INFECTIOUS ENDOCARDITIS
Infective endocarditis is a form of endocarditis caused by infectious agents. Agents are usually bacteria, but other agencies may also be responsible. Heart valves do not receive the blood supply is engaged. Consequently, immune defense mechanisms (such as white blood cells) can not directly reach the valve through the bloodstream. If an organism (like bacteria) binds to a valve surface and forms of vegetation, the host immune response is blunted. The lack of blood supply to the valve also has implications for treatment, because medicines are also difficult to reach the infected valve. Normally, blood flows smoothly through these valves. If damaged - rheumatic fever, for example - the risk of bacterial adhesion is higher.
Infective endocarditis (IE) is an infection of the endocardial surface of the heart. The impact of this infection include severe valvular regurgitation intracardiac, which can lead to intractable congestive heart failure and myocardial abscesses. IE also produces a wide variety of systemic signs and symptoms through several mechanisms, including both sterile and infected emboli and various immunological phenomena.
PATHOPHYSIOLOGY
Though uncertain, it is believed that the heart valve of infective endocarditis and other surfaces of heart when exposed to bacteria or fungi microemboli moves into the bloodstream. Dextran-producing bacteria for example Streptococcus mutans, a virulence factor in promoting compliance with the endovascular surfaces. Coagulase-negative staphylococci to produce biofilm is a prosthetic surface, which also contribute to a commitment. beta-hemolytic streptococci and enteric gram-negative bacteria is recognized factors such as respect, and seems less likely to cause blood poisoning. Endocardial surface is already damaged heart valve disease, endocarditis, surgery, or pacemaker wires create a favorable environment for the formation of thrombi. Over time, microorganisms multiply in whirlwinds, which is a classic vegetation. Micro-organisms to be put into circulation, usually continuously, which often leads to interesting results.
The infection of the heart valve relatively resist by normal structure. Bacteria and fungi are not easy to attach to the endocardial surface, and constant good blood supply can prevent it from depositing in the structures of the endocardium. Thus, two factors generally required for infective endocarditis: predisposing alteration of the endocardium and microorganisms in the bloodstream (bacteremia). In a rare cases , bacteremia or mass of microorganisms specifically virulent cause of endocarditis on normal valves of the heart.
Endocarditis commonly involves the cardiac valves. The main predisposing factors are congenital heart defects, rheumatic valve disease, bicuspid or calcific aortic, mitral valve prolapse and hypertrophic cardiomyopathy. artificial valves are at particular risk. Sometimes, the sites of mural thrombus, ventricular septal defects and patent ductus arteriosus will be infected. The actual nidus of infection is usually a sterile fibrin-platelet vegetation ,it can formed when tissue factor release by damaged endothelial cells.
Infective endocarditis is a form of endocarditis caused by infectious agents. Agents are usually bacteria, but other agencies may also be responsible. Heart valves do not receive the blood supply is engaged. Consequently, immune defense mechanisms (such as white blood cells) can not directly reach the valve through the bloodstream. If an organism (like bacteria) binds to a valve surface and forms of vegetation, the host immune response is blunted. The lack of blood supply to the valve also has implications for treatment, because medicines are also difficult to reach the infected valve. Normally, blood flows smoothly through these valves. If damaged - rheumatic fever, for example - the risk of bacterial adhesion is higher.
Infective endocarditis (IE) is an infection of the endocardial surface of the heart. The impact of this infection include severe valvular regurgitation intracardiac, which can lead to intractable congestive heart failure and myocardial abscesses. IE also produces a wide variety of systemic signs and symptoms through several mechanisms, including both sterile and infected emboli and various immunological phenomena.
There are several ways to classify endocarditis. The simplest classification is based on the causes of this disease , whether infected or not the infection, depending on whether the organism causes inflammation. Regardless, the diagnosis of endocarditis on the basis of clinical features, investigations such as cardiac ultrasound, as well as all blood cultures demonstrated the presence of micro-organisms that cause endocarditis.
PATHOPHYSIOLOGY
Though uncertain, it is believed that the heart valve of infective endocarditis and other surfaces of heart when exposed to bacteria or fungi microemboli moves into the bloodstream. Dextran-producing bacteria for example Streptococcus mutans, a virulence factor in promoting compliance with the endovascular surfaces. Coagulase-negative staphylococci to produce biofilm is a prosthetic surface, which also contribute to a commitment. beta-hemolytic streptococci and enteric gram-negative bacteria is recognized factors such as respect, and seems less likely to cause blood poisoning. Endocardial surface is already damaged heart valve disease, endocarditis, surgery, or pacemaker wires create a favorable environment for the formation of thrombi. Over time, microorganisms multiply in whirlwinds, which is a classic vegetation. Micro-organisms to be put into circulation, usually continuously, which often leads to interesting results.
CAUSES
The infection of the heart valve relatively resist by normal structure. Bacteria and fungi are not easy to attach to the endocardial surface, and constant good blood supply can prevent it from depositing in the structures of the endocardium. Thus, two factors generally required for infective endocarditis: predisposing alteration of the endocardium and microorganisms in the bloodstream (bacteremia). In a rare cases , bacteremia or mass of microorganisms specifically virulent cause of endocarditis on normal valves of the heart.
Endocarditis commonly involves the cardiac valves. The main predisposing factors are congenital heart defects, rheumatic valve disease, bicuspid or calcific aortic, mitral valve prolapse and hypertrophic cardiomyopathy. artificial valves are at particular risk. Sometimes, the sites of mural thrombus, ventricular septal defects and patent ductus arteriosus will be infected. The actual nidus of infection is usually a sterile fibrin-platelet vegetation ,it can formed when tissue factor release by damaged endothelial cells.
The microorganisms that infect the some layer of heart ( endocardium ) can originate from distant infected sites (example, skin abscesses, inflammation or infection of the gums, urinary tract infection) or visible portals of entry like in a central venous catheter or an injection site . Almost all the foreign material implanted (eg, ventricular peritoneal implants) runs the risk of bacterial colonization, thereby becoming a source of infection and therefore endocarditis. Infective Endocarditis can also be asymptomatic bacteremia, as occurs during invasive dental procedures, medical or surgical procedures. Even brushing your teeth, chewing, can cause septicemia (usually due to Streptococcus viridans) in gingivitis patients........ read more
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