Transcript Tetralogy of fallot for the adult cardiologist

Anne-Marie Anagnostopoulos, MD
Non-Invasive Conference
December 9, 2009
TETRALOGY OF FALLOT FOR THE
ADULT CARDIOLOGIST
Outline
 History and Epidemiology
 Anatomy and Embryology
 Spectrum of TOF
 Surgical Repair
 Imaging The Adult with Repaired TOF
 Summary
Special Thanks
 Special thanks to Dr. Anne Marie Valente who
helped me enormously
History of Tetralogy of Fallot
 1671: Stenson first describes pathology of what
would later be confirmed as TOF
 1888: Etienne-Louis Fallot first recognizes a
group of complex cardiac malformations that
leads to cyanosis and identifies 4 abnormalities:
pulmonary stenosis, VSD, dextroposition of the
aorta, and RVH
 Fallot postulated that these abnormalities resulted
from abnormal development of the subpulmonary
infundibulum and pulmonary valve.
 1924: Abbott and Dawson name the
malformation “Tetralogy of Fallot”
History
 From Wikipedia:
 E. L. A. Fallot.
Contribution à
l’anatomie pathologique
de la maladie bleue
(cyanose cardiaque).
Marseille médical, 1888,
25: 77-93, 138-158, 207223, 341-354, 370-386,
403-420.
Epidemiology
 Overall, congenital heart disease is rare
 However, of the cyanotic congenital heart
abnormalities, TOF is the most common
 TOF has an incidence of approximately 32.6
per 100,000 live births
 The success of early surgical repair has led to
a large population of adults with repaired TOF
Anatomy and Embryology
 The fundamental embryologic malformation
in TOF is abnormal development of the conotruncus (also known as: conal septum,
subpulmonary infundibulum)
 There is hypoplasia of the conotruncus and
anterior/superior displacement of the
infundibular septum
 This results in failure of ventricular septation,
subpulmonary and/or pulmonary valve
stenosis and overriding aorta
The Worlds Best Anatomical Charts. Anatomical Chart Company Skokie, IL. ISBN 0-9603730-5-5.
Anatomy and Embryology in Tetralogy of Fallot
Figures Emily Flynn, Echocardiography in Pediatric and Congenital Heart Disease Editors Lai,
Mertens, Cohen, Geva 2009
Anatomy and Embryology –
Simplified Diagram
2D Echo TOF
Source:
Feigenbaum’s
6th Ed.
Spectrum of Tetralogy
 There is a spectrum of anatomy in TOF with
an associated variation in clinical
presentation
 Children with minimal pulmonary stenosis are
at one end and can be “pink”
 At the other extreme is a form of TOF with
pulmonary valve atresia and VSD (severely
blue)
 In the latter case, life is sustained by PDA or
aorto-pulmonary collateral vessels
TOF:Pulmonary Atresia and VSD
• Obliterated
subpulmonary
infundibulum
• Marked anterior/left
shift of conal septum
•Figure Emily Flynn,
Echocardiography in Pediatric and
Congenital Heart Disease Editors
Lai, Mertens, Cohen, Geva 2009
Anatomy and Embryology:
Coronary Anomalies
 Because the aortic root is rotated in TOF,
coronary artery anomalies can occur
 Most common (3%) is origin of LAD from RCA
 Double LAD occurs 1.8% of time
 Least common anomalies are single RCA or
LCA (0.3% and 0.2% respectively)
Surgical Repair
 Symptomatic infants are repaired early – can be
palliated with a variety of shunts
 Asymptomatic children are usually electively
repaired early as well
 Surgery involves repair of the VSD and
enlargement of the RVOT with infundibular
septum resection +/- use of a transannular patch
 This can usually be performed in one step as long
as pulmonary artery and its main branches are of
adequate size
 The surgery uniformally results in pulmonic
regurgitation
Palliative Shunts
Glenn Shunt
2D Echo Glenn Shunt: SVC->PA
Source:
Feigenbaum’s
6th Ed.
Surgical Repair –
Transannular Patch
Natural History
Patients post-repair do
well up to ~25 yrs postoperatively
Modes of death:
Sudden cardiac death
Arrhythmias
Congestive heart failure
Nollert G. JACC 1997; 30:1374
The Adult with Repaired TOF
 Patients often remain asymptomatic
 Although decreased exercise capacity can
often be elicited with objective testing
 Clinical Presentation: heart failure, dyspnea
on exertion, atrial and ventricular
arrhythmias, syncope, sudden death
 ECG findings include RAD, RVH/RAA and
RBBB; QRS duration can be prolonged
(>180ms is important to note)
Sequelae of TOF Repair
 Residual lesions:
 Ventricular septal defect
 Branch pulmonary artery stenosis
 Tricuspid regurgitation
 Pulmonary regurgitation
 Progressive RV dilation and dysfunction
 Progressive LV dysfunction
 Aortic root dilation
 Exercise intolerance, heart failure, arrhythmias and sudden cardiac
death
Courtesy A. Valente MD
Imaging in Repaired TOF
 Non-invasive imaging is the mainstay of
longitudinal follow-up in previously repaired
TOF
 Echocardiography is used to evaluate:
residual VSD/PS, Ao Root size and associated
AR, PR, and RV/LV function
 CMR is used to determine RV volumes and
severity of PR
 Often these modalities are used in a
complementary fashion
Pulmonary Regurgitation
 Nearly universal
 Severity is dictated by:
 compliance of the RV
 capacitance of the pulmonary arteries
 Early: presence of RVH (↓ RV compliance) and
small PAs (↓ capacitance) →↓ PR
 Late: dilation and thinning of the RV ( ↑
compliance) and dilation of the PAs (↑
capacitance) →↑ PR
Courtesy A. Valente MD
Pulmonary Regurgitation
Courtesy A. Valente
Effects of Chronic PR
 Adaptive mechanisms in chronic PR
 increased RV end-diastolic volume
 increased RV stroke volume
 These mechanisms compensate for the hemodynamic
burden placed on the RV for many years
 Studies in the 1970’s – 1980’s on survivors of TOF repair were
largely asymptomatic (based on self-reporting)
Geva T. STCVS 2006; 9:11.
Effects of Chronic PR
Compensatory
mechanisms exist up
to a certain point, but
ultimately these
mechanisms fail
Courtesy A. Valente MD
Effects of Chronic PR
Good RV Function
Poor RV Function
Courtesy A. Valente
Severity of Pulmonary Regurgitation
• Prospective study of 34 adults with repaired TOF
• Echocardiogram & cardiac MRI within 3 months
• Median age 33 yrs (12 yrs)
• Mean time since initial surgical repair 25  8 yrs
• 13 subjects had undergone transannular patch
• 6 subjects had undergone bioprosthetic PVR
Silversides C. JASE 2003; 16: 1057
Pulmonary Regurgitation
% PR and volume are inversely related to the pressure
half-time: r = -0.6, p <0.001
Mild PR
Severe PR
Silversides C. JASE 2003; 16: 1057
Pulmonary Regurgitation
• In addition, PHT <100ms had highest sensitivity
and specificity for detecting significant PR (RF
>20%)
Silversides C. JASE 2003; 16: 1057
Biventricular Interaction
 Median age from repair 21
years
 Unfavorable ventricularventricular interaction
 Confirmatory data that RV
mechanics are only part of
the problem
 Patients repaired at older
age, more likely to have
poor clinical status later
Geva T. JACC 2004; 43(6): 1068
RV Function by Echocardiography
 Often adults with repaired TOF cannot
undergo CMR due to devices
 Myocardial Performance Index (MPI) has
been shown to correlate with MRI RVEF
 Retrospective study of 57 adults (repaired
TOF) with a CMR and Echo within 6 months
of each other
 RV MPI = (Doppler duration of TR-RV ejection
time)/RV ejection time
Schwerzmann, M. AJC 2007;99:1593
RV MPI Correlation With CMR RVEF
MPI = (a-b)/b
Schwerzmann, M. AJC 2007;99:1593
RV MPI Correlation With CMR RVEF
Schwerzmann, M. AJC 2007;99:1593
Regional Wall Motion Abnormality
• 85 subjects repaired
TOF underwent MRI
 RVOT outflow
aneurysm/akinesia
present in 57%
 No significant
difference in the type
of repair
 Aneurysm/akinesia
negative effect on
RVEF
Davlouros et al. JACC 2002; 40:2044
Pulmonary Valve Replacement
Operative risk is small: mortality < 2%
What criteria should we use in patient selection?
Traditional indication: patient symptoms
Is there a risk to waiting until patients develop
symptoms?
 Patients may not detect subtle changes in exercise
capacity
 By the time patients notice symptoms, problems
may be severe and irreversible
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*Oosterhof T. Heart 2007; 93: 506
Predictors of Adverse Outcome
 88 subjects with repaired TOF
 Surgical repair between 1966-1987
 CMR between 1997-2001
 Median follow-up from MRI 4.2 yrs
 22 subjects had a major clinical event
 4 deaths
 8 sustained VT
 10 change in NYHA class from good to poor
 Larger RVEDV, LVEF<50%, RVEF<45% by CMR
predicted adverse events
Knauth A. Heart 2008; 94: 211-16.
Proposed Criteria for PVR
 Balance between patient’s clinical status
(exercise capacity, heart failure symptoms,
arrhythmia) and quantitative information
 Decision to do PVR is quite variable center to
center
 Repaired TOF with moderate or severe PR (PR
RF >25% by CMR) and > 2 criteria
 RVEDVi > 160 cc/m2 ( z > 5)
 RVESVi > 70 cc/m2
 LVEDVi < 65cc/m2
 RVEF < 45%
 RVOT aneurysm
 LVEF < 50%
Geva T. STCVS 2006; 9:11.
Aortic Root Dilation
 Aortic root dilation occurs in a
subset of repaired TOF adults
and can lead to significant AR
 May be a result of R L shunt
prior to repair though not
fully understood why it
progresses after
 A small retrospective study
identified risk factors for Ao
root dilation (defined as Ao
root size observed:expected
>1.5)
 Therefore it is important to
closely follow Ao root size
with imaging longterm
Aortic Root Dilation
Niwa, K. Circulation 2002;106:1374
Predictors of Arrhythmia and SCD
 A study in England
evaluated data from 793
repaired TOF patients
 QRS duration >180ms was
found to be predictive of
SCD and ventricular
arrhythmias
 Older age at repair was
associated with
Afib/AFlutter and SCD
 QRS duration rate of
change may also be
significant predictor of
SCD
Gatzoulis, M. Lancet 2002; 356:95
Recommendations
 ECG (QRS duration): every 12 months
 Exercise Testing: every 24-36 months
 Echo: every 24 months
 CMR (RVEDVi, RV/LV EF): every 24 months
 EP testing: when clinically indicated
 Echo and CMR are used together

Authors from CHB
Geva T. STCVS 2006; 9:11.
Summary
 Because of successful childhood repair, larger population of

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adults with repaired TOF exists and can present to adult
cardiologists
Pulmonary Regurgitation is predominant hemodynamic
abnormality leading to RV dilation and dysfunction
Timing of surgery for PR is an area of great interest as
clinical symptoms do not always correlate with severity of
PR and RV dysfunction.
Echo and CMR are used together to follow repaired
patients long term
Aortic root dilation occurs in a subset of patients and must
also be followed closely
QRS duration >180 ms is an important predictor of
ventricular arrhythmias and SCD
References
 Feingenbaum’s Echo Textbook, 6th Ed.
 Echocardiography in Pediatric and
Congenital Heart Disease Editors Lai,
Mertens, Cohen, Geva 2009
 Yale Congenital Heart Disease website:
www.med.yale.edu/intmed/cardio/chd/
 Braunwald’s Textbook Heart Disease