2. Overview
Left Ventricular Outflow Tract Obstructions(LVOTO)
are stenotic lesions that start in the anatomic left
ventricular outflow tract (LVOT).
Obstructions are to forward flow of blood
Lesions impose increased afterload on the left
ventricle
If left untreated results in hypertrophy and failure of
the left ventricle.
3. Clinical Manifestations
Brisk and dramatic presentation soon after birth
Decreased systemic and coronary perfusion
Acute hemodynamic deterioration
Cardiovascular collapse
End organ injury
Shock
4. Clinical Manifestation
Shortness of breath
Fatigue
Chest pain often after exercise
Sensation of rapid, fluttering, or pounding heart beats
Dizziness or fainting
5. Aortic Stenosis
Aortic Stenosis
Normal valve has three parts (leaflets and cusps)
Stenotic valve may be unicuspid (1 cusp) or bicuspid
( 2 cusps)
Stenotic valve is thick and stiff
Obstruction vs. Insufficiency
Aortic Insufficiency (Aortic Incompetence) – blood
flows backward from a widened or weakened aortic valve
into the left ventricle.
Obstruction causes the heart to work harder to pump
blood throughout the body
6.
7. Subaortic Stenosis (SAS)
May be due to a discrete fibrous membrane
Muscular narrowing
Or a combination of the 2
Bicuspid Aortic Valve with Coartication of the Aorta
EKG Usually normal
Doppler demonstrates a focal or diffuse narrowing of the
LVOT
Aortic regurgitation may result due to SAS
8. Coartication of the Aorta
Coartication of the Aorta
One of the more common heart conditions present at birth
More common in persons with genetic disorders such as
Turners Syndrome
Most often diagnosed in children or adults under 40 years
old.
Patients that present with Coartication of the aorta may
also have weak areas in the walls of the blood vessels of
their brain, putting them at an increased risk for stroke.
9.
10.
11. Hypoplastic Left Heart
Syndrome
Birth defect in which the left side of the heart does not
form correctly --- as a result blood flow through the
heart is affected.
Affects a number of structures on the left side of the
heart:
Left Ventricle
Mitral Valve
Aortic Valve
Ascending portion of the aorta
*Many pts that have HLHS also have an atrial septal defect.
12.
13.
14. Surgical Intervention
Aortic Valve Stenosis
Balloon valvuloplasty. Occasionally, balloon valvuloplasty
is an option.
Aortic valve replacement. This is the primary surgical
treatment for severe aortic valve stenosis.
Transcatheter aortic valve replacement (TAVR)
Surgical valvuloplasty.
15. Treatment/Plan of Care
Resuscitate patients
Administer prostaglandins
Restore ductal patency
Assess the levels of obstruction
Assess for other cardiac abnormalities and related
hypoplasia of the aortic arch and left heart structures.
Surgical Intervention
16. Outcomes
All patients with LVOTO are at risk for infective
endocarditis
Infection of the endocardial surface of the heart or the
heart valves; caused by bacteria and high risk heart
conditions).
Once a patient has IE, they are at a high risk for getting it
again even If they do not have heart disease.
17. Outcomes
A new study has confirmed that the presence of
LVOTO in about ¼ of the patients with hypertrophic
cardiomyopathy is a strong independent indicator of
progression to severe symptoms of heart failure and
death.
Editor's Notes
Function. During systole, the ventricles contract, pumping blood through the body. During diastole, the ventricles relax and fill with blood again. The left ventricle receives oxygenated blood from the left atrium via the mitral valve and pumps it through the aorta via the aortic valve, into the systemic circulation.
A ventricular outflow tract is a portion of either the left ventricle or right ventricle of the heart through which blood passes in order to enter the great arteries.
Afterload is the pressure in the wall of the left ventricle during ejection
Properly Working Valves Should…..
The valve is properly formed and flexible.
The valve should open all the way so that the right amount of blood can pass through
The valve closes tightly so that no blood leaks back into the chamber.
Congestive heart failure in adults
Reduced antegrade blood flow into the aortic valve predisposes fetus to underdevelopment of the left heart structures and hypoplasia of the mitral valve, left ventricle and aortic arch
Aortic Valve Stenosis weakens the heart and if untreated can lead to heart failure.
An infant or child with Aortic Valve Stenosis may not show any signs or symptoms, depending upon the amount of narrowing.
Chest pain (angina) or tightness
Feeling faint or fainting with exertion
Shortness of breath, especially with exertion
Fatigue, especially during times of increased activity
Heart palpitations — sensations of a rapid, fluttering heartbeat
Heart murmur
Signs and symptoms generally develop when the narrowing of the valve is severe
Subaortic Stenosis is an obstruction or narrowing at the outlet of the lower left ventricle, just below the aortic valve.
25-50% of patients with SAS have associated congenital heart defects including
Ventricular Septal Defect
Patent Ductus Arteriosus
Coartication of the Aorta
Bicuspid Aortic Valve
Shone Complex
Atrioventricular septal defect
In most cases SAS is detected in the course of follow up care for associated congenital heart defects.
The surgery of choice for discrete fibromuscular SAS is complete resection with myotomy, with or without myomectomy through an aortotomy
The standard approach for coarctation – particularly when identified in neonates and younger patients – is surgical.
The standard approach for discrete aortic narrowing is via an incision between the ribs on the left side of the chest. The aorta sits very far back in the chest cavity next to the spine. Surgeons spread the ribs apart, push the lung out of the way, open up the lining inside the chest that overlies the aorta and, after exposing the aorta, isolate the segment of narrowing between clamps. They then cut out the segment and sew the two ends of the aorta together, usually overlapping the segments to address any milder narrowing of the adjacent segments of the aorta.
About 50% of the children who undergo coarctation repair are treated within the first few months of life. The age of repair for the other 50% spans a wide range, though most cases are identified and repaired during childhood.
Hole increases the amount of blood that flows through the lungs, and over time may cause damage to the blood vessels in the lungs.
The left ventricle is underdeveloped and too small.
The mitral valves is not formed or is very small, stenotic - allows blood to travel from the left atrium to left ventricle; presents as a “opening snap” which is not normal
The aortic valve is not formed or is very small.
The ascending portion of the aorta is underdeveloped or is too small.
atrial septal defect- which is a hole between the left and right upper chambers (atria) of the heart.
Surgical Intervention
Norwood procedure. This surgery is usually performed within the first two weeks of your child's life. Several forms of this procedure may be performed. Surgeons reconstruct the aorta and connect it directly to the heart's lower right chamber (right ventricle). Surgeons insert a tube (shunt) that connects the aorta to the arteries leading to the lungs (pulmonary arteries), or they place a shunt that connects the right ventricle to the pulmonary arteries. This procedure allows the right ventricle to effectively pump blood to both the lungs and the body. In some cases, doctors may perform a hybrid procedure. Surgeons implant a stent in the ductus arteriosus to maintain the opening between the pulmonary artery and aorta, place bands around the pulmonary arteries to reduce blood flow to the lungs, and create an opening between the atria of the heart. After this procedure, your baby's skin will still have a blue cast because oxygen-rich blood and oxygen-poor blood continue to mix within the heart. Once your baby successfully passes through this stage of treatment, the odds of survival may increase, but he or she may still be at risk of death due to complications.
Bi-directional Glenn procedure. This procedure is generally performed when your child is between 3 and 6 months of age, after the first procedure. In this procedure, doctors remove the first shunt attached to the pulmonary arteries, and then connect one of the large veins that normally returns blood to the heart (the superior vena cava) to the pulmonary artery instead. If surgeons previously performed a hybrid procedure, they'll conduct additional steps during this procedure. This procedure reduces the work of the right ventricle by allowing it to pump blood mainly to the aorta. It also allows most of the oxygen-poor blood returning from the body to flow directly into the lungs without a pump. After this procedure, all the blood returning from the upper body is sent to the lungs, so blood with more oxygen is pumped to the aorta to supply organs and tissues throughout the body.
Fontan procedure. This procedure is usually performed when your child is between 18 months and 4 years of age. During this procedure, the surgeon creates a path for the oxygen-poor blood in one of the blood vessels that returns blood to the heart (the inferior vena cava) to flow directly into the pulmonary arteries. The pulmonary arteries then transport the blood into the lungs. This procedure allows the rest of the oxygen-poor blood returning from the body to flow to the lungs. After this procedure, there's no mixing of oxygen-rich and oxygen-poor blood in the heart, and your child's skin will no longer look blue.
Another surgical option is a heart transplant, especially when the defects are complex.
Atrial Septal Defects
Primum Atrial Septal Defect
Superior Sinus Venosus defect
Secundum atrial septal defect
Inferior Sinus venosus Defect
Coronary Sinus Defect
Administration of Prostaglandins prevents the closure of PDA in newborns with particular cyanotic heart defects
