Can a patient with rheumatic heart disease experience infective endocarditis?

Can Patients with Rheumatic Heart Disease Experience Infective Endocarditis?

Yes, patients with rheumatic heart disease can absolutely develop infective endocarditis, and historically this has been a well-recognized association, though the epidemiological landscape has shifted in developed nations.

Epidemiological Evidence

The relationship between rheumatic heart disease (RHD) and infective endocarditis (IE) is well-established but varies significantly by geography:

• In developing countries, RHD remains a predominant predisposing factor for IE, with most cases developing in patients with rheumatic valve disease 1
• In industrialized nations, the epidemiological profile has changed substantially since the 1970s, with RHD becoming less common as an underlying condition for IE 1
• A systematic review from seven developed countries showed a decrease in IE cases with underlying rheumatic heart disease over recent decades, replaced by prosthetic valves, degenerative valve disease, and healthcare-associated factors 1

Clinical Evidence from Real-World Practice

Direct evidence confirms that RHD patients do develop IE:

• In a New Zealand study, 22 of 155 IE patients had RHD, presenting at a mean age of 45 years (19 years younger than non-RHD patients) 2
• These RHD patients had significantly higher rates of previous IE (27% vs 5%) and prosthetic valve endocarditis (77% vs 29%) 2
• A British study found that 65% of 40 consecutive IE patients had prior rheumatic heart disease 3
• IE-related mortality was significantly higher in RHD patients (32%) compared to non-RHD patients, with deaths almost exclusively from IE complications 2

Mechanism and Risk Factors

Why RHD predisposes to IE:

• Rheumatic fever causes valvular damage through a pancarditis involving the endocardium, creating structurally abnormal valves that are susceptible to bacterial colonization 1
• The damaged, scarred valvular tissue provides an ideal nidus for bacterial adherence during transient bacteremia 1
• Patients with RHD and prosthetic valves face compounded risk, as both conditions independently increase IE susceptibility 2

Important Clinical Pitfall

A critical diagnostic challenge exists: Acute rheumatic fever and IE can present simultaneously or be difficult to distinguish, as both can occur after streptococcal infection and both can cause valvulitis 4, 5. Cases have been reported where patients met both Jones criteria (for acute rheumatic fever) and modified Duke criteria (for IE) simultaneously 5. This diagnostic overlap requires careful clinical judgment, often necessitating transesophageal echocardiography and sometimes pathological confirmation 4, 5.

Current Prophylaxis Recommendations

The approach to IE prophylaxis in RHD has dramatically changed:

• The 2006 ACC/AHA guidelines previously recommended IE prophylaxis for all patients with acquired valvular dysfunction including rheumatic heart disease (Class I recommendation) 1
• The 2008 updated guidelines removed routine prophylaxis for RHD patients, now only recommending prophylaxis (Class IIa) for those at highest risk for adverse outcomes: patients with prosthetic valves, previous IE, or cardiac transplant with valvulopathy 1, 6
• This change reflects lack of published evidence supporting prophylaxis efficacy in all RHD patients 6
• However, clinicians may still consider prophylaxis in select RHD cases after discussing risks and benefits with patients 1

Key Clinical Considerations

For patients already on rheumatic fever prophylaxis:

• If a patient with RHD is receiving penicillin for secondary prevention of rheumatic fever and requires dental procedure prophylaxis, use an agent other than penicillin due to likely oral streptococcal resistance 6
• Continue benzathine penicillin G (1.2 million units IM every 4 weeks) for rheumatic fever prevention, which is distinct from IE prophylaxis 6

Maintain high clinical suspicion: Healthcare providers should have a low threshold for suspecting IE in RHD patients presenting with fever, new murmur, or systemic symptoms, given their younger age at presentation and higher complication rates 2.