Portopulmonary hypertension is an increase in blood pressure in the pulmonary circulation due to portal hypertension. This, in turn, is usually the result of cirrhosis of the liver.
What is portopulmonary hypertension?
In portopulmonary hypertension, hypertension of the pulmonary artery occurs as a result of portal hypertension. Pulmonary hypertension refers to increased vascular resistance in the arterial blood vessels of the lungs. This increased vascular resistance leads to increased blood pressure. See howsmb for HVS Definition and Meaning.
Pulmonary hypertension occurs as a complication of portal hypertension. In portal hypertension, the blood pressure in the portal vein (vena portae) is increased to more than 12 mmHg. The normal pressure in the portal vein is 3 to 6 mmHg. The portal vein is the blood vessel that carries the oxygen-poor and nutrient-rich blood from the unpaired abdominal organs to the liver.
The causes of portopulmonary hypertension are similar to those of portal hypertension. The disease usually arises within the liver. The most common cause is cirrhosis of the liver. 0.25 to 2 percent of all patients with liver cirrhosis develop portopulmonary hypertension. Liver cirrhosis is the end stage of many liver diseases. Typically, cirrhosis develops over several years or even decades.
Almost all chronic liver diseases end sooner or later in liver cirrhosis. In Europe, viral hepatitis and alcohol abuse are among the most common causes. In cirrhosis of the liver, the liver tissue that dies due to liver disease is replaced with connective tissue. This process is called fibrosis. More than half of the functional liver tissue can be affected by the remodeling. As a result, blood flow to the liver is restricted.
The blood accumulates in the area of the portal vein in front of the liver. This leads to high blood pressure within the liver (portal hypertension). It has not yet been clearly clarified why portal hypertension also leads to an increase in blood pressure in the lungs. Irritation of the inner skin of the vessels may occur due to increased blood flow in the lungs.
Microthrombi in the small pulmonary arteries are also discussed as a causal factor. These microthrombi can occur due to liver-related hypercoagulability. Portopulmonary hypertension can also occur as a complication of liver transplantation.
Symptoms, Ailments & Signs
Pulmonary hypertension puts a lot of strain on the right heart, as it constantly has to pump against the increased pressure. This pressure load is to be compensated by an enlargement of the heart muscle (right heart hypertrophy). The hypertrophy of the heart due to pulmonary hypertension is also known as cor pulmonale.
Patients with portopulmonary hypertension have both pulmonary and hepatic symptoms. They are severely restricted in their physical performance and suffer from shortness of breath, coughing, circulatory disorders up to and including fainting, angina pectoris, fatigue, peripheral edema, a blue discoloration of the skin or Raynaud’s syndrome.
In Raynaud’s syndrome, vascular spasms occur, which are associated with reduced blood flow to the toes or fingers. Valve insufficiency of the right heart valve usually occurs together with pulmonary hypertension. If left untreated, cor pulmonale leads to right heart failure. Signs of right heart failure are congested veins in the neck and edema, ascites and swollen spleen. Increased nocturnal urination, cold extremities and tachycardia can also be signs of this.
Eventually, complete heart failure occurs, resulting in death. The symptoms of pulmonary hypertension are accompanied by the symptoms of portal hypertension. In pulmonary hypertension, bypass circuits form. As a result, the veins appear very prominent on the anterior abdominal wall. The star-shaped visible veins starting from the navel are called caput medusae.
Another bypass circuit runs through the esophagus. This is where the so-called esophageal varices form. These can easily perforate through ingested food. Such a perforation is life-threatening due to the profuse bleeding.
Diagnosis & course of disease
The diagnosis begins with a detailed medical history and a detailed physical examination. The liver values in the blood are then first determined in the laboratory. These include GOT, GPT, GLDH and y-GT. Furthermore, the vitamin K-dependent coagulation factors (I, II, IV and VII) as well as protein S, protein C and antithrombin III are determined.
Increased or decreased values indicate a functional impairment of the liver. In order to be able to better assess the condition of the lungs and liver, an X-ray examination of the chest and abdomen is carried out. A right heart catheter examination with the measurement of the pulmonary arterial pressure can confirm the diagnosis of portopulmonary hypertension. ECG and echocardiography provide information about the extent of cardiac stress. The hepatorenal syndrome must be excluded in the differential diagnosis. Here, however, the arterial lack of oxygen is more in the foreground.
Portopulmonary hypertension is already a serious complication of portal hypertension. Since this in turn is often caused by cirrhosis of the liver, other complications can occur which accompany portopulmonary hypertension but are not caused by it. These include abdominal wall varices, esophageal varices, varicose veins in other parts of the body, accumulation of fluid in the abdomen (ascites), enlarged spleen and hepatic encephalopathy.
Furthermore, portopulmonary hypertension also occurs as a serious complication after liver transplantation. It is characterized by an enlargement of the right heart, which develops as a result of the constant strain on the right heart in portal hypertension (cor pulmonale). Heart valve damage can develop from this, which subsequently leads to what is known as tricuspid insufficiency. Tricuspid regurgitation is a special form of heart failure.
It is characterized by completely different courses. However, there is always a risk of total overloading of the heart, which can lead to a rapid worsening of heart failure. Severe tricuspid insufficiency manifests itself in cardiac arrhythmia, leg edema, and congestion in the neck veins and liver.
This creates a vicious circle in which, among other things, portopulmonary hypertension caused by cirrhosis of the liver causes even more damage to the liver via the development of tricuspid insufficiency and can thus lead to liver failure. In rare cases, secondary pulmonary embolism can also lead to sudden death. In severe cases, the cardiac arrhythmias can also lead to sudden cardiac death.
When should you go to the doctor?
Shortness of breath, liver pain, exhaustion and other typical signs of portopulmonary hypertension require medical evaluation. People suffering from cirrhosis of the liver should inform the doctor responsible about the symptoms mentioned. By examining the liver, the doctor can quickly determine whether portopulmonary hypertension is present and take the necessary measures. Early treatment can greatly improve the chances of a speedy recovery. Therefore, the first signs of hypertension should be observed and presented to the doctor the next day at the latest if they have not subsided by then.
Portopulmonary hypertension is treated by a liver disease specialist. Inpatient treatment is usually necessary. If the symptoms occur after a liver transplant, there is an acute danger to life. The patient must immediately inform the doctor in charge. Other risk groups are chronic liver disease and people who suffer from other diseases of the internal organs. People with an immune deficiency or cancer in the liver or spleen are also among the risk groups and should see a specialist immediately if they experience the symptoms mentioned.
Treatment & Therapy
The treatment of portopulmonary hypertension aims at treating the underlying disease. Liver cirrhosis is irreversible. However, the progression of the disease can be stopped if you abstain from all liver-toxic substances. Patients should avoid alcohol in particular. A balanced diet, a reduction in protein intake and the substitution of nutrients can also alleviate the symptoms.
Liver transplantation may be necessary for severe cirrhosis of the liver. The causal therapy is supported by drug-based, symptom-oriented therapy. For this purpose, vasodilating substances such as prostaglandin analogues, ET-1 receptor antagonists and calcium antagonists are administered. If necessary, administration of ß-blockers may also be indicated.
There is no direct way to prevent portopulmonary hypertension. It can only be prevented if the underlying disease is recognized and treated as early as possible. In the best case, of course, the underlying disease itself should be prevented. Since the main risk factor for developing liver cirrhosis is alcohol abuse, abstaining from alcohol can prevent cirrhosis in most cases.
Portopulmonary hypertension can be treated in the follow-up phase by conscious abstinence. In this way, the progression of the disease can be slowed down, sometimes even completely contained. Avoiding alcohol makes you feel better. A varied, vitamin-rich diet is recommended for those affected.
Among other things, a reduced protein intake helps to alleviate the symptoms. Thanks to healthy replacement products with nutrients, the body still gets enough vital substances. As a supplement and to connect to the actual therapy, doctors often recommend vasodilating substances.
This means that aftercare also serves as a precautionary measure. However, the disease can only be prevented to a limited extent. Health-conscious behavior significantly reduces the risk. The main cause of the symptoms can therefore be strongly influenced. The supply of sufficient vitamins improves the immune system at the same time and the quality of life increases.
Exercise is also helpful, but those affected should not overestimate themselves and avoid overexertion. Stress from a lot of work or interpersonal crises can also have a negative impact. It is therefore important to reduce such factors through relaxation techniques and to remain as relaxed as possible.
You can do that yourself
Patients with portopulmonary hypertension should refrain from drinking alcohol altogether. The supply of food, especially in restaurants, must be checked for its ingredients before consumption. Even small amounts of alcohol can lead to complications and an increase in symptoms. Addicts are advised to seek withdrawal as soon as possible. This is the only way to slow down the progression of the disease.
In addition to medical care, the immune system must be supported independently. A vitamin-rich diet and a balanced diet are important. In dealing with the disease, the organism needs sufficient defenses. In addition to a healthy food intake, these can be mobilized by the supply of sufficient oxygen and exercise. In all physical activities, the body’s own limits must be observed and overexertion avoided.
Situations in which the person concerned is exposed to emotional stress are also harmful. These contribute to an increase in blood pressure and worsen the general state of health. Interpersonal conflicts should therefore be resolved as quickly as possible or should be avoided. A stable and safe social environment is important in overcoming all the adversities of the disease. Mental training and various relaxation techniques help to reduce built-up stressors. These can be used independently according to the needs of the patient.