Congenital Heart Disease + other abnormalities Flashcards
Cranial to Caudal heart tube dilatations
Bulbus cordis
Ventricle
Atrium
Sinus venosus
Septation of the heart
Looping of the heart allows straight heart tube to form a more complex structure
Most cardiac looping occurs during fourth week + completes during 5th week
Cardiac embryology
Clusters of angiogenic cells- mesodermal cardiogenic plate
When do R/L endocardial tubes fuse to single cardiac tube
By day 21
When does heart beat
By day 23
Atrial, ventricular and outflow septation
Day 28
Foetal circulation Anatomical connections
Foramen ovale
Ductus arteriosus
Ductus venosus
Foetal circulation
High resistance pulmonary circulation
Low resistance systemic circulation
Cyanotic CHD
Patient blue
Affected by Hb level
Lung disease (e.g. pneumonia) may cause cyanosis
Acyanotic CHD
Patient pink
Cyanotic CHD Hb
Blue colours produced by amounts of deoxygenated Hb, not percentage saturation (SaO2)
Cyanosis = deoxygenated Hb>50g/l in capillaries
Cyanosis= >34g/l in arterial blood
Cyanosis in capillaries
Deoxygenated Hb > 50g/l
Cyanosis in arteries
Deoxygenated Hb >34g/l
Cyanosis congenital heart disease gas exchange
Normal alveolar gas exchange Normal CO2 No dyspnoea Normal pulmonary venous saturations Results from "shunting" of deoxygenated blood from R --> L side of circulation
Cyanosis lung disease gas exchange
Impaired alveolar gas exchange CO2 may be increased Tachypnoea + recession Reduced pulmonary venous saturations Results from O2 diffusion problems or ventilation-perfusion mismatch within lung