Primary pulmonary hypertension: Do we consider the right risk factors?

Purpose- To evaluate the importance of different risk factors in patients with primary pulmonary hypertension. Methods- In a retrospective study we reviewed the data concerning the commonly known risk factors for the development of this disease. Results- While the risk factors generally considered were poorly frequent in our patient (pts): use of anticontraptectives 2 pts (11%), use of anorexic drugs 2 pts (11%), presence of serum antinucleus antibody 3 pts (18%), pregnancy 1 pt (5%), we found a high prevalence of HCV infection and of hystory of essential systemic hypertension. A family hystory of systemic hypertension was present in 9 pts (45%), and in 6 pts (66%) both PPH and systemic hypertension were found to be concomitant at the time of examination. Anti-HCV antibody were present in 6 pts (30%), and in only one of them there was evidence of both portal the hypertension and cirrhosis. Conclusions- The high prevalence of systemic hypertension in pts with PPH may imply a common pathogenic mechanism played by a wounded endotelium unable to produce potent vasoactive substances like NO and prostacyclin, not only in the lung but also systemically, becoming an important element in the development of PPH and systemic hypertension in PPH may indicate a genetically determined vascular hypereactivity to common vasoconstrictive stimuli. Clinical Implications- We have also found a high prevalence of HCV infection in pts with PPH. Hepatitis C virus may therefore be a cause of the anatomic vascular changes found in PPH as has already been proven for ather Lenti Virus such as Visna Maedi virus and suggested for HIV virus infection.