Bacterial endocarditis is a rapidly...

Bacterial endocarditis is a rapidly progressive bacterial infection of the lining of the endocardium or heart valves, which is characterized by means of vegetative growths and the spread of pathogenic microorganisms via the kin stream to other organs or tissues (eg megrims kidneys, central nervous system, lungs)(1) Bacterial endocarditis, if not diagnosed early and treated aggressively with antibiotics, usually is fatal; however, 70% of patients cure if they receive proper treatment. Patients' prognoses are poor when bacterial endocarditis causes strait-laced damage to the aortic, mitral, or tricuspid valves that leads to cardiac insufficiency and congestive heart failure. Preexisting rheumatic heart lesions are a frequent predisposing factor to the progression in a continuously ascending gradation of bacterial endocarditis.(2) There are couple types of bacterial endocarditis: acute bacterial endocarditis and subacute bacterial endocarditis. Acute bacterial endocorditis. Acute bacterial endocarditis usually is caused at bacteria present in the progeny after open heart surgery for prosthetic valve placement; septic thrombophlebitis; or skin, bone or lung infections.(3) It is a rapidly progressive bacterial infection that sharply damages the endocardium early in the disease proces Acute bacterial endocarditis is caused by the agency of highly pathogenic microorganisms such as Staphylococcus aureus, pneumococci, dispose A nonhemolytic streptococcus (ie, rheumatic endocarditis), beta-hemolytic streptococci, and gonococci. This form of bacterial endocarditis also be founds in IV drug abusers secondary to the invasion of Staphylococcus aureus, Pseudomonas, or Candida microorganisms.(4) Signs and symptoms of acute bacterial endocarditis include high flush heart murmurs, embolic phenomena, and splenomegaly.(5)

Subacute bacterial endocorditis.

Subacute bacterial endocarditis has an insidious storming and the course of the disease is extended It typically occurs in patients with acquired valvular or congenital heart lesions, on the contrary it may occur in patients after dental, genitourinary, gynecologic, and gastrointestinal surgical procedures(6) The most numerous common causative microorganisms are Streptococcus viridans, Streptococcus faecalis, and Staphylococcus aureus, which normally are indigenous to the corpse (eg, Streptococcus viridans inhabits the upper respiratory tract; Streptococcus faecalis is plant in the gastrointestinal tract, perineal flora; Staphylococcus aureus inhabits the skin). If these microorganisms cause subacute bacterial endocarditis, usually there is little damage to the heart, if patients are treated promptly(7) Signs and symptoms of subacute bacterial endocarditis include a continue lengthen in timeed fever, weight loss, fatigue, joint pain, and splenomegaly.(8) Patients with rigid valvular damage from subacute bacterial endocarditis ofttimes require aortic valve replacement surgery to correct aortic regurgitation and to obviate heart failure.(9)

VALVE REPLACEMENT OPTIONS

There are four different models of aortic valve replacement manner of proceedings that can be used depending forward the patient's age, lifestyle, health, and life expectancy. These aortic valve replacement options include using a

* biologic tissue valve (eg porcine, bovine),

* mechanical valve,

* homograft (ie, cryopreserv human valve), or

* autograft (ie, the patient's confess valve).

Advantages and disadvantages of valvular options. The advantage of biologic valves is that patients do not ne to go through long-term anticoagulation therapy. The disadvantage is that 50% of these patients experience prosthetic complications and require repeat valvular replacement surgery after 10 years. Mechanical valves are superior for patients who have life expectancies that exce 10 years; however, these patients require continuous anticoagulation therapy by the agency of the daily administration of warfarin sodium.

Cryopreserv homografts are an increasingly popular choice for younger patients because there is a cheap risk for emboli and long-term anticoagulation therapy is unnecessary. In addition, solitary 10% of these patients experience prosthetic complications that require repeat valvular replacement surgery after 10 years. Autografts are the superior choice for younger patients for three reasons: native tissue is used, there is no ne for anticoagulation therapy, and barely 15% of these patients require repeat valvular replacement surgery after 20 years.(10)

Native pulmonary valves. A native pulmonary valve placed onward the left side of the heart functions like a natural aortic valve and can withstand the cardiac constraining forces necessary to close the pulmonary cusps better than other prosthetic valves. A native pulmonary valve supports the heart's natural life-current flow because it is les massive than other prosthetic valves, which have large sewing rings attached to them. Native pulmonary valves also have the ability to advance which is very important for young children.(11)

THE ROS PROCEDURE

The Ros practice is a complicated, autograft/homograft surgical course that offers long-term relief for patients who have acutely infected aortic valves. Surgeon replace diseased aortic valves with patients' acknowledge pulmonary valves (ie, pulmonary autografts) and then replace patients' pulmonary valves with cryopreserv valves (ie, pulmonary homografts) (Figures 1 2 and 3) This performance is indicated for young patients who have prolonged life expectancies and isolated aortic valve disease that does not cause unusual aortic cause enlargements. The Ross procedure is not indicated for patients with dissecting aortas, Marfan's syndrome or other diseases that cause aortic lower part enlargement.(12)