Introduction
Riociguat (trade name: Adempas) has been approved in Germany since March 2014 for the treatment of pulmonary hypertension (high blood pressure) in adults. It can be used alone or in combination with other blood-pressure-lowering (antihypertensive) medications.
The right side of the heart pumps blood that is low in oxygen through the pulmonary artery into the lungs. The blood picks up oxygen in the lungs and then travels through the pulmonary vein to the left side of the heart. From there, oxygen-rich blood is pumped into the body. This part of the blood circulatory system is called pulmonary circulation. In chronic thromboembolic pulmonary hypertension (CTEPH), the pulmonary (lung) vessels are narrowed, increasing the blood pressure within the pulmonary circulation. This makes it harder for the heart to pump blood through the lungs. As a result, there is more strain on the heart, less oxygen is absorbed by the lungs, and too little oxygen reaches the body. CTEPH may occur if people have frequently recurring pulmonary embolisms and the blood clots don't fully dissolve, causing the pulmonary vessels to become narrower.
CTEPH has four stages:
- Stage 1: Patients have an increased pulmonary blood pressure, but have no symptoms during normal physical activity.
- Stage II: During physical activity, patients have symptoms such as trouble breathing, fatigue, chest pain or feeling faint. These symptoms stop when resting.
- Stage III: Even light physical activity causes severe symptoms, but there are no symptoms at rest.
- Stage IV: Symptoms occur even at rest and physical activity is severely limited. There is also a risk of heart failure.
Riociguat is a treatment option for people with functional class II or III CTEPH. The drug aims to widen the blood vessels and decrease the strain on the heart.
