WHAT IS RHEUMATIC HEART DISEASE
Rheumatic heart disease is a chronic inflammatory process of the membrane surrounding the heart due to rheumatic fever. This fever mainly affects children and young adults, resulting in delayed complications of upper respiratory tract infection with hemolytic streptococci.
Death rarely occurs in the acute phase, despite retrieval there may be permanent damage to the heart valves, eventually leading to disability and possibly cardiac failure.
SIGNS AND SYMPTOMS OF RHEUMATIC HEART DISEASE
1 – RHEUMATIC FEVER
- Fever
- Painful joints ( migrating pain from joint to joint )
- Red, warm, swollen joints
- Small, painless bumps beneath the skin
- Chest pain
- Heart murmur
- Painless rash with a jagged edge ( erythema marginatum )
- Jerky movement
- Unusual behavior accompanying the movement
2 – HEART VALVE PROBLEM
- Chest discomfort or pain
- Irregular or rapid heartbeat (heart pulse)
- Shortness of breath
- Fatigue or weakness
- Light-headedness, dizziness, or near fainting
- Swelling of the stomach, feet, or ankle
Read more: THE HEART: ANATOMY, STRUCTURE, AND BLOOD SUPPLY
RISK FACTORS
Risk factors are poverty and overcrowded housing in the drier areas of the tropics. This is presumably due to easier transmission or acquisition of streptococcus pyogenes in a hot dry climate. WHO has used, as a baseline for further studies, a mean prevalence of 10/1000 for established rheumatic heart disease and an incidence of rheumatic fever of 100/100 000, but methods of study vary greatly.
CRITERIA FOR DIAGNOSIS
The Duckett Jones criteria have been successively modified because chorea, subcutaneous nodules, and erythema marginatum are rare in the topics: carditis is allowed as the only major manifestation, and arthralgia instead of arthritis. Rheumatic fever follows infection with streptococcal pyogenes. For every 100 cases of sore throat, 20 are caused by strep. pyogenes. For every 100 of these caused by strep. pyogenes, 20 are symptomatic with fever and cervical lymph nodes. Out of these 20 symptomatic cases, two of rheumatic fever may develop, whereas only one cause may develop in the 80 without symptoms, except during an epidemic, when the numbers are increased five times.
CLINICAL FEATURES
Echocardiography is important for confirming a diagnosis and for following the evolution of the disease.
Rheumatic fever
Carditis in a child may present as a low-grade fever tachycardia and nothing else. Dissociation between the height of the temperature and the tachycardia, and a cardiac murmur- systolic or diastolic- at the apex of the heart may help in diagnosis.
Rheumatic heart disease
Established disease affects
- The mitral valve alone leads to mitral incompetence The most common lesions; are mitral stenosis or mixed stenosis and incompetence
- Both mitral and aortic valves
- At least commonly, the aortic valve alone
Streptococcal sore throat
A clinical episode may precede some cases of acute rheumatic fever, and it must be recognized in the community if primary prevention is to have any hope of success. The distinction between a streptococcal and a viral infection may be difficult
Subclinical rheumatic heart disease
Valvular incompetence developing in older people who have a history of rheumatic fever many years previously is believed to be due to repeated subclinical attacks. These attacks are not associated with repeated episodes of sore throat, so it is assumed that the original disease has remained active in a subclinical form. In some cases, there is no history of rheumatic fever.
EFFECTS ORGANS ASSOCIATED WITH THE HEART
1 – EFFECTS ON THE ENDOCARDIUM
The endocardium becomes inflamed and oedematous, and tiny pale areas called Aschoff’s bodies appear when they heal, leaving thick fibrous tissue. Thrombotic fibrous nodules consist of platelets and fibrin form on the heart valves’ free borders of the cusps. When healing occurs, the fibrous tissue formed shrinks as it ages, distorting the shape of the thresholds and causing stenosis and incompetence of the valve.
The left atrioventricular (mitral) and aortic valves are commonly affected, the right- atrioventricular (tricuspid) valve sometimes, and the pulmonary valve rarely.
2 – EFFECTS ON THE MYOCARDIUM
Aschoff’s bodies form on the connective tissue between the cardiac muscle fibers. As in the endocardium, healing is accompanied by fibrosis that may interfere with myocardial contraction.
3 – EFFECTS ON THE PERICARDIUM
Inflammation leads to the accumulation of exudate in the pericardial cavity. Healing is accompanied by fibrous thickening of the pericardium, and adhesions form between two layers. In severe cases, the layers may fuse, obliterating the cavity. Within this inelastic pericardium, the heart may not be able to expand fully during diastole, leading to reduced cardiac output, generalized venous congestion, and edema.
PREVENTION OF RHEUMATIC HEART DISEASE
The fundamental aims are as follows:
1. Environment: To improve homes and housing, food, and health care
2. Primary prevention: To detect and treat symptomatic strep. pyogenes sore throat- with either benzathine penicillin 1.2 megaunits, penicillin v for 10 days, or benzylpenicillin.
3. Secondary prevention: To prevent streptococcal infection, benzathine penicillin every 3 weeks, in those with known rheumatic heart disease, through dedicated community nurses.
TREATMENTS/MANAGEMENT
Acute rheumatic fever
- Most of the patients are currently being treated on an outpatient basis.
- Bed rest is advisable for the patient presenting with carditis (for 4 weeks or at least during the symptomatic stage)
- Antimicrobial therapy for the eradication of pharyngeal streptococcal infection is mandatory. A single dose of benzathine penicillin is ideal. Other agents can also be used.
- Once the ARF manifests, the treatment algorithm varies, depending on the major manifestation.
Chronic rheumatic heart disease
Maintain penicillin prophylaxis to prevent recurrences (and infective endocarditis), and give standard treatment for valvular disease, disorders of rhythm, or cardiac failure.