Body mass index as a tool for optimizing surgical care in coronary artery bypass grafting through understanding risks of specific complications.

OBJECTIVES: To investigate the relationship between body mass index (BMI) and early outcomes, and specific types of morbidities associated with low and high BMI, in patients undergoing coronary artery bypass grafting. METHODS: This was a retrospective study on isolated coronary artery bypass grafting patients (aged ≥60 years) between 2008 and 2017 in the Japan Cardiovascular Surgery Database. The primary end point was defined as operative mortality. The secondary end point was combined morbidity (ie, operative mortality, reoperation for bleeding, stroke, new onset of hemodialysis, mediastinitis, and prolonged ventilation). Patient characteristics and outcomes were compared among BMI groups. Spline curves were fit between BMI and outcomes. Multivariable logistic regression models with categorized BMI and generalized additive models with spline-transformed BMI were used to estimate and visualize the effect of BMI adjusted for other covariates. RESULTS: A total of 96,058 patients were included in the analysis. Low (<18.5) and high (≥30) BMI were both associated with a higher risk of mortality (low: adjusted odds ratio, 1.34; 95% confidence interval, 1.16-1.54; P < .0001, and high: adjusted odds ratio, 2.10; 95% confidence interval, 1.70-2.59; P < .0001) and combined morbidity (low: adjusted odds ratio, 1.18; 95% confidence interval, 1.08-1.29; P = .0002 and high: adjusted odds ratio, 1.82; 95% confidence interval, 1.63-2.03; P < .0001). Low and high BMI were associated with different types of morbidities. In models using spline transformation, the deviation of BMI from a proximately 21 to 23 was proportionally associated with increased risk. CONCLUSIONS: In patients undergoing coronary artery bypass grafting, low and high BMI were risk factors of mortality associated with different types of morbidities, which may warrant tailored preventive approaches.

Acute type B aortic dissection with communicating vs. non-communicating false lumen.

BACKGROUND: In practice, patients with acute aortic dissection (AAD) are generally divided into 2 groups according to the status of the false lumen: non-communicating or communicating. The similarities and differences between the 2 groups, however, have not been fully determined in a large population. METHODS AND RESULTS: We studied 502 patients with Stanford type B AAD. Clinical background at symptom onset was compared, and similarities and differences characterized, for patients with non-communicating (NC group, n=288) vs. communicating (C group, n=214) false lumens. Time of day (00.00-06.00 hours, 06.00-12.00 hours, 12.00-18.00 hours, and 18.00-24.00 hours) and extent of physical activity (extreme exertion, slight exertion, at rest, and sleeping) at symptom onset were similar between groups. Patients in the NC group were older (mean age, 71±11 years vs. 64±14 years, P<0.01) and had lower prevalence of distally extended aortic dissection (26% vs. 8%, P<0.01) and deaths in hospital (2% vs. 7%, P=0.011) than those in the C group. CONCLUSIONS: At symptom onset, clinical circumstances and physical activity were similar between the groups, and old age and a background of DeBakey IIIa aortic dissection may be associated with determination of false lumen status. The outcome in the NC group was better than in the C group.

Novel infectious agent-free hemostatic material (TDM-621) in cardiovascular surgery.

SUBJECTS: Currently, hemostatic materials made from human blood components and animal-derived collagen is used for controlling operative hemorrhage in the cardiovascular surgery field. In this study, we focused on an entirely synthetic self-assembling peptide (development code: TDM-621) that gels when in contact with blood or other bodily fluids and stops bleeding upon contact with a wound site. We investigated its usefulness as a hemostatic material in animal and clinical studies. METHODS: Before we began the clinical study, we demonstrated the hemostasis efficacy and safety of TDM-621 in animal experimental models. Twenty-five patients (22 men, 3 women) were enrolled in the clinical study, and the following procedures were performed: 1) coronary artery bypass graft (CABG) (n = 9), 2) abdominal aortic graft replacement (n = 4), and 3) peripheral artery bypass (n = 12). The TDM-621 material was applied to a total of 33 vascular anastomotic graft sites (some patients received material at more than one site). Both hemostatic efficacy and safety were examined. RESULTS: A total of 33 anastomotic graft sites in 25 patients were evaluated, and the averaged primary and secondary efficacy rate was 94.5%. No postoperative bleeding or adverse events (including serious adverse events) with a causal relationship to treatment were observed. CONCLUSION: This study indicated that TDM-621 is a more effective and reliable hemostat than commonly-used general hemostatic agents and, therefore, will be very useful in several cardiovascular surgery applications.

Bidirectional Glenn procedure for an infected modified Blalock-Taussig shunt.

A 1-month-old girl underwent right modified Blalock-Taussig shunt (mBTS) for pulmonary atresia with hypoplastic right ventricle. Five months after palliation, she suffered from sepsis and progressive desaturation following otitis media. Computed tomography and angiography revealed a pseudoaneurysm surrounding the mBTS graft. After stabilization of the infection, we performed pseudoaneurysm resection, shunt-graft removal, and the bidirectional Glenn (BDG) procedure under cardiopulmonary bypass. Her condition improved, and she was discharged on the 17th day after surgery. When parameters for the partial right heart bypass should permit, the BDG procedure can be a beneficial recovery procedure for the cases of infected pseudoaneurysm after mBTS in Fontan candidates.

Antibiotics and Drainage for Treating Stent-Graft Infection after EVAR.

The patient was a 64-year-old man. He developed fever and lumbago 6 months after the EVAR. Because CT showed an abscess in the aortic aneurysm surrounding the stent graft, stent-graft infection was diagnosed, and treatment with intravenous antibiotics was initiated. However, the fever and inflammatory markers persisted; therefore, CT-guided drainage catheter placement was performed. After all the pus had been discharged, the fever subsided, and the inflammatory reaction was also suppressed. One year has elapsed since the treatment, and the patient continues to visit with no complaints. We report that stent-graft infection was relieved with antibiotics and drainage.

Fontan conversion with novel direct ablation after childbirth: report of a case.

A 38-year-old woman underwent atriopulmonary Fontan surgery at age 18 years and subsequently successfully delivered a girl by cesarean section at age 34. Her condition later deteriorated due to atrial tachyarrhythmia and progressed to New York Heart Association (NYHA) class IV heart failure. Her treatment, at age 36, comprised total cavopulmonary connection conversion, direct right atrial ablation with bipolar radiofrequency devices, the creation of an atrial septal defect, and placement of a dual-chamber permanent pacemaker. Three years after the conversion, her condition has improved to NYHA class I.

Optimal culture conditions for constructing durable biografts for repairing the impaired heart--dynamic cell culture with pre-seeding.

BACKGROUND: Tissue engineering with cell seeded biodegradable material has attracted attention as a novel means of treating the severely impaired heart. Here, we consider optimal preparation of a durable biograft using dynamic and static cultures. METHODS: Vascular smooth muscle cells (VSMCs) derived from the rat aorta were seeded onto biodegradable material P (LA/CL) (poly-L-lactide-ε-caprolactone copolymer) and cultured as follows: a) Static culture (n = 11), b) dynamic culture (n = 12), c) 0 h pre-seeding (n = 12), d) 24 h pre-seeding (n = 5) and e) 1 week pre-seeding (n = 12). Dynamic culture: Cells were cultured in spinner flasks. Pre-seeding: Static cell seeding and culture before dynamic culture. EVALUATION: The conditions of the P (LA/CL) in the five groups were evaluated as cell proliferation and by histological studies. RESULTS: VSMCs proliferated both in and on the biodegradable materials. The quality of the dynamic culture cell with pre-seeding increased. Although the duration of pre-seeding exerted no significantly different effects, cell attachment and proliferation were widely scattered in the 0 h pre-seeding group, whereas cells proliferating on the front of the scaffold obstructed proliferation inside the biodegradable material in the 1 week pre-seeding group . CONCLUSIONS: Dynamic cell culture with 24 h pre-seeding is effective for constructing ideal biografts.

Stent graft implantation combined with coil embolization and external-internal iliac artery bypass surgery: report of a case.

A 73-year-old male patient was found to have an abdominal aortic aneurysm complicated with bilateral common iliac artery aneurysms. He also had hepatitis C, chronic liver cirrhosis (Child-Pugh class B), a rupture of esophageal varices, hepatocellular carcinoma, and intractable ascites. The functions of other systemic organs were also impaired. We first performed a right internal iliac artery coil embolization prior to stent graft implantation combined with a left external-internal iliac artery bypass. These additional procedures allowed for safe treatment with stent graft implantation, without any serious complications.

Redo CABG for ACS via the left thoracotomy using the PAS-port system to the descending thoracic aorta: a case report.

A 74-year-old female patient with left main trunk (LMT) and triple vessel disease underwent coronary artery bypass graft (CABG) surgery. The patient began to experience exertional dyspnea. A coronary artery angiogram confirmed a severe stenosis in the proximal side of the saphenous vein graft (SVG). The patient had impending infarction immediately after the unsuccessful attempt for percutaneous coronary intervention, which resulted in an emergent CABG procedure. A left thoracotomy at the 4th intercostal space was made with the patient in the right lateral position. We then interrupted the use of intra-aortic balloon pumping (IABP), confirmed on transesophageal echocardiography (TEE) that the balloon was in a position distal to the target anastomosis site, and made a proximal anastomosis using the PAS-Port system (Cardica, Redwood City, CA, USA). After its successful deployment, IABP was repositioned back and resumed. The distal anastomosis was made to the previously bypassed graft. The patient had no postoperative myocardial damage or complications and was discharged on postoperative day 21. A redo CABG for post-CABG acute coronary syndrome patient was thought to be an extreme high risk; however, the operative time could be minimized by using the PAS-Port system, which enabled a safe redo CABG with left thoracotomy.

Effect of cryopreservation on cell proliferation and immunogenicity of transplanted human heart cells.

BACKGROUND: Cell preservation is essential for successful cell transplantation and/or tissue engineering. We examined the effects of cryopreservation on the transplantation of human heart cells. METHODS: Cells isolated from human atrial tissues were cultured for 15 days (control group), cryopreserved for 1 week, and rapidly thawed and cultured for 15 days. Proliferation was compared among control and cryopreserved cells or tissues by constructing growth curves. Growth factors, cytokines, biochemical features, and cell cycle phase were measured immediately before and after cryopreservation, and immunogenicity was evaluated from growth curves generated from heart cells after 7 days in mixed-lymphocyte culture. Control or cryopreserved cells were transplanted into rat connective tissues and evaluated histologically 2 weeks later. RESULTS: Cryopreserved cells proliferated more effectively than control cells. Levels of basic fibroblast growth factor and transforming growth factor-ß1 were significantly higher, and those of interleukin (IL)-6 and IL-8 were significantly lower after cryopreservation. Fewer peripheral blood lymphocytes were produced in cryopreserved cells than in noncryopreserved cells, and the cell cycle phase of cryopreserved heart cells shifted primarily to G2 + M from G1 + G0. Noncryopreserved and cryopreserved cells both survived in connective tissue. CONCLUSION: Human atrial cells can be cultured, cryopreserved, and transplanted. Cryopreservation might increase the proliferation of human cells and tissues and also reduce the immunogenicity of heart cells.

[Surgical repair of a total-defect aortopulmonary window in a neonate].

Aortopulmonary window (APW) is a rare congenital heart defect that requires urgent repair, as it can lead to rapid development of pulmonary hypertension. A 6-day-old boy with a total-defect APW was transferred to our hospital and underwent definitive repair on the 15th day after birth. The ascending aorta and pulmonary trunk were divided to create a larger tissue margin on the aortic side for the next seam. Then, the aortic window was sutured and closed directly, while the large pulmonary defect was reconstructed with a fresh autologous pericardial patch. Although peritoneal dialysis was briefly required for acute renal failure due to low output syndrome, his condition improved and he was discharged 22 days after surgery. Six years later, he remains well, without complications or need for medication.

Successful surgical repair of an infectious thoracic aortic pseudoaneurysm accompanied by aortobronchopulmonary fistula and advanced hepatic dysfunction without assisted circulation.

The patient was a 59-year-old female. Because of massive hemoptysis, she was brought to our emergency center by ambulance. Thoracic computed tomography led to a diagnosis of an infectious thoracic aortic pseudoaneurysm accompanied by an aortobronchopulmonary fistula. Emergency surgery followed. Also noted was an advanced hepatic dysfunction, assessed as Child-Pugh score B, caused by an alcoholic liver disease. A localized affected area made it possible for us to perform an aneurysmectomy using a temporary bypass rather than assisted circulation. A patch plasty using expanded polytetrafluoroethylene completed the procedure. Streptococcus agalactiae (GBS) was detected in a sample obtained during the surgery from an abscess located in the aneurysm. The patient made satisfactory postoperative progress and left the hospital walking unaided on the 36th postoperative day.

An aortic root pseudoaneurysm that developed after implantation of a rectus abdominis muscle flap to treat an MRSA mediastinitis: a case report.

The occurrence of mediastinitis following synthetic vascular replacement surgery is still associated with an unfavorable prognosis in the treatment of thoracic aortic diseases. This time we report a Bentall procedure that we re-performed to treat an aortic root pseudoaneurysm, which developed after a postoperative mediastinitis. This followed the first Bentall procedure, which was treated by debridement of the focus of infection, continuous lavage, and a two-step rectus abdominis muscle flap implantation. Implantation of a rectus abdominis muscle flap is effective in controlling infection in the treatment of mediastinitis after heart surgery. However, after synthetic vascular replacement surgeries have been performed to treat aortic diseases, especially after aortic root reconstruction surgery, which puts stress on the anastomotic site, consideration should be given regarding the development of hemorrhages and pseudoaneurysms as a result of infection-induced tissue fragilization.

Study of coronary artery bypass using the PAS-Port device: assessment by multidetector computed tomography.

OBJECTIVE: The use of automatic anastomotic devices in coronary artery bypass grafting surgery is associated with lower patency rates in comparison to conventional anastomosis methods. This is thought to be caused by graft curvature occurring after closing of the chest wall. METHODS: We evaluated 39 grafts in 28 patients who underwent off-pump coronary artery bypass surgery using the PAS-Port. After surgery, the proximal anastomotic angle of each stent, graft morphology, and patency were evaluated with axial and sagittal views. RESULTS: The angle for the left anterior descending coronary artery segment was relatively obtuse on the left side of the ascending aorta, and the graft loop formation was not necessary. The angle for the left circumflex coronary artery segment was significantly acute for anastomosis from the upper left side of the ascending aorta. Because grafts are under the constraints of a large loop, graft length tended to become easily excessive or deficient. The angle for the right coronary artery segment was relatively obtuse. The space on the right side of the heart was so narrow that in some cases we had difficulty setting out the appropriate graft location to prevent graft curvature. No bending or stenosis was present in any graft, showing a patency rate of 100%. CONCLUSION: The short-term results of coronary bypass grafting using PAS-Port are satisfactory.

Perception in relation to a potential influenza pandemic among healthcare workers in Japan: implications for preparedness.

Due to the potential for an influenza pandemic, preparedness for infection control in healthcare settings is essential from the standpoint of occupational health for healthcare workers. We conducted questionnaire surveys among Japanese hospitals to assess preparedness at the individual and institutional levels and their inter-relationship. Questionnaires were administered at 7 tertiary hospitals in Japan during the spring of 2006. We analyzed 7,378 individual responses of the 10,746 questionnaires administered and all seven institutional responses by hospital infection control committees. Healthcare workers assigned low importance to personal protective equipment and showed mixed attitudes (anxious but accepting) to the potential risk. Institutional gaps existed in preparedness across hospitals and most hospitals lacked the specificity to cope with a pandemic. A higher level of institutional preparedness, as determined by expertise as well as general and specific countermeasures, was an important predictor of individual recognition of preventive measures, perception of institutional measures, and attitude toward coping with risk. A higher level of institutional preparedness stood out to be an important predictor of individual preparedness. Considering the risk of a future influenza pandemic, hospitals should improve preparedness at all levels.

Usefulness of perioperative blood glucose control in patients undergoing off-pump coronary artery bypass grafting.

OBJECTIVE: We investigated the usefulness of perioperative blood glucose control in patients undergoing coronary artery bypass grafting (CABG). METHODS: DM patients were aggressively treated with intensive insulin therapy to achieve a preoperative fasting blood glucose level of 140 mg/dl and a postoperative level of 200 mg/dl. For comparison, patients were divided as follows: (1) DM group vs. non-DM group, and (2) for mean blood glucose level in the intensive care unit (ICU), lower than 200 mg/dl (IL) vs. 200 mg/dl or higher (IH). RESULTS: (1) In the DM group, the amount of insulin (U) used during surgery was greater (P<0.05), and the duration of ICU stay was longer (P<0.05). The incidence of all complications was higher in the DM group (P<0.05). (2) Between the IH group (54) and the IL group (82), the proportion of DM patients was higher in the IH group (75% vs. 38%, P<0.05). In the IH, the duration of ICU stay (P<0.01) was longer, and the incidence of all complications was higher (P<0.05). (3) In the DM group, the incidence of complications tended to be higher in the IH group. The incidence of complications was extremely low in the non-DM group. CONCLUSION: Strict perioperative blood glucose control may help to improve the outcomes of CABG.

[Effects on proliferation ability of vascular smooth muscle cells by static and/or dynamic cell culture: utility of pre-seeding technique for dynamic cell culture].

OBJECTIVES: Conventional biomaterials are not viable, do not grow, and do not provide contractile effects in cardiac tissue. Foreign synthetic material may become thrombogenic or infected. The most recent cardiac constructs consist of biodegradable material which has the potential to solve these problems. However, dynamic three-dimensional cell culture is necessary because conventional culture is limited to construct tough biografts. METHODS: Vascular smooth muscle cells derived from rat aorta were seeded to poly-L-lactide-epsilon-capro-lactone copolymer in three groups; static culture group (static cell seeding + static cell culture), dynamic culture group (dynamic cell seeding + dynamic cell culture), and pre-seeding group [static cell seeding and culture for 1 week (pre-seeding) + dynamic cell culture]. The dynamic cell culture system used an original spinner flask. The pre-seeding technique used static cell seeding and culture before dynamic culture. The three groups were evaluated by cell proliferation and histologic studies. RESULTS: Vascular smooth muscle cells could be proliferated in/on the biodegradable materials. The pre-seeding group cells grew much more efficiently than the other groups. Very few cells were found in the biodegradable materials with the dynamic groups. However, there were many cells in the materials with the static culture group and pre-seeding group, especially the pre-seeding group. CONCLUSIONS: Dynamic culture is useful for constructing tough biografts by the pre-seeding technique.

The variations in the immunologic features and interleukin-6 levels for the surgical treatment of cardiac myxomas.

PURPOSE: In this study, we propose the existence of a relationship between cardiac myxomas and the immunologic features or interleukin-6 (IL-6), while also considering the optimal treatment of cardiac myxoma, especially "familial myxoma." METHODS: In a 19-year period at our hospital, 20 patients underwent 21 operations for cardiac myxomas. The immunologic features and the IL-6 levels were measured pre-operatively in 13 cases and post-operatively in 10 cases. A case of "familial myxoma" was diagnosed based on molecular genetic analyses. RESULTS: No patients died in the hospital. The tumor size correlated with the preoperative IL-6 and/or alpha1-globulin values (P < 0.05). In addition, all of the immunologic features and IL-6 levels normalized by 4 weeks after surgery. "Familial myxoma" demonstrated recurrence without showing increases in either the immunologic features, inflammatory signs, or serum IL-6 levels. CONCLUSIONS: Patients with cardiac myxoma should therefore be operated on immediately because the possibility that the tumor size might be large when IL-6 and/or alpha1-globulin values are high. In addition, cases of "familial myxoma" require careful observation and periodic echocardiography after surgery to identify any possible recurrence. Recently, molecular genetic analyses are therefore considered to be an important diagnostic tool for cardiac myxoma, especially "familial myxoma." Our "familial myxoma" case demonstrated a C769T PRKAR1a mutation, which has also been observed in other cases of "familial myxoma."

Evaluation of bioprosthetic valve for small aortic root in elderly patients.

The hemodynamics of stentless bioprostheses are superior to those of mechanical valves, especially for patients with a small aortic root. Between March 1999 and July 2001, we implanted 18 Freestyle stentless porcine valves using our technique of repeated division of the space by halving the distance. Seven patients received 19-21-mm valves and 11 received 23-25-mm valves. Clinical data and early and midterm outcomes of both groups were compared. The mean preoperative echocardiography gradient of the small valve group was 84.7 mm Hg, and when discharged from hospital, the mean gradient was 14.8 mm Hg. One operative death was encountered due to arrhythmia. This stentless porcine prosthesis has excellent hemodynamics and can be implanted safely and easily, even in elderly patients with a small aortic root, using our suture technique.