2. Introduction
• A ventricular septal defect (VSD) is a hole or a defect in
the septum that divides the 2 lower chambers of the
heart, resulting in communication between the
ventricular cavities.
• VSDs were first clinically described by Roger in 1879.
3. Incidence & Prevalence
• A VSD is the most common congenital cardiac anomaly.
• It may be an isolated defect or part of a complex
malformation.
• The incidence of VSDs is approximately 2 per 1000 live
births.
• Prevalence among school-age children has been
estimated as 1 per 1000.
• Males and females are affected equally.
4. Association
• Coarctation of the aorta
• ASD
• PDA
• Intracardiac obstructions such as-
• Subpulmonary or subaortic stenosis
• Mitral stenosis, and
• Anomalous muscle bundle of the right ventricle
• Incompetent atrioventricular valves.
6. Classification: Based on anatomical location
a) A small membranous
portion and
b) A large muscular portion:
a) The inlet septum,
b) The outlet septum
c) The trabecular septum:
I. Anterior
II. Posterior
III. Mid
IV. Apical
7.
8. Perimembranous defects
• The membranous defect involves varying amounts of
muscular tissue adjacent to the membranous septum
(perimembranous VSD).
• According to the accompanying defect in the adjacent
muscular septum, perimembranous VSDs have been
called perimembranous inlet, perimembranous
trabecular, or perimembranous outlet (tetralogy type)
defects.
• Perimembranous defects are most common (70%).
9. A. Perimembranous inlet
(“AV canal-type”) VSD
B. Perimembranous
trabecular VSD
C. Perimembranous
infundibular VSD
D. Inlet muscular VSD
E. Trabecular muscular VSD
F. Infundibular or outlet
muscular VSD
G. Subarterial infundibular
(supracristal) VSD
10. • The “Swiss cheese” type of multiple muscular defect
(involving all components of the ventricular septum) is
extremely difficult to close surgically.
11. Gerbode defect
• Located in the
membranous portion of
the atrioventricular
septum.
• A Left Ventricular to
Right Atrial defect.
• Uncommon, small.
12. Classification: Based on size
• Small VSD: defect size is less than one-third of
the size of the aortic root,
• Moderate VSD: defect size is less than one-half
of the size of the aortic root, and
• Large VSD: defect size is equal to or larger than
the size of the aortic root.
13. Classification: Based on Pressure
• Restrictive VSD: Qp/Qs ≤ 1.4:1
• Moderately restrictive VSDs: Qp/Qs = 1.4 to
2.2:1
• Nonrestrictive VSDs: Qp/Qs > 2.2:1
14. Classification: Based on ventriculography
A. Tubular type
B. Window type
C. Aneurysmal type
D. Infundibular type
15. Embryology
• Partitioning of the ventricular mass begins as a muscular ridge in
the floor of the ventricle near the apex.
• This ridge later undergoes active growth, which forms the
muscular ventricular septum.
• Concomitantly, the endocardial cushions fuse and the two
regions meet, completing closure of the interventricular foramen
16. Natural history
• Approximately 25% of small defects close spontaneously by
18 months, 50% by 4 years, and 75% by 10 years.
• A spontaneous closure rate approaching 45% within the first
12 to 14 months has been observed among infants with an
uncomplicated perimembranous or muscular VSD in the
neonatal period.
• Even large defects tend to become smaller.
• Defects close by two mechanisms:
a) by muscular septum growth and
b) by “aneurysmal tissue” from a septal leaflet of the tricuspid
valve as in the case of perimembranous defects.
17. Natural history (Contd.)
• Endocarditis is a risk because of the presence of a
high-velocity, turbulent jet into the right ventricle.
• Endocarditis most frequently involves the septal
leaflet of the tricuspid valve apparatus at the point
of jet impact.
18. Natural history (Contd.)
• A large VSD during childhood is typically associated with
significant left-to-right shunt and eventual development
of congestive heart failure.
• Patients with moderate-sized VSDs can survive to
adulthood before detection.
• Given the gradual development of symptoms in these
patients, they may not present until late in the disease
course.
• In these patients, the excess right-sided flow may lead
to pulmonary vascular disease and Eisenmenger
physiology if left untreated.
19. Natural history (Contd.)
Risk factors for decreased survival include:
1. Cardiomegaly seen on the chest radiograph
2. Elevated pulmonary artery systolic pressure (> 60
mm Hg and/or more than one-half of the systemic
pressure)
3. Cardiovascular symptoms such as shortness of
breath, fatigue, or dyspnea on exertion; and
4. Progressive aortic insufficiency
21. History
• With a small VSD, the patient is asymptomatic with
normal growth and development.
• With a moderate to large VSD, delayed growth and
development, decreased exercise tolerance, repeated
pulmonary infections, and CHF are relatively common
during infancy.
• With long-standing pulmonary hypertension, a history
of cyanosis and a decreased level of activity may be
present.
22. Physical Examination
• Infants with small VSDs are well developed and
acyanotic.
• Before 2 or 3 months of age, infants with large VSDs
may have poor weight gain or show signs of CHF.
• Cyanosis and clubbing may be present in patients
with pulmonary vascular obstructive disease
(Eisenmenger’s syndrome).
23. Precordium
• A systolic thrill may be present at the lower left sternal
border.
• Precordial bulge and hyperactivity are present with a
large-shunt VSD.
• The intensity of the P2 is normal with a small shunt and
moderately increased with a large shunt.
• The S2 is loud and single in patients with pulmonary
hypertension or pulmonary vascular obstructive disease.
24. • A grade 2 to 5 of 6 systolic murmur is audible at the lower left
sternal border.
• It may be holosystolic or early systolic.
• An apical diastolic rumble is present with a moderate to large
shunt.
• With infundibular VSD, a grade 1 to 3 of 6 early diastolic
decrescendo murmur of AR may be audible.
25. Electrocardiography
• With a small VSD, the ECG findings are normal.
• With a moderate VSD, left ventricular hypertrophy (LVH)
and occasional left atrial hypertrophy (LAH) may be
seen.
• With a large defect, the ECG shows biventricular
hypertrophy (BVH) with or without LAH.
• If pulmonary vascular obstructive disease develops, the
ECG shows RVH only.
27. Radiography
• Cardiomegaly of varying degrees is present and involves
the LA, left ventricle (LV), and sometimes RV.
• Pulmonary vascular markings increase.
• The degree of cardiomegaly and the increase in
pulmonary vascular markings directly relate to the
magnitude of the left-to-right shunt.
• In pulmonary vascular obstructive disease, the main PA
and the hilar PAs enlarge noticeably, but the peripheral
lung fields are ischemic.
28.
29. Echocardiography
• Two-dimensional and Doppler echocardiographic
studies can identify :
Number, size, and exact location of the defect
Estimate PA pressure by using the modified
Bernoulli equation
Identify other associated defects and
Estimate the magnitude of the shunt.
30. Location of the various types of VSD when
viewed using 2D Echo
31.
32. • In the standard parasternal long-axis view (A1), the ventricular septum consists of (from the
aortic valve toward the apex) the infracristal outlet (Inf-C outlet) septum (the VSD of tetralogy
of Fallot is seen here) and the trabecular (mid- and apical) septum.
• In the parasternal right ventricular outlet tract (RVOT) view (A2), the septum consists of
supracristal outlet (Sup-C outlet) septum and the trabecular septum.
• In the parasternal short-axis view showing the aortic valve (B1), the membranous septum is
toward the 10 o’clock direction, the infracristal outlet septum at the 12 o’clock direction, and
the supracristal outlet septum immediately adjacent to the pulmonary valve.
• The ventricular septum at the mitral valve (B2), the posterior muscular septum is inlet (INLET)
septum.
• The ventricular septum at the papillary muscle (B3) is all trabecular septum, so that one can
easily classify the defect into anterior (ANT), mid- (MID), and posterior (POST) trabecular
defects.
• In the apical four-chamber view showing the coronary sinus (C1), the ventricular septum is
the posterior (POST) trabecular septum.
• In the apical four-chamber view showing both atrioventricular (AV) valves (C2), the septum
immediately beneath the tricuspid valve is the inlet septum (INLET) and the remainder is the
mid- and apical septa.
• The thin septum between the insertion of the mitral and tricuspid valves is the AV septum
(C2), a defect which can result in a left ventricle (LV)–to–right atrium (RA) shunt.
• In the standard apical four-chamber view, the membranous septum is not visible. In the apical
“five-chamber” view (C3), the membranous (MEMB) septum is seen beneath the aortic valve,
and below it is the infracristal outlet (Inf-C outlet) septum.
33. • The ventricular septum seen in the subcostal four-chamber
view (D1) is similar to the apical four-chamber view (C2).
• With anterior angulation of the horizontal transducer, the LV
outflow tract (LVOT) is seen (D2), and the septum seen here is
similar to the apical “five-chamber” view (C3).
• With further anterior angulation, the RVOT is seen (D3). The
superior part is the supracristal outlet (Sup-C outlet) septum,
and the inferior part is the anterior (ANT) trabecular septum
(D3).
• The subcostal short-axis view showing the RVOT (E1) is
orthogonal to the standard subcostal four-chamber view and
is an important view for evaluating the site and size of a VSD.
• In this view, both supracristal outlet (Sup-C outlet) and
infracristal outlet (Inf-C outlet) septa (in that order) are seen
beneath the pulmonary valve and the trabecular septum (ANT
and POST) is seen apical ward.
• The ventricular septum seen at the papillary muscle (E2) is all
trabecular septum and is similar to the parasternal short axis
view (B3).
34.
35. Cardiac Cath
• Shows an increase in oxygen saturation at the right
ventricular level and pulmonary artery level, reflecting
the left-to-right ventricular shunt.
• With small defects, the right ventricular and pulmonary
arterial systolic pressures are normal.
• With large defects, these pressures are at or near
systemic levels.
• LV graphy:
• to determine the exact site, size, and number of septal
defects.
• to establish the spatial relations of the great arteries to each
other and to the ventricles.
• Aortography: PDA, CoA
38. Medical
• Treatment of CHF:
Rest
O2 inhalation
Diuretics
Digoxin
Vasodilators
• Prophylaxis for IE
• No exercise restriction is required in the absence
of pulmonary hypertension.
39. Device closure
• Trabecular VSDs have proved more amenable to this
technique because of their relatively straightforward
anatomy and a muscular rim to which the device
attaches well and therefore results in excellent closure
rates with low procedural mortality.
• Closure of perimembranous VSDs is technically more
challenging because of their proximity to valve
structures; careful patient selection is required.
40. • The Amplatzer muscular VSD occluder consists of three
components: an LV disk, a connecting waist, and an RV
disk.
• Polyester fabric is present in both disks and the
connecting waist.
44. Surgical
Indications:
• A significant L-R shunt with Qp/Qs of greater than
2:1 is an indication for surgical closure.
• Surgery is not indicated for a small VSD with Qp/Qs
less than 1.5:1.
45. Timing:
• Infants with CHF and growth retardation unresponsive to
medical therapy should be operated on at any age, including
early infancy.
• Infants with a large VSD and evidence of increasing PVR
should be operated on as soon as possible.
• Infants who respond to medical therapy may be operated on
by the age of 12 to 18 months.
• Asymptomatic children may be operated on between 2 and 4
years of age.
Contraindications:
• PVR/SVR ratio of 0.5 or greater or
• PVOD with a predominant R-L shunt.
46. Procedure
• PA banding as a palliative procedure is no longer
performed unless additional lesions make complete
repair difficult.
• Direct closure of the defect is carried out under
hypothermic cardiopulmonary bypass, preferably
without right ventriculotomy.
• Most perimembranous and inlet VSDs are repaired by a
transatrial approach.
• Outlet (conal) defects are best approached through an
incision in the main pulmonary artery.
• Apical VSD may require apical right ventriculotomy.
48. Mortality
• The surgical mortality rate is less than 1%.
• The mortality rate is higher for-
Small infants younger than 2 months of age,
Infants with associated defects, and
Infants with multiple VSDs.
49. Complications
• RBBB is frequent in patients repaired via right
ventriculotomy.
• Complete heart block requiring pacemaker occurs
in 1% to 2% of patients.
• Residual shunt occurs in fewer than 5%.
• The incidence of neurologic complications is
directly related to the circulatory arrest time.
50. Reproductive Issues
• Pregnancy is well tolerated in women with small or
moderate VSDs and in those with repaired VSDs.
• Pregnancy is contraindicated in women with
Eisenmenger syndrome because of high maternal
(≈50%) and fetal (≈60%) mortality.
