Pulmonale Hypertonie bei Patienten mit chronischer Nierenerkrankung mit und ohne Dialyse: Ergebnisse der PEPPER-Studie

Aims: Pulmonary hypertension (PH) is common in patients with dialysis-dependent chronic kidney disease and is an independent predictor of mortality. However, specific hemodynamics of the pulmonary circulation, changes induced by hemodialysis and prevalence of precapillary PH or pulmonary arterial hypertension (PAH) have not been evaluated in patients with chronic kidney disease.

Methods: We assessed consecutive patients with chronic kidney disease on hemodialysis (group 1, n=31) or without dialysis (group 2, n=31) in World Health Organization functional class ≥II with dyspnoe unexplained by other causes using right heart catheterization (RHC). In group 1 RHC was performed before and after dialysis. PAH was diagnosed if mean pulmonary arterial pressure (mPAP) was ≥25mmHg and pulmonary capillary wedge pressure (PCWP) ≤15mmHg (after dialysis in group 1) and if other causes of PH were excluded.

Results: In chronic kidney disease patients after dialysis, prevalence of postcapillary PH was 65% (20/31). Precapillary PH was detected in 13% (4/31). After dialysis, there were significant decreases in mPAP (from 62±18 to 55±17mmHg) and PCWP (from 25±8 to 20±6mmHg); all four cases of precapillary PH were unmasked by dialysis. In group 2, postcapillary PH was diagnosed in 22 cases (71%); no cases of precapillary PH were detected.

Conclusions: The finding that the prevalence of precapillary PH was 13% in chronic kidney disease patients on hemodialysis suggests careful screening for P(A)H in this selected patient population. The possibility that dialysis might be a trigger for the development of precapillary PH is plausible given that there were no instances of precapillary PH in the nondialysis chronic kidney disease patient group. It remains to discuss to what extent precapillary PH in CKD patients resembles PAH.