[Coronary Artery Fistula with Aortic Valve Stenosis:Report of a Case].

A coronary artery fistula usually originates in the right coronary artery and often opens into the right ventricle. In approximately 50% of cases with a main pulmonary artery opening, aberrant blood vessels originate from both coronary arteries. Only a few cases of both coronary and bronchial artery-pulmonary artery fistulas have been reported. The patient was an 83-year-old man. Echocardiography showed severe aortic stenosis, while coronary angiography revealed aberrant vessels from both coronary arteries to the pulmonary artery. The right heart catheterization revealed a 26% left-to-right shunt ratio and a pulmonary/body blood flow ratio (Qp/Qs) of 1.36. MDCT scan confirmed that the aberrant vascular plexus originating from both coronary arteries was connected to the bronchial artery. We performed surgery on the patient, replacing the aortic valve and resecting the coronary arteriovenous fistulas. On the 11th postoperative day, the shunt had disappeared, as evidenced by a 1.2% left-toright shunt ratio and a Qp/Qs of the right heart catheterization of 1.02. The patient progressed uneventfully and was discharged on the 25th postoperative day.

Fibroblasts are the most suitable cell source for regenerative medicine due to their high intracellular fibroblast growth factor 2 content.

In our previous study, we found that dry-preserved multilayered fibroblast cell sheets promoted angiogenesis and wound healing in a mouse ulcer model by releasing high levels of intracellular fibroblast growth factor 2 (FGF2), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF), from dried cells. In the present study, to identify which cell types are suitable for human dry-preserved cell sheets (dry sheets), we compared the intracellular FGF2 levels in seven types of cells reported as cell sheets for clinical use or preclinical studies. FGF2 levels were high in mesenchymal cells, including human oral fibroblasts (HOFs) and human dermal fibroblasts (HDFs), human dental pulp stem cells (DPSCs), and human mesenchymal stem cells (MSCs); in contrast, FGF2 levels in human umbilical vascular endothelial cells (HUVECs), human skeletal muscle myoblasts (SkMMs), and human epidermal keratinocytes (HEKs) were remarkably low, approximately 25% those in fibroblasts. In addition, we prepared dry sheets from HOFs, DPSCs, and MSCs, and analyzed the growth factors released from each dry sheet upon rehydration. High levels of FGF2, HGF, and VEGF were detected in the eluate prepared by immersing each dry sheet. In particular, FGF2 and HGF were the most abundant in HOFs. An in vitro cell proliferation assay showed that these eluates significantly enhanced HUVEC proliferation compared to control cells. Furthermore, cells incubated with HOF eluate showed significantly higher cell proliferation than cells incubated with DPSC and MSC eluates. However, this proliferative response was significantly blocked by FGF2-neutralizing antibodies. These results demonstrate that growth factors released from human dry sheets have physiological activity and that this activity is mainly mediated by the effect of FGF2. Fibroblasts are ideal for the clinical application of dry-preserved cell sheets in humans owing to their high intracellular FGF2 content, fast cell proliferation, ease of handling, availability, and low culture costs, making them the most suitable cell source for regenerative medicine, with FGF2 release as the mechanism of action.

Dry preserved multilayered fibroblast cell sheets are a new manageable tool for regenerative medicine to promote wound healing.

This study investigated the therapeutic effects of dry-preserved multi-layered fibroblast cell sheets (dry sheets) on cutaneous ulcers. Dry sheets were prepared by air-drying multi-layered fibroblast cell sheets (living sheets) to cease their life activities. Before in vivo application, we tested the release of growth factors into the medium to examine the mechanisms of dry sheets in wound healing. Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were released from both dry and living sheets, while high levels of fibroblast growth factor-2 (FGF-2) and high mobility group box 1 (HMGB1) protein were only from dry sheets. An in vitro fibroblast proliferation assay revealed that the dry sheet eluate significantly enhanced cell proliferation and VEGF and HGF production compared with living sheet eluate. FGF-2-neutralizing antibodies significantly blocked this proliferative response. In wounds created on diabetic mice, the dry sheet-treatment groups using autologous or allogeneic cells showed significantly accelerated wound closure compared with that in the no-treatment group. The storage stability of the dry sheet was better at refrigeration temperature than at room temperature and remained stable for at least 4 weeks. Our data indicated that allogeneic dry sheets represent a promising new tool for regenerative medicine that promotes wound healing.

Fate of dissected arch vessels by adventitial inversion technique for acute type A aortic dissection repair.

OBJECTIVES: The adventitial inversion technique is used widely for aortic reconstruction for acute type A aortic dissection, as it easily controls the bleeding at anastomotic sites and closes the patent false lumen. However, this technique for arch vessel reconstruction has not been previously reported. Therefore, we applied the adventitial inversion technique for dissected arch vessel reconstruction to close the patent false lumen. METHODS: Among 57 consecutive patients who underwent emergency surgical treatment for acute type A aortic dissection from July 2006 to July 2012, the adventitial inversion technique for the dissected arch vessels was performed in 26 patients (42 arch vessel stumps). The patency and morphologic change of the false lumen of the arch vessels were evaluated using contrast-enhanced computed tomography. RESULTS: Overall, 2 hospital deaths were recorded, and the hospital mortality rate was 4%. No postoperative cerebral strokes and reoperations due to bleeding occurred. Follow-up by contrast-enhanced computed tomography was completed in 24 patients (37 stumps) with a mean duration of 99 ± 35 months. The postoperative closure rate of the false lumen after adventitial inversion was 86%, which was higher than when adventitial inversion was not used. No adverse events including stroke occurred during follow-up period. CONCLUSIONS: This technique facilitates the closure of the false lumen of dissected arch vessels and might improve clinical outcomes.

Intimal-protected adventitial inversion technique accelerates the obliteration of a patent false lumen.

BACKGROUND AND AIMS: The optimal procedure for reconstructing the dissected aortic stump for acute type A dissection remains controversial. We routinely used the intimal-protected adventitial inversion technique (iPAIT), a modified adventitial inversion technique, to protect the fragile intima by inserting a graft and assessed the safety and efficacy of this technique. METHODS: Between August 2008 and April 2020, 146 consecutive patients with acute type A dissections underwent thoracic aortic surgery in our hospital. Extended total aortic arch replacement was performed in 119 patients (81.5%). Sixty-nine patients underwent treatment for distal aortic anastomosis with the iPAIT. To compare the iPAIT to a historical control, we assessed 69 iPAIT patients and 25 patients who underwent total arch replacement using gelatin-resorcinol-formaldehyde (GRF) glue. RESULTS: Hospital mortality was 2.9% in the iPAIT group and 8.0% in the GRF group. Perioperative characteristics were similar between the two groups. However, postoperative computed tomography revealed that the obliteration rate was significantly higher in the iPAIT group (60/66, 90.9%) than in the GRF group (15/23, 65.2%) (p = .01), not including the patients who had died or developed severe renal dysfunction. The 8-year aortic event-free survival rate in the iPAIT group (81.3%) was significantly higher than that in the GRF group (47.4%). CONCLUSIONS: The use of this technique for acute type A dissections resulted in a low mortality rate and demonstrated promising midterm survival and may accelerate the obliteration of a patent false lumen and prevent late aortic events.

Feasibility of open chest management with modified negative pressure wound therapy immediately after cardiac surgery.

OBJECTIVES: To evaluate the feasibility of open chest management with our modified negative pressure wound therapy immediately after cardiac surgery as a therapy for atypical tamponade. METHODS: Open chest with modified negative pressure wound therapy was performed immediately after cardiac surgery. The surface of the heart and the vessels were covered with non-adherent siliconized gauze. The sternal halves were stented using edge-cut disposable syringes to maintain a larger mediastinal cavity. Approximately 45 mm of distance was kept between the sternal edges. A trimmed sterile polyvinyl foam sponge was inserted into the mediastinum, the entire wound was sealed and negative pressure (-50 to -75 mmHg) was applied using a suction generator. Delayed chest closure was performed in a standard manner once the haemodynamic status was stabilizsed. RESULTS: The mortality rate was 3/15 (20%) patients. Deep sternal wound infection occurred in 1/15 (6.7%) patients. Five patients were extubated during the open chest management. Sternal closure was delayed for median of 3 days after the initial surgery. There was no incidence of bleeding complications or need for additional haemostatic procedures. CONCLUSIONS: Negative pressure wound therapy performed immediately after cardiac surgery was feasible in our small number of patients. CLINICAL REGISTRATION NUMBER: Study ID: 2020-149.

Validity of direct bilateral axillary arterial cannulation in emergency surgery for acute type A aortic dissection.

BACKGROUND AND AIM OF THE STUDY: To assess the validity and long-term outcomes of direct bilateral axillary arterial cannulation for acute type A aortic dissection. METHODS: Between 2003 and 2020, 208 consecutive patients with acute type A aortic dissection underwent emergency surgical repair. Cardiopulmonary bypass was attempted to establish direct bilateral axillary arterial cannulation and bicaval drainage. Antegrade selective cerebral perfusion was established by axillary perfusion and direct cannulation of the left common carotid artery. RESULTS: Ascending aortic, partial arch, and extended total aortic arch replacement were performed in 50 (24.0%), 7 (3.4%), and 151 (72.6%) patients, respectively. Aortic root surgery and coronary artery bypass grafting were performed concomitantly in 23 and seven patients, respectively. Cardiopulmonary bypass was attempted only through bilateral axillary cannulation in all patients but was successful in 13 (6.3%) patients without bilateral axillary cannulation. No postoperative complications occurred related to this technique. There were seven hospital deaths (early mortality rate, 3.4%). Five patients had postoperative reoperation for bleeding, and nine (4.3%) were transferred to other hospitals due to postoperative permanent cerebral infarction, particularly two with arm ischemia. The 10-year survival rate of patients who underwent emergency surgical repair with this technique was 71.4%. CONCLUSIONS: Direct bilateral axillary arterial cannulation followed by selective cerebral perfusion was successful in 93.7% of patients and this may be an optimal solution for providing stable outcomes after emergency surgery for acute type A aortic dissection. However, we experienced two complications of arm ischemia, attention should be paid to potential arm ischemia.

Freezing of cell sheets using a 3D freezer produces high cell viability after thawing.

In cell therapy, transplanting an appropriate number of cells to the target site is crucial. One way to achieve this is to transplant cell sheets. Transplantation of cell sheets has already been utilized for various diseases in clinical practice. However, reducing the cost of cell sheet utilization is essential so as to facilitate the spread of regenerative medicine. Several ways to reduce costs are available, one of which is the use of allogenic cells. Another alternative is the use of cell sheets, which necessitates the development of methods for freezing cell sheets. This is the first study to report the use of a 3D Freezer for freezing cells. 3D Freezers have been used in the field of food processing and technology for a long time. The 3D Freezer freezes objects using cold air at a uniform temperature from all directions. In this study, we analyzed the cooling speed of human fibroblast sheets in 11 cell preservation solutions using a 3D Freezer and a Program Freezer. The cooling speed was -2 °C per min in the 3D Freezer. Supercooling in 10 cell preservation solutions was lower in the 3D Freezer than in the Program Freezer. Cell viability after freeze-thaw of the cell sheets using 3D Freezer was more than 70% in five cell preservation solutions. The levels of hepatocyte growth factor and transforming growth factor-ß1 were the same not only in the fibroblast sheets frozen using the five cell preservation solutions but also in the non-frozen fibroblast sheets. These results suggest that the 3D Freezer can freeze implantable cell sheets immediately after thawing.

[Re-operation with Infarct Exclusion Technique due to Residual Shunt after Extended Sandwich Patch Technique for Postinfarction Ventricular Septal Perforation:Report of a Case].

We report a case in which infarct exclusion technique was used to repair residual shunt after extended sandwich patch technique for postinfarction ventricular septal perforation (VSP). A 76-yearold woman was diagnosed with postinfarction VSP and underwent extended sandwich patch technique through right ventriculotomy on the third day after the onset of VSP. No residual shunt was then observed by intraoperative transesophageal echocardiography, but a slight residual shunt was observed on the 7th day after operation. She had no symptom of cardiac failure, and was followed up. However, the residual shunt worsened, and she developed cardiac failure on the 48th day after the initial operation. An additional operation by infarct exclusion technique was performed. No residual shunt was observed after the additional operation. She has been doing well with no signs of cardiac failure.

[Transmitral Septal Myectomy and Mitral Valve Plasty for Hypertrophic Obstructive Cardiomyopathy Combined with Organic Mitral Regurgitation;Report of a Case].

A 60-year-old man with hypertrophic obstructive cardiomyopathy (HOCM) combined with organic mitral regurgitation underwent transmitral septal myectomy and mitral valve plasty. Although a transaortic septal myectomy (Morrow's procedure) is generally accepted as the standard surgical treatment for HOCM, it may be difficult to perform sufficient septal myectomy for mid-ventricular obstructive hypertrophic cardiomyopathy and apical hypertrophic cardiomyopathy (HCM). The transmitral approach with temporary detachment of the anterior mitral leaflet provides a good surgical view in the left ventricle, which allows sufficient septal myectomy from the outflow tract to the apex.

Preserving the endothelium in saphenous vein graft with both conventional and no-touch preparation.

BACKGROUND: Despite the inferior patency compared to arterial grafts, a saphenous vein graft (SVG) is widely used for coronary artery bypass grafting (CABG). A lower atherosclerosis rate and higher patency have been reported for SVG obtained via the no-touch technique (NT) than via conventional preparation (CV). Although CV-mediated endothelial dysfunction is implied, the precise mechanism underlying the higher patency with NT is poorly understood. METHODS: Human residual SVGs during CABG and SVG sections after autopsy were analyzed. The endothelial surface was observed using scanning electron microscopy (SEM) and blindly compared between CV and NT. The endothelial integrity was also analyzed with immunohistochemistry. RESULTS: Unexpectedly, the hyperfine structure on SEM was comparable between CV and NT before grafting, and microvillus, a characteristic of endothelium, was indistinguishable between them. Von Willebrand Factor, an endothelial marker, was equally detected throughout the vascular wall in both groups from residual and postmortem sections. CONCLUSIONS: The morphological integrity of the endothelium was successfully preserved in SVG with CV, even at an ultrastructural level. Although its functionality remains to be addressed, other factors than the endothelium may be involved in the high patency obtained by NT. The present findings suggest that the characteristics of NT and surgical methodology should be reconsidered.

Impact of acute kidney injury on prognosis of chronic kidney disease after aortic arch surgery.

OBJECTIVES: Postoperative acute kidney injury (AKI) is a common complication associated with increased long-term mortality after cardiothoracic surgery. However, AKI after total aortic arch replacement (TAR) is not well studied. This study aimed to investigate the prognosis and impact of AKI on the long-term outcomes of chronic kidney disease (CKD) patients undergoing TAR. METHODS: We included 208 patients who underwent TAR between September 2003 and December 2014. Patients were divided into a CKD (n = 83, 40%) and non-CKD (n = 125, 60%) group. The definition of AKI followed the Risk, Injury, Failure, Loss of kidney function and End-stage kidney disease (RIFLE) criteria. Independent risk factors for all-cause death and AKI were identified with multivariable analysis. RESULTS: Postoperative AKI was observed in 24 patients (29%) and 39 patients (31%) of CKD and non-CKD groups, respectively. The survival rate of CKD patients was significantly lower than that of non-CKD patients (P = 0.02). Among CKD patients, the 5-year survival rate was 57% in those with AKI group and 92% in those without AKI; prognosis was significantly poorer in patients with AKI (P = 0.001). In the non-CKD group, there was no difference in prognosis between patients with or without AKI (P = 0.77). Multivariable logistic regression analysis revealed that intraoperative blood loss of ≥600 ml was the only predictor of AKI in the CKD group (odds ratio 4.32, P = 0.04). CONCLUSIONS: CKD is associated with reduced long-term survival after TAR. Postoperative AKI strongly influences long-term survival in CKD patients only.

Midterm Outcomes of Endovascular Aortic Aneurysm Repair with Carbon Dioxide-Guided Angiography.

BACKGROUND: Although iodinated contrast (IC) agents are commonly used in endovascular aneurysm repair (EVAR), perioperative use in patients with renal dysfunction or IC allergies is avoided. Carbon dioxide (CO2)-guided angiography is a promising alternative. We aimed to evaluate short-term and midterm outcomes of EVAR using CO2-guided angiography. METHODS: Three hundred eighty-one patients who underwent EVAR from January 2012 to September 2016 were retrospectively reviewed and divided into an IC-EVAR group (n = 351) and CO2-EVAR group (n = 30). Subjects in the CO2-EVAR group had severe renal dysfunction (n = 27) and IC allergy (n = 4). Intraoperative, postoperative, and follow-up variables were compared. RESULTS: Compared with the IC-EVAR group, preoperative serum creatinine level was significantly higher (2.0 vs. 0.92 mg/dL, P < 0.0001) and mean IC dose was significantly lower (18 vs. 55 mL, P < 0.0001) in the CO2-EVAR group. The fluoroscopy time, operative time, number of stent grafts placed, and technical success rates of the groups were similar; no type I and/or type III endoleaks were detected on completion angiography. There was no acute kidney injury and one case of intestinal necrosis in the CO2-EVAR group, potentially due to cholesterol embolism. Postoperative endoleak, enlargement of aneurysms, survival, freedom from secondary intervention, and renal function change up to 3 months, postoperatively, were similar between the groups. CONCLUSIONS: CO2-EVAR is technically feasible and exhibits prominent renal protection. However, consideration of the aortic lumen status remains an important challenge.