Rheumatic Heart Disease: Diagnosis, Emergency Management of Carditis, and Follow-up

1. Diagnostic Criteria — Revised Jones Criteria (AHA, 2015)

Major criteria

Minor criteria

Evidence of preceding GAS infection (any one)

• Elevated or rising anti-streptolysin O (ASO) or anti-DNase B titer
• Positive throat culture for GAS
• Positive rapid streptococcal antigen test in a child whose clinical presentation supports ARF

Definition of carditis in the 2015 criteria

• Clinical carditis: pathological mitral and/or aortic regurgitant murmur, pericarditis/pericardial rub or effusion, or new heart failure without other explanation.
• Subclinical carditis: echocardiographic evidence of valvulitis (pathological mitral or aortic regurgitation by Doppler criteria) in the absence of a murmur. Echocardiography is now recommended in all patients with suspected or confirmed ARF, even if no murmur is audible - this is the major change from earlier Jones criteria (Braunwald's Heart Disease, p. 1535-1536; Firestein & Kelley's Textbook of Rheumatology).

Diagnosis of established chronic RHD

2. Emergency Management of a 6-Year-Old with Rheumatic Carditis

Step 1: Triage and stabilization (ABCs)

• Assess airway, breathing, circulation immediately - carditis can present with acute heart failure (tachypnea, tachycardia, hepatomegaly, gallop rhythm, basal crepitations, poor feeding, edema).
• If in overt CHF or cardiogenic shock: give oxygen, position semi-upright, secure IV access, continuous cardiac monitoring and pulse oximetry.
• Admit all children with suspected/confirmed carditis - outpatient management is not appropriate for acute carditis.

Step 2: Confirm the diagnosis while stabilizing

• 12-lead ECG (look for PR prolongation, arrhythmia)
• Echocardiogram (assess valvulitis - mitral/aortic regurgitation, ventricular function, pericardial effusion, chamber size)
• Baseline bloods: CBC, ESR, CRP, throat swab/rapid antigen test, ASO/anti-DNase B titers, blood culture if endocarditis is a differential, chest X-ray (cardiomegaly, pulmonary edema)

Step 3: Treat heart failure if present

• Diuretics (furosemide) for volume overload
• ACE inhibitors for afterload reduction in significant mitral/aortic regurgitation
• Digoxin can be used cautiously for rate control/inotropy, but use lower doses and monitor closely since myocarditis increases digoxin sensitivity
• Fluid and salt restriction as needed
• Bed rest: activity should be restricted according to symptoms (arthritis, chorea, or heart failure). Strict prolonged bed rest for asymptomatic carditis has no proven benefit; ambulation resumes once fever settles and acute-phase reactants trend down (Braunwald's Heart Disease, p. 1537-1538).

Step 4: Eradicate the streptococcal infection

• A single dose of IM benzathine penicillin G (600,000 U for <27 kg, 1.2 million U for ≥27 kg) - this simultaneously treats the current GAS infection and starts the secondary prophylaxis schedule.
• Alternative: 10-day course of oral penicillin V or amoxicillin, or erythromycin/azithromycin if penicillin-allergic.

Step 5: Anti-inflammatory therapy

• Aspirin is the traditional first-line anti-inflammatory agent for arthritis/arthralgia and mild carditis: 80-100 mg/kg/day in 4 divided doses, tapered over 4-6 weeks as ESR/CRP normalize. Monitor for salicylate toxicity and hepatotoxicity.
• Corticosteroids (oral prednisolone, 1-2 mg/kg/day) are reserved for moderate-to-severe carditis or carditis with heart failure - though evidence from Cochrane reviews and meta-analyses shows steroids have not been definitively proven to alter long-term valve outcomes, they remain widely used clinically to control acute inflammation, and are tapered over 2-3 weeks with aspirin overlap during the taper to prevent rebound inflammation.
• No specific anti-inflammatory therapy has been shown to change the natural history/long-term valve damage of carditis - the goal is symptom control (Firestein & Kelley's Textbook of Rheumatology; Cochrane review by Cilliers et al.).

Step 6: Treat chorea/arthritis if coexisting

• Chorea: minimize stimulation, consider carbamazepine or valproate if severe/disabling; carditis workup (echo) is mandatory even in isolated chorea since subclinical carditis is common.

Step 7: Initiate secondary prophylaxis

3. Follow-up Plan

Secondary antibiotic prophylaxis (the cornerstone of preventing progression to chronic RHD)

• Benzathine penicillin G IM every 3-4 weeks (some high-risk areas use every 3 weeks because levels can fall below protective threshold at 4 weeks). Dose: 600,000 U if <27 kg, 1.2 million U if ≥27 kg.
• Alternative if penicillin allergic: oral erythromycin or sulfadiazine daily.
• Duration depends on carditis severity:
  • No carditis: minimum 5 years or until age 21, whichever is longer
  • Carditis that resolved (no residual valve disease): 10 years or until age 21, whichever is longer
  • Persistent valve disease (mild): 10 years or until age 25 (or later), whichever is longer
  • Severe valve disease/post-valve surgery: lifelong prophylaxis

Clinical and echocardiographic follow-up

• Regular clinic visits: monthly initially, then every 3-6 months
• Repeat echocardiography to track valve status - at least annually, more frequently if carditis was moderate-severe or if there is ongoing ventricular dysfunction
• Monitor growth, development, and school/activity tolerance
• ECG at follow-up visits if PR prolongation or arrhythmia was noted acutely

Prevention of recurrence

• Strict adherence counseling for the family - recurrence risk after another untreated GAS pharyngitis is roughly 50% in a sensitized child, and each recurrence worsens valve damage
• Educate family to seek care promptly for any sore throat and to never miss the penicillin injection schedule
• Screen and treat symptomatic household contacts for GAS pharyngitis

Longer-term issues to plan for

• Infective endocarditis prophylaxis counseling before dental/invasive procedures if significant residual valve disease
• Watch for progressive valve stenosis/regurgitation over years - refer to pediatric cardiology for consideration of balloon valvotomy or valve surgery if severe stenosis/regurgitation develops
• Transition planning to adult rheumatology/cardiology services as the child grows, with continued prophylaxis compliance emphasized through adolescence
• Vaccination and general health maintenance should continue on schedule

A brief evidence note