Cardiology Flashcards Preview

USMLE Step 1. > Cardiology > Flashcards

Flashcards in Cardiology Deck (116):
1

Truncus arteriosus gives rise to:

Ascending aorta and pulmonary trunk

2

Bulbous cordis gives rise to:

Smooth parts (outflow tract) of L and R Ventricles

3

Primitive atrium gives rise to:

Trabeculated part of L and R atria

4

Primitive ventricle gives rise to:

Trabeculated part of L and R ventricles

5

Primitive pulmonary vein gives rise to:

Smooth part of the L Atrium

6

Left horn of Sinus Venosus gives rise to:

Coronary Sinus

7

Right horn of Sinus Venosus gives rise to:

Smooth part of R A Atrium (Sinus Venarum)

8

Right common cardinal vein and Right anterior cardinal vein give rise to:

Superior Vena Cava (SVC)

9

When does the heart start beating?

Week 4 - first functional organ in vertebrate embryos

10

Kartagener Syndrome

Defect in L-R dynein (involved in L/R asymmetry) can lead to dextrocardia as seen in this disease.

Messes up embryological cardiac looping

11

Where does VSD commonly occur?

in the membranous septum

12

Patent Foramen Ovale

caused by failure of septum primum and septum secundum to fuse after birth

Most are left untreated

Can lead to paradoxical emboli (venous thromboemboli that enter systemic ARTERIAL circulation) - similar to those resulting from ASD

13

What are 3 common conotruncal abnormalities?

Transposition of the great vessels
Tetralogy of Fallot
Persistent truncus arteriosus

14

Sites of erythropoiesis

Yolk Sac (3-8 wks)
Liver (6 wks - birth)
Spleen (10-28 wks)
Bone marrow (18 wks to adult)

Only bone marrow is doing this ish after birth

15

What are 3 important shunts in fetal blood flow?

Ductus venosus
Foramen ovale
Ductus arteriosus

16

Allantois/urachus becomes...

Meidan umbilical ligament (urachus is part of allantoic duct btw bladder and umbilicus)

17

Ductus arteriosus becomes...

Ligamentum arteriosum

18

Ductus venosus becomes...

Ligamentum venosum

19

Foramen ovale becomes...

Fossa ovalis

20

Notochord becomes...

Nucleus pulposus

21

Umbilical arteries become...

Medial umbilical ligaments

22

Umbilical vein becomes...

Ligamentum teres hepatis (contained in falciform ligament)

23

What the most common coronary artery blockage?

LAD

24

Left coronary artery branches

LCX - supplies lateral and posterior walls of LV, anterolateral papillary muscle

Left Marginal (Obtuse) Artery

LAD - supplies anterior 2/3 of interventricular septum, anterolateral papillary muscle, and anterior surface of LV

PDA (rarely, but can happen) - If it does happen it would be a branch of LCX

25

Right coronary artery branches

Right marginal (Obtuse) Artery - supplies RV

PDA (usually) - supplies posterior 1/3 of interventricular septum, posterior walls of ventricles, and posteromedial papillary muscle.

RCA also supplies AV node most of the time

26

Cardiac output formula

CO = SV x HR

27

Fick's principle

CO = [rate of O2 consumption]/[arterial O2 content - venous O2 content]

28

Mean arterial pressure (MAP) formula

MAP = 2/3(diastolic) + 1/3(systolic)

MAP = CO x TPR

29

Pulse pressure formula

PP = systolic - diastolic

30

Stroke volume formula

SV = EDV - ESV

SV = CO/HR

31

Wall Tension formula (Laplace's Law)

Wall tension = (pressure x radius)/(2 x wall thickness)

32

Ejection Fraction formula

EF = SV/EDV = (EDV=ESV)/EDV

33

Resistance, Pressure, Flow formulas

Change in P = QR

R = P/Q = 8NL/Pi r^4

TR in series = R1 + R2..

TR in parallel: 1/TR = 1/R1 + 1/R2

34

Conditions that exhibit wide splitting of heart sounds

Pulmonic stenosis
R Bundle branch block

Conditions that delay RV emptying

35

Conditions that exhibit fixed splitting of heart sounds

ASD

36

Conditions that exhibit paradoxical splitting of heart sounds

Aortic stenosis
L Bundle branch block

Conditions that delay aortic valve closure

37

What is best heard over Aortic area?

Systolic murmur:
Aortic Stenosis
Flow murmur
Aortic valve sclerosis

38

What is best heard of left sternal border?

Diastolic murmur:
Aortic regurgitation
Pulmonic regurgitation

Systolic murmur:
Hypertrophic cardiomyopathy

39

What is best heard over left infraclavicular region?

Continuous murmur:
PDA

40

What is best heard over Pulmonic Area?

Systolic ejection murmur:
Pulmonic stenosis
Flow murmur (physiologic murmur)

41

What is best heard over Tricuspid Area?

Pansystolic murmur:
Tricuspid regurgitation
VSD

Diastolic murmur:
Tricuspid stenosis
ASD

42

What is best heard over Mitral Area?

Systolic murmur:
Mitral regurgitation

Diastolic murmur:
Mitral stenosis

43

What murmurs are systolic?

Aortic Stenosis
Pulmonic Stenosis
Mitral Regurgitation
Tricuspid Regurgitation
VSD
MVP

44

What murmurs are diastolic?

Aortic Regurgitation
Pulmonic Regurgitation
Mitral Stenosis
Tricuspid Stenosis

45

Aortic stenosis findings

Crescendo-decrescendo systolic ejection murmur.

LV >> aortic pressure during systole

Loudest at heart base - radiates to carotids. "Pulsus parvus et tardus" - pulses are weak with a delayed peak.

Can lead to syncope, angina and dyspnea on exertion (SAD)

Often due to age-related calcification or early-onset calcification of bicuspid aortic valve.

46

Mitral/Tricuspid regurgitation findings

Holosystolic, high-pitched "blowing murmur"

Mitral - loudest at apex and radiates to axilla. MR is often due to ischemic heart disease (post MI), MVP, LV dilation

Tri - loudest at tricuspid area and radiates to right sternal border. TR commonly caused by RV dilation

Rheumatic fever and infective endocarditis can cause either MR or TR

47

MVP findings

Late systolic crescendo murmur with midsystolic click (MC; due to sudden tensing of chordae tendineae).

Most frequent valvular lesion.

Best heard over apex. Loudest just before S2.

Usually benign.

Can predispose to infective endocarditis. Can be caused by myxomatous degeneration ( primary or secondary to connective tissue disease such as Marfan or Ehlers-Danlos), rheumatic fever, chordae rupture.

48

VSD findings on auscultation

Holosystolic, harsh-sounding murmur. Loudest at tricuspid area.

49

Aortic regurgitation findings

High-pitched blowing early diastolic decrescendo murmur.

Long diastolic murmur and signs of hyperdynamic pulse when severe and chronic. Often due to aortic root dilation, bicuspid aortic valve, endocarditis, RF. Progresses to left HF.

50

Mitral stenosis findings

Follows opening snap (OS - due to abrupt halt in leaflet motion in diastole, after rapid opening due to fusion at leaflet tips).

Delayed rumbling late diastolic murmur (smaller interval between S2 and OS correlates with increased severity).

LA >> LV pressure during diastole. Often occurs secondary to RF. Chronic MS can result in LA dilation

51

PDA findings on auscultation

Continuous machine-like murmur. Loudest at S2. Often due to congenital rubella or prematurity.

Best heard at left infraclavicular area

52

P wave

atrial depolarization

Atrial repolarization is masked by QRS

53

PR interval

time from start of atrial depolarization (start of P wave) to start of ventricular depolarization (start of QRS).

Normal = less than 200 ms

54

QRS complex

Ventricular depolarization

Normally less than 120 ms

55

QT interval

ventricular depolarization, mechanical contraction of the ventricles. ventricular repolarization. From start of QRS to end of T.

56

T wave

ventricular repolarization

T wave inversion may indicated recent MI

57

J point

junction between end of QRS complex and start of ST segment

58

ST segment

isoelectric, ventricles depolarized

59

U wave

caused by hypokalemia, bradycardia

60

Torsades de pointes

Polymorphic ventricular tachycardia, characterized by shifting sinusoidal waveforms on ECG; can progress to VFib.

Long QT interval predisposes to torsade de pointes. Caused by drugs, decreased K, decreased Mg, other abnormalities.

Tx = magnesium sulfate

61

Congenital long QT syndrome

Inherited disorder of myocardial repolarization, typically due to ion channel defects.

Higher risk of sudden cardiac death (SCD) due to torsades de pointes. Includes:

1) Romano-Ward Syndrome: autosomal dominant, pure cardiac phenotype (no deafness)

2) Jervell and Lange-Nielson Syndrome: autosomal recessive, sensorineural deafness

62

Drug-induced long QT caused by:

ABCDE

anti Arrhythmics (class 1A, III)
anti Biotics (macrolides)
anti "C" ychotics (haloperidol)
anti Depressants (TCAs)
anti Emetics (ondansetron)

63

Brugada Syndrome

Autosomal dominant disorder most common in Asian males

ECG pattern of pseudo-right bundle branch block and ST elevations in V1-V3.

Higher risk of ventricular tachyarrhtymias and SCD. Prevent SCD with implantable cardioverter-defribrillator (ICD)

64

Wolff-Parkinson-White Syndrome

Most common type of ventricular pre-excitation syndrome.

Abnormal fast accessory conduction pathway from atria to ventricle (bundle of Kent) bypasses the rate-slowing AV node

This leads to ventricles beginning to partially depolarize earlier leading to characteristic delta wave with widened QRS complex and shortened PR interval on ECG.

May result in reentry circuit leading to supraventricular tachycardia

65

AFib on ECG

Chaotic and erratic baseline (irregularly irregular) with no discrete P waves in between irregularly spaced QRS complexes.

Associated with: (7)
HTN
CAD
Rheumatic heart disease
Binge drinking (holiday heart)
HF
Valvular disease
Hyperthyroidism

Can result in atrial stasis and lead to cardioembolic events.

Tx includes antithrombotic therapy (warfarin), rate control (B blockers, non-dihydropyridine Ca channel blockers, digoxin), rhythm control (class 1C or 3 antiarrhtymics) and or/ cardioversion (pharm or electrical)

66

Atrial flutter on ECG

A rapid succession of identical, back-to-back atrial depolarization waves. The identical appearance accounts for the "sawtooth" appearance of the flutter waves.

Management similar to Afib (rate control, anticoagulation, caridoversion). Definitive treatment is catheter ablation

67

VFib on ECG

A completely erratic rhythm with no identifiable waves. Fatal arrhythmia without immediate CPR and defibrillation

68

1st degree AV block on ECG

The PR interval is prolonged (greater than 200 ms). Benign and asymptomatic. No Tx required

69

2nd degree AV block - Mobitz type 1 (Wenckebach) on ECG

Progressive lengthening of PR interval until a beat is "dropped" ( a P wave not followed by a QRS complex).

Usually asymptomatic.

Variable RR interval with a pattern (regularly irregular)

70

Mobitz type II on ECG

Dropped beats that are not preceded by a change in the length of PR interval (as in type 1). May progress to 3rd degree block.

Often treated with pacemaker

71

3rd degree (complete) AV block on ECG

The atria and ventricles beat independently of each other. Both P waves and QRS complexes are present, although the P waves bear no relation to the QRS complexes. Atrial rate faster than ventricular rate.

Usually treated with pacemaker.

Lyme Disease can result in 3rd degree block

72

Atrial natriuretic peptide

Released from atrial myocytes in response to increased blood volume and atrial pressure.

Acts via cGMP.

Causes vasodilation and lower Na reabsorption at the renal collucting tubule. Dilates afferent renal arterioles and constricts efferent arterioles, promoting diuresis and contributing to "aldosterone escape" mechanism

73

B-type (Brain) naturietic peptide

Released from ventricular myocytes in response to increased tension. Similar physiologic action to ANP, with longer half-life. BNP blood test used for diagnosing HF (very good negative predictive value)

Available in recombinant form (nesiritide) for treatment of HF

74

Cushing reaction triad

Hypertension
Bradycardia
Respiratory depression

75

Right to Left Shunts

Congenital heart defects

Early cyanosis - "blue babies." Often diagnosed prenatally or become evident immediately after birth. Usually require urgent surgical correction and/or maintenance of a PDA.

5 T's

1) Truncus arteriosus (1 vessel)
2) Transposition (2 vessels)
3) Tricuspid atresia (3 = tri)
4) Tetralogy of Fallot (4 = tetra)
5) TAPVR (5 letters)

76

Persistent Truncus arteriosus

Congenital heart defect

Truncus arteriosus fails to divide into pulmonary trunk and aorta due to lack of aorticopulmonary septum formation. Most patients have accompanying VSD.

77

D-Transposition of great vessels

Congenital heart defect

Aorta leaves RV (anterior) and pulmonary trunk leaves LV (posterior). This leads to separation of systemic and pulmonary circulations. Not compatible with life unless a shunt is present to allow mixing of blood (e.g. VSD, PDA, or patent foramen ovale)

Due to failure of the aorticopulmonary septum to spiral

Without surgical intervention, most infants die within the first few months of life.

78

Tricuspid atresia

Congenital heart defect

Absence of tricuspid valve and hypoplastic RV - requires both an ASD and VSD for viability

79

Tetralogy of Fallot

Congenital heart defect

Caused by anterosuperior displacement of the infundibular septum. Most common cause of early childhood cyanosis.

1) Pulmonary infundibular stenosis (most important determinant for prognosis)

2) Right ventricular hypertrophy - boot shaped hear on CXR

3) Overriding aorta

4) VSD

Pulmonary stenosis forces R-L flow across VSD leading to early cyanotic "tet spells," RVH.

Squatting: Increases SVR, lowers R-L shunt and improves cyanosis

Tx = early surgical correction

80

Total anomalous pulmonary venous return (TAPVR)

congenital heart defect

Pulmonary veins drain into right heart circulation (SVC, coronary sinus, etc): associated with ASD and sometimes PDA to allow for R-L shunting to maintain CO.

81

Left-Right shunts

LATE cyanosis - blue kids

VSD
ASD
PDA

Frequency: VSD > ASD > PDA

82

Ventricular septal defect

Most common congenital cardiac defect. Asymptomatic at birth, may manifest weeks later or remain asymptomatic throughout life. Most self resolve; larger lesions may lead to LV overload and HF

83

Atrial septal defect

Defect in interatrial septum; loud S1; wide, fixed split S2.

ostium secundum defects are most common and usually occur as isolated findings.

Ostium primum defects are rarer yet usually occur with other cardiac anomalies.

Symptoms range from none to HF. Distinct from patent foramen ovale in that septa are missing tissue rather than unfused.

84

Patent ductus arteriosus

In fetal period, shunt is R-L (normal). In neonatal period, lower lung resistance leads to shunt becoming L-R leading to progressive RVH and/or LVH and HF

Associate with a continuous, "machine-like" murmur. Patency is maintained by PGE synthesis and low O2 tension. Uncorrected PDA can eventually result in late cyanosis in the lower extremities (differential cyanosis)

Indomethacin ends patency of PDA; PGE keeps it open (may be necessary to sustain life in conditions such as transposition of the great vessels).

PDA is normal in utero and normally closes only after birth

85

Eisenmenger syndrome

Uncorrected L-R shunt (VSD, ASD, PDA) lead to increased pulmonary blood flow leading to pathologic remodeling of vasculature leading to pulmonary arterial HTN. RVH occurs to compensate leading to shunt becoming R-L.

Causes late cyanosis, clubbing, and polycythemia. Age of onset varies.

86

Coarctation of the aorta

Aortic narrowing near insertion of ductus arteriosus (juxtaductal). Associated with bicuspid aortic valve, other heart defects, and Turner Syndrome.

HTN in upper extremities and weak, delayed pulse in lower extremities (brachial-femoral delay). With age, collateral arteries erode ribs (notched appearance on CXR)

87

Alcohol exposure in utero (fetal alcohol syndrome) leads to what congenital heart defects?

VSD
PDA
ASD
Tetralogy of Fallot

88

Congenital rubella leads to what congenital heart defects?

Septal defects
PDA
Pulmonary artery stenosis

89

Down Syndrome leads to what congenital heart defects?

AV Septal defect (endocardial cushion defect)
VSD
ASD

90

Infant of diabetic mother leads to what congenital heart defects?

Transposition of great vessels

91

Marfan Syndrome leads to what congenital heart defects?

MVP
Thoracic aortic aneurysm and dissection
Aortic regurgitation

92

Prenatal lithium exposure leads to what congenital heart defects?

Ebstein anomaly

93

Turner Syndrome leads to what congenital heart defects?

Bicuspid aortic valve
Coarctation of aorta

94

Williams Syndrome leads to what congenital heart defects?

Supravalvular aortic stenosis

95

22q11 syndromes lead to what congenital heart defects?

Truncus arteriosus
Tetralogy of Fallot

96

Anteroseptal infarct (LAD) on ECG

V1-V2

97

Anteroapical (distal LAD) infarct on ECG

V3-V4

98

Anterolateral (LAD or LCX) infarct on ECG

V5-V6

99

Lateral (LCX) infarct on ECG

I, aVL

100

Inferior (RCA) infarct on EKG

II, III, aVF

101

Dressler Syndrome

Autoimmune phenomenon resulting in fibrinous pericarditis several weeks post-MI)

102

Acute bacterial endocarditis - organisms

S. aureus (high virulence)

Large vegetations on previously normal valves. Rapid onset.

103

Subacute bacterial endocarditis - organisms

strep viridans (low virulence). Smaller vegetations on congenitally abnormal or diseased valves. Sequela of dental procedures. Gradual onset.

104

Bacterial endocarditis - organism present in colon cancer

S. bovis

105

Bacterial endocarditis - organism present on prosthetic valves

S. epidermidis

106

bacterial endocarditis - culture is negative

Coxiella burnetii
Bartonella

HACEK

Haemophilus
Actinobacillus
Cardiobacterium
Eikenella
Kingella

107

Bacterial endocarditis signs

FROM JANE

Fever
Roth spots
Osler nodes
Murmur

Janeway lesions
Anemia
Nail-bed hemorrhage
Emboli

108

Beck triad for cardiac tamponade

Hypotension
Distended neck veins
Distant heart sounds

109

Angiosarcoma

a vascular tumor

Rare blood vessel malignancy typically occurring in the head, neck, and breast areas. Usually in elderly, on sun-exposed areas. Associated with radiation therapy and chronic postmastectomy lymphedema.

Hepatic angiosarcoma associated with vinyl chloride and arsenic exposure. Very aggressive and difficult to resect due to delay in diagnosis.

110

Bacillary angiomatosis

vascular tumor

benign capillary skin papules found in AIDS patients. Caused by bartonella henselae infections. Frequently mistaken for Kaposi sarcoma, but has a neutrophilic infiltrate

111

Cherry hemangioma

Vascular tumor

Benign capillary hemangioma of the elderly.

Does not regress. Frequency higher with age

112

Cystic hygroma

Vascular tumor

Cavernous lymphangioma of the neck

Associated with Turner Syndrome

113

Glomus tumor

Vascular tumor

Benign, painful, red-blue tumor under fingernails.

Arises from modified smooth muscle cells of the thermoregulatory glomus body

114

Kaposi Sarcoma

Vascular tumor

Endothelial malignancy most commonly of the skin, but also mouth, GI tract, and respiratory tract.

Associated with HHV-8 and HIV.

Frequently mistaken for bacillary angiomatosis, but has lymphocytic infiltrate

115

Pyogenic granuloma

Vascular tumor

Polypoid capillary hemangioma that can ulcerate and bleed

Associated with trauma and pregnancy

116

Strawberry hemangioma

Vascular tumor

Benign capillary hemangioma of infancy

Appears in first few weeks of life (1/200 births): grows rapidly and regresses spontaneously by 5-8 years old