Pulmonary Hypertension: Symptoms, diagnosis, and treatment
PULMONARY HYPERTENSION
Pulmonary hypertension (PH) is a general diagnosis indicating high blood pressures in the lung arteries. These arteries carry oxygen-poor blood from your heart to your lungs. PH is dangerous because it disrupts the flow of blood through heart and lungs. High blood pressure in your pulmonary arteries causes these arteries to become narrow. As a result, your heart must work harder to pump oxygen-poor blood to your lungs. Over time, if left untreated, it can damage the heart.
What are the types of PH?
The World Health Organization classifies PH into 5 groups based on the cause:
PAH makes your pulmonary arteries become narrow, thick or stiff. Less blood can flow through, which raises the pressure in your pulmonary arteries.
2
PH due to left-sided heart disease
Heart failure, valvular heart disease, Congenital and acquired cardiovascular conditions leading to postcapillary pulmonary hypertension
The left side of your heart pumps out blood to your entire body. If there’s a problem on this side of your heart, it affects the right side of your heart and your entire pulmonary circuit. Blood backs up in your heart, raising the pressure in your pulmonary arteries.
3
PH due to lung disease or hypoxia
Obstructive or restrictive lung disease, lung diseases with mixed restrictive and obstructive patterns, Hypoventilation syndromes, Hypoxia without lung disease, Developmental lung disorders
Certain lung problems cause stiffness of arterial walls and reduced blood flow raising the pressure in your pulmonary arteries.
4
PH due to blockages in your lungs
Chronic thromboembolic pulmonary hypertension, Other pulmonary artery obstructions
Blood clots or scars from blood clots prevent your blood from flowing normally through your lungs. This puts more stress on the right side of your heart and raises pulmonary blood pressure.
The exact mechanisms for how the condition triggers PH aren’t always clear.
How common is PH?
We don’t know exactly how many people around the world have pulmonary hypertension. But some estimates show PH may affect 1 in 100 people. This means 50 million to 70 million people are living with PH.
PH is even more common among older adults. Around the world, about 1 in 10 adults over age 65 have PH. PH affects:
Nearly 100% of people with severe mitral valve disease
About 65% of people with aortic valve disease
Up to 30% of people with scleroderma
About 20% to 40% of people with sickle cell disease
The symptoms of pulmonary hypertension develop slowly. You may not notice them for months or even years. Symptoms get worse as the disease continues. Symptoms of PH include:
Shortness of breath. It may first start during exercise and eventually happen at rest.
Blue or grey skin. Depending on skin color, these changes may be harder or easier to see.
The evaluation process should include a comprehensive medical and family history, physical examination, monitoring of blood pressure, heart rate, oxygen saturation, and
Laboratory tests: should include hematology studies, renal function tests, liver function tests (LFTs), iron profiles, and thyroid studies.
Electrocardiogram: A normal ECG does not exclude the diagnosis of pulmonary hypertension. However, an abnormal ECG may indicate severe disease, especially if QRS and QTc are prolonged.
Chest X-ray: Chest radiography may reveal underlying pulmonary hypertension, such as right atrial enlargement, pulmonary artery enlargement, peripheral vessel pruning, and a water bottle-shaped cardiac silhouette. Signs of left heart diseaselike Kerley B lines, pleural effusions, and left heart enlargement may also be present. Patients with lung disease may have diaphragmatic flattening, hyperlucency, volume loss, or reticular opacifications on x-ray, depending on their condition. A normal chest X-ray does not rule out pulmonary hypertension.
Pulmonary function tests and arterial gases: Most patients with PAH have decreased carbon monoxide diffusion capacity (DLCO). A DLCO of less than 45% is associated with poor outcomes. Patients with PAH usually have a low normal or slightly low partial pressure of oxygen (PaO2).
Chest CT and digital subtraction angiography: helps to identify interstitial lung diseases and measure enlarged arteries or heart chambers.
Echocardiographic assessment should only be used to estimate pulmonary hypertension probability. RHCis used for diagnostic confirmation and therapeutic guidance.
Cardiopulmonary exercise testing: In patients with PAH, a low end-tidal partial pressure of carbon dioxide, high ventilatory equivalent for carbon dioxide, low oxygen pulse, and low peak oxygen uptake are typically seen.
Cardiac MRI: is an incredibly powerful tool that accurately assesses atrial and ventricular function and morphology. This modality can also measure blood flow through the vena cava, pulmonary artery, and aorta, allowing for stroke volume quantification. The test is sensitive for detecting early pulmonary hypertension but does not reliably estimate pulmonary artery pressures.
Abdominal ultrasonography: The main reason for obtaining an abdominal ultrasound is to detect liver abnormalities, portal hypertension, and kidney injury that may arise from chronic pulmonary hypertension. Ultrasonography can help assess the extent of the collateral damage to these organs.
Right heart catheterization: not only confirms the diagnosis of PH but also yields enormous information, including right- and left-sided filling pressures, pulmonary artery pressure, PAWP, PVR, and cardiac output.
Ventilation-perfusion scanning: to rule out CTEPH (chronic thromboembolic pulmonary hypertension) in patients with pulmonary hypertension.
How is PH treated?
Medication
Vasodilators like epoprostenol (Flolan, Veletri), treprostinil (Remodulin, Tyvaso, others), iloprost and selexipag (Uptravi) can be either injected intravenously or given orally.
Soluble guanylate cyclase stimulators like riociguat (Adempas) relaxes the pulmonary arteries and lowers pressure in the lungs.
Endothelin receptor antagonists such as bosentan (Tracleer), macitentan (Opsumit) and ambrisentan (Letairis) reverse the effect of a substance in the walls of blood vessels that causes them to narrow.
Phosphodiesterase 5 (PDE5) inhibitors such as sildenafil (Revatio, Viagra) and tadalafil (Adcirca, Alyq, Cialis) may be used to increase blood flow through the lungs. These medicines also are used to treat erectile dysfunction.
High dose calcium channel blockers such as amlodipine (Norvasc), diltiazem (Cardizem, Tiazac, others) and nifedipine (Procardia) help relax the muscles in the walls of blood vessels.
Anti-coagulants or blood thinners such as warfarin, help prevent blood clots.
Digoxin helps the heart beat stronger and pump more blood. It can help control irregular heartbeats.
Diuretics help the kidneys remove excess fluid from the body. This reduces the amount of work the heart has to do. Diuretics also may be used to reduce fluid buildup in the lungs, legs and belly area.
Oxygen therapy may be suggested if you live at a high altitude or have sleep apnea. Some people with pulmonary hypertension need oxygen therapy all the time.
Surgery
If medicines do not help control the symptoms of pulmonary hypertension, surgery may be recommended.
In an atrial septostomy, a doctor creates an opening between the upper left and right chambers of the heart. The opening reduces the pressure on the right side of the heart. Potential complications include irregular heartbeats called arrhythmias.
