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Original Article, Background: Approximately half of all patients requiring mechanical ventilation with endotracheal intubation develop swallowing problems after extubation. Swallowing can be examined in several ways, but the preferred clinical methods are videofluoroscopic examination of swallowing or other imaging methods, which allow visual detection of abnormal swallowing patterns. Unfortunately, these imaging techniques do not allow quantitative analysis. If a device could provide numerical values in evaluating swallowing capability, research could then collect useful data to help determine when to reintroduce oral intake of food and liquids and whether aspiration is likely during such intake. Evidence suggests a relationship between maximum tongue pressure and the ability to swallow correctly. We therefore evaluated changes in tongue pressure over time in patients who had just been extubated and investigated whether significant pressure differences existed between patients who later aspirated and those who did not. Methods: The participants were 36 patients who had received mechanical ventilation by means of endotracheal intubation. Maximum tongue pressure was measured repeatedly for 1 week after extubation. The values for participants who did and did not subsequently aspirate were then compared. Results: Post-extubation tongue pressure values were lower than normal in all patients, but they increased over time. However, values for patients who aspirated were significantly lower than those for patients who could swallow normally. Conclusion: The results suggest that tongue pressure is a useful test of post-extubation swallowing ability and that it can help determine when to restart oral intake of food and liquids and identify aspiration risk.

Purpose To determine whether a dynamic cultured biograft can positively affect the function of the damaged heart. Methods We ligated the coronary artery (LAD) of rats to generate a model of myocardial infarction (MI) and then implanted them with the following grafts comprising vascular smooth muscle cells (VSMCs) derived from the rat aorta and seeded onto biodegradable patches (patch replacement therapy; (PRTx)): control without PRTx, PRTx without seeded cells, PRTx with static cultured VSMCs, PRTx with dynamic cultured VSMCs and sham-operated. Cultured VSMCs were labeled with PKH26 for identification after implantation, and the centre of the MI site was excised and replaced with an implanted biograft. Cardiac performance was monitored for 12 weeks thereafter and followed by a histological study. Results Although the ejection fraction of the damaged heart improved in all groups that were transplanted with grafts, remodeling was prevented only in groups with a dynamic or static cultured patch. More cells were α-SMA-positive in the group with the dynamic, rather than the static cultured patch. Cells were positive for PKH26 in the biograft and in the infarcted myocardium. Conclusions Dynamic cultured biografts improved the function of the infarcted myocardium more than statically cultured biografts or those without cells.

Traumatic brain injury (TBI) is widely known to cause dynamic changes in cerebral blood flow (CBF). Ischemia is a common and deleterious secondary injury following TBI. Detecting early ischemia in TBI patients is important to prevent further advancement and deterioration of the brain tissue. The purpose of this study was to clarify the cerebral circulatory disturbance during the early phase and whether it can be used to predict patient outcome. A total of 90 patients with TBI underwent a xenon-computed tomography (Xe-CT) and subsequently perfusion CT to evaluate the cerebral circulation on days 1-3. We measured CBF using Xe-CT and mean transit time (MTT: the width between two inflection points [maximum upward slope and maximum downward slope from inflow to outflow of the contrast agent]) using perfusion CT and calculated the cerebral blood volume (CBV) using the AZ-7000W98 computer system. The relationships of the hemodynamic parameters CBF, MTT, and CBV to the Glasgow Coma Scale (GCS) score and the Glasgow Outcome Scale (GOS) score were examined. There were no significant differences in CBF, MTT, and CBV among GCS3-4, GCS5-6, and GCS7-8 groups. The patients with a favorable outcome (GR and MD) had significantly higher CBF and lower MTT than those with an unfavorable one (SD, VS, or D). The discriminant analysis of these parameters could predict patient outcome with a probability of 70.6%. During the early phase, CBF reduction and MTT prolongation might influence the clinical outcome of TBI. These parameters are helpful for evaluating the severity of cerebral circulatory disturbance and predicting the outcome of TBI patients.

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-e-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.

We investigated the usefulness of perioperative blood glucose control in patients undergoing coronary artery bypass grafting (CABG).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).(1) In the DM group, the amount of insulin (U) used during surgery was greater (P0.05), and the duration of ICU stay was longer (P0.05). The incidence of all complications was higher in the DM group (P0.05). (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%, P0.05). In the IH, the duration of ICU stay (P0.01) was longer, and the incidence of all complications was higher (P0.05). (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.Strict perioperative blood glucose control may help to improve the outcomes of CABG.

We describe a case of a 75-year-old man with abdominal aortic and right femoral tuberculous pseudoaneurysms 32 months after intravesical bacillus Calmette-Guerin therapy for bladder cancer. These aneurysms were probably brought on by systemic infection by Mycobacterium bovis. The infrarenal aorta and right common femoral artery were successfully replaced with an in situ expanded polytetrafluoroethylene graft. Tuberculous pseudoaneurysm after bacillus Calmette-Guerin therapy for malignancy is very rare, and we review the related literature.

To determine whether a dynamic cultured biograft can positively affect the function of the damaged heart.We ligated the coronary artery (LAD) of rats to generate a model of myocardial infarction (MI) and then implanted them with the following grafts comprising vascular smooth muscle cells (VSMCs) derived from the rat aorta and seeded onto biodegradable patches (patch replacement therapy; (PRTx)): control without PRTx, PRTx without seeded cells, PRTx with static cultured VSMCs, PRTx with dynamic cultured VSMCs and sham-operated. Cultured VSMCs were labeled with PKH26 for identification after implantation, and the centre of the MI site was excised and replaced with an implanted biograft. Cardiac performance was monitored for 12 weeks thereafter and followed by a histological study.Although the ejection fraction of the damaged heart improved in all groups that were transplanted with grafts, remodeling was prevented only in groups with a dynamic or static cultured patch. More cells were α-SMA-positive in the group with the dynamic, rather than the static cultured patch. Cells were positive for PKH26 in the biograft and in the infarcted myocardium.Dynamic cultured biografts improved the function of the infarcted myocardium more than statically cultured biografts or those without cells.

Reported herein is a patient with valvular dysfunctions due to thorombosis developed 14 years after mitral valve prosthesis with Bjork-Shiley valve, who could be rescued by emergency operation. A 44-year-old woman was admitted to the hospital because of hemorrhagic gastric ulcer. There was a history of mitral valve prosthesis with Bjork-Shiley valve for mitral insufficiency in 1976, and subsequent anti-coagulation therapy on an ambulant basis, after admission her symptoms of heart failure were aggravated. She was diagnosed as dysfunction of the artificial valve and underwent an emergency operation for reconstruction of the valve with 29 mm of St. Jude Medical valve. The findings at the operation revealed that a newly formed thrombosis at the minor-strut area had been inhibiting the motility of the valve.After the operation, her condition was improved and she was discharged at Day 20 of illness. This case was thus identified as having causative factors of nutritive infusion and administration of hemostatic agent upon suspending the anticoagulation therapy due to hemorrhagic gastric ulcer after 14 years of the term with no complaint of heart failure. It was also diagnosed as dysfunction of artificial valve decisively induced by a newly formed thrombosis which was assumed to becaused by the increased blood coagulation.

A 54-year-old man underwent left anterior descending artery bypass grafting with cell patch therapy for myocardial infarction. We applied a novel approach to replicating the infarcted myocardium by anchoring polyglycolic acid felt seeded with autologous peripheral blood mononuclear cells in front of the infarcted area. The cell patch remained fixed to the myocardium for 1 month, and the infarcted myocardium was reperfused.

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.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.Cryopreserved cells proliferated more effectively than control cells. Levels of basic fibroblast growth factor and transforming growth factor-β1 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.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.

Computed tomography in a 74-year-old man with intermittent claudication revealed an abdominal aortic aneurysm, retroperitoneal hematoma, vertebral erosion, and total aortic occlusion. Surgery was delayed for 9 months after definitive diagnosis of contained rupture of the aortic aneurysm to allow treatment for ischemic heart disease and cardiac failure. After interposing a Y-shaped woven Dacron graft, the intermittent claudication was alleviated. The postoperative course was uneventful.

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.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.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.Dynamic culture is useful for constructing tough biografts by the pre-seeding technique.

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.

We assessed potential limitations of retrograde continuous tepid blood cardioplegia (RCTBC) for myocardial remodeling, represented by hypertrophied and/or dilated myocardium in patients with severe cardiomyopathy following single aortic valve replacement.The study was conducted on 91 patients who underwent initial single aortic valve replacement with tepid cardiopulmonary bypass (CPB) and RCTBC. Based on the postoperative maximum creatine phosphokinase (max CPK)-MB level, the patients were allocated to Group H (/=100 IU/mL) with severe cardiomyopathy or Group L (100 IU/mL) to make intergroup comparisons of preoperative, intraoperative, and postoperative parameter values.Preoperative measurements were as follows: pressure gradient between left ventricle and aorta (DeltaPG), 92.8+/-46.2 mmHg in Group H and 57.9+/-41.6 mmHg in Group L (p0.01); implanted valve size, 21.0+/-2.2 mm in Group H and 22.8+/-2.2 mm in Group L (p0.01); left ventricular end-diastolic volume (LVEDV), 155.7+/-73.3 mL in Group H and 224.3+/-101.5 mL in Group L (p0.01). The rate of RCTBC flow rate increase did not differ between the groups (17.6% in Group H and 20.7% in Group L), while the rate of concomitant use of optional antegrade coronary perfusion was significantly lower in Group H (25%) than in Group L (37%) (p0.05). Pre- and post-perfusion lactic acid levels in the myocardial protection solution measured every 30 min after aortic cross clamping were higher in Group H than in Group L.The study suggests preoperative high DeltaPG, small aortic root diameter, and low LVEDV, namely, concentrically hypertrophied myocardium, as risk factors for severe cardiomyopathy after RCTBC. RCTBC in patients with any risk factor should be accompanied by an increase in initial continuous perfusion flow and/or aggressive use of intermittent antegrade coronary perfusion.

An emergency off-pump coronary artery bypass (OPCAB) was performed successfully in an aged patient with acute coronary syndrome (ACS). The patient, an 80-year-old woman residing in a nursing home, suddenly lost consciousness during lunch. The electrocardiogram (ECG) showed ventricular fibrillation (Vf) but defibrillation successfully recovered the sinus rhythm. The patient was brought to our hospital as an emergency. She underwent emergency cardiac catheterization. Coronary angiography demonstrated severe three vessel disease with left main coronary trunk (LMT) stenosis. Even during intra-aortic balloon pumping (IABP), the hemodynamic state was unstable, with repeated development of ventricular tachycardia and fibrillation. An emergency coronary artery bypass without a cardiopulmonary bypass was performed. Saving her life was of primary importance and revascularization of the left anterior descending artery (LAD) branch, was performed. Thanks to the advances made in various devices, safe and reliable anastomoses have become possible in OPCAB applied to ACS. OPCAB for ACS have become safe and reliable anastomoses following development of various devices. We think that OPCAB is an effective surgical technique for coronary revascularization for emergency or serious cases involving elderly patients.

We studied the possibility that cryopreserved human heart cells could be transplanted with some advantage.Cells derived human atrial tissues (control group (n = 13)), cryopreserved cells (cell-cryopreservation group (n = 23), and cells derived cryopreserved tissue (tissue-cryopreservation group (n = 29)) were cultured for 15 days. The cell proliferation was compared between control and cryopreservation group by growth curves. BasicFGF, TGFbeta-1, IL-6, IL-8, and cell cycle were measured at pre and post-cryopreservation. Mixed Lymphocyte-heart cell culture established by PBL and heart cells was evaluated by PBL proliferation. Transplanted cells were evaluated by visually and histology.Cryopreserved cells were proliferated much more than control cells (p0.0001). The growth factors were increased, and cytokines were decreased by cryopreservation (p0.05). The cryopreserved cell cycles were shifted to G2 + M from G1 + G0 period. Cryopreserved cells stimulated PBL less than non-cryopreserved cells (p0.0001). Transplanted cryopreserved cell were survived.Cryopreserved human heart cells can be transplanted, and proliferated much more than non-cryopreserved cells. Cryopreservation enables the human cells to be more prolific, and reduced the immunogenicity of them. The transplanted cryopreserved cells survived and formed cardiac-like tissue.

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."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.No patients died in the hospital. The tumor size correlated with the preoperative IL-6 and/or alpha1-globulin values (P0.05). 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.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."

Cultured myocyte transplantation into an infarcted myocardium has been shown to improve contractile function. Cryopreservation of cultured muscle cells or heart tissue will be important for the technology to be practical. This study, using fetal cardiomyocytes, evaluated the optimal conditions for muscle cell cryopreservation. Study 1: Fetal rat cardiomyocytes were isolated and cultured. The freshly isolated and passage 1, 2, 3 and 4 cells were cryopreserved in a solution containing 70% IMDM, 20% FBS and 10% DMSO and stored in -196 degrees C for 1, 2, 4, 8, 12 and 24 weeks. The cells were thawed and cultured. Cell number and contractility were evaluated at 0, 2, 4, 6, 8 and 10 days of culture. Study 2: Rat myocardium was cryopreserved in sizes of 0.2, 2 and 6 mm3 for 1 week. The tissue was thawed and cells were isolated. Cell growth and contractility were evaluated. (1) Cardiomyocytes grew and contracted after cryopreservation. Storage time did not affect cell survival rate, beating cell numbers and beating rates. Increasing cell passage prior to cryopreservation decreased the percentage of beating cells. (2) Cells isolated from cryopreserved tissue grew in vitro and contracted normally. Cell yield decreased with increased cryopreserved tissue size. Fetal rat cardiomyocytes survived and functioned after in vitro cryopreservation. Viable cells can be isolated from cryopreserved myocardium and cultured. Cryopreservation of small pieces of myocardium is preferred for maximal cell yields.

Cultured myocyte transplantation into an infarcted myocardium has been shown to improve contractile function. Cryopreservation of cultured muscle cells or heart tissue will be important for the technology to be practical. This study, using fetal cardiomyocytes, evaluated the optimal conditions for muscle cell cryopreservation. Study 1: Fetal rat cardiomyocytes were isolated and cultured. The freshly isolated and passage 1, 2, 3 and 4 cells were cryopreserved in a solution containing 70% IMDM, 20% FBS and 10% DMSO and stored in −196°C for 1, 2, 4, 8, 12 and 24 weeks. The cells were thawed and cultured. Cell number and contractility were evaluated at 0, 2, 4, 6, 8 and 10 days of culture. Study 2: Rat myocardium was cryopreserved in sizes of 0.2, 2 and 6 mm3 for 1 week. The tissue was thawed and cells were isolated. Cell growth and contractility were evaluated. (1) Cardiomyocytes grew and contracted after cryopreservation. Storage time did not affect cell survival rate, beating cell numbers and beating rates. Increasing cell passage prior to cryopreservation decreased the percentage of beating cells. (2) Cells isolated from cryopreserved tissue grew in vitro and contracted normally. Cell yield decreased with increased cryopreserved tissue size. Fetal rat cardiomyocytes survived and functioned after in vitro cryopreservation. Viable cells can be isolated from cryopreserved myocardium and cultured. Cryopreservation of small pieces of myocardium is preferred for maximal cell yields.

Background: The present study examined the survival and rate of contraction of (1) cardiomyocytes cultured from cryopreserved fetal rat myocardium and (2) cryopreserved cultured cardiomyocytes. In addition, the effects of transplantation of cryopreserved fetal cardiomyocytes were evaluated. Methods: Segments of fetal rat myocardial tissue (0.2, 2.0, and 6.0 mm 3 mince size) and cultured cardiomyocytes were cryopreserved in liquid nitrogen for 1, 2, and 4 weeks. After cryopreservation, the tissue samples and cultured cardiomyocytes were thawed at 37°C and cultured, and cell proliferation and rate of contraction were determined. Cultured cryopreserved (n = 5) and noncryopreserved (control, n=5) fetal cardiomyocytes were transplanted into the subcutaneous tissue and into a transmural left ventricular free wall scar of Sprague-Dawley rats (n = 3). The survival and rate of contraction of these transplanted cells were also examined. Results: Cryopreservation of cultured fetal cardiomyocytes resulted in viable and functional cardiomyocytes although the cell number and percentage of beating cells were diminished. Survival of cardiomyocytes isolated from cryopreserved fetal myocardium was a function of tissue size before cryopreservation; the lowest survival was recorded in tissues with the largest mince size (6.0 mm 3 ). The subcutaneous transplants contracted spontaneously and regularly with an idioventricular rhythm. In addition, the transplanted cardiomyocytes were elongated and formed a myocardium-like pattern with blood vessels present within the contractile tissue. In the transmural left ventricular scar, both control and experimental fetal cardiomyocyte transplants formed myocardium-like tissue. Conclusions: The present study uncovers the following key observations: (1) cryopreservation of fetal cardiomyocytes and cardiomyocytes isolated from cryopreserved myocardial tissue results in viable and functional cells, (2) cryopreserved fetal cardiomyocytes can be successfully transplanted into subcutaneous and myocardial scar tissue, and (3) improvements in cryopreservation techniques are required to augment the rates of cardiomyocyte survival observed in the study. (J Thorac Cardiovasc Surg 2001;121:98-107)

During implantation of a pacemaker into a 15-year-old male (height: 155 cm, weight: 65 kg) suffering from complete atrioventricular block, it was difficult to exteriorize the myocardium by approaching from below the xiphoid process so an operative field was obtained by using a heart stabilizer. A myocardial electrode was fixed after confirming stable circulatory dynamics with no arrhythmia and good R wave amplitude and pacing thresholds. As the heart stabilizer is now a vital device for off-pump coronary artery bypass (OPCAB), we consider that it will also become a useful device for procedures other than OPCAB in the field of cardiac surgery.