Resting hemodynamics after total versus standard orthotopic heart transplantation in patients with high preoperative pulmonary vascular resistance.

OBJECTIVE

Pretransplant pulmonary vascular resistance > or = 4 Wood-units predisposes to right ventricular failure after heart transplantation. Total orthotopic heart transplantation with bicaval and pulmonary venous anastomoses offers synchronous contractions of the atria and a normal ventricular filling pattern, but requires longer ischemic time than standard orthotopic heart transplantation. To test if total orthotopic heart transplantation improves resting hemodynamics in pts with high preoperative pulmonary vascular resistance, we analyzed 65 pts with standard and 65 with total orthotopic heart transplantation transplanted between 12/88 and 7/94. Of these, 18 with total and 15 with standard orthotopic heart transplantation had a preoperative pulmonary vascular resistance > or = 4 Wood-units.

METHODS

Right heart catheterization data were obtained at each endomyocardial biopsy. All data from biopsies at both 2 weeks and 1 year posttransplant that were free from humoral or greater than 1A cellular rejection (9 versus 13 pts) were included in a two way ANOVA. Pts with postop pacemakers, atrial fib or beta-blocker therapy at the time of biopsy were excluded.

RESULTS

Ischemic time was different (172 +/- 44 versus 142 +/- 28 min, P = 0.03). Demographics, NYHA class, pre-TX hemodynamics, donor age and inotropes were similar. Cardiac output and index were higher in the total orthotopic group at 2 weeks (6.5 +/- 1.7 versus 5.1 +/- 1.0 l/min; 3.4 +/- 0.9 versus 2.8 +/- 0.6 l/min per m2) and 1 year (7.1 +/- 2.0 versus 4.9 +/- 1.1 l/min, P = 0.002; 3.6 +/- 1.1 versus 2.6 +/- 0.5 l/min per m2, P = 0.009). Right atrial and pulmonary arterial mean pressure (mmHg) were lower with total orthotopic heart transplantation at 2 weeks (6 +/- 4 versus 9 +/- 5, P = 0.04; 22 +/- 3 versus 25 +/- 7, P = 0.1) and 1 year (5 +/- 2 versus 7 +/- 3, P = 0.02; 19 +/- 4 versus 25 +/- 7, P = 0.03). Pulmonary capillary wedge pressure (mmHg) was borderline nonsignificant (11 +/- 4 versus 13 +/- 7 at 2 weeks, 8 +/- 3 versus 14 +/- 5 at 1 year, P = 0.055), as well as pulmonary vascular resistance (1.9 +/- 1 versus 2.5 +/- 1 at 2 weeks, 1.5 +/- 0.6 versus 2.7 +/- 1.7 WU at 1 year, P = 0.051).

CONCLUSIONS

Total orthotopic heart transplantation improves cardiac output and index in pts with high preoperative pulmonary vacular resistance. There is a lower mean RA and PA pressure perhaps due to less tricuspid and mitral regurgitation. In view of the frequently observed restrictive filling pattern after cardiac transplantation, total orthotopic heart transplantation can be beneficial until this pattern has subsided by preserving atrioventricular synchrony and offering better atrial transport.