Download Atrial Septal Defect

Artial Septal Defect
J.A. Moutiris, MD, MSc, PhD,
FESC
Department of Cardiology
Paphos General Hospital
Atrial Septal Defect
By:
Aspasia Spyrou(1), Ifigeneia Charalambous(2), Joseph Moutiris(3), Christos Kontos(3),
Ariadni Stylianou(3), Ioannis Michaelides(3),Petros Mavrommatis(3)
(1) final year medical student, Royal College of Surgeons in Ireland
(2) final year medical student, University of Ioannina, Greece
(3) cardiologists, cardiology dept, paphos general hospital
Simple definition
• ASD is a hole in the wall (septum) that
separates the two upper chambers (atria)
of the heart. The defect allows blood to
flow from one atrium to the other, usually
from the left side to the right side. This
causes extra blood flow:
• In the right atrium
• In the right ventricle
• To the lungs
Incidence
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Second commonest congenital heart defect.
5-10% of all cases of CHD,22-40% in adults.
2:1 female to male predominance.
More than 3,000 children are affected in the U.S
every year.
• Ostium secundum type more common 60-70%.
• Ostium primum 30%.
Etiology
• foramen ovale – a large oval opening in
the septum secundum. When infant takes
first breath, higher pressure in left atrium
slams septum primes against foramen
ovale. Over time, the edges of the foramen
ovale fuse with the septum primum and
the adult remnant is the fossa ovalis.
Ostium
Secundum
septum primum
continued..
• septum primum – first part of the interatrial
septum, grows from the roof of the atrium
towards the floor. It is thin, and doesn’t quite
reach the floor. The gap that persists is the
ostium primum. When it does reach the floor it
perforates, and the holes coalesce into the
ostium secundum. The septum primum forms
the flap that covers the foramen ovale.
• septum secundum – A second ridge of tissue
that descends from the roof of the atrium as the
osteum secundum is coalescing. The foramen
ovale forms in the septum secundum.
In a nutshell…
• Two main types of ASD
• Foramen ovale if the defect is in the ostium
secundum.
• Or an ostium primum defect which results in:an
inter-atrial communication, abnormal
atrioventricular junction and abnormal
atrioventricular valves-hallmark is a trileaflet
valve.
Other Congenital heart defects
• Fallot’s tetralogy includes: ventricular
septal defect, overriding of the aorta,
pulmonary hypertension and right
ventricular hypertrophy.
• Eisenmerger’s syndrome=VSD with
pulmonary hypertension.
• Valve atresias
• Coarctation of the aorta
• Transposition of the great vessels
ASD in Ellis-van Creveld Dysplasia
• Skeletal dysplasia
• Affetcs 1:60,000 births.
• Commonest amongst
Ammish people of
Pensylavania and in
Western Australia.
• Autosomal recessive
• Recent studies have
shown 2 mutations on
chromosome 4 (4p16).
Clinical Picture of EVD
• EVD is characterized by dental abnormalities,
natal and small teeth and pseudocleft.
• Shortening of lower limbs, polydactyly,
hypoplastic finger nails, progressive genu valgus
and knock-knees.
• 60% have congenital heart defects most
commonly ASD.
• Genitourinary anomalies
• Hydrocephalus.
• Note that referral to a cardiologist is highly
recommended.
In summary
Signs and symptoms
• Systolic ejection murmur at left lower sternal
border.
• Widely split S2
• Loud S1
• Small defects can be asymptomatic.
• Large defects may cause dyspnea, poor feeding
in children, poor growth, recurrent respiratory
infections and TIAs in unusually young adults.
Diagnosis
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Clinical Examination
CXR
ECG
Echocardiogram with Doppler
Trans esophageal echo with saline
Cardiac catheterization
The CXR and the ECG
The ECG of a patient showing right heart
hypertrophy: peaked P and R waves as
well as deep S on V1 and V6.
The CXR of a patient
demonstrating significant
cardiomegalyand
pulmonary congestion due
to an ASD.
Transoesophageal echocardiogram
Transoesophagial echocardiogram with saline
solution
Patent
foramen
ovale
Antenatal screening for ASD
• Antenatal diagnoses rates are poor and this is of great
importance when counseling parents with an apparently
normal fetal scan.
• Trisomy 21 or Down’s syndrome is strongly associated
with congenital heart disease with primum ASD being
the commonest one. Soft markers on fetal ultrasound
such as endocardial cushions can be misleading and
therefore in cases of suspicion for Down’s syndrome
amniocentesis or chorionic villus sampling should be
advised.
Facts on Newborn examination
• A meta-analysis was carried out in the U.K, in
2005 and included 100,000 live born infants.
The study concluded:
• 121 infants with life threatening congenital heart
disease were undiagnosed at screening of
whom 82 and 83 were diagnosed by pulse
oximetry and echocardiography respectively.
more..
• Only 39 were diagnosed by clinical examination
alone.
• 46 false-positive diagnoses based on a clinical
examination.
• Pulse-oximetry and echocardiography are
accurate and cost-effective methods of
diagnosing CHD including an ASD.
• Early detection through newborn screening can
improve the outcome.
Treatment
• Elective surgical repair is done in preschool years or
when diagnosed in older adults.The latest studies have
shown that it is better if left untreated until adulthood and
repaired after manifestation of symptoms.
• 2-4 hours to complete under GA.
• Or percutaneous procedure that takes 30 mins.
• 2 main types of ASD closure devices: Amplatzer® Septal
Occluder System and the HELEXTM Septal Occluder.
• Exclusion criteria: very large ASD, blood clots in the
heart, other heart defects, if patient’s heart structure
won’t allow the device (i.e not enough atrial septal tissue
present), active infection anywhere in the body, bleeding
disorder or the patient is not suitable for aspirin.
• Also important is endocarditis prophylaxis.
AGA Medical Corporation
Childhood Vs adulthood
• The best point in time to treat and aim the
closure of the defect is controversial.
• Some doctors support the theory that the sooner
is treated the better the quality of life for the
patient.
• However, recent studies have shown that the
outcome is better after manifestation of the
symptoms. This theory is becoming more
accepted since adulthood is a better time to
evaluate the ASD in terms of its size, severity
and impact on the patient.
Complications of transcatheter occlusion
Journal of American College of Cardiology. 2002. March 20,vol 39,No 6. 1061-5
• CardioSEAL/STARFlex (CS/SF) devices were
used in 159 patients and Amplatzer Septal
Occluder (ASO) in 258 patients. The study took
place from December 1996 until January 2001.
• Complications were:
• Embolization in the main pulmonary
artery(3.5%).
• Malposition(3.5%).
• Arrhythmias especially atrial fibrillation (in 6
patients).
Continued..
• Pericardial effusion (in 2 patients).
• Thrombus formation was seen in a 67-year old
patient. To avoid this complication antiaggregation therapy was advised one day
before the procedure.
• Rupture of sizing balloon (in one patient).
• Right iliac vein dissection, groin hematoma due
to human mismanagement (in 3 patients).
• One sudden death after 1.5 years.
Complications if ASD left untreated
• Enlargement of the right atrium and the right
ventricle.
• Right heart overload. The right side of the
heart has to work harder to pump extra blood to
the lungs, especially as resistance in the
pulmonary artery increases. Over time, the heart
may become overworked, and function may
become impaired.
• Arrythmias
• Stroke
• Pulmonary artery hypertension
Migraines and ASD
• In a study that took place in the University
Hospital Gasthuisberg of Belgium, 2005,a
migraine prevalence of 30% was found in
patients with secundum type ASD. After
percutaneous closure with Amplatzer ASD
Occluder the prevalence remained the same but
the frequency of migraine attacks were reduced
significantly over a follow-up period of at least 2
years.
Prognosis
• Spontaneous closure may occur in the first
year of life.
• Most patients are asymptomatic until
adulthood.
• Symptoms may develop in the 3rd decade.
• Pulmonary hypertension, atrial
dysrhythmias, heart failure, and tricuspid
and mitral regurgitation are all potential
findings.
• Post-operative results are excellent.
The future: ASD and Genetics
Nature Genetics. 2005. Feb. 37, 425-8. Mutation in myosin heavy chain 6
causes ASD.
• Mutation on 14q12 was found in a family with
dominantly inherited ASD. A missense mutation
1820N in α-myosin heavy chain (MYH 6) a
structural protein that is highly expressed in the
developing atria.
• The factor that regulates MYH 6, called
transcription factor TBX-5, was also found to
play a role.
• The data provide evidence for a connection
between a structural protein, a transcription
factor and ASD. There are still a lot of questions
to be answered.
Artial Septal Defect
J.A. Moutiris, MD, MSc, PhD, FESC
Department of Cardiology
Paphos General Hospital