Z-Congenital Heart Disease

Front 1

Two types of atrial septal defects:

Back 1

1. fossa ovalis or secudum type
2. ostium primum type

Front 2

Describe what is going on in an atrial septal defect:

Back 2

The pressure in the L atrium is slightly higher than that of the R and the compliance of the R ventricle is far greater than the L. Therefore, a shunt at the atrial level will produce volume hypertrophy of the R atrium and R ventricle with increased pulmonary flow and hemodynamic changes in the tricuspid and pulmonic valves.

Front 3

Where is the most common location of a ventricular septal defect?

Back 3

Most commonly VSD's occur beneath the aortic valve, confluent in part with the membranous septum. These are called subaortic VSD's and they are in part membranous and in part perimembranous.

Front 4

Describe the anatomical changes that occur with a VSD:

Back 4

Hypertrophy of the right ventricle occurs along with enlargement of the pulmonic orifice, hemodynamic changes of the tricuspid and pulmonic valves, volume hypertrophy of the L atrium and ventricles with enlargment of the mitral valve and hemodynamic changes in the mitral and aortic valves.

Front 5

Many small defects in the ventricular septum close spontaneously in the first years of life. However these people are still predisposed to what?

Back 5

Infective endocarditis in the closing defect

Front 6

What can a large VSD cause?

Back 6

In addition to hypertrophy of the RV, LA, and LV, the pressure of the LV may be transmitted to the RV and cause pressure hypertrophy of the R ventricle.

Front 7

In a patent ductus arteriousus there is a left to right shunt that causes what changes to the chambers of the heart?

Back 7

Left atrium and ventricle hypertrophy

Front 8

All left to right shunts cause increased pulmonary flow. Discuss how it is compensated for sometimes but others it gets worse:

Back 8

Compensated for: L to R shunts causes increased pulm flow but the large distensability of the pulmonary vascular tree can accomodate with increasing the pressure in the pulmonary circuit.

However, pulmonary hypertension may develop for one of three reasons:
1. flow increases to much
2. vasoconstriction of pul vasculature is induced
3. secondary path changes in the intima and media of the arteries of the lungs restrict blood flow

Front 9

What is the Eisenmenger complex?

Back 9

A complex that involves a reversal of the shunt from left-to-right to right-to-left. The path effects of pulmonary hypertension of the heart following a left to right shunt are related to increase in pressure of the right side with or without decreased flow to the left side fo the heart. This will result in pressure hypertrophy on the right side with decrease in the previously present volume hypertrophy of the left side. This may produce volume atrophy on the left side.

Front 10

What percentage obstruction must occur to be declared an obstruction?

Back 10

greater than 65% obstructed

Front 11

Describe a pulmonary stenosis:

Back 11

The pulmonic valve usually consists of a diaphagm-like structure with an attempted formation of cusps with a central small opening. This causes pressure hypertrophy of the right ventricle that is often associated with post stenotic dilatiation of the pulmonary trunk and hemodynamic changes in the tricuspid valve.

Front 12

Describe the morphological changes in a heart with aortic stenosis:

Back 12

In AS there usually is L ventricular hypertrophy with a smaller than usualy L ventricle. Often the left atrium is hypertrophied with hemodynamic changes of the mitral valve.

Front 13

What is coarctation of the aorta?

Back 13

When there is narrowing of the transverse arch in the region of the isthmus. The isthmus is the segment between the origin of the left subclavian a and ductus or ligamentum arterious.

Front 14

Explain what congenital heart disease can develop collateral anastomosis.

Back 14

In the event of coarctation of the aorta, this can cause pressure hypertrophy of the L ventricle and L atria. There is hypertension proximal and hypotension distal to the area of narrowing. Collateral anastomoses may develop. bypassing the area of narrowing between the proximal and distal portions of the aorta by way of the subclavian, dorsal scapular, internal mammary, and intercostal arteries.

Front 15

What four things does Tetralogy of Fallow consist of?

Back 15

1. infundibular pulmonary stenosis
2. right ventricular hypertrophy
3. ventricular septal defect
4. overriding aorta

Front 16

Infundibular pulmonary obstruction is the most significant part of the disease of Tetralogy of Fallow - explain what is going on:

Back 16

The outflow tract of the R ventricle is called the infundibulum which consists of septal and parietal groups of muscle bands. The muscles may be abnormally orientated and markedly hypertrophied resulting in infundibular pulmonary obstruction. The ventricular septal defect is a U shaped deformity of the ventricular septum confluent with the aortic valve. Thus, the aorta overrides the defect emerging from both the ventricular chambers.

Front 17

There are two types of Tetralogy of Fallow - cyanotic and acyanotic: Describe cyanotic -

Back 17

Cyanotic:
Here there is pressure hypertrophy of the right atrium and right ventricle with significant infundibular pulmonary obstruction. The left atrium and ventricle have a tendency to be smaller than normal. The right ventricle is contracting against systemic and infundibular resistance, decreased pulmonary flow, and predominant R to L shunt at the ventricular level.

Front 18

There are two types of Tetralogy of Fallow - cyanotic and acyanotic: Describe acyanotic -

Back 18

In acyanotic there is pressure and vol hypertrophy of the R ventricle, pressure hypertrophy of the R atrium, vol hypertrop of L atrium and vent, and enlargement of the mitral and aortic orifices. Here we are dealing with a L to R SHUNT at the ventricular level with increased pulmonary flow and increased volume to the left side of the heart.