Selecting a Treatment Regimen Conventional Treatment
ÎConventional treatment or general care given to most patients with PAH includes:
> Diuretics - effective in relieving dyspnea and peripheral edema, and may reduce right ventricular volume overload in the presence of tricuspid regurgitation
> Anticoagulant therapy with warfarin is most commonly used in IPAH. There is not much data for other types of PAH.
> Oxygen supplementation Medical Treatment
ÎWhen selecting medical therapy for PAH, a variety of factors in addition to functional class—which may vary among patients and practitioners—should be considered:
> Cardiopulmonary hemodynamics > 6MWD > Signs and symptoms of right heart failure > Drug side effects profile and interactions
ÎPatients with IPAH who respond to acute vasodilator testing will sometimes benefit from calcium channel blocker therapy.
> Response defined as: a fall in mPAP ≥ 10 mm Hg to a level ≤ 40 mm Hg, with an unchanged or increased cardiac output when challenged with inhaled nitric oxide, intravenous (IV) epoprostenol, or IV adenosine.
> True responders are rare among patients with IPAH, and even more rare in other (non-IPAH) forms of the disease.
ÎThe protocols for treating patients with PAH by WHO functional class (FC) are outlined in the algorithm (Figure 1).
ÎTherapies approved for FC II patients are ambrisentan, bosentan, sildenafil, tadalafil and subcutaneous or IV treprostinil.
ÎAmong the oral therapies for FC III PAH, any of the four therapies— ambrisentan, bosentan, sildenafil or tadalafil is considered a drug of choice for early disease.
ÎAmong the IV therapies for FC IV PAH, epoprostenol is considered the drug of choice for the most critically ill patients.