Over the last fifteen years, the therapy of pulmonary hypertension has been enriched with several drugs, especially for the progress made in the forms of pulmonary arterial hypertension. In forms of pulmonary hypertension secondary to other pathologies one attempts to solve the basic disease without using specific medications; Instead, in the forms of pulmonary arterial hypertension, a conventional therapy (diuretics, anticoagulants, digoxin, calcium, oxygen) and a specific therapy that acts on an altered functioning of the cells that constitute the Wall of the pulmonary vessel (endothelial cells).
Currently, specific drugs belong to three different classes: Prostanoids, endothelin receptor antagonists, phosphodiesterase-5 inhibitors.
The Prostanoids (Epoprostenol, Treprostinil, Iloprost) are substances with a vasodilator, antiproliferative and Antiplatelet action, similar to the prostacyclin that is physiologically produced by the cells lining the inner wall of the vessel. Currently they are the most effective medications available and are used in the most severe cases. Their administration is through complex infusion devices that use different pathways and modalities (epoprostenol continuous intravenous, treprostinil subcutaneously continuous, inhaled iloprost).
Endothelin receptor antagonists (Bosentan, Ambrisentan) are drugs that tend to block the deleterious effects of endothelin, a substance normally produced in our organism and which, by interacting with two et-A and ET-B receptors, performs An important vasoconstrictor action and stimulating cell replication. In patients with pulmonary hypertension, an increase in their blood circulation has been documented. The Bosentan acts by blocking both the ET-A and ET-B receptors, the Ambrisentan is selective only for the ET-a receptors. Both drugs are clinically and hemodynamically effective; Their administration takes place orally. Patients treated with endothelin receptor antagonists should undergo periodic controls of liver function for the possibility of adverse effects.
Phosphodiesterase-5 inhibitors (Sildenafil, Tadalafil) are drugs that increase the effects of nitric oxide (NO), a substance normally present in our body that carries out a potent vasodilator and antiproliferative effect. Both drugs are clinically and hemodynamically effective; Their administration takes place orally; For sildenafil, intravenous administration was also recently approved.
Guanylate-Soluble Cycling stimulators Act by activating the soluble cycling enzyme guanylate (SGC), responsible for the production of cyclic GMP, a small molecule that causes vasodilation and reduces the proliferation of muscle cells In the wall of the vase.
The current therapeutic approach is to initiate specific therapy with an oral medication (Bosentan, Ambrisentan, Sildenafil and Tadalafil) when the patient is in stable clinical and hemodynamic conditions and initiate a combination therapy between drugs Oral or add prostanoids when the initial therapy has not given the desired results or when there is an important clinical and hemodynamic impairment from the outset.
The emerging problem is that many "centers" are able to start oral therapy but only a few "expert centres" know how to manage the most complex therapies (prostanoids) with the risk for patients not to have access to all available therapies. It is therefore important to raise awareness of doctors in order to allow patients to be sent to expert centres that can ensure a timely diagnosis and, above all, appropriate treatment.
You will find below the link to download the updated explanation to 2012 of existing therapies on the manual "Living with Pulmonary hypertension", in the chapter "treatment of pulmonary hypertension".