Right-Sided Endocarditis - Causes, Symptoms, Diagnosis, and Treatment

Introduction

Endocarditis is usually a result of a bacterial infection that causes inflammation of the lining of the heart, the valves, and the chambers. If not treated on time it can be a fatal disease. Right-sided infective endocarditis is not too prevalent. It accounts for almost 5-10 % of all cases of Infective Endocarditis. The symptoms of endocarditis develop slowly over time or may remain asymptomatic also. In earlier stages, the symptoms seem to be similar to some other diseases that’s why it remains undiagnosed for a longer time.

What Is Endocarditis?

Endocarditis is the inflammation of the heart's inner lining or maybe the heart's chambers due to bacterial infection. This happens when bacteria(often Staphylococcus groups) enter the bloodstream and reach the heart, attacking the heart's inner lining or chambers of the heart. Infective endocarditis is also called bacterial endocarditis (BE) or subacute bacterial endocarditis (SBE). People with endocarditis often experience heart murmur (abnormal heart sound), pale skin, fever, pain, tenderness, swelling, nausea, vomiting, etc.

What Is Right-Sided Endocarditis?

• Right-sided endocarditis or right-sided infective endocarditis refers to the involvement of the tricuspid or pulmonic valve. Around 5-10 % of cases account for right-sided infective endocarditis of all cases of infective endocarditis.

• The main cause of right-side infective endocarditis is intravenous drug use, use of intracardiac devices, and central venous catheters. Its presence is also noted in people who are on dialysis or suffer from congenital heart disease or are in immunocompromised states.

• The endocardium is the covering layer of the heart. When this layer is affected it is called infective endocarditis. If this layer gets damaged or is not treated on time it may result in the failure of the heart. The prognosis for right-sided endocarditis is considered to be good as compared to left-sided endocarditis. This mortality rate is low ranging from 3-30%

What Are the Symptoms Associated With Right-Sided Endocarditis?

The symptoms associated with right-sided infective endocarditis are-

• Cough.

• Dyspnea (shortness of breath or intense tightening in the chest).

• Hemoptysis (expectoration of blood or blood-tinged sputum from the lungs).

• Chest pain.

• High fever.

What Are the Causes of Right-Sided Endocarditis?

The causes of right-sided endocarditis are -

• Due to intravenous drug use.

• Due to the use of the catheter (a tube that is inserted into the bladder to pass the urine freely).

• Due to the use of inter-cardiac devices.

• Staphylococcus aureus is the main organism that results in causing right-sided endocarditis in most cases (60-90 %).

• Streptococcal and coagulase-negative Staphylococcal infections are also the causes in some cases.

• S. pneumoniae is also seen to cause right-sided endocarditis, although it is more common in the left side of the heart with right-sided endocarditis.

• Congenital heart diseases may also result in causing right-sided endocarditis.

• People on dialysis may also develop it.

How Is Right-Sided Endocarditis Diagnosed?

In most cases, right-sided endocarditis remains undiagnosed due to the less severity of the symptoms. Right-sided endocarditis can be diagnosed with the help of-

• Blood test- It can be diagnosed with the help of a blood test. The high number of white blood cells and C-reactive protein can help in diagnosing the infection caused by Staphylococcus aureus.

• Blood cultures- With this the bacteria or microorganisms associated with infective endocarditis are diagnosed. This test allows for isolating a particular bacteria which causes infective endocarditis.

• Radiography- It can be done to check for the conditions caused due to infective endocarditis such as cardiomegaly, pulmonary emboli, or pleural effusion.

• Echocardiogram- It usually shows the condition of the heart. Also, known as ultrasound of the heart. This shows the growth(presence of vegetation on the valve), abscess(hole), regurgitation(leaking) or stenosis(narrowing), or an artificial valve that starts to pull away from the heart tissue In some cases the doctors also insert an ultrasound probe into the esophagus or the food pipe (transesophageal echo), to get a clear and closer image of the heart.

• Checking of the heart valve tissue- this is done to check which kind of microbe is present.

• Positron emission tomography (PET) or nuclear medicine scans to form images using the radioactive material that can show the location of the infection.

How Is Right-Sided Endocarditis Treated?

Right-sided endocarditis once diagnosed by the doctors requires immediate treatment as it can be a fatal condition if left untreated for too long. The treatment protocol that is followed is-

• Antibiotic therapy- It should be started immediately by intravenous means as soon as the type of bacteria causing right-sided endocarditis is diagnosed. In most cases, it is Staphylococcus aureus. Broad-spectrum antibiotics are usually preferred. This helps in reducing inflammation and is continued until signs of improvement are seen. Even after the discharge, antibiotics are continued.

• Refractory surgery- Refractory surgery in cases of right-sided heart failure is also recommended in cases of severe tricuspid regurgitation, and persistent bacteremia (more than seven days) refractory to culture-directed antibiotics and when the vegetation on tricuspid is greater than 20 mm in length.

• Other surgical interventions include vegetation removal, valve repair, and radical debridement of vegetation and infected tissue and valve repair. Surgical techniques can also be categorized into prosthetic- Tricuspid valve replacement and non-prosthetic - bicuspidization.

Conclusion:

This article gives details of right-sided endocarditis, its causes, symptoms, diagnosis, and treatment. Right-sided endocarditis is the inflammation of the outer covering of the heart which involves the tricuspid valve. It is caused mostly by Staphylococcus aureus or due to the use of intravenous injections, catheters or inter cardiac diseases, all of which have been occurring more in the past 20 years.

It accounts for almost 5-10 % of all cases of infective endocarditis. The symptoms of right-sided endocarditis include cough, dyspnea, high persistent fever, etc. The diagnosis can be done by a blood test, culture test, echocardiography, etc. Treatment of right-sided endocarditis is done mostly by starting intravenous antibiotic therapy. Some surgical procedures are also performed for the removal of vegetation.