ECHO CONFERENCE 5/11/11 DARRYN APPLETON Ventricular Septal Defects.
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Transcript of ECHO CONFERENCE 5/11/11 DARRYN APPLETON Ventricular Septal Defects.
ECHO CONFERENCE 5/11/11
DARRYN APPLETON
Ventricular Septal Defects
Outline
Morphology, Types & PathophysiologyNatural History and Clinical PresentationSome Echo examplesClinical Scenarios and RecommendationsInterventions: Indications, Surgery,
PercutaneousPregnancy and Endocarditis ProphylaxisReview Questions
Introduction
The most common form of CHD, accounting for up to 20-40% of patients diagnosed with CHD
Impact may range from asymptomatic to pulmonary HTN, LV volume overload and RVH
Morphology: 4 types Membranous – most common type in adults (80%) Muscular – most common type in young children Complete AV septal (endocardial cushion) defects Supracristal (subarterial)
Morphology – The Ventricular Septum
Morphology – The Ventricular Septum
1. Membranous2. Outflow3. Trabecular
septum4. Inflow5. Subarterial /
Supracristal
VSD Types
VSD Types
VSD Types
Pathophysiology
Defect size is often compared to aortic annulus Large: > 50% of annulus size Medium: 25-50% of annulus size Small: <25% of annulus size
Pathophysiology
Restrictive VSD is typically small, such that a significant pressure gradient exists between the LV and RV (high velocity), with small shunt (Qp/Qs ≤ 1.4 : 1)
Moderately restrictive VSD moderate shunt (Qp/Qs 1.4 to 2.2 : 1)
Large / non-restrictive VSD large shunt (Qp/Qs > 2.2 : 1)
Eisenmenger VSD irreversible pulmonary HTN and shunt may be zero or reversed (i.e. RL)
Natural History
Restrictive: typically does not have hemodynamic impact and may close spontaneously Location Location Location: Subaortic may result in
progressive AI
Moderately restrictive: does create LV overload and dysfunction along with variable increase in PVR
Large / non-restrictive: LV volume overload earlier in life with progressive pulm HTN and ultimately Eisenmenger syndrome
Clinical Features
Peds: Murmur Dyspnea, CHF, Failure to thrive
Adults: Asymptomatic murmur – harsh, pansystolic, left
sternal border Mod restrictive – dyspnea, a.fib, displaced apex,
murmur, S3 Non-restrictive Eisenmenger VSD – central cyanosis,
clubbing, RV heave, loud P2
Echo Example 1
Echo Example 1
t
Outlet VSD – Para long axis
Echo Example 2
Echo Example 2
Echo Example 2
Supracristal VSD, with pulm outflow tract obstruction
Echo Example 3
Echo Example 3
Echo Example 3
Echo Example 3
Echo Example 3
Echo Example 3
Type: Size:
MembranousRestrictive
Echo Example 4
Echo Example 4
Echo Example 3
Type:Size: Shunt:
MuscularLarge / Non-restrictiveRL (inc RH pressures)RV dilatedEisenmengers
Clinical Scenarios & Recommendations
Symptomatic young infant with Pulm HTN Early surgery within 3 months. Medical therapy with diuretics +/- ACEI pre-op
Asymptomatic pt without Pulm HTN but with LV overload Closure usually recommended to avoid late LV dysfunction
Asymptomatic pt, small VSD, no LV dilation Conservative
Asymptomatic pt, small VSD but with AI/prolapse Peri-membranous VSD with more than trivial AI should
have surgery
Clinical Scenarios & Recommendations
Eisenmenger Syndrome Supportive Bosentan (Endothelin receptor antagonist) – improves
functional capacity, QOL Sildenafil
Penny DJ, Vick GW. Lancet 2011; 377: 1103-12
Interventions
Indications for Surgical Closure in adults: Evidence of LV volume overload (Class I if Qp/Qs >2,
Class IIa if Qp/Qs > 1.5) History of bacterial endocarditis (Class I) Significant LR shunt with PA pressure < 2/3 systemic
and PVR is < 2/3 SVR
Surgical Closure Considered the first-line choice of therapy for those
with indications Usually involves direct patch closure w cardio-pulm
bypass Operative mortality < 2% in most centers
Long Term Surgical Outcomes
Retrospective review of 46 pts with surgical VSD repair at Mayo Clinic
Mongeon et al. JACC Int 2010; 3: 290-7
Interventional Options
Percutaneous Device Closure Muscular VSDs can typically be closed percutaneously
Class IIb recommendation in Guidelines (i.e. surgery still preferred)
No FDA approved devices for perimembranous VSDs, although there are specific devices for this purpose Concern re proximity of defect to AV node and high risk
of complete AV block requiring pacemaker
Pregnancy and VSDs
Pregnancy well tolerated in women with small to moderate sized VSDs as long as there is no pulmonary vascular involvement
Eisenmenger syndrome: Pregnancy contraindicated due to exceptionally high risk of maternal and fetal death
Endocarditis Prophylaxis for VSD
Uncomplicated VSD – no Abx for dental or other procedures required
Post repair: Abx for 6 months following surgical or percutaneous
repair Indefinite Abx if there is residual shunt
Risk of bacteremia from daily life usually exceeds that of procedure Abx for procedures only prevent small % of cases
Focus should be on optimal dental hygiene for those with CHD
Question 1
An isolated VSD will generally cause enlargement of which chamber(s): A: Left atrium, left ventricle B: Right ventricle C: Right ventricle, pulmonary artery D: Aorta E: Right ventricle, right atrium
Question 1
An isolated VSD will generally cause enlargement of which chamber(s): A: Left atrium, left ventricle B: Right ventricle C: Right ventricle, pulmonary artery D: Aorta E: Right ventricle, right atrium
Question 2
Question 2
The defect shown on the previous slide is a: A: Muscular VSD B: Sinus venosus VSD C: Perimembranous VSD D: Inlet VSD E: Supracristal VSD
Question 2
The defect shown on the previous slide is a: A: Muscular VSD B: Sinus venosus VSD C: Perimembranous VSD D: Inlet VSD E: Supracristal VSD
Question 3
A common complication of this defect is: A: Pulmonary valve endocarditis B: Aortic regurgitation C: Aortic dissection D: Tricuspid regurgitation E: Right ventricular enlargement
Question 3
A common complication of this defect is: A: Pulmonary valve endocarditis B: Aortic regurgitation C: Aortic dissection D: Tricuspid regurgitation E: Right ventricular enlargement
Question 4
There is no diastolic flow in this perimembranous VSD A: True B: False
Question 4
There is no diastolic flow in this perimembranous VSD A: True B: False
Question 5
A restrictive VSD is a simple lesion with a good long term prognosis. However, complications can occur. All of the following are possible complications of a VSD except: A: Endocarditis B: Aortic regurgitation C: Aortic valve prolapse D: Eisenmenger Syndrome E: Right sided volume overload
Question 5
A restrictive VSD is a simple lesion with a good long term prognosis. However, complications can occur. All of the following are possible complications of a VSD except: A: Endocarditis B: Aortic regurgitation C: Aortic valve prolapse D: Eisenmenger Syndrome E: Right sided volume overload
Question 6
Question 6
The pulmonary artery systolic pressure in this patient with a VSD is: A: Normal B: Moderately elevated C: Systemic / Supra-systemic
Question 6
The pulmonary artery systolic pressure in this patient with a VSD is: A: Normal B: Moderately elevated C: Systemic / Supra-systemic
Question 7
A patient with a VSD undergoes TTE. BP measured at the time of the study is 125/75 (right arm), MAP 92. CW doppler across the VSD gives a peak velocity of 5 m/s. Assuming RA pressure of 5, what is the estimated PASP? A: 20mmHg B: 25 mmHg C: 30 mmHg D: 72 mmHg E: 105 mmHg
Question 7
A patient with a VSD undergoes TTE. BP measured at the time of the study is 125/75 (right arm), MAP 92. CW doppler across the VSD gives a peak velocity of 5 m/s. Assuming RA pressure of 5, what is the estimated PASP? A: 20mmHg B: 25 mmHg C: 30 mmHg D: 72 mmHg E: 105 mmHg
VSD Hemodynamics
Peak gradient = 4 x v2 (Simplied Bernoulli equation)
VSD gradient = LV systolic pressure – RV systolic pressure
RVSP = LVSP - VSD gradient RVSP = cuff systolic BP - VSD gradient (or 4
x v2)
Assuming no aortic outflow tract obstruction
PASP = RVSP Assuming no pulmonary outflow tract obstruction