COMPUTER-ASSISTED NEUROVEGETATIVE MONITORING IN PATIENTS AFTER HEART-TRANSPLANTATION

The effects of orthotopic heart transplantation on spontaneous fluctua tions of the respiration rate and heart rate were studied with a compu ter-assisted system for neurovegetative monitoring in 22 patients (mea n age +/- SD: 48.7 +/- 9.4 years) 19.5 +/- 14.4 months after transplan tation. The control group consisted of 12 healthy volunteers (mean age +/- SD: 38.7 +/- 6.6 years). The mean (+/- SE) respiratory rate was h igher in the transplantation group than in the control group (17.7 +/- 0.8/min vs. 14.6 +/- 1.1 breaths/min, P < 0.2). The mean variability of the respiratory rate was smaller in the transplant patients than in the controls (3.7 +/- 0.3 vs. 2.8 +/- 0.4, P < 0.2). The heart rate v ariability coefficient in the patients after transplantation was lower than that in the controls (1.3 +/- 0.1 % vs. 6.9 +/- 0.5 %, P < 0.001 ). Spectral analysis of heart rate variability showed a smaller decrea se of variability of respiration (P < 0.05) than of blood pressure reg ulation (P < 0.001) or of the angiotensin-renin system (P < 0.001). A separate group of 7 transplant patients (mean age 51.0 +/- 7.7 years) had activated cardiac pacemakers and thus no spontaneous physiologic h eart rate oscillations. The variability of the respiratory rate in the se patients was lower than in the other 22 transplant patients (1.8 +/ - 0.2 vs. 3.7 +/- 0.3, P < 0.001). The data provided by multiparametri c neurovegetative monitoring support the evaluation of complex regulat ory mechanisms of respiratory and cardiovascular function and their ad aptability after orthotopic heart transplantation.