Session 3 - Congenital Heart Disease Flashcards Preview

Semester 2 - CVS > Session 3 - Congenital Heart Disease > Flashcards

Flashcards in Session 3 - Congenital Heart Disease Deck (69):

Give four basic facts you absolutely completely without a doubt have to know about the heart

1. Right Ventricle pumps deoxygenated blood to lungs 2. Pulmonary circulation has low resistance 3. Left ventricle pumps oxygenated blood at systemic blood pressure to Aorta 4. Each ventricle is morphologically adapted for its task


What two features are required for a right to left shunt?

A hole and a distal obstruction


What are the two classes of congenital HD?

Acyanotic and Cyanotic


What are the two main causes of acyanotic congenital heart disease?

Left to right shunts Obstructive lesions


What are the four main causes of cyanotic congenital heart disease?

– Tetralogy of Fallot (VSD/Pulm stenosis …) – Transposition of the Great Arteries – Total Anomalous Pulmonary Venous Drainage – Univentricular Heart


What are the four haemodynamic effects of atrial septal defects?

1. Increased pulmonary blood flow 2. RV Volume overload 3. Pulmonary hypertension is rare 4. Eventual Right Heart Failure


What are four haemodynamic effects of ventricular septal defects?

1.Left to right shunt 2. LV Volume overload 3. Pulmonary Venous congestion 4. Eventual pulmonary hypertension


How common is a ventricular septae defect?

Makes up 25% of all forms of congenital heart defects


What is the most common site for a ventricular septal defect, and why does it occur?

Membranous part of IVS develops seperatel from muscular part, so is a common site for VSD


In which direction does blood move in an VSD?

From left to right, due to high left ventricular pressure as compared to the right.


What single general effect does a VSD have?

Increases pulmonary blood flow


What are the 6 effects of a LARGE congenital VSD?

o Progressive obliteration of the pulmonary vasculature > pulmonary arterial pressure = systemic pressure \ shunt may be reduced/reversed > central cyanosis o Pulmonary hypertension o Pneumothorax o Breathlessness o Pulmonary oedema o Lung damage


What are the 2 moderate effects of a VSD?

Fatigue Dyspnoea with cardiac enlargement


What is the least common type of VSD?

A defect in the muscular part


What does an atrial septae defect allow?

Left to right shunts


What happen to people with an ASD above the age of 30?

* Above age of 30, there may be an increase in pulmonary vascular resistance > pulmonary hypertension > atrial arrhythmias esp. atrial fibrillation are common


What type of ASD is responsible for 75% of all ASD?

* Ostium secundum (foramen ovale) (75%) o Abnormally large opening in the atrial septum at the site of the foramen ovale and the ostium secundum


Why are both ASD and VSD's acyanotic?

Because oxygenated blood moves from left to right due to pressure differences - No deoxygenated blood in systemic circulation


What is the less common version of ASD?

An ostium primum ASD in the inferior portion of the septum (15%)


What is a patent foramen ovale and how common is it?

Foramen ovale remains open after birth, present in 20% of population


Why is a PFO not a true atrial septal defect?

Because higher left atrial pressure causes functional closure of the flap valve


Why can a PFO be clinically significant?

Can be the route by which a venous embolism reaches the systemic circulation if pressure on the right side of the heart increases even transiently


What is the effect of a left to right shunt?

* Left heart pressure > right heart pressure * Pulmonary resistance low so RV is easily compliant


What is a patent ductus arteriosus?

Vessel which sunts blood from the pulmonary artery to the aorta remains open after birth.


Which way does blood flow in a PDA?

From the aorta (high pressure) to athe plmonary artery (low pressure)


How sexy is Matt?

Very, very sexy. Like on a scale of 1-sexy, he's on at least a dashingly good looking. I mean, I'm talking George Clooney but with a staggeringly youthful disposition and better hair.

Edit : Oh, I was so naive in the days before I found my first grey hair. Another three appeared the other day. Me and George Clooney are becoming more similar every day. 


What can chronic left to right shunting result in?

Vascular remodelling of the pulmonary circulation and an increase in pulmonary resistance.


What happens if there is an increase in pulmonary resistance due to chronic left to right shunting? What is the name of the syndrome?

If pulmonary resistance increases beyone that of systemic circulation, the shunt will reverse direction as pressures on the right side of the heart increase. Eisenmenger syndrome


What is coarctation of the aorta?

A narrowing of the aortic lumen in the region of the ligamentum arteriosum (former ductus arteriosus)


What effect does coarctation of the aorta have on the heaart?

Increases afterload on left ventricle, which can lead to left ventricular hypertrophy


Why are the upper limbs and head usually unaffected by aortic coarctation?

Because the vessels to the head and upper limbs usually emerge proximal to the coarctation.


What happens if coarctation of aorta severe?

Infant presents with symptoms of heart failure shortly after birth


What are the symptoms of a mild coarctation of the aorta?

Weak, delayed femoral pulse and upper body hypertension


What is cyanosis?

Cyanosis: increased deoxygenated blood circulating in the body > blue appearance


What is the tetralogy of fallot?

A group of 4 lesions occurring together as the result of a single developmental defect which places the outflow portion of the interventricular septum too far in the anterior and cephalad directions.


What are the four features of the aptly named tertalogy of fallot?

Overriding Aorta VSD Pulmonary Stenosis Right Ventricular hypertrophy


What does pulmonary stenosis cause in tetralogy of fallot?

Persistence of the foetal right ventricular hypertrophy as the right ventricle must operate at a high pressure to pump blood through the pulmonary artery. - Right ventricular hypertrophy causes increased pressure and right to left shunting through VSD and overriding aorta - The causes mixing of deoxygenated blood with oxygenated blood - Cyanosis results


What does the severity of cyanosis depend on in the tetralogy of fallot?

The severity of pulmonary stenosis


What are the clinical features of the tetralogy of fallot

o Dyspnoea or fatigue o Cyanosis o Chronic hypoxaemia o Clubbing


What is tricuspid artesia?

Lack of development of the tricuspid valve, leaving no inlet to the right ventricle


What does a tricuspid atresia mean?

There must be a complete right to left shunt of all the blood returning to the right atrium (ASD or PFO) and a VSF or PA to allow blood flow to the lungs


What is transpostion of the great arteries?

Right ventricle connected to the aorta and left ventricle to the pulmonary trunk


What condition is commonly associated with transposition of the great arteries?

VSD in 50% of cases


How does transpostion of the great arteries occur in development?

Contruncal septum does not adopt spiral course


What is the path of blood when transposition of the great arteries has occured?

* \ deoxygenated blood from systemic veins > systemic circulation * & oxygenated blood from pulmonary veins > lungs


What is the chief clinical symptom when transposition of the great arteries occurs

Cyanotic blue baby Not compatible to life


How can transposition of the great arteries be fixed

A shunt must be maintained or created immediately following birth in order to allow two circulations to comminicate Most commonly the ductus arteriosus maintained, or ASD formed.


What is total anomalous pulmonary venous drainage

* All 4 pulmonary veins drain into vena cava or the right atrium Systemic and pulmonary venous blood mix in the right atrium


What is univentricular heart?

Atria drain into one ventricle


What is aortic stenosis caused by?

Senile calcification - inflammatory process


What happens in aortic stenosis?

* Leaflets now stiff > reducing systolic opening > increased LV pressure


What are the symptoms of aortic stenosis?

* Exercise induced angina, syncope & heart failure due to ischaemia of LV myocardium


What is aortic atresia?

* No LV outlet > impeded blood flow from LV * Only source of blood flow via PDA


What is pulmonary stenosis caused be?

* Usually due to a congenital lesion > rubella


What does pulmonary stenosis cause?

* Obstruction to RV systole > RV hypertrophy > RA hypertrophy * Fatigue, sycope and right heart failure


What is pulmonary artresia?

* No RV outlet * R to L shunt of entire venous system * Blood flow to lungs via PDA


Why would a patent ductus arteriosus form?

If duct is malformed, it will not close If they lack the mechanism to clsoe


What does a PDA cause?

Aorta to pulmonary shunt, increased venous return to left heart Left ventricular overload


What happens if shunt is too large in PDA?

o Left heart failure (in later adult life) o Pulmonary hypertension


Why does systemic hypertension result from coarctation of the aorta?

Decreased renal perfusion


What heart defect is shown in the picture?

Tetralogy of fallot


What does D show?

Narrowing of the pulmonary valve (stenosis)


What is C, and why does it come about?

Thickening of right ventricle wall, which hypertrophies due to higher pressure required to pump blood through pulmonary stensosis


What does A show?

Displacement of aorta over ventricular septal defect


What does B show?

Ventricular septal defect - opening between the left and right ventricles


Give the incidence/100,000 births for the following 

Atrial septal defect

Patent Foramen Ovale

Ventricular septal defect






Give the incidence per 100,000 births for the following

Patent ductus arteriosus

Coarctation of the aorta

Tertalogy of Fallot





Give the incidence per 100,000 births for the following

Transposition of the great arteries

Hypoplastic left heart





What is hypoplastic left heart?

Left ventricle fails to develop properly, with a PFO or ASD also present, with blood supply to systemic circulation via PDA.