Acquired Heart Disease

PEDIATRIC CARDIOLOGY

Ruby Ann L. Punongbayan, MD

ACQUIRED HEART DISEASE • Rheumatic heart disease • Infective endocarditis

ACUTE RHEUMATIC FEVER • Immunologic lesion that occurs as a delayed sequela of grp A streptococcal infection of the pharynx but not the skin • Attack rate of post-streptococcal infection 0.3-3% • Predisposing factors: family history of RF, low socioeconomic status (poverty, poor hygiene, medical deprivation), 6-15 years old

RHEUMATIC FEVER • Diffuse inflammatory lesion of connective tissues found mainly in the heart, brain, joints & skin • Valvular damage: mitral valve > aortic valve > tricuspid > pulmonary valve • Aschoff bodies in the atrial myocardium (inflammatory lesions with swelling, fragmentation of collagen fibers, altered staining characteristics of connective tissue)

RHEUMATIC FEVER • History of streptococcal pharyngitis 1-5 weeks before the onset of symptoms • Pallor, malaise, easy fatigability, abdominal pain • Family history of rheumatic fever • Autoimmune or “cross-reactivity” injury between streptococcal antigens & heart protein has been established • Level of auto-antibodies are too low and show little correlation with RF

Jones Criteria (1993) •

Major manifestations: 2. Arthritis (70%) – involves large joints simultaneously or in succession; responds dramatically to salicylates 3. Carditis (50%) – includes some or all of the following in increasing order of severity:

Jones Criteria (1993) a. Tachycardia (out of proportion to the fever) – its absence makes the diagnosis of myocarditis unlikely b. Heart murmur of valvulitis – MR or AR c. Pericarditis – friction rub, pericardial effusion, chest pain, ECG changes d. Cardiomegaly – seen on chest X-ray e. Signs of CHF – gallop rhythm, distant heart sounds, cardiomegaly

Rheumatic Carditis • Valvulitis – murmurs • Myocarditis – unexplained cardiomegaly or CHF or gallop • Pericarditis – friction rub or pericardial effusion • Miscellaneous findings – conduction disturbances in the ECG; 2D echo findings

Jones Criteria (1993) 3. Erythema marginatum (<10%) – nonpruritic serpiginous or annular erythematous evanescent rashes most prominent on the trunk and inner proximal portions of the extremities; never on the face (disappear on exposure to cold and reappear after a hot shower or if covered with a blanket); blanches on pressure

Jones Criteria (1993) 4. Subcutaneous nodules (2-10%) – particularly seen in recurrent cases; hard, painless, nonpruritic, freely movable swellings 0.2-2 cm in diameter; found symmetrically, singly or in clusters on the extensor surfaces of large & small joints, over the scalp or along the spine; last for weeks

Jones Criteria (1993) 5. Sydenham’s chorea (15%) – occurs more often in prepubertal girls; consist of choreic movements (spontaneous purposeless movements followed by motor weakness),hypotonia, emotional lability, hyperactivity, separation anxiety, obsessions & compulsions; may be related to dysfunction of BG & cortical neurons; increased titers of “antineuronal antibodies” in >90%

Jones Criteria (1993) • 2. 3. 4. 5.

Minor manifestations: Arthralgia – not considered a minor manifestation if arthritis is present Fever – at least 38.8 C Elevated acute phase reactants (CRP and ESR) Prolonged PR interval on the ECG

EVIDENCE OF ANTECEDENT GROUP A STREPTOCOCCAL INFECTION 1. History of sore throat/scarlet fever unsubstantiated by lab. data is not adequate evidence of recent infection. 2. A negative rapid strep antigen detection test should be confirmed by a conventional throat culture. 3. Streptococcal antibody tests are the most reliable lab.evidence. The onset of the clinical manifestations coincide with the peak of the streptococcal antibody response.

EVIDENCE OF ANTECEDENT GROUP A STREPTOCOCCAL INFECTION •

• •

Antistreptolysin 0 (ASO) titer is well standardized; elevated in 80% of patients; 333 Todd units in children and 250 Todd units in adults; a single low titer does not exclude RF; a 4-fold rise in titer in 2 samples taken 10 days apart; peaks at 4-6 wks & decreases after another 2 weeks Antideoxyribonuclease B test – 240 Todd units in children & 120 Todd units in adults Streptozyme test – slide agglutination test but less standardized

Diagnosis • Highly probable when either 2 major or 1 major and 2 minor manifestations plus evidence of antecedent streptococcal infection are present • Absence of supporting evidence of a previous group A strep.infection makes the diagnosis doubtful

Diagnosis • Exception to the Jones criteria:  Chorea may occur as the only manifestation of RF  Indolent carditis may be the only manifestation in patients who come to medical attention months after the onset of RF  Occasionally, patients with RF recurrences may not fulfill the Jones criteria.

Diagnosis • The following tips help in applying JC:  Two major manifestations are always stronger than 1 major plus 2 minor.  Arthralgia or a a prolonged PR interval cannot be used as a minor manifestation in the presence of arthritis or carditis respectively.  Absence of evidence of an antecedent grp A strep,infection is a warning that acute RF is unlikely (except when chorea is present).

Diagnosis  Clearly distinguish between Still’s murmur and MR murmur.  The possibility of the early suppression of full clinical manifestation should be sought during the history taking. Subtherapeutic doses of aspirin may suppress full manifestations.

Clinical Course 1. Only carditis can cause permanent cardiac damage. Signs of mild carditis disappear rapidly in weeks but those of severe carditis may last for 2-6 months. 2. Arthritis subsides within a few days to several weeks even without treatment and does not cause permanent damage. 3. Chorea gradually subsides in 6-7 months or longer and usually does not cause permanent neurologic sequelae.

Management • CBC, ESR, CRP, throat culture, ASO titer, chest X-ray, ECG, 2-D echo • Benzathine Penicillin G 0.6-1.2 M units IM to eradicate streptococci; Pen VK 200-500 mg QID for 10 days; Erythromycin 40 mg/kg/day TID for 10 days if allergic to Penicillin • Salicylates and steroids are started if definite diagnosis is made for 6-8 wks.

Management • Prednisone 2mg/kg/day in 4 divided doses for 2-6 weeks indicated only in cases of severe carditis • Mild to moderate carditis – aspirin alone 90100 mg/kg/day in 4-6 doses (adequate blood level is 20-25 mg/100 mL); continued for 4-8 weeks and withdrawn gradually over 4-6 weeks while monitoring ESR and CRP • Arthritis – aspirin is continued for 2 weeks and gradually tapered in 2-3 weeks

RF Prophylaxis • Primary – prevents 1st episode of RF  Treat strep throat infection • Secondary – prevents recurrences  Pen VK 250 mgQID  Benzathine PCN 0.6 – 1.2 M units IM every 21 days  Arthritis – at least 5 years  Carditis – at least 10 years  Recurrence-free & no residual heart disease

RF is considered ACTIVE: • • • • • • • • • •

Joint symptoms New organic murmurs Changing heart size CHF (in the absence of long-standing valvular disease) Subcutaneous nodules Sleeping pulse rate > 100/minute Erythema marginatum Chorea A positive test for CRP Fever for at least 3 consecutive days

RF Recurrences • A recurrent attack refers to a new episode of RF in a patient with previous history, and not a relapse of the first episode • Occur during repeated bouts of GABHS infection, both clinical and subclinical • Importance of secondary prophylaxis • May be more severe • Residual valvular disease a risk factor

Management • Treatment of CHF includes some or all of the ff: complete bed rest and oxygen; morphine 0.2 mg/kg at 4-hr interval for severe CHF with respiratory distress; restriction of sodium and fluid intake; prednisone for severe carditis of recent onset; digoxin; furosemide 1 mg/kg every 6-12 hrs

Management • Sydenham’s chorea: reduce physical & emotional stress; Benzathine Penicillin G 1.2 M units and every 28 days for prevention of recurrence; aspirin not needed in patient with isolated chorea • Presence or absence of permanent cardiac damage determines the prognosis

Recommended Anti-inflammatory Agents Arthritis Mild Mod. Severe Alone Carditis Carditis Carditis Prednisone

0

0

0

2-6 wks

Aspirin

1-2 wks

3-4 wks

6-8 wks

2-4 mos

VALVULAR HEART DISEASE • Congenital or acquired; almost all acquired VHDs are rheumatic in origin • Mitral valve ¾; aortic valve ¼ of cases • Tricuspid valve involvement is rare • Pulmonary valve involvement almost never occurs

Mitral Stenosis • Most common valvular involvement in adults • Thickening of leaflets and fusion of the commissures-calcification with immobility of the valve results • LA and right-sided heart chambers become dilated and hypertrophied • If with pulmonary venous hypertension, pulmonary congestion & edema, fibrosis of alveolar walls, hypertrophy of pulmonary arterioles & loss of lung compliance occurs.

Mitral Stenosis • Asymptomatic if mild • Dyspnea with or without exertion • Orthopnea, nocturnal dyspnea, palpitation in more severe cases • Increased RV impulse along LSB • Weak peripheral pulses with narrow pulse pressure

Mitral Stenosis • Loud S1 at the apex & a narrowly split S2 with loud P2 • Opening snap is followed by a low-frequency mitral diastolic rumble at the apex • CXR: LA & RV enlarged; prominent MPA • Lung fields show pulmonary venous congestion & interstitial edema (Kerley’s B lines)

Mitral Stenosis • Most children are asymptomatic but become symptomatic with exertion • Subacute bacterial endocarditis • Hemoptysis can develop from the rupture of small vessels in the bronchi as a result of long-standing pulmonary venous hypertension

Mitral Stenosis • Good dental hygiene & antibiotic prophylaxis against SBE • Closed mitral commissurotomy for those without calcification • Valve replacement if valves are calcified • Regular checkups for possible dysfunction of the replaced/repaired valve

Mitral Regurgitation • Most common valvular involvement in children with RHD • Shortened leaflets due to fibrosis • Dilated LA & LV with dilated MV ring • Asymptomatic during childhood • Hyperdynamic apical impulse is palpable in severe MR

Mitral Regurgitation • S1 is normal or diminished • S2 may widely split; loud S3 • Hallmark: systolic regurgitant murmur gr 2-4/6 at the apex with transmission to the left axilla • Short, low-frequency diastolic rumble at the apex

Mitral Regurgitation • MS eventually supervenes • Preventive measures against SBE • Afterload-reducing agents to maintain forward cardiac output • Diuretics & digoxin for CHF • MV repair or replacement • Check valve function post-surgery

Aortic Regurgitation • Most patients with AR have associated MV disease • Semilunar cusps are deformed & shortened; dilated valve ring so that the cusps fail to appose tightly • Asymptomatic if mild • Reduced exercise tolerance in severe AR or if with CHF

Aortic Regurgitation • Hyperdynamic precordium; (+)diastolic thrill at the 3rd LICS • Wide pulse pressure and a bounding waterhammer pulse in severe AR • S1 is decreased in intensity; S2 may be normal or single • High-pitched diastolic murmur heard best at the 3rd-4th LICS – hallmark and more easily audible when sitting & leaning forward

Aortic Regurgitation • LVH/LAH in the ECG • CXR: LVE, dilated ascending aorta & prominent aortic knob • Patients deteriorate rapidly if symptoms begin • Anginal pain, CHF, multiple PVCs • Good oral hygiene & antibiotic prophylaxis • ACE inhibitor to reduce the dilatation of LV • Digoxin, diuretics, afterload-reducing agents • AV replacement before irreversible dilatation of LV develops • Follow-up of valve function post-surgery

INFECTIVE ENDOCARDITIS • Etiology: viridans-type streptococci (alpha-hemolytic strep) and Staphylococcus aureus • Other causes: group D strep (enterococcus) (S. bovis, S. faecalis), Strep,pneumoniae, H. influenzae, coagulase (-) staph, Staph epidermidis, Pseudomonas aeruginosa, etc. • ~6% of cases: blood cultures are (-) • Often a complication of congenital or rheumatic heart disease • Can also occur in children without any abnormal valves or cardiac malformations

IE • Developed countries: congenital heart disease is the major predisposing factor (blood is ejected at high velocity through a hole or stenotic orifice) • Rare in infancy but may occur following open heart surgery or associated with a central venous line • Vegetations form at the site of the endocardial or intimal erosion that results from the turbulent flow • At high risk: VSD, AS, TOF, PDA, MVP, children who underwent valve replacement • ~65% of cases: surgical or dental procedure

Clinical Manifestations • Prolonged fever • Fatigue, myalgia, arthralgia, chills, headache, nausea, vomiting • New of changing heart murmur • Splenomegaly, petechiae • Embolic stroke, cerebral abscess, mycotic aneurysm, hemorrhage • Meningismus, increased ICP, altered sensorium, focal neurologic signs

Clinical Manifestations • Osler nodes – tender, pea-sized intradermal nodules in the pads of fingers & toes • Janeway lesions – painless small erythematous or hemorrhagic lesions on the palms & soles • Splinter hemorrhages – linear lesions beneath the nails • Identification of IE is most often based on a high index of suspicion during evaluation of an infection in a child with an underlying contributory factor

Diagnosis • Blood culture (3-5 separate blood collections; causative agent recovered in 90% of cases) • Antimicrobial pretreatment reduces the yield of blood culture to 50-60% • TEE cardiography, 2D echo, Doppler (>1 cm lesions and fungating masses are at greatest risk for embolization) • Absence of vegetations does not exclude endocarditis

Duke Criteria •

Major criteria

 

(+) blood culture (2) Evidence of endocarditis on echocardiography: Intracardiac mass on a valve or other site Regurgitant flow near a prosthesis Abscess Partial dehiscence of prosthetic valves New valve regurgitant flow

4. 5. 6. 7. 8.

Duke Criteria •

Minor criteria

2. 3. 4. 5.

Predisposing conditions Fever Embolic-vascular signs Immune complex phenomena (GN, arthritis, rheumatoid factor, Osler nodes, Roth spots) A single (+) blood culture or serologic evidence of infection Echocardiographic signs not meeting the major criteria

6. 7.

Duke Criteria 7. Presence of newly diagnosed clubbing 8. Splenomegaly 9. Splinter hemorrhages 10. Petechiae 11. High ESR 12. High CRP 13. Presence of central nonfeeding lines 14. Peripheral lines 15. Microscopic hematuria

How to use the Duke criteria •

Definite endocarditis 2. 2 major criteria 3. One major and 3 minor 4. 5 minor criteria

Prognosis & Complications • Despite the use of antibiotic agents, mortality remains at 20-25% • Serious morbidity occurs in 50-60% of children with documented IE (heart failure due to aortic or mitral valve vegetations) • Myocardial abscesses • Systemic or pulmonary emboli • Mycotic aneurysms • Heart block

Treatment • Several weeks are required for a vegetation to organize completely  therapy must be continued through this period to avoid recrudescence • Total of 4-6 weeks is recommended • Nonstaphylococcal disease: fever resolves in 5-6 days with antibiotics • Surgery for severe aortic or mitral valve involvement with intractable heart failure, myocardial abscess, recurrent emboli, new heart block, increasing size of vegetations while receiving therapy

Treatment • Staphylococcus: Oxacillin with optional addition of Gentamicin; if resistant – Vancomycin • Streptococcus: Penicillin G Na or Ceftriaxone plus Gentamicin • Prosthetic valve endocarditis due to Staph: Oxacillin + Rifampicin + Gentamicin