**8. Treatment**

Despite advances in various treatments, there is no cure for pulmonary hypertension. The goals of treatment for pulmonary hypertension are to treat the underlying cause, to reduce symptoms and improve quality of life, to slow the growth of the smooth muscle cells and the development of blood clots; and to increase the supply of blood and oxygen to the heart, while reducing its workload.

An algorithm for treatment is shown in Figure 2. [37]

#### Pulmonary Arterial Hypertension: An Overview http://dx.doi.org/10.5772/56055 9

#### Adapted with permission from ELSEVIER (ref 33)

Barst RJ, Gibbs JS, Ghofrani HA, Hoeper MM, McLaughlin VV, Rubin LJ, Sitbon O, Tapson VF, Galiè N. Updated evi‐ dence-based treatment algorithm in pulmonary arterial hypertension. J Am Coll Cardiol. 2009 Jun 30;54(1 Suppl):S78-84.

**Figure 2. Evidence-Based Treatment Algorithm.** (Drugs within the same grade of evidence are listed in alphabetical order and not order of preference). APAH = associated pulmonary arterial hypertension; ERA = endothelin receptor antagonist; HPAH = heritable pulmonary arterial hypertension; IPAH = idiopathic pulmonary arterial hypertension; IV = intravenous; PAH = pulmonary arterial hypertension; PDE-5 = phosphodiesterase type 5; SC = subcutaneous; WHO = World Health Organization.

#### **8.1. Medical treatment**

**7.6. Exercise testing**

8 Pulmonary Hypertension

**•** Anti-HIV

**8. Treatment**

reducing its workload.

Additional Workup: includes:

several causes of an impaired ability to walk.[10]

setting of chronic thromboembolic disease

This is very helpful to assess the efficacy of therapy. Severe exercise-induced hypoxemia should cause consideration of a right-to-left shunt. Cardiopulmonary exercise assessment with a widely available 6-minute walk test is commonly used to assess and track functional capacity. [1],[10], [24],[35],[36] However, it lacks specificity in that it cannot be used to discern between

**•** Pulmonary function testing with diffusing capacity (DLCO): Elevated pulmonary artery pressure causes restrictive physiology. In patients with PAH, the diffusing lung capacity for carbon monoxide (DLCO) is reduced to approximately 60% to 80% of that predicted.

**•** Overnight oximetry or polysomnography is useful in detecting obstructive sleep apnea

perfusion pattern or diffuse, patchy perfusion abnormalities

**•** Rheumatologic serologies to look for auto-immune diseases.

of coagulation are found in some patients with PAH.

An algorithm for treatment is shown in Figure 2. [37]

that thyroid function tests be monitored serially in all patients.

**•** Ventilation/perfusion (VQ) scanning Patients with PAH may reveal a relatively normal

**•** Pulmonary angiography performed to further evaluate or better define the anatomy in the

**•** Thyroid function testing: There is an increased incidence of thyroid disease in patients with PAH, which can mimic the symptoms of right ventricular failure. Consequently, it is advised

**•** B-Type Natriuretic Peptide (BNP): Brain natriuretic peptide (BNP) levels are elevated in patients with pulmonary hypertension and correlate with the pulmonary artery pressure.

**•** If chronic arterial oxygen desaturation exists, polycythemia should be present. Hyper‐ coagulable states, abnormal platelet function, defects in fibrinolysis, and other abnormalities

Despite advances in various treatments, there is no cure for pulmonary hypertension. The goals of treatment for pulmonary hypertension are to treat the underlying cause, to reduce symptoms and improve quality of life, to slow the growth of the smooth muscle cells and the development of blood clots; and to increase the supply of blood and oxygen to the heart, while

#### *8.1.1. General measures*


travelers with PH, who will be traveling on long flights or those with a history of oxygen use, should be considered for supplemental in-flight oxygen.[32]. A flight simulation test before the flight can help determine oxygen needs at altitude.[24],[35]

pulmonary vascular pressure or symptomatic systemic hypotension and no change or a reduction of cardiac index (by more than 10 %), possibly accompanied by an increase in right atrial pressure (by more than 20 – 25 %). However, the absence of an acute response to intravenous or inhaled vasodilators does not preclude the use of intravenous vasodilator therapy. In fact, continuous intravenous vasodilator therapy is strongly suggested for these

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http://dx.doi.org/10.5772/56055

11

These drugs are thought to act on the vascular smooth muscle to dilate the pulmonary resistance vessels and lower the pulmonary artery pressure. The use of CCBs should be limited to patients without overt evidence of right-sided heart failure. In patients with IPAH (or any other form of PAH), a cardiac index of less than 2 L/min/m2 or a right atrial pressure above 15 mm Hg is a contraindication to CCB therapy, as these agents may worsen right ventricular

These drugs in general work by dilating the pulmonary arteries and, therefore, by reducing the pressure in these blood vessels and some help prevent the excessive overgrowth of tissue in the blood vessels (that decrease remodeling of the vessels). Common side effects include cough, flushing, and headache. Inhaled therapies may be useful as an adjunct to oral therapy.

Prostacyclin dilates systemic and pulmonary arterial vascular beds. These short acting drugs include epoprostenol [41] (Flolan), treprostinil (Remodulin), iloprost [42] (Ventavis), Trepros‐ tinil (Tyvaso). Parenteral vasodilators are used for patients whose IPAH fails to respond to calcium channel blockers or who cannot tolerate these agents and who have New York Heart

Long-term treatment with intravenous PGI2 improves exercise capacity, hemodynamics, and survival in most patients with PPH in NYHA functional class III or IV. Despite these favorable outcomes, continuous intravenous infusion of PGI2 is not ideal due to its cost and side effects such as flushing, headache, jaw pain, diarrhea and incidence of catheter-related infections. Survival of patients with PPH treated with epoprostenol depends on the severity at baseline, as well as the three-month response to therapy. Lung transplantation should be considered in a subset of patients who remain in NYHA functional class III or IV or in those who cannot achieve a significant hemodynamic improvement after three months of epoprostenol therapy,

There are three major classes of drugs used to treat pulmonary arterial hypertension:

patients because CCBs are contraindicated. [40]

failure in such cases.

**10.2. Prostacyclins**

or both. [40]

**10.1. Specific vasodilator therapy**

**10. Calcium Channel Blocker therapy (CCB)**

Association (NYHA) type III or IV right-sided heart failure.

