Cardiopulmonary transplantation for congenital heart disease in the adult.

BACKGROUND: Patients surviving into adulthood with congenital heart disease (CHD) often succumb to progressive cardiopulmonary dysfunction. For these patients transplantation is often considered. METHODS: We performed a retrospective review of 69 adults (age >18 years) with CHD transplanted between 1984 and 1999. RESULTS: We evaluated 31 heart-lung (HLTxp), 30 lung (LTxp), and 8 heart (HTxp) transplants performed in 22 men and 47 women with CHD. Mean age was 37 +/- 10 years with a mean follow-up of 3.1 +/- 3.5 years. A concomitant cardiovascular procedure was performed in 1 HLTxp, 23 LTxp, and 2 HTxp. Early mortality (>30 days) was 26% (8/31) for HLTxp, mostly due to bleeding. Early LTxp mortality was 23% (7/30), largely due to graft failure. One and 3-year survival was similar in adults transplanted for CHD and adults transplanted for other disease. Early mortality among HTxp recipients was 50% (4/8) from rejection or technical complications. Survival for patients undergoing HLTxp versus LTxp with cardiac repair was similar. When examined by era, the survival of patients transplanted for CHD between 1992 and 1999 was greater than that of patients transplanted between 1984 and 1991. CONCLUSIONS: Adults undergoing HLTxp and LTxp for CHD can expect survival comparable to that of non-CHD adults. In the presence of a reparable cardiac lesion, LTxp with cardiovascular repair for CHD is an attractive option, optimizing organ allocation. Specific technical concerns are discussed. Survival of adults undergoing cardiopulmonary transplantation for CHD has improved over time.

Monocyte tissue factor expression and ongoing complement generation in ventricular assist device patients.

BACKGROUND: Ongoing complement activation in patients with a ventricular assist device may contribute to observed hemostatic abnormalities and cellular aggregation by mediating leukocyte and platelet activation, formation of leukocyte-platelet conjugates, and the tissue factor pathway of coagulation. METHODS: Blood from 30 patients was collected before ventricular assist device implantation and during the implantation period. Plasma levels of thrombin-antithrombin III complexes, C3a, and SC5b-9 were measured by commercial enzyme-linked immunosorbent assay. Flow cytometry was used to measure circulating monocyte tissue factor expression and circulating monocyteplatelet and granulocyte-platelet conjugates. RESULTS: Thrombin-antithrombin III complex level and monocyte tissue factor expression peaked in the early postoperative period, with maxima occurring on postoperative days 5 and 3, respectively. Levels of C3a and SC5b-9 remained dramatically elevated over normal values for the duration of the study (6 and 5 times upper normal, respectively). Levels of monocyte-platelet conjugates were normal before implantation, decreased during the first 4 postoperative days, and then increased and remained elevated. Levels of granulocyte-platelet conjugates were elevated over the normal range before implantation and remained elevated from postoperative days 3 to 21. A positive correlation was found between levels of SC5b-9 and granulocyte-platelet conjugates (Spearman R=0.66; p < 0.001), and between levels of C3a and thrombin-antithrombin III complex (Spearman R=0.13; p=0.021). CONCLUSIONS: The data suggest a model in which complement mediates formation of leukocyte-platelet aggregates and may indirectly contribute to thrombin generation through monocyte tissue factor expression.

Comparative in vitro analysis of topical hemostatic agents.

Hemostatic agents are broadly utilized across the surgical specialties. While specific characteristics desirable for individual applications may vary, these agents generally are expected to aid the patient's coagulation system in the rapid development of an occlusive clot. Six commonly utilized hemostatic agents were quantitatively compared in terms of their ability to mediate platelet aggregation, deposition and activation, and initiate gross clot formation in a series of in vitro tests. Three types of collagen sponges (Actifoam, Helistat, Instat), microfibrillar collagen (Avitene), a gelatin sponge (Gelfoam), and oxidized regenerated cellulose (Surgicel) were studied. Platelet aggregation: Citrated platelet rich plasma (PRP) was contacted with hemostatic agents both with and without thrombin in a stirred cuvette and the platelet count was measured over 5 min. Platelet deposition: To approximate arterial wounds, PRP was perfused in a controlled manner through hemostatic agents, and the effluent platelet count was measured over time. Platelet activation: ATP secretion from PRP contacted with hemostatic agents in a stirred cuvette was measured at 1 and 5 min. Clot formation: The clotting time of nonanticoagulated whole blood contacted with the hemostatic agents was measured. Materials which depleted platelets most rapidly and effectively in the perfusion system (Avitene, Helistat, and Actifoam) were also the most effective inducers of platelet aggregation and secretion. Clot formation (likely to be platelet dependent) was also more rapid in this group. An overall activity ranking combined the relative performance of each hemostatic agent on the various tests: Actifoam approximately Avitene > Helistat >> Gelfoam > Instat > Surgicel. The activity ranking generally reflects the materials used in these agents (collagen > gelatin > oxidized regenerated cellulose), as well as their processing (chemical crosslinking in collagen sponges may lower activity). Such in vitro assessment of the relative platelet and coagulation activities of hemostatic agents might serve as a useful screening tool before investigating properties which require more expensive animal or clinical testing.