TRANSPLANT CANDIDATES CLINICAL STATUS RATHER THAN RIGHT-VENTRICULAR FUNCTION DEFINES NEED FOR UNIVENTRICULAR VERSUS BIVENTRICULAR SUPPORT

We have studied our experience since 1988 with 31 patients who require d a mechanical circulatory bridge to transplantation and also had bive ntricular failure (mean right ventricular ejection fraction 11.8%) to better define the need for biventricular or total artificial heart sup port versus univentricular support, Clinical factors including preoper ative inotropic need, fever without detectable infection, diffuse radi ographic pulmonary edema, postoperative blood transfusion, and right v entricular wall thickness were compared with hemodynamic parameters in cluding cardiac index, right ventricular ejection fraction, central ve nous pressure, mean pulmonary arterial pressure, and total pulmonary r esistance for ability to predict need for mechanical or high-dose inot ropic support for the right ventricle, Patients were grouped according to need for right ventricular support after left ventricular-assist d evice implantation: none (group A, 14) inotropic drugs (group B-1, 7), and right ventricle mechanical support (group B-2, 10), There were no differences in preimplantation hemodynamic variables. Groups B-1, and B-2 had significantly lower mixed venous oxygen saturation (39.2% vs 52.5% in group A; p < 0.001), greater level of inotropic need (p < 0.0 2), greater impairment of mental status, and lower ratio of right vent ricular ejection fraction to inotropic need (0.37 vs 0.56 for group A; p < 0.02) before left ventricular-assist device implantation, A signi ficant discriminator between groups B-1 and B-2 was the presence of a fever without infection within 10 days of left ventricular-assist devi ce implantation (43% in group B-1 vs 70% in group B-2), Group B, had m ore patients with preimplantation pulmonary edema seen on chest radiog raphy and a greater requirement for postoperative blood transfusion (5 units of cells in group B, vs 14.8 units in group B-2, Right ventricu lar wall thickness at left ventricular-assist device explantation was 0.83 cm in group B-2 vs 0.44 cm in group B-1 (p < 0.05), Transplantati on rates after bridging were 100% in group A, 71% in group B-1, and 40 % in group B-2, Clinical factors that reflect preimplantation degree o f illness and perioperative factors that result in impairment of pulmo nary blood how or reduced perfusion of the right ventricle after left ventricular-assist device implantation are now considered to be more p redictive of the need for additional right ventricular support than pr eimplantation measures of right ventricular function or hemodynamic va riables.