Effect of Nasal High Flow (NHF) on Right Heart Function in Stable Patients with Pulmonary Hypertension of Different WHO Classes.

Background

Nasal high flow (NHF) has various effects on the respiratory system in acute and chronic conditions. There are initial reports that NHF is also able to influence cardiac function in acute decompensation. This study was designed to clarify whether NHF has an influence on the right heart in stable patients with chronic pulmonary hypertension.

Methods

Forty-one stable patients from different pulmonary hypertension (PH) WHO classes were recruited. Most patients were assigned to WHO classes 1 and 3. All received a right heart catheterization and blood gas analysis. Oxygenation was kept constant. The mean pulmonary arterial pressure (mPAP), wedge pressure (PC), cardiac output (CO), diastolic pulmonary gradient (DPG), pulmonary arterial resistance (PVR) and other parameters were determined. The patients then used NHF at 35 L/min for 20 min, after which the right heart catheter measurements were repeated with ongoing NHF therapy.

Results

In the entire cohort and in the subgroups, there were no changes in right heart function or cardiac ejection fraction. The blood gases did not change either.

Conclusions

Thus, there is no effect of NHF on right heart function in stable patients with PH.