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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.

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.

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.

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.

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.

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.