Development of Heart

Question 1

No. of heart defects

Answer 1

1:200 babies

Question 2

Cyanotic Heart lesions

Answer 2

Right to Left
Mix of O2 poor systemic blood with O2 rich pulmonary blood
Septal defects, patent ductus arteriosus

Question 3

Acyanotic Heart lesions

Answer 3

Left to Right
Narrowed valves or vessels that greatly increase the workload of the heart
Generally structural problems
Coarctation of Aorta

Question 4

Heartbeat Detected first

Answer 4

day 22

Question 5

Heart develops from this tissue

Answer 5

Cardiogenic mesoderm

Question 6

Primitive heart tube formation

Answer 6

Day 21

Question 7

Sinus venosus becomes

Answer 7

Right atrium, IVC + coronary sinus

Question 8

Primitive atria become

Answer 8

R + L auricles, and left atrium

Question 9

Atrioventricular sulcus divides

Answer 9

Atria from primitive ventricle

Question 10

Primitive ventricle becomes

Answer 10

Left Ventricle

Question 11

Interventricular sulcus divides

Answer 11

Primitive ventricle from bulbus cordis

Question 12

Bulbus cordis 1/3 becomes

Answer 12

Muscular RV

Question 13

Bulbus cordis 2/3 becomes

Answer 13

Smooth outflow of RV and LV

Question 14

Truncus arteriosus becomes

Answer 14

Asc Aorta

Pulmonary trunk

Question 15

Situs invertus occurrence

Answer 15

1:7000

Question 16

Endocardial cushions derived from

Answer 16

Neural crest

Question 17

Septum primum appearance

Answer 17

day 28

Question 18

Ductus arteriosus

Answer 18

Shunts blood pulmonary trunk –> ascending aorta (lungs bypassed)

Question 19

Ductus arteriosus reasons

Answer 19

Protects lungs against circulatory overload
Allows RV to strengthen
High pulmonary vascular resistance
Low Pulmonary blood flow
Moderately saturated blood

Question 20

Ductus venosus

Answer 20

Shunts blood from umbilical vein to IVC
Bypasses liver
Flow regulated via sphincter

Question 21

Ductus venosus reasons

Answer 21

Conducts highly oxygenated blood

Question 22

Foramen ovale

Answer 22

Bypasses pulmonary circulation

Shunts highly oxygenated blood RA –> LA

Question 23

Umbilical vein becomes

Answer 23

Ligamentum Teres

Question 24

Mesentry becomes

Answer 24

Falciform ligament

Question 25

Ductus venosus becomes

Answer 25

Ligamentum venosum of liver

Question 26

Foramen ovale becomes

Answer 26

Fossa ovalis

Question 27

Foramen Ovale Change mechanism

Answer 27

Decreased flow from placenta and IVC --> lower pressure in RA Decreased pulmonary vascular resistance secondary to lung expansion Increase pulmonary blood flow Higher LA pressure compared to IVC Closure due to higher LA pressure than RA

Question 28

Ductus arteriosus becomes

Answer 28

Ligamentum arteriosum

Question 29

Ductus arteriosum change mechanism

Answer 29

Closed by increased paO2 | Closure mediated by bradykinin

Question 30

What may reopen Ductus arteriosus

Answer 30

Prostaglandin E2

Question 31

Tetralogy of Fallot

Answer 31

Overriding aorta arising directly above septal defect RV hypertrophy Ventricular Septal defect Narrow RV flow

Question 32

Cyanotic Heart lesions

Answer 32

Tetralogy of Fallot Truncus Arteriosus Transposition of the Great Vessels

Question 33

Persistent Truncus Arteriosus

Answer 33

Single artery comes from heart- supplies both aorta + pulmonary artery Large VSD allows mixing of R + L ventricular blood

Question 34

Transposition of the Great Vessels

Answer 34

Aorta + pulmonary artery switched | blue baby

Question 35

Acyanotic Heart Diseases

Answer 35

Atrial Septal Defects Ventricular Septal Defects Patent Ductus Arteriosus

Question 36

Atrial Septal Defect

Answer 36

Hole between 2 atria 7:10000 births 2:1 prevalence F:M Asymptomatic first 3 decades of life

Question 37

Ventricular Septal Defect

Answer 37

25% congenital birth defects Many close spontaneously- 30-50% 90% in membranous septum- L->R of blood + pulmonary hypertension 10% in muscular septum- L->R of blood

Question 38

Patent Ductus Arteriosus

Answer 38

Connection between descending aorta to main pulmonary trunk | Near origin of left subclavian

Question 39

Coarctation of Aorta

Answer 39

Constriction may be above or below ductus arteriosus Pre-ductal= allow blood flow Post-ductal= Collateral circulation must be established

Question 40

Coarctation of Aorta diagnosis

Answer 40

Systematic hypertension Secondary LVH with heart failure Decreased lower extremity pulses

Question 41

Coarctation of aorta treatment

Answer 41

Balloon angioplasty

Question 42

Patent ductus arteriosus diagnosis

Answer 42

Prostaglandin inhibitor- ibuprofen | Clip above 3 months (surgery)