What are the other Names for this Condition? (Also known as/Synonyms)

• Pulmonary Hypertension and Chronic Kidney Disease
• Pulmonary Hypertension due to Chronic Kidney Failure
• Pulmonary Hypertension due to Chronic Renal Failure on Dialysis

What is Pulmonary Hypertension due to Chronic Renal Failure? (Definition/Background Information)

• Pulmonary hypertension (PH) is a disorder characterized by very high blood pressure (above normal) in the lungs due to a variety of causes. It should not be confused with systemic hypertension, otherwise known as ‘high blood pressure’
• The pulmonary blood vessels (arteries and veins) are usually a “low pressure” system, which means the blood pressure within the lung blood vessels is much lower than the rest of the body
• This elevated pulmonary blood pressure causes the right side of the heart to work harder, placing an increased burden on the heart. It is often caused by various lung and heart disease but can be associated with many other conditions too
• The World Health Organization (WHO) has clinically classified pulmonary hypertension according to certain groups. Pulmonary Hypertension due to Chronic Renal Failure forms part of WHO group 5 (sub group 5.4. Other disorders)
• The association of chronic renal failure with pulmonary hypertension is not uncommon. Chronic renal failure or chronic kidney disease (CKD) is a gradual loss of kidney function characterized by a decreased ability of the kidneys to remove waste and excess fluid from blood. Some of the factors that increase the risk for pulmonary hypertension in patients with CKD include severe anemia, left-sided cardiac failure, and fluid retention (edema)
• The signs and symptoms of Pulmonary Hypertension due to Chronic Renal Failure may include shortness of breath, chest pain, fatigue, and dizziness. The signs and symptoms also depend on the underlying chronic renal failure, and may include loss of body muscle, swelling of the limbs, fatigue, and cognitive function decline
• Following a diagnosis of Pulmonary Hypertension due to Chronic Renal Failure, the treatment measures may involve the use of medications, such as calcium channel blockers, and bringing about certain lifestyle modifications, among others. Chronic kidney disease management involves evaluation of the stage and progression of the condition, including treatment of the conditions caused by CKD
• The prognosis of Pulmonary Hypertension due to Chronic Renal Failure may be improved if the condition is diagnosed promptly and treated appropriately. However, the overall prognosis depends on several factors including on the severity of the underlying chronic renal failure; it may vary from one individual to another, but is generally poor

Who gets Pulmonary Hypertension due to Chronic Renal Failure? (Age and Sex Distribution)

• The age, gender, and racial/ethnic distribution of Pulmonary Hypertension due to Chronic Renal Failure depends on the underlying chronic renal failure causing PH
• Anywhere between 10-50% of end-stage renal failure patients are known to have concurrent PH, especially those on dialysis
• Both males and females are equally affected
• Worldwide, individuals of all racial and ethnic groups may be affected. However, CKD is more prevalent in African-American, Hispanic American, Asian, and Indian American populations

What are the Risk Factors for Pulmonary Hypertension due to Chronic Renal Failure? (Predisposing Factors)

The risk factors for Pulmonary Hypertension due to Chronic Renal Failure include:

• Calcification and stiffening of the blood vessels
• Endothelial dysfunction
• Exposure to dialysis membranes
• Increased calcium phosphate product
• Left-sided heart failure
• Presence of an arteriovenous fistula
• Severe anemia
• Sleep apnea
• Volume overload/fluid retention

The risk factors for chronic renal failure include:

• Uncontrolled diabetes
• High blood pressure
• Cardiovascular disease
• Smoking
• Obesity
• A family history of kidney disease
• Abnormal kidney structure
• Older age

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Pulmonary Hypertension due to Chronic Renal Failure? (Etiology)

Pulmonary hypertension is caused by an increased blood pressure within the blood vessels of the lung. Pulmonary Hypertension due to Chronic Renal Failure is associated with the underlying chronic renal failure; it develops secondary to the condition.

• Volume overload secondary to chronic renal failure leads to increased work of the right-side of the heart and contributes to PH
• Chronic renal failure contributes to a prothrombotic environment by loss of antithrombin III, resulting in a potentially coagulable state, increasing the risk for PH

What are the Signs and Symptoms of Pulmonary Hypertension due to Chronic Renal Failure?

The signs and symptoms of Pulmonary Hypertension due to Chronic Renal Failure depends on a set of several factors that include age of the individual, overall health of the individual, and associated health conditions. The signs and symptoms can be directly related to pulmonary hypertension, and to the underlying chronic renal failure.

The common signs and symptoms of pulmonary hypertension include:

• Progressive shortness of breath (especially while exercising), is the most common symptom
• Fatigue (frequent tiredness)
• Chest pain
• Dizziness, fainting
• Swelling of the ankles/legs
• Palpitations
• Bluish lips and skin, observed during the later stages
• Irregular heartbeat (arrhythmias)
• Fluid in the abdomen (ascites)

The signs and symptoms related to chronic renal failure depend on its severity, and may include:

• Malnutrition
• Muscle weakness; loss of body muscle
• Peripheral edema - swelling of the limbs and face
• Pulmonary edema - presence of fluid in the lungs leading to breathing difficulties
• Anemia, due to low red blood cell count
• Fatigue; increased drowsiness/somnolence
• Anorexia; loss of hunger
• Nausea, vomiting, and diarrhea
• Dry skin, severe itching (pruritus), skin discoloration and bruising (ecchymosis)
• Failure to thrive
• Erectile dysfunction and decreased libido
• Abnormal absence of menstruation
• Tendency to bleed

How is Pulmonary Hypertension due to Chronic Renal Failure Diagnosed?

To diagnose Pulmonary Hypertension due to Chronic Renal Failure, a diagnosis of pulmonary hypertension (PH) must first be established. This involves certain preliminary diagnostic procedures. Depending on the results of these tests, confirmation will be made with a right-heart catheterization.

The preliminary procedures may include:

• A complete physical examination of the patient 
• A thorough checking of the patient’s medical history and a detailed checking of the family history of the patient
• Blood tests:
  • Blood tests help rule out other diseases
  • They also help in checking the blood oxygen levels
  • The measurement of brain natriuretic peptide (BNP) can be used to assess the strain on one’s heart
• Chest X-ray: Chest X-rays can reveal structural signs of pulmonary hypertension by identifying changes in the pulmonary arteries or enlargement of the right side of the heart
• Electrocardiogram (ECG): An electrocardiogram checks the electrical impulses of the heart. There are certain identifiable patterns on an ECG that may indicate pulmonary hypertension. However, ECG is not specific enough to diagnose the condition by itself, so a combination of tests may be recommended by the healthcare provider
• Echocardiogram: In this procedure, a sonogram of the heart is taken and used to measure overall functioning as well as measure the pressure within the chambers of the right heart. An echocardiogram is also often times used to monitor a patient’s condition after diagnosis and during treatment
• Pulmonary function tests: These tests help measure the quality of breathing and check the functioning of the lungs (such as how much air is breathed in and out, as well as the quality of oxygen exchange)
• Exercise tolerance test (six-minute walk test): This helps to measure the patient’s ability to exercise
• Nuclear scan (ventilation/perfusion scan or V/Q scan): This tool helps identify any new or chronic blood clots in the vessels of the lungs that could be causing pulmonary hypertension

A diagnosis of chronic renal failure may additionally involve:

• Lab tests that include complete blood count (CBC), metabolic panel, urine tests, lipid profile, among others
• Radiological studies that include renal ultrasound, CT and MRI scan of the kidney, etc.
• Kidney biopsy, if necessary

The gold standard for pulmonary hypertension diagnosis and management is right-heart catheterization and acute vasodilator challenge.

• Right-heart catheterization:
  • If pulmonary hypertension is suspected based off preliminary tests and procedures, a right-heart catheterization test is ordered to help confirm the diagnosis
  • This test can accurately quantify right-heart pressures (measure the pressure within the chambers of the right heart), especially the pressure inside the pulmonary arteries
  • During this procedure, a very small catheter is inserted into a large vein (either within the patient’s groin or neck) and passed into the patient’s heart and vasculature to measure the internal blood pressures 
• Vasodilator study (acute vasodilator challenge):
  • While this test is not used to necessarily “diagnose” pulmonary hypertension, it is used to evaluate the patient for possible therapeutic management
  • Like right-heart catheterization, a catheter is placed within the pulmonary artery to test for vasodilation (or relaxation) in response to a class of medications called calcium channel blockers (CCBs)
  • The response and dosing of CCBs can be evaluated with this procedure

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Pulmonary Hypertension due to Chronic Renal Failure?

The complications of Pulmonary Hypertension due to Chronic Renal Failure depends on a set of several factors that include the age of the individual, overall health of the individual, underlying chronic renal failure, and promptness of diagnosis. 

Following are the possible complications that may arise due to the condition:

• Right-sided heart failure with hepatic congestion (due to deposition of stones in the liver)
• Pedal edema: Swelling of the leg or ankle
• Pleural effusions: Building-up of excess fluid around the lungs
• Worsening dyspnea (shortness of breath) upon exertion

The complications related to chronic renal failure may include:

• Impaired immunity resulting in increased susceptibility to infections
• Decline of cognitive function
• Increased potassium level in blood
• Inflammation of the heart membranes
• Impotence
• Severe gastrointestinal tract symptoms

How is Pulmonary Hypertension due to Chronic Renal Failure Treated?

The treatment of Pulmonary Hypertension due to Chronic Renal Failure depends on a set of several factors that include the severity of the signs and symptoms, age of the individual, and overall health of the individual. The treatment of chronic renal failure may involve renal replacement therapy, protein restriction, and symptomatic treatments.

PH associated with chronic renal failure is best treated at a medical center with appropriate expertise. Several medical treatments are highlighted below:

• Conventional medical therapies:
  • Calcium channel blockers (CCBs): These are a group of medications that help vasodilate (or relax) the arteries. However, CCBs are only appropriate for patients demonstrating a favorable response to the vasodilator study
  • Inotropic agents: These are medications that assist in the pumping of the heart 
  • Diuretics, salt limitation, and weight monitoring may be recommended, to limit excess strain on the heart
  • Supplemental oxygen may help an individual meet the ‘oxygen needs’ for normal daily activities
  • Blood thinners: These medications help prevent blood clots, especially in the lung blood vessels
  • Treating underlying diseases or conditions
• Oral, inhaled, subcutaneous, or intravenous treatment options:
  • Endothelin receptor antagonists (ERAs) help in preventing pulmonary blood vessels from narrowing which helps keep the pressures towards normal levels
  • Phosphodiesterase inhibitors (PDE 5 Inhibitors), prostacyclin analogues, and soluble guanylate cyclase (sGC) stimulators, all aid in allowing vessels of the lungs to vasodilate (or relax)
• Additional treatment options may include:
  • Lifestyle modifications, such as nutrition, exercise, avoiding tobacco, and limiting alcohol consumption, are beneficial
  • Judicious exercising may be effective in limiting deconditioning (by building stamina), improving the quality of life, and exercising capacities. Isometric exercises, such as heavy weightlifting, should be avoided
  • Other treatments, depending on the etiology (cause) of pulmonary hypertension, may include various cardiothoracic procedures
  • Lung transplantation may be required with advanced forms of the disorder

How can Pulmonary Hypertension due to Chronic Renal Failure be Prevented?

Pulmonary Hypertension due to Chronic Renal Failure may be prevented or controlled if appropriate treatment of the underlying chronic renal failure is considered.

• Chronic renal failure due to certain causes, such as high blood pressure, diabetes, excessive use of NSAIDS, and atherosclerosis, may be prevented by proper treatment of the underlying disease/condition and with good lifestyle regimen and compliance
• If the kidneys are affected due to causes that include vasculitis or glomerulonephritis, then it may not be preventable

The non-modifiable risk factors for pulmonary hypertension (PH), such as age, gender, and genetics (family history), cannot be controlled; and therefore, it may not be possible to prevent PH that develops from these factors. However, an early and effective treatment is critical and imperative.

• For those with a pre-existing condition that is a risk factor for pulmonary hypertension, seeking medical attention at the onset of symptoms may help avoid worsening of the condition and complications 
• Avoidance of recreational drugs, various toxic agents, and inappropriate weight loss drugs is important

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis Pulmonary Hypertension due to Chronic Renal Failure? (Outcomes/Resolutions)

• The prognosis of Pulmonary Hypertension due to Chronic Renal Failure differs from one individual to another, depending on its severity and on the underlying extent of chronic renal failure. Chronic renal failure generally progresses to end-stage renal disease (ESRD), which results in worse prognosis
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications. Typically, the prognosis may be assessed on a case-by-case basis, but is mostly poor

Additional and Relevant Useful Information for Pulmonary Hypertension due to Chronic Renal Failure:

The following DoveMed website links are useful resources for additional information:

https://www.dovemed.com/diseases-conditions/end-stage-kidney-disease/

https://www.dovemed.com/diseases-conditions/chronic-kidney-disease/

https://www.dovemed.com/diseases-conditions/acute-kidney-failure/