Cardiac transplantation. Emerging from an experiment to a service.

Cardiac transplantation was resumed at the University Health Center of Pittsburgh in 1980 after a hiatus of 12 years. Prior to April 15, 1986, 270 hearts had been transplanted. Participants have been forced to reorder personal, professional, and institutional commitments to adapt to new demands of pre- and post-operative care and to develop flexibility in the operative scheduling of routine cardiac surgical cases. The actuarial survival has been 78, 69, and 64% at 1, 2, and 3 years. Much has been learned about evolving immunosuppression based on cyclosporine and of the allogenic response. An increasing proportion of recipients are mortally ill (54%), and for these urgent patients the wait for a donor organ continues to lengthen. The cardiac surgeon performing transplantations will need to grow with allied developments in xenotransplantation and mechanical cardiac support devices in order to keep pace with his evolving specialty.     

Interleukin-6, a marker of preservation injury in clinical lung transplantation.

Interleukin-6 (IL-6) is one of the cytokines produced by human alveolar macrophages, lung parenchyma, and other cells in response to injury and infection. We hypothesized that IL-6 is released from poorly preserved lung grafts and may serve as a marker of preservation injury. Sixteen patients who received lung allografts were enrolled in this study. The average ischemic time was 284 +/- 78 minutes. Serum IL-6 level was measured before and at 4 and 24 hours after reperfusion of the grafts by an enzyme-linked immunosorbent assay. Preservation injury was assessed by (1) the need for prolonged intubation (> 7 days), (2) the arterial/alveolar oxygen tension ratio (PaO2/PAO2 ratio) at 4 hours after graft reperfusion (only in heart-lung or double lung recipients), (3) the presence of diffuse alveolar damage on first lung biopsy, and (4) the 30-day graft survival rate. IL-6 level peaked at 4 hours after reperfusion and returned to baseline at 24 hours. The patients were divided into group I (n = 6) and group II (n = 10), depending on whether the 4-hour IL-6 level was more than 1000 pg/ml or less than 500 pg/ml, respectively. Group I patients required longer intubation (p < 0.01) and had a lower PaO2/PAO2 ratio (p < 0.001), more diffuse alveolar damage (p < 0.01), and a lower graft survival rate (p < 0.01) than those of group II. No bacterial, fungal, or viral infection was found during postoperative week 1 in either group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia

The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.     

Hemodynamic Parameters Influencing Clinical Performance of Novacor Left Ventricular Assist System

The interrelationships between hemodynamic variables including right ventricular (RV) performance with filling/ejection dynamics of the Novacor left ventricular assist system (LVAS) were determined in 10 of 11 patients who received LVAS as a bridge to heart transplant. Nine were successfully transplanted. Data were obtained intraoperatively, at periodic intervals up to 48 h postimplant and at explant. The hypotheses investigated included (a) RV performance influences LVAS filling characteristics and (b) LVAS pump output is influenced by systemic vascular resistance (SVR). During the period of LVAS support (2-126 days), pumping characteristics included a mean filling volume of 51 ml (range, 24-70), residual volume of 4.9 ml (range, 1-18), pump rate of 113/min (range, 63-175), and pump output of 5.81/min (range, 2.8-8.2). Multiple regression analysis identified pulmonary vascular resistance (PVR), RV stroke work index (RVSWI), and pulmonary capillary wedge pressure, but not RV ejection fraction, pulmonary artery pressure, or central venous pressure (CVP) as the most important correlates with LVAS filling volume (p less than 0.001, R2 = 0.6). In addition, LVAS pump output was influenced mainly by RVSWI, PVR, and SVR (p less than 0.001, R2 = 0.7). It was concluded that LVAS performance is highly dependent on RV function and systemic/pulmonary vascular resistances.     

Propagation of alloreactive lymphocytes from histologically negative endomyocardial biopsies from heart transplant patients. Association with subsequent histological evidence of allograft rejection

Endomyocardial biopsies from heart transplant patients were cultured in vitro in the presence of Interleukin-2 and irradiated feeder cells to propagate graft-infiltrating lymphocytes. A correlation was seen between the frequency of lymphocyte growth and the degree of cellular infiltration of the biopsies. In this study, 43 of 113 (38%) histologically negative biopsies obtained from 55 patients during the first month post-transplant yielded lymphocyte cultures. The cumulative incidence of subsequent histological rejection was considerably higher in patients with such "grower" biopsies than in patients with "nongrower" biopsies. In the grower group, we were able to obtain data on alloreactivity of 32 lymphocyte cultures assayed by primed lymphocyte testing (PLT). The presence of donor-specific PLT reactivity in the cultured lymphocytes was associated with an additional risk for subsequent histological rejection. These findings suggest that the in vitro culturing of histologically negative endomyocardial biopsies will identify patients at increased risk for developing heart transplant rejection.