PULMONARY DIFFUSION IMPAIRMENT FOLLOWING HEART-TRANSPLANTATION - A PROSPECTIVE-STUDY

The aim of this prospective study was to confirm whether and when a fa ll in gas transfer occurs following heart transplantation (HF); and to examine the potential relationship between gas transfer and haemodyna mic change, immuno-suppression, and cytomegalovirus (CMV) infection. T he lung physiology of 34 heart transplant recipients (HTR) and 14 cont rol patients undergoing coronary artery bypass grafting (CABG) were st udied. The absolute and standardized residual values of forced expirat ory volume in one second (FEV(1)), forced vital capacity (FVC), residu al volume (RV), forced residual volume (FRC), total lung capacity (TLC ), transfer factor of the lungs for carbon monoxide (TL,CO) and carbon monoxide transfer coefficient (KCO) were measured before and at 30, 6 0, 90, 120 and 150 days after HT. These data were compared to haemodyn amic status, graft rejection, cyclosporin levels and episodes of CMV i nfection. Lung function was studied in a group of patients before and 4 weeks after CABG. There was a significant fall in mean KCO after HT (pre-HT=1.29 and post-HT= 1.06 mmol . min(-1). kPa . L(-1)) but not af ter CABG (pre-CABG=1.49, post-CABG=1.5 mmol . min(-1). kPa . L(-1). No relationship was observed between gas transfer and CMV. At the latest stage following HT (150 days) there was a positive correlation betwee n TL,CO (absolute value and standardized residual) and mean cyclospori n level (r=0.48 and r=0.44, respectively) and also between the absolut e KCO and actual (r=0.56) and mean (r=0.55) cyclosporin levels. Follow ing HT, there is an early fall in gas transfer, which is independent o f the effects of surgery and bypass, implicating early immunosuppressi on (e.g. antithymocyte globulin/cyclosporin).