Diagnostic and Prognostic Impact of Diastolic Pulmonary Arterial Pressure (DPAP) and DPAP-Derived Calculations at Rest and during Vasoreactivity Testing in Children with Pulmonary Arterial Hypertension

Objectives: Diastolic pulmonary arterial pressure (dPAP) is regarded to be less sensitive to flow metrics as compared with mean PAP (mPAP) and was therefore proposed for the assessment of a precapillary component in patients with postcapillary pulmonary hypertension. To analyze the diagnostic and prognostic impacts of dPAP in patients with pure precapillary PH, we purposed to compare the correlation between dPAP and mPAP, as well as hemodynamically derived calculations (ratio of PAP to systemic arterial pressure [PAP/SAP], pulmonary vascular resistance index [PVRI], and transpulmonary gradient [TPG]), using both dPAP and mPAP, at rest and during acute vasoreactivity testing (AVT) in children with idiopathic/heritable pulmonary arterial hypertension (IPAH/HPAH). Furthermore, we aimed to assess the association of these metrics (at baseline and changes after AVT) with transplant-free survival.

Methods: We conducted a retrospective analysis of the global TOPP (tracking outcomes and practice in pediatric pulmonary hypertension) registry including 246 IPAH/HPAH patients. Of these, 45 children (18.3%) died, and 13 (5.3%) received lung transplantation during the observation period.

Result: The dPAP and mPAP-derived variables showed almost linear relationship. Higher mPAP/mSAP and dPAP-/mPAP-derived PVRI at rest were associated with time to death/transplantation. At maximum AVT-response, the decrease of dPAP and mPAP, DPG, and TPG, as well as dPAP/dSAP and mPAP/mSAP, was associated with time to death/transplantation, showing higher significance than corresponding baseline values. Remarkably, no predictive value was found for PVRI-reduction during AVT, neither dPAP nor mPAP derived.

Conclusion: There is a strong relationship between dPAP and mPAP-derived variables. According to our results, hemodynamics during AVT (irrespectively of dPAP or mPAP derived) may have more prognostic implications than resting hemodynamics in children with IPAH/HPAH, except for PVRI.

Publication History

Article published online:
21 February 2021