Small Perimembraous Ventricular Septal Defect with Left Ventricular to Right Atrial Shunt Complicate - PowerPoint PPT Presentation

Title: Small Perimembraous Ventricular Septal Defect with Left Ventricular to Right Atrial Shunt Complicate


1
Small Perimembraous Ventricular Septal Defect
with Left Ventricular to Right Atrial Shunt
Complicated by Tricuspid Valve Bacterial
Endocarditis with Enterococcus
Georgios A. Hartas MD, Monesha Gupta-Malhotra MD,
P. Syamasundar Rao, MD Department of Pediatrics,
University of Texas-Medical School at Houston,
Texas
CASE REPORT
DISCUSSION
ABSTRACT
On examination he was in moderate respiratory
distress, with sinus tachycardia, moderate degree
of hepatosplenomegaly, petechiae. The cardiac
examination demonstrated a hyperdynamic
precordium and a thrill in the left lower sternal
border. The heart sounds were slightly muffled.
There was a grade 3/6 blowing HSM, heard best at
left lower sternal border. The remainder of the
physical examination was unremarkable. Laboratory
investigations demonstrated a white blood cell
count of 10.6 x 109/L (3 bands), and a
microcytic anemia (hemoglobin 8.2 g/L). The
platelets were low at 54K. The C-reactive
protein was 6 mg/L. Urinalysis revealed 25 to 30
RBC's. The d-dimer was elevated and the protein C
and AT III level was decreased. The chest x-ray
showed cardiomegaly and small size right pleural
effusion (figure 1). An EKG in the emergency room
was significant for a sinus tachycardia (figure
2). The echocardiogram showed a small
membranous ventricular septal defect with
restrictive flow in addition to a small to
moderate left ventricular to right atrial shunt.
The was significant right atrial and ventricular
dilatation with complete non-coaptation of the
tricuspid valve with severe regurgitation.
Several vegetations were seen on the tricuspid
valve 2 that were larger on the anterior
leaflet, and the other on the septal leaflet
(figure 3). There was small to moderate
pericardial effusion. The blood cultures were
positive for Enterococcus species. The patient
was treated with inotropes for cardiogenic shock,
appropriate antibiotics and anticoagulants. In
summary, a 7-year-old Hispanic male, with a past
medical history significant for known VSD
presented with long standing anemia, easy
fatigability and chest pain and nocturnal fevers.
He has been found to have intracardiac
vegetation, pericardial effusion, microcytic
anemia, thrombocytopenia, hematuria, DIC,
petechiae, pleuritic chest pain, and
hepatosplenomegaly and several positive blood
cultures for enterococcus. For the diagnosis of
infective endocarditis patient had the following
Modified Dukes Criteria 2 major (oscillating
intracardiac mass, positive blood culture) and 2
minor criteria (predisposing perimembranous VSD,
fever). Patient went into right sided congestive
heart failure with hepatomegaly, jugular venous
distention and hyperdynamic precordium secondary
to severe tricuspid regurgitation. Additional
contributors to congestive heart failure were are
anemia, pleural effusion and sepsis. The
remained in severe congestive heart failure (New
York Heart Assocciation stage IV). Hence patient
was transferred to an outside hospital and
underwent repair of both, the VSD and tricuspid
valve and was discharged after finishing a
six-week course of intravenous antibiotics.
However, 5 months after discharge he was noted to
have exercise intolerance and hepatomegaly with
severe tricuspid regurgitation. He was
hospitalized at Childrens Memorial Hermann
Hospital and underwent open heart surgery with
tricuspid valve repair. In 2 days he developed
increasing tricuspid regurgitation, he was again
taken to the OR and another attempt was made to
repair the valve without replacing it with
prosthetic valve. In the OR there did not appear
to be any coaptation of the central portion of
the valve. At this point, a St. Jude Taylor
mitral valve ring was sewn in place. However,
after testing the tricuspid valve after placement
of this ring, there appeared to be residual
severe tricuspid valve regurgitation. The ring
also appeared to be somewhat deformed. The ring
was then removed. A modified Alfieri stitch was
placed. This again failed to repair the tricuspid
valve regurgitation. Finally, after removal of
the Alfieri stitch, commissural sutures were
placed with pledgeted 4-0 Prolene stitches. There
was no tricuspid valve regurgitation after
placement of these commissural stitches. He had
no further complications following his second
surgery that again attempted the repair of the
tricuspid valve with moderate regurgitation
(figure 4) and was asymptomatic at a one-year
follow-up visit.
In 2007, The American Heart Association (AHA)
released a statement to update the
recommendations for the prevention of infective
endocarditis (IE) that were last published in
1997. The major changes in the updated
recommendations included that only an extremely
small number of cases of IE might be prevented by
antibiotic prophylaxis for dental procedures even
if such prophylactic therapy were 100 effective
and that infective endocarditis prophylaxis for
dental procedures is reasonable only for patients
with underlying cardiac conditions associated
with the highest risk of adverse outcome from
infective endocarditis. No IE prophylaxis was
recommended for lesions such as ventricular
septal defects (VSD). The committee also
concluded that scientific proof was lacking to
support the assumptions that dental procedures
may cause IE in patients with underlying cardiac
risk factors and that antibiotic prophylaxis was
effective. The collective published evidence
suggested that of the total number of cases of IE
occurring annually, it was likely that an
exceedingly small number was caused by
bacteremia-producing dental procedures. We
report a 7-year-old Hispanic male with a past
medical history significant of a small
perimembranous VSD and left ventricular to right
atrial shunt, who was diagnosed with IE. The
patient had a dental hygiene visit (during which
no prophylactic antibiotics were administered)
approximately 3 weeks prior to beginning of
symptoms. The echocardiogram revealed vegetations
on the tricuspid valve and the blood cultures
were positive for Enterococci which are usually
not related to dental sources. The patient
subsequently underwent 3 open heart surgeries to
repair a severely regurgitant tricuspid valve.
These findings together with the echocardiogram
are reported. Key Words cardiovascular
diseases endocarditis prevention antibiotic
prophylaxis small perimembranous ventricular
septal defect, enterococcus, dental procedure,
left ventricular to right atrial shunt.
The prognosis from a small ventricular septal
defect (VSD) is usually thought to be excellent
and the risk of endocarditis in a population
informed of the need for antibiotic prophylaxis
is small as concluded by one study 1. Tricuspid
valve endocarditis is seen with small
perimembranous VSD more often when there is
additional left ventricular to right atrial shunt
2 similar to the lesion of our patient
described in the case report. Dental events
were still the most common and even increasing
causal factor 3. The reported incidence of
dental infected endocarditis (IE) varies from 11
to 40, depending on whether invasive procedures
or poor dental hygiene is taken into
consideration 3 . Ten of the IE cases were
found to be related to recent dental work 8
patients had received adequate prophylaxis 3.
This shows that prophylaxis is not always
protective. Streptococci are the most common
micro-organisms related to dental sources as
persistent major causes of IE. The enterococci
are unusual strain of streptococci because they
are much less susceptible to penicillin.
Enterococcal endocarditis is less common in
children (4 of the cases) compared to adults.
This strain inhabits the gastrointestinal and
genitourinary tracts and may enter the blood
stream after instrumentation to these areas.
Hence our patient may not have developed the
endocarditis from the dental procedure. The new
recommendations by the Committee of the AHA seem
evidence based 4 and appropriate as
prophylaxis for the dental cleaning would not
have prevented endocarditis in this
patient. Bibliography. 1. Glen S, Burns J,
Bloomfield P. Prevalence and development of
additional cardiac abnormalities in 1448 patients
with congenital ventricular septal defects.
Heart. 2004 Nov90(11)1321-5. 2. Wu MH, Wang
JK, Lin MT, Wu ET, Lu FL, Chiu SN, Lue HC.
Ventricular septal defect with secondary left
ventricular-to-right atrial shunt is associated
with a higher risk for infective endocarditis and
a lower late chance of closure. Pediatrics. 2006
Feb117(2)e262-7. 3. Di Filippo S, Delahaye F,
Semiond B, Celard M, Henaine R, Ninet J, Sassolas
F, Bozio A. Current patterns of infective
endocarditis in congenital heart disease. Heart.
2006 Oct92(10)1490-5. 4. Wilson W, Taubert KA,
Gewitz M, et al American Heart Association
Rheumatic Fever, Endocarditis, and Kawasaki
Disease Committee American Heart Association
Council on Cardiovascular Disease in the Young
American Heart Association Council on Clinical
Cardiology American Heart Association Council on
Cardiovascular Surgery and Anesthesia Quality of
Care and Outcomes Research Interdisciplinary
Working Group. Prevention of infective
endocarditis guidelines from the American Heart
Association a guideline from the American Heart
Association Rheumatic Fever, Endocarditis, and
Kawasaki Disease Committee, Council on
Cardiovascular Disease in the Young, and the
Council on Clinical Cardiology, Council on
Cardiovascular Surgery and Anesthesia, and the
Quality of Care and Outcomes Research
Interdisciplinary Working Group. Circulation.
2007 Oct 9116(15)1736-54.

CASE REPORT
A 7-year-old Hispanic male with a past medical
history significant for a small perimembranous
ventricular septal defect (VSD) underwent a
dental hygiene procedure on October 29, 2006 .
Approximately 3 weeks later he was admitted to an
outside hospital with fever and chest pain for 1
week and mother was told that his CXR showed
pneumonia and patient was treated with
intravenous antibiotics during the
hospitalization. He was also noted to have anemia
and was prescribed multivitamin for the same.
After discharge patient did not have any
recurrent fever and was not on antibiotics. After
a few weeks he started to complain of mild
decrease in exercise tolerance . He continued to
have chest pain that was worse on inspiration and
relieved with rest. The pain was graded 8/10 and
was over the left side of the chest and sometimes
over right side of the chest. He subsequently
presented to the emergency room at Childrens
Memorial Hermann Hospital in February 2007
complaining of fever, a rash, and chest pain. The
patient had history of nocturnal fever on and off
for past 1 week, not measured by thermometer. The
patient has not had any night sweats. Mom reports
that the child began developing tiny red spots on
his bilateral lower extremities, which then
progressed to his abdomen and scattered ones on
the back of his trunk now, starting approximately
2 weeks ago. He has had a dry cough for the past
2 months per the mother. On the day of admission,
the child went to school however he had increased
work of breathing and increased chest pain with
inspiration. The child also had 3 episodes of
emesis over the past several days, with poor
apetite, only taking fluids and continued to have
normal urine output. Mother had also noted
decrease in activity level with easy
fatiguability and weight loss over past 4 months.

RA
CONCLUSIONS
PE

• Small perimembranous ventricular septal defects,
  especially the ones with left ventricular to
  right atrial shunts can cause IE.
• Enterococcus species can rarely be seen as a
  cause of IE in children without any prior
  gastrointestinal or genitourinary procedure.

Figure 2. EKG shows sinus tachycardia and
possible right ventricular hypertrophy
Figure 3. Echocardiogram in the apical 4
chambered view showed pericardial effusion (PE),
right atrial dilatation (RA), and vegetation
(arrow) on the tricuspid valve
Figure 1. CXR shows cardiomegaly, hepatomeglay
and splenomegaly
Figure 4. Echocardiogram in the parasternal
long-axis view, postoperative moderate residual
tricuspid valve regurgitation