Endocarditis

Definition/Etiology:

Endocarditis occurs when a patient has bacteria in the blood that begin to stick to a heart valve (vegetate).

Risk factors include: male, >60 years old, injection drug use, and poor dentition.

Common comorbid conditions include: indwelling medical device, prosthetic heart valve, congenital heart disease, and hemodialysis.

Top four pathogens are: Staph aureus, Viridians group streptococci, Enterococci, and Coagulase-negative staphylococci.

Pathophysiology:

Some bacteria have sticky coatings and adhere to heart valves. Valves should open and close fully and easily; however, when they don’t, because of damage or calcification, then turbulent blood flow occurs. This turbulence creates an area where bacteria can begin to stick to the heart valve. Rheumatic, stenotic, prolapsing, prosthetic, or regurgitant valves are at risk, as well as valves with a prior history of endocarditis.

Clinical Presentation:

• Fever is present in ~90% of patients
• Janeway lesions: red or dark spots on palms/soles
• Osler nodes: tender nodules on the pads of the fingers
• Petechiae
• New cardiac murmur
• Septic emboli can cause multi-organ failure, septic arthritis, and stroke
• Heart failure due to valve damage
• New heart blocks due to infection entering the heart muscle and conduction system.

Collaborative Management:

• Blood cultures from 2 sites prior to empiric antibiotic treatment.
• Transthoracic echocardiogram to look for vegetation on valves, and paravalvular abscess. If negative, or if a better view is needed, can do transesophageal echocardiogram.
• CXR to look for septic pulmonary emboli, infiltrates (with or without cavitation), congestive heart failure, and potential alternative causes of fever and systemic symptoms.
• CT chest/abdomen/pelvis to look for metastatic infection.
• Dental evaluation.
• Typical IV antibiotic treatment is 4-6 weeks in duration.

Evaluation | Patient Monitoring | Education:

• Monitor for septic emboli
• Monitor for new murmurs
• Teach patient the signs and symptoms of heart failure
• If patient injects drugs and wants to quit, refer to social worker to coordinate a drug treatment counseling program

Linchpins: (Key Points)

• Infective endocarditis should be suspected in febrile patients with risk factors and common comorbid conditions.
• Delay in diagnosis and treatment may be associated with complications, including valvular regurgitation, heart failure (HF), embolic events, and sepsis.
• A damaged or dysfunctional valve is at risk for endocarditis due to turbulent flow.
• Skin lesions and murmurs can indicate a much larger problem.