No abstract

Background-The application of iloprost, a stable prostacyclin analogue, by inhalation has been shown to improve hemodynamic variables in patients with primary pulmonary hypertension. However, repetitive inhalations are required due to its short-term effects. One potential approach to prolong and increase the vasorelaxant effects of aerosolized iloprost might be to combine use with phosphodiesterase inhibitors. Methods and Results-The short-term effects of 8.4 to 10.5 g of aerosolized iloprost, the phosphodiesterase type 5 inhibitor sildenafil, and the combination thereof were compared in 5 patients with primary pulmonary hypertension. Aerosolized iloprost resulted in a more pronounced decrease in mean pulmonary arterial pressure (PAP) than sildenafil alone (9.4Ϯ1.3 versus 6.4Ϯ1.1 mm Hg; PϽ0.05). The reduction in mean PAP after sildenafil was maximal after the first dose (25 mg). The combination of sildenafil plus iloprost lowered mean PAP significantly more than iloprost alone (13.8Ϯ1.4 versus 9.4Ϯ1.3 mm Hg; PϽ0.009). No significant changes in heart rate or systemic arterial pressure were observed during any treatment. The treatments were well tolerated, without major adverse effects. Conclusions-Sildenafil caused a long-lasting reduction in mean PAP and pulmonary vascular resistance, with a further additional improvement after iloprost inhalation. These data suggest that small doses of a phosphodiesterase type 5 inhibitor may be a useful adjunct to inhaled iloprost in the management of pulmonary hypertension.

No abstract

Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r = −0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation.

No abstract