TREATMENT : SUPPORTIVE TREATMENTS

Diuretic Therapy

Diuretics are indicated to manage volume overload due to right ventricular failure. In some cases, intravenous diuretics are required.

Oxygen Supplementation

Hypoxia is a potent pulmonary vasoconstrictor, leading to increased pulmonary arterial pressure both acutely and chronically. Oxygen supplementation is recommended by most experts to maintain arterial oxygen saturations above 90%, both at rest and with exercise.

Cardiac Glycosides

The role of cardiac glycosides in PAH is unclear. Digoxin is occasionally prescribed in patients with right ventricular failure or low cardiac output, although there is little data to support this intervention.

Anticoagulation

Although there have been no prospective, randomised, placebo controlled trials, evidence from several studies suggests that that the use of long term anticoagulation in patients with PAH improves survival. In the absence of contraindications, anticoagulation should be a standard component of the treatment regimen in patients with PAH. The target INR is 2.5 with warfarin therapy.

Calcium channel blockers (CCB)

The appropriate use of CCBs in patients with pulmonary arterial hypertension is controversial. Concern exists that CCB therapy in non-responders may further impair cardiac function. Treatment of PAH with CCBs is reserved for patients who demonstrate evidence of acute vasoreactivity, currently defined as a reduction in mean pulmonary artery pressure = 10mmHg to a level that is = 40mmHg, with increased or unchanged cardiac output during testing with an acute, short acting vasodilator e.g. inhaled nitric oxide. Only those patients with significant haemodynamic reversal of pulmonary hypertension during acute vasodilator testing should be considered candidates for chronic CCB treatment. About 13% of IPAH patients exhibit acute vasoreactivity, and of this group, only half experience sustained benefit from chronic CCB treatment.