Occlusive Venopathy Phenotype in Hereditary Pulmonary Arterial Hypertension

A 33-year-old male with severe hereditary pulmonary arterial hypertension had a confirmed diagnosis of occlusive venopathy and microvasculopathy. He remained stable for three and a half years on oral sildenafil, 75 mg t.i.d. (six-minute walked distance of 375 m vs 105 m at baseline), but required addition of bosentan (125 mg b.i.d.), subsequently. Despite the fatal outcome at five years post-diagnosis, the observations suggest a potential usefulness of vasodilators as a bridge for lung transplant in selected cases with significant venous/capillary involvement. The occurrence of veno-occlusive and capillary lesions in the familial form of pulmonary arterial hypertension reinforces the difficulties with the current classification of the disease.