis C virus (HCV) antibody-positivity adversely affects cardiac function. As the screening for HCV began in 1992, we hypothesized that HCV antibody-positive rate would be high in adult congenital heart disease (ACHD) patients who underwent heart surgery before 1992 and adversely affected cardiac function and long-term prognosis. We retrospectively enrolled 243 ACHD patients (mean age 25.9 years) who underwent cardiac surgery before 1992 and visited our hospital from 1995 to 2015. We compared clinical characteristics including cardiac function and long-term prognosis between HCV antibody-positive (n = 48) and antibody-negative (n = 195) patients. The composite end point (CEP) included cardiac death, heart failure hospitalization, lethal ventricular arrhythmias, and cardiac reoperation. The prevalence of reduced systemic ventricular ejection fraction <50% was significantly higher in the HCV antibody-positive group compared with the HCV antibody-negative group (17 vs 5.4%, p = 0.014). During a mean follow-up period of 10.1 years (interquartile range 6 to 14 years), the CEP was noted in 51 patients. Kaplan-Meier analysis showed the HCV antibody-positive group had significantly poor event-free survival than the HCV antibody-negative group (log-rank, p = 0.002). In contrast, HCV ribonucleic acid-positivity was not a significant predictor of the CEP in the HCV antibody-positive group (log-rank, p = 0.442). Furthermore, the HCV antibody-positivity was significantly associated with the CEP in both univariable and multivariable Cox regression models (hazard ratio 2.37, 95% confident interval 1.32 to 4.15, p = 0.005 and 1.96, 1.06 to 3.63, p = 0.032, respectively). In conclusion, these results suggest that more attention should be paid to HCV antibody-positivity in the management of ACHD patients.

Morphometrical and biomechanical analyses of a stentless bioprosthetic valve: an implication to avoid potential primary tissue failure.

OBJECTIVES: Stentless bioprosthetic valves provide hemodynamic advantages over stented valves as well as excellent durability. However, some primary tissue failures in bioprostheses have been reported. This study was conducted to evaluate the morphometrical and biomechanical properties of the stentless Medtronic Freestyle™ aortic root bioprosthesis, to identify any arising problem areas, and to speculate on a potential solution. METHODS: The three-dimensional heterogeneity of the stentless bioprosthesis wall was investigated using computed tomography. The ascending aorta and the right, left, and non-coronary sinuses of Valsalva were resected and examined by an indentation test to evaluate their biomechanical properties. RESULTS: The non-coronary sinus of Valsalva was significantly thinner than the right sinus of Valsalva (p < 0.01). Young's modulus, calculated as an indicator of elasticity, was significantly greater at the non-coronary sinus of Valsalva (430.7 ± 374.2 kPa) than at either the left (190.6 ± 70.6 kPa, p < 0.01) or right sinuses of Valsalva (240.0 ± 56.5 kPa, p < 0.05). CONCLUSIONS: Based on the morphometrical and biomechanical analyses of the stentless bioprosthesis, we demonstrated that there are differences in wall thickness and elasticity between each sinus of Valsalva. These differences suggest that the non-coronary sinus of Valsalva is the most vulnerable and at greater risk of tissue failure. The exclusion of the non-coronary sinus of Valsalva may be beneficial to mitigate the long-term risks of tissue failure in the stentless bioprosthesis.

Association between the severity of acquired von Willebrand syndrome and gastrointestinal bleeding after continuous-flow left ventricular assist device implantation.

OBJECTIVES: Acquired von Willebrand syndrome, characterized by the reduction in von Willebrand factor (vWF) large multimers, has recently been considered as one of the causes of gastrointestinal bleeding (GIB). It remains unclear whether its haematological severity is linked with susceptibility to bleeding because the definition of the haematological severity of acquired von Willebrand syndrome has not been precisely determined. This study sought to establish a quantitative methodology to assess the haematological severity of acquired von Willebrand syndrome and to define the threshold for occurrence of GIB in patients implanted with left ventricular assist devices (LVADs). METHODS: In total, 41 patients treated with continuous-flow LVAD implanted between 2011 and 2017 at Tohoku University Hospital were investigated. vWF large multimers were quantitatively evaluated using the 'vWF large multimer index' defined as the ratio of a large multimer proportion in total vWF derived from a patient to that from a normal control. Using this index, the amount of vWF large multimers was expressed as a percentage of its normal control value obtained with a simultaneous analysis of each time measurement. RESULTS: Twelve (29%) patients developed GIB events during follow-up periods (median 591 days) after an LVAD implantation. The vWF large multimer index in patients with GIB was significantly lower than that in those without GIB (25.0 ± 10.3% vs 37.5 ± 17.8%, P = 0.008). Most importantly, all patients experiencing GIB exhibited a vWF large multimer index below 40%. CONCLUSIONS: Patients with GIB exhibited a more severe loss of vWF large multimers. The vWF large multimer index may dictate the risk of GIB after an LVAD implantation. Clinical trial registration number: UMIN000018135.