Cardiology Flashcards
In developing fetus, pressure in R heart > pressure in L heart. Why?
Lungs (and thus pulmonary circulation) are not fully functional. This creates increased vascular resistance in pulmonary arterial circulation, and increased pressure in R heart (which supplies pulmonary arterial circulation).
Fetal erythropoiesis occurs in which 4 sites?
Yolk sac (3-8 wks)Liver (6 wks - birth)Spleen (10-28 wks)Bone marrow (18 wks - adult)”Young Liver Synthesizes Blood”
Primary site for O2 exchange in fetus?
Chorionic villi (Umbilical vein is derived from villus vessels)
Chorionic villi is derived from ___ (maternal/fetal) tissue?
Fetal tissue
Fetal circulatory shunt:Ductus venosus = ?
Oxygenated blood conducted via umbilical vein bypasses liver (hepatic circulation) via ductus venosus directly into IVC, which drains into RA
RV - Right acute/marginal artery LV anterior wall - LAD (LCA) LV posterior wall - PDA LV lateral wall - LCX (LCA) LV inferior wall - RCA LV anteroseptal wall - proximal LAD (LCA) LV anterolateral wall - LCX (LCA)
Anterior 2/3 of IV septum - LAD (LCA)
Posterior 1/3 of IV septum - PDA
Anterior (anterolateral) papillary muscle in LV
- LAD (LCA)
Posterior (posteromedial) papillary muscle in LV - PDA
b
Right-dominant coronary circulation?
Left-dominant coronary circulation?
Co-dominant coronary circulation?
PDA arises from RCA (80%)
PDA arises from LCX branch of LCA (10%)
PDA arises from both RCA and LCX branch of LCA (10%)
In fetal circulation, most blood that enters RA via SVC is conducted where?
SVC –> RA –> RV –> pulmonary artery –> PDA –> descending aorta Blood is conducted/shunted through patent ductus arteriosus into aorta
During fetal development, what maintains patency of ductus arteriosus?
PGE2, a vasodilator synthesized by placenta
In fetal circulation, most blood that enters RA via IVC is conducted where?
IVC –> RA –> LA –> LV –> ascending aortaOxygenated blood from umbilical vein enters RA via IVC and is conducted/shunted through patent foramen ovale to LA. Oxygenated blood is most important to enter ascending aorta to provide blood with highest O2 tension to head/neck.
Why is blood conducted from RV shunted away from lungs and instead conducted through ductus arteriosus?
Low PaO2 –> chronic vasoconstriction of pulmonary arteries –> fetal pulmonary arteries are HYPERTROPHIED (high fetal pulmonary arterial resistance)When baby is born, 1st breath –> increases PaO2 –> decreases pulmonary arterial resistance
What 2 physiologic changes occur at birth that close ductus arteriosus?
1st breath –> increases PaO2Separation of placenta –> decreases PGE2
Describe physiologic changes that occur with 1st breath leading to closure of foramen ovale.
1st breath –> increases PaO2 –> decreases pulmonary arterial resistance –> blood flows through pulmonary circulation and drains into LA –> increases pressure in LA –> pressure LA > pressure RA –> functionally closes foramen ovale
Drug administered to close a patent ductus arteriosus?
Indomethacin
Drug administered to maintain a patent ductus arteriosus?
PGE2
EMBRYONIC STRUCTURE:Umbilical veinPost-natal derivative?
Ligamentum teres hepatis (within falciform ligament)
EMBRYONIC STRUCTURE:Umbilical arteriesPost-natal derivative?
Medial umbilical ligaments (Not to be confused with MEDIAN umbilical ligament, a derivative of urachus)
EMBRYONIC STRUCTURE:Ductus arteriosusPost-natal derivative?
Ligamentum arteriosum
EMBRYONIC STRUCTURE:Ductus venosusPost-natal derivative?
Ligamentum venosum
EMBRYONIC STRUCTURE:Foramen ovalePost-natal derivative?
Fossa ovalis
EMBRYONIC STRUCTURE:NotochordPost-natal derivative?
Nucleus polposus of IV disc
EMBRYONIC STRUCTURE:Urachus (allantois)Post-natal derivative?
Median umbilical ligament(Not to me confused with MEDIAL umbilical ligaments, derivatives of umbilical arteries)
Anterior surface of heart is formed by?
R ventricle
Another name for anterior surface of heart?
Sternocostal surface
Inferior surface of heart is formed by?
L and R ventricles
Another name for inferior surface of heart?
Diaphragmatic surface
Posterior surface of heart is formed by?
L atrium
Apex of heart is formed by?
L ventricle
Penetrating injury at L sternal border, 2nd intercostal space = injury to?
Pulmonary trunk
Penetrating injury at R sternal border, 2nd intercostal space = injury to?
SVC
Penetrating injury at L sternal border, 4th intercostal space = injury to?
R ventricle
Penetrating injury at L midclavicular line, 5th intercostal space = injury to?
L lung5th intercostal space, midclavicular line = location of heart apex (L ventricle), but covered by L lung
Right coronary artery (RCA) - 4 branches?
SA nodal arteryAV nodal arteryAcute marginal arteryPosterior descending artery (PDA) - in right-dominant (80%) or co-dominant (10%) populations
Left coronary artery (LCA) - 3 branches?
Left anterior descending artery (LAD)Left circumflex artery (LCX)Posterior descending artery (PDA) - in left-dominant (10%) or co-dominant (10%) populations
SA node and AV node supplied by?
SA nodal and AV nodal branches of RCA
R ventricle supplied by?
Acute marginal branch of RCA
L atrium supplied by?
LCX branch of LCA
Anterior wall of LV supplied by?
LAD branch of LCA
Posterior wall of LV supplied by?
PDA
Lateral wall of LV supplied by?
LCX branch of LCA
Anterior 2/3 of IV septum supplied by?
LAD branch of LCA
Posterior 1/3 of IV septum supplied by?
PDA
Anterior papillary muscle in LV supplied by?
LAD branch of LCA
Posterior papillary muscle in LV supplied by?
RCA
Right-dominant coronary circulation?
PDA arises from RCA (80%)
Left-dominant coronary circulation?
PDA arises from LCX branch of LCA (10%)
Co-dominant coronary circulation?
PDA arises from both RCA and LCX branch of LCA (10%)
1st MC site for coronary artery thrombosis?
LAD branch of LCA
2nd MC site for coronary artery thrombosis?3rd most common site?
2nd - RCA3rd - LCX branch of LCA
Coronary arteries fill during which aspect of cardiac cycle?
Diastole
Tachycardia predisposes to myocardial ischemia because?
Tachycardia (> 180 bpm) decreases diastole and filling time –> decreases filling of coronary arteries –> leads to myocardial ischemia
How does L atrial enlargement cause dysphagia?
Compression of esophagus
How does L atrial enlargement cause hoarseness?
Compression of left recurrent laryngeal nerve, a branch of vagus nerve
Positioning TEE probe anteriorly allows for visualization of?
L atrium, atrial septum, and mitral valve
Positioning TEE probe posteriorly allows for visualization of?
Descending aorta
Inferior wall of LV supplied by?
PDA
