Sano, Shunji

Our meticulous investigation of ePTFE graft breakage when a wire placed at the edge of an ePTFE graft was pulled, revealed that, depending on the breakage pattern, a break starts much earlier than the peak suture retention strength, which is the current international indicator for anastomotic-site break strength. Furthermore, the breakage patterns differ based on the thickness of the wire and the fiber direction of the ePTFE graft. Based on these findings, we advocate measuring the peak suture retention strength using 0.10-mm sutures and a standardized wire thickness in order to assess the anastomotic retention strength of ePTFE grafts.

A shortage of donor organs in clinical transplantation prompted us to study whether resuscitated dead hearts could be utilized for successful orthotopic heart transplantation. After 60 min of hypoxic cardiac arrest, one group of canine hearts was resuscitated (Res group, n = 6). The other group was harvested directly (Non-Res group, n = 6). In the Res group, cardiopulmonary bypass was utilized for resuscitation at 37 degrees C and the animals were then core-cooled to 15 degrees C. The hearts then were preserved in University of Wisconsin solution and orthotopically transplanted. Stable prostacyclin analogue (OP2507) and verapamil, a calcium antagonist, were added to the cardioplegia, and substrate-enriched warm blood cardioplegia and a hydroxy radical scavenger (EPC) were administered at the time of reperfusion of the transplanted heart. All animals in each group were successfully weaned from cardiopulmonary bypass with dopamine (5 micrograms/kg/min). Cardiac function without dopamine was better preserved in the Res group than the Non-Res group (Emax: 130.6 +/- 41.5% vs. 47.1 +/- 24.7%; mean +/- SD, as percent of postbrain death values, P < 0.01 by unpaired t-test). Cadaver hearts 60 min after anoxic arrest can be successfully re-animated and orthotopically engrafted. In addition, the core-cooling technique is useful. We believe this study serves as the key step in the clinical application of dead hearts to successful cardiac transplantation.

We investigated the usefulness of helical computed tomography(CT)in the morphological diagnosis of pulmonary vein stenosis, particularly that in infants and small children. In total, 20 helical CT examinations were performed in 10 post-operative cases of Total Anomalous Pulmonary Venous Drainage(TAPVD), 3 cases of single right ventricle, and 1 case of single left ventricle. In all cases, distinct morphological imaging was possible. Pulmonary vein stenosis could be categorized into three types: (1)stenosis from the anastomosis of the common pulmonary vein (CPV)-the left atrium (LA) to the peripheral pulmonary vein; (2) stenosis only at the anastomosis of CPV-LA; and (3) stenosis due to compression by nearby organs. Coronal views by multiplanar reconstruction (MPR) provided morphological information along the up-down direction of the body axis. Morphological diagnosis of pulmonary vein stenosis is important in deciding prognosis and therapeutic regimens, and helical CT was considered useful for such diagnosis in our 14 young patients.