Pulmonary hypertension

 

Pulmonary hypertension - Chronic
Rahul Soman, M. Pharm

 

 

Definition  

Pulmonary hypertension is a hemodynamic abnormality that is defined as a mean pulmonary artery pressure of at least 25 mmHg at rest or at least 30 mmHg with exercise . It is a complex disease that can be idiopathic, familial, or associated with a wide range of disease processes.

 

Ongoing Assessment  

 

Screening Criteria  

 

For relatives of patients with familial pulmonary arterial hypertension  

* Molecular genetic test: Genetic testing and professional genetic counseling should be offered to relatives of patients with familial pulmonary arterial hypertension (FPAH) .

 

Reassessment  

 

To provide benchmarks for disease severity, response to therapy, and progression  

* Exercise tolerance test: Assessment of exercise capacity is an essential component of the evaluation process of patients with known pulmonary hypertension .

 

Medical History  

* Risk Factors and Associated Conditions for Pulmonary Arterial Hypertension

* Genetic Factors

* Underlying Lung Disease

* Obstructive sleep apnea [Obstructive sleep apnea - Chronic]

* Thromboembolic stroke

* Eisenmenger's syndrome

* Anorexigenic Agent Use

* Central Nervous System Stimulants

* Scleroderma [Scleroderma - Chronic]

* HIV infection

* Portal hypertension

* Thrombocytosis

* Hemoglobinopathy

* Osler hemorrhagic telangiectasia syndrome

* Selective Serotonin Reuptake Inhibitors and Persistent Pulmonary Hypertension of the Newborn

 

Findings  

* Cardiovascular finding

* Syncope

* Angina

* Dyspnea on exertion

* Abnormal breath sounds

* Fatigue

* Impaired exercise tolerance

* Gastrointestinal symptom

* Liver pulsatile

* Cyanosis

* Dermatological finding

 

Tests  

 

All patients with a clinical suspicion of pulmonary arterial hypertension  

* Echocardiography: It is recommended that all individuals with either suspected or established pulmonary hypertension have a comprehensive echocardiographic evaluation .

 

All patients with suspected pulmonary hypertension to confirm the presence of pulmonary hypertension, establish the specific diagnosis, and determine the severity of disease  

* Cardiac catheterization: Hemodynamic studies are required to establish the diagnosis of pulmonary hypertension and to determine the hemodynamic classification .

 

Supportive test for patients with suspected pulmonary hypertension to screen for associated cardiac problems  

* 12 lead ECG: The ECG can be used as a supportive diagnostic test because pulmonary hypertension results in right ventricular hypertrophy and right heart dilation .

 

Supportive test for patients with suspected pulmonary hypertension  

* Plain chest X-ray: Although typically normal, a chest x-ray may reveal abnormal features supportive of a diagnosis of pulmonary hypertension and lead to diagnoses of underlying or alternative diseases .

 

To exclude or characterize the contribution of underlying lung disease in the initial evaluation of all patients with pulmonary hypertension  

* Pulmonary function test: Pulmonary function testing is a necessary part of the initial evaluation of all patients with pulmonary hypertension .

 

To rule out chronic thromboembolic pulmonary hypertension (CTEPH) in patients with unexplained pulmonary hypertension  

* VQ - Ventilation perfusion scan: Ventilation-perfusion scintigraphy is an important part of the assessment because chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially curable cause of pulmonary hypertension .

 

For preoperative confirmation of chronic thromboembolic pulmonary hypertension (CTEPH)  

* Arteriography of pulmonary arteries: Pulmonary angiography is required both to confirm chronic thromboembolic pulmonary hypertension and to assess whether the patient is a candidate for surgical intervention .

 

To assess for the presence of connective tissue disease and HIV infection in all patients with unexplained pulmonary arterial hypertension  

* Serologic test: Due to the strong association of HIV and connective tissue diseases with pulmonary hypertension, testing for these diseases may be indicated in some patients .

 

To provide benchmarks for disease severity, response to therapy, and progression  

* Exercise tolerance test: Assessment of exercise capacity is an essential component of the evaluation process of patients with known pulmonary hypertension .

 

Differential Diagnosis  

* Heart failure

* Heart valve disorder

* Pulmonary embolism - Acute

* Interstitial lung disease - Chronic

* Chronic obstructive pulmonary disease - Chronic

* Asthma

* Acute coronary syndrome

* Constrictive pericarditis

* Aspiration pneumonia - Acute

 

Treatment  

 

Drug Therapy  

 

 

Pulmonary arterial hypertension  

 

EPOPROSTENOL SODIUM  

Adults: initial, 2 ng/kg/minute IV; titrate upward in increments of 2 ng/kg/min every 15 minutes or longer until dose-limiting effects or tolerance develops; should dose-limiting effects occur, gradually decrease infusion rate in increments of 2 ng/kg/min every 15 minutes; avoid abrupt withdrawal

 

ILOPROST  

Adults: initial inhaled dose is 2.5 mcg; if tolerated, increase to 5 mcg administered 6 to 9 times per day (no more than every 2 hours) during waking hours, according to individual need and tolerability (maximum 45 mcg daily [5 mcg, 9 times per day])

 

BOSENTAN  

Adults: initial, 62.5 mg orally twice daily for 4 weeks; maintenance, increase up to 125 mg orally twice daily

 

 

Pulmonary arterial hypertension, New York Heart Association (NYHA) class II-IV symptoms  

 

TREPROSTINIL SODIUM  

Adults: initial, 1.25 ng/kg/minute continuous subQ (preferred) or IV infusion; decrease to 0.625 ng/kg/minute if initial dose cannot be tolerated; increase dose in increments of no more than 1.25 ng/kg/minute per week for the first 4 weeks and then no more than 2.5 ng/kg/minute per week for remaining duration, depending on clinical response

 

Procedural Therapy  

 

To maintain oxygen saturations above 90% at all times in patients with pulmonary hypertension and chronic hypoxemia  

* Oxygen therapy: In patients with chronic hypoxemia, supplemental oxygen, including ambulatory oxygen therapy, is indicated to maintain adequate arterial oxygen saturation .

 

Patients with advanced pulmonary hypertension  

* Pulmonary rehabilitation: Respiratory and physical training has the potential of being a safe and effective adjunct therapy in patients with advanced pulmonary hypertension .

 

In select patients with pulmonary hypertension unresponsive to medical management  

* Atrial septostomy operation: Current indications for atrial septostomy include the failure or unavailability of medical therapy, bridging to transplantation, or palliation .

 

Patients with operable chronic thromboembolic pulmonary hypertension (CTEPH)  

* Thromboendarterectomy: Pulmonary thromboendarterectomy may provide a potential cure in patients with operable chronic thromboembolic pulmonary hypertension .

 

Patients with pulmonary arterial hypertension whose prognosis remains poor despite medical therapy  

* Transplant of lung: Pulmonary arterial hypertension patients with NYHA functional class III and IV symptoms should be referred to a transplant center for evaluation and listing .