To the Editor:
We read with much interest the article by Held et al. [1] regarding pulmonary hypertension (PH) due to hypoventilation. In this retrospective study, the authors reported 18 patients with alveolar hypoventilation (due to obesity or chronic obstructive pulmonary disease (COPD)) and daytime PH associated with reduced exercise capacity. They showed that noninvasive positive-pressure ventilation (NIPPV) was followed by significant improvement in haemodynamics and exercise capacity; thus, strongly supporting the use of NIPPV in patients with hypoventilation and PH, and suggesting a major role for hypoxia and hypercapnia in PH [2].
As it is unknown whether PH-specific therapy targeting vasculopathy and remodelling of the pulmonary arteries may also have an impact in this setting, we retrospectively studied patients with chronic respiratory insufficiency and hypoventilation treated with long-term NIPPV who received off-label specific therapy for severe PH.
We extracted from the French registry, in which all consecutive adult patients with PH are prospectively included with written consent [3], incident cases from our centre …