Endocarditis

A serial ECG may show evidence of pericarditis. There will often be classic upward concave elevations of the ST segment, which are seen in Figure 8:

Figure 8.

In looking for a cause of the pericarditis, it is not necessary to do much in a healthy young person who likely has idiopathic or viral disease. Other testing done if necessary include a diagnostic pericardiocentesis or a pericardial biopsy, looking for things like tuberculosis, cancer, or bacterial infection. Besides a culture and cytology of the fluid, other tests of the fluid are nonspecific and not helpful in making the diagnosis. There are blood tests for autoimmune disease, acute-phase reactants, HIV disease, viral antibodies, and a CBC that can be done.

When treating these patients, those with severe features need hospitalization. Stop all possible causative drugs and do a pericardiocentesis if this is causing symptoms. A pericardiocentesis without an echocardiogram to guide the procedure can be lethal so it should wait until it can be done under guidance. Colchicine or aspirin can be used for pain and prednisone for a week will help if the colchicine or aspirin do not help. In refractory disease, triamcinolone can be injected into the pericardial space. Severe constrictive pericarditis is treated surgically with resection of the pericardial sac but the mortality rate of the procedure itself is high.

ENDOCARDITIS

Endocarditis can be due to several things but most are infectious and most infections are due to staph or strep infections. Fungal infections can also cause this problem. Expect to see fever, petechiae, heart murmurs, embolic diseases, anemia, and an imaging study showing endocardial vegetations on the heart valves. In noninfective

cases, there will be platelets and fibrin strands on the valves, but these will be sterile. The diagnosis is mostly clinical but can be confirmed with imaging.

Predisposing factors to developing this problem include heart valve diseases, hypertrophic cardiomyopathy, or prior endocarditis. Those with structural congenital heart diseases have an increased risk of endocarditis as well. The organisms involves usually come from distant sites, such as the mouth, cutaneous abscesses, or known portals of entry through the skin. Pacemakers and shunts can also be sources of infection. Most infections are from staph or strep but other bacteria and fungi can cause this problem.

The three stages of the infection are bacteremia, adhesion of organisms, and colonization of the adherent organisms. Many species make biofilms that protect them from host immune defenses and antibiotic therapy. The local effects include myocardial abscess formation, aortitis, and sudden valvular regurgitation leading to death. Systemic complications include all types of infectious emboli and activation of the immune system in chronic disease states.

The symptoms may vary by type of endocarditis. In subacute bacterial endocarditis, the patient will have a fever, fatigue, night sweats, weight loss, and malaise. Almost all patients will have a murmur eventually. Look for evidence of emboli to the retina, conjunctivae, skin, kidneys, or CNS. If the disease is acute, the patient will have similar symptoms but a more rapid course and the presence of toxic shock in some settings. Right-sided disease will lead to pulmonary emboli, with symptoms of cough, chest pain, and hemoptysis.

The diagnosis is largely clinical and involves insidious symptoms but, if things like a murmur are present, this will help to make the diagnosis. Blood cultures might identify the organism but a negative culture does not rule out the disease process. Echocardiography will often show the vegetations on the heart valves. Those with a fever who are not taking antibiotics will have a high rate of positive blood cultures, although some may need repeated cultures to get a positive one. A transesophageal echocardiogram is the best test for this but a CT scan will better show abscesses near the valves.

Infectious endocarditis needs to be treated because it is fatal if not treated. IV antibiotics over a long course is recommended, although some patients will need valvular debridement, valve repair, or valve replacement. All patients need to be examined for a source of infection, particularly a dental source and those who have catheters or devices as causes of infection need to have these removed.

The patient who is high risk for endocarditis should have prevention of this problem. If the person is having heart valve surgery, they need preventive tooth extractions, enhanced dental hygiene, and enhanced cutaneous hygiene. Antimicrobial prophylaxis is recommended for those with prosthetic heart valves, heart transplants, or congenital heart disease. Dental procedures that involve the gingiva, respiratory tract procedures, and vaginal deliveries are all indications for prophylaxis, while known surgery involving an established infections also require prophylaxis against staph and strep infections.