Search

A 5-year-old girl has a history of epicardial VVI-pacemaker implantation due to congenital heart block at the age of 2 months. Five years later, she developed heart failure at the same time of battery depletion. The chest X-ray indicated the loop formation of the epicardial leads and the echocardiogram demonstrated paradoxical movement of ventricles. The 3-dimensional computed tomography finally revealed strangulation of biventricular apex caused by loop of the leads. She underwent reoperation. Cardiac strangulation was relieved by total removal of the loop and repositioning of right atrial and ventricular electrodes in a gentle curve of the leads. She was discharged and doing well. Cardiac strangulation is a rare, but it can be lethal. Therefore epicardial pacemaker leads should not be positioned around the ventricle with excessive redundancy.

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.

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.