Cardio - Phys/Ana/Emb Flashcards Preview

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Flashcards in Cardio - Phys/Ana/Emb Deck (94):
1

Vitelline veins

Portal system veins

2

Cardinal veins

systemic circulation veins

3

Truncus arteriosus

Ascending aorta and pulmonary trunk

4

Bulbus cordis

Smooth parts (outflow tract) of left and right ventricles

5

Primitive atrium

trabeculated part of L/R atria

6

Primitive ventricle

trabeculated part of L/R ventricles

7

Primitive pulmonary vein

smooth part of left atrium

8

Left horn of sinus venosus

Coronary sinus

9

Right horn of sinus venosus

Smooth part of right atrium (sinus venarum)

10

Right common cardinal vein and right anterior cardinal vein

SVC

11

When does heart start beating?

4 weeks (first functional organ)

12

Atrial septation

Septum primum --> Foramen primum --> Foramen secundum --->Septum secundum -->foramen ovale

13

Outflow tract from?

Neural crest migration + endocardial cushion migration

14

All valve origins?

Endocardial cushions

15

Fetal erythropoiesis

Young Liver Synthesizes Blood
- Yolk sac (3-8wks)
- Liver (6wks - birth)
- Spleen (10-28wks)
- Bone marrow (18wks - adult)

16

HbF unique?

Less avid binding 2,3-BPG

17

Umbilical vein O2

PO2 = 30mmHg
80% saturation

18

Ductus venosus

Shunts blood from umbilical vein into IVC
- becomes ligamentum venosum

19

Allantois-->Urachus

Median umbilical ligament

20

Ductus arteriosus becomes

Ligamentum arteriosum

21

Foramen ovale becomes

Fossa ovale

22

Umbilical arteries

Medial umbilical ligaments

23

Umbilical vein

Ligamentum teres hepatis contained in falciform ligament

24

SA and AV node blood supply

SA - RCA
AV - branch of posterior descending artery (RCA or LCA)

25

LCX

- lateral and posterior walls of LV
- anterolateral papillary muscle

26

LAD

- ant. 2/3 of IV septum
- anterolateral papillary muscle
- ant surface of LV

27

PDA

- post 1/3 of IV septum
- post walls of ventricles
- posteromedial papillary muscle

28

CO =

= SV x HR

= rate of O2 consumption/(arterial O2 content - venous O2 content)

29

MAP =

CO x TPR

30

Pulse pressure and SV/arterial compliance

PP is proportional to SV
PP is inversely proportional to arterial compliance

31

Increased Pulse Pressure

Hyperthyroidism, aortic regurgitation, aortic stiffening (isolated systolic HT in elderly), obstructive sleep apnea (increased sympathetic tone), exercise (transient)

32

Decreased Pulse Pressure

Aortic stenosis, cardiogenic shock, cardiac tamponade, advanced heart failure (HF)

33

Increased contractility

- Catecholamine (Increase activity of Ca2+ pump in SR)
- Increased intracellular Ca
- Decreased extracellular Na
- Digitalis

34

Decreased contractility

- B1 blockage
- HF w/systolic dysfunction
- acidosis
- hypoxia/hypercapnia
- Non-dihydropyridine Ca channel blockers

35

Increased diameter of ventricle

Increased wall tension --> increased myocardial O2 demand

36

ACEI/ARBs - preload and afterload?

decrease both

37

Normal EF

>55%

38

Phospholamban

Dephorphorylated phospholamban binds SERCA-2 (SR Ca-ATPase) and decreases affinity for Ca2+
- membrane protein
- decreased rate of muscle relaxation and contractility (decreased HR and SV)
- phosphorylated by PKA (adrenergic)

39

Organ removal (eg. nephrectomy)...

Increases TPR and decreases CO

40

Driving pressure =

Q x R

Q=flow velocity x cross sectional area
R=8nl/3.14r^4

41

TPR on venous return

(+) TPR - decreased
(-) TPR - increased

42

TPR (increase and decrease)

Increased by: vassopressors (constrictors)
Decreased by: exercise, AV shunt

43

Period of highest O2 consumption (LV cycle)

Isovolumetric contraction

44

Jugular venous pulse

a wave - atrial contraction (absent in a-fib)
c wave - RV contraction
x descent - atrial relax + downward tricuspid displacement (absent in tricuspid regurg)
v wave - atrial filling against closed tricuspid
y descent - RA empties into RV

45

Constrictive pericarditis

rapid y descent that is deeper and steeper w/ inspiration

46

S1

loudest at mitral area

47

S2

loudest at left upper sternal border

48

S3

- @ early diastole
- increased filling pressure (mitral regurg, HF)
- more common in dilated ventricles
- normal in kids and pregos'
- heard best at apex while lying lateral decubitus @ end-expiration

49

S4

- @ late diastole
- "atrial kick"
- high atrial pressure
- assoc. w/ ventricular hypertrophy (LA must push against stiff LV wall)
- heard best at apex while lying lateral decubitus @ end-expiration

50

Wide splitting

Delayed RV emptying (ex. pulmonic stenosis, right bundle branch block)

51

Fixed splitting

ASD

52

Paradoxical splitting

Delayed aortic valve closure (ex. aortic stenosis, left bundle branch block)
- A2 after P2, decreased gap with inspiration

53

Left sternal border

Diastolic murmor
- aortic regurg
- pulmonic regurg

Systolic murmor
- hypertrophic cardiomyopathy

54

VSD murmor

Pansystolic @ tricuspid area

55

ASD presentation

- pulmonary flow murmur (pulmonary valve)
- diastolic rumble (tricuspid valve)

(later progresses to louder diastolic murmur of pulmonic regurgitation from pulmonary a. dilation)

56

Bedside maneuver: Inspiration (venous return)

Increased intensity of right heart sounds

57

Bedside maneuver: Hand grip (afterload)

- Increased intensity of MR, AR, VSD murmurs
- Decreased hypertrophic cardiomyopathy murmurs
- MVP: later onset of click/murmur

58

Bedside maneuver: Valsalva (phase II), standing up
(preload decrease)

- Decreased intensity of most murmurs (including AS)
- Increased intensity of hypertrophic cardiomyopathy murmor (LVOT obstruction)
- MVP: early onset of click/murmur

59

Bedside maneuver: Rapid squatting (preload increase)

- Decreased intensity of hypertrophic cardiomyopathy murmur
- Increased intensity of AS murmor
- MVP: later onset of click/murmur

60

Pulsus parvus et tardus

pulses are weak w/ delayed peak
- aortic stenosis

61

Mitral regurg

- Radiates towards axilla
- often d/t MI, MVP, LV dilation

62

Most frequent valvular lesion

MVP

63

Best indicator of AR severity

Presence of S3 (high rate of ventricular filling)

64

AR auscultation

Best heard @ left sternal border b/t 3/4, while patient sitting, leaning forward and at end expiration

65

Ortner Syndrome

LA dilation impinges on left recurrent laryngeal n.
- can be d/t mitral stenosis

66

Skeletal vs. cardiac muscle Ca release from SR

- Ryanodine receptor linked L-type Ca channel
- L-type Ca channel causes Ca influx inducing Ca release

67

Conduction speed

Purkinje fibers > atrial myocytes > ventricular myocytes > AV node

68

PR interval

less than 200 msec normally

69

QRS interval

less than 120 msec normally

70

J point

Junction b/t end of QRS and start of ST segment

71

U wave

Caused by hypokalemia or bradycardia

72

AV node delay

100 msec

73

Torsades de pointes causes

1) Drugs (ABCDE)
- AntiArrhythmics (class IA, III)
- AntiBiotics (eg. macrolides)
- Anti"C"ychotics (eg. haloperidol)
- AntiDepressants (eg. TCA)
- AntiEmetics (eg. ondansetron)
2) Hypokalemia
3) Hypomagnesia
4) Long QT syndrome

74

Torsades de pointes Rx

Magnesium sulfate

75

Romano-Ward syndrome

- Congenital long QT syndrome (AD)
- NO deafness

76

Jervell and Lange-Nielsen syndrome

- Congenital long QT syndrome (AR)
- sensorineural deafness

77

Brugada syndrome

- ECG pattern of pseudo-right bundle branch block and ST elevations in V1-V3
- AD more common in asian males
- Increased risk of ventricular tachyarrhythmias and SCD

Rx: Prevent SCD w/ implantable cardioverter-defib

78

Delta wave

Wolff-Parkinson-White syndrome
- associated w/ widened QRS and shortened PR

79

Binge drinking "Holliday Heart"

A-fib

80

PR interval >200 msec

1st degree AV block

81

Wenckebach

Second degree heart block: Mobitz type 1

82

Lyme disease can cause...

complete (3rd degree) heart block

83

ANP

- acts via cGMP
- from atrial myocytes
- vasodilation and decreased Na reabsorption in CT
- Renal aff. dilation and eff. constriction (aldosterone escape)

84

BNP

- ventricular myocytes
- longer half-life than ANP
- GOOD negative predictive value for Dx HF

85

Nesiritide

Recombinant BNF for treating HF

86

Aortic arch and carotid sinus nerve relay

AA - vagus n --> solitary nucleus of medulla
CS - glossopharyngeal n -->solitary nucleus of medulla

87

Cushing reaction

Triad of hypertension, bradycardia, respiratory depression
- Increased ICP constricts arterioles --> decrease pH --> sympathetic reflex --> HYPERTENSION --> baroreflex causes BRADYCARDIA. Pressure on brainstem causes RESP. DEP.

88

Heart pressures

RA: less than 5
RV: 25/5
PA: 25/10
PCWP: less than 12
LA: less than 12
LV: 130/10
A: 130/90

89

Mitral stenosis PCWP

PCWP > LV

90

Hormone permissiveness

When one hormone allows another to exert its maximal effect (the aiding hormone has no intrinsic effect)

91

Exercise on TPR

DECREAED

92

Most deoxygenated blood in body

Cardiac venous blood
(myocardium has HIGH O2 extraction (60-75%)

93

Ach, Bradykinin, shear stress -->

Argine + O2 -----eNOS----->NO + citrulline

94

Sudden deceleration ruptures the....

Aortic isthmus