Anatomy/Physiology Flashcards
1
Q
Acute Marginal Artery
A
supplies right ventricle
2
Q
Post. descending/interventircular artery
A
supplies posterior 1/3 of IV septum and posterior walls of ventricles
3
Q
Left anterior descending artery
A
supplies anterior 2/3 of IV septum, anterior papillary muscles and anterior surface of left ventricle
4
Q
Left Circumflex coronary artery
A
supplies lateral and posterior walls of left ventricle
5
Q
Blood supply for SA and AV nodes
A
Right Coronary Artery - infarct can cause nodal dysfx
6
Q
Right Dominant Circulation
A
85% population, posterior descending artery arises from RCA
7
Q
Left Dominant Circulation
A
8% of population, posterior descending artery arises from LCA
8
Q
Codominant circulation
A
7% of population, posterior descending artery arises from both Left Circumflex artery and RCA
9
Q
Peak of coronary blood flow
A
Early Diastole
10
Q
Most posterior part of heart
A
Left Atrium, enlargment can cause dysphagia or hoarseness (compresses Left reccurrent laryngeal)
11
Q
Cardiac Output
A
SV * HR -or-
rate of O2 consumption)/(arterial O2 content-venous O2 content
12
Q
Mean Arterial Pressure
A
MAP = CO * TPR
2/3DBP + 1/2SBP
13
Q
Pulse Pressure
A
systolic - diastolic
proportional to SV
inversely proportional to arterial compliance
14
Q
Stroke Volume
A
EDV-ESV
15
Q
Cardiac Output during exercise
A
Early - CO is maintained by increase HR and SV
Late - CO is maintained by increased HR only (SV plateaus)
16
Q
Causes for increased Pulse Pressure
A
Hyperthyroidism, Aortic regurgitation, arteriosclerosis, obstructive sleep apnea, transiently with exercise
17
Q
Causes for decreased Pulse Pressure
A
aortic stenosis, cardiogenic shock, cardiac tamponade, and advanced heart failure
18
Q
Causes for increased stroke volume
A
increased contractility, increased preload, or decreased afterload
anxiety, pregnancy, exercise
19
Q
Increased intracellular Calcium
A
increases contractility
20
Q
Decreased Extracellular Sodium
A
increases contractility because it decreases the Na/Ca exchanger
21
Q
Catecholamines effect on Heart
A
Increases activity of calcium pump in sarcoplasmic reticulum
22
Q
Digitalis on Contractility
A
blocks Na/K pump thus increase intracellular Na and decreasing Na/Ca exchanger therefore INCREASING intracellular Calcium
23
Q
Ways to decrease contractility and stroke volume
A
beta-1 blockade, HF with systolic dysfunction, acidosis, hypoxia/hypercapnea, non-dihydropyridine CCB
24
Q
Increase of myocardial O2 demand
A
increased afterload, increased contractility, increased heart rate, increased ventricular diameter
25
Preload
depends on venous tone and circulating blood volume
| approximated by ventricular EDV
26
Venodilators
nitroglycerin, decreases preload
27
Afterload
approximated by MAP
28
Compensation for increased afterload
LV compensates by thickening (hypertrophy) to decrease wall tension
29
Drugs that decrease both preload and afterload
ACE-inhibitors and ARBs
30
Vasodilators
hydralazine, decrease afterload
31
Wall Tension
Associated with Afterload
| Pressure*radius) / (2*wall thickness
32
Ejection Fraction
EF = (SV)/(EDV) or (EDV-ESV)/EDV
| left ventricular EF is an index of ventricular contractility
33
Normal EF
>55%
34
EF in systolic heart failure
<55%
35
EF in diastolic heart failure
normal, >55%
36
Pressure =
Pressure = flow * resistance
37
Resistance of vessels in series
TR = R1+R2+R3...
38
Resistance of vessels in parallel
1/TR = 1/R1 + 1/R2 + 1/R3....
39
Causes of increased viscosity of blood
polycythemia, hyperproteinemic states (multiple myeloma), spherocytosis
40
Causes of decreased velocity of blood
ANEMIA
41
Resistance equation
(8*(viscosity)*length) / (pi*r^4)
42
Type of vessel that accounts for majority of TPR
arterioles, they regulate capillary flow
43
Inotropy
Strength of contraction
44
(+) inotropy
catecholamines, digoxin
45
negative inotropy
uncompensated heart failure and narcotic overdose
46
Decreases venous return
acute hemorrhage, spinal anesthesia
47
Increases venous return
fluid infusion, sympathetic activity
48
Increases TPR
vasopressors
49
Decreases TPR
Exercise and AV shunt
50
S1
mitral and tricuspid valve closure. Loudest at mitral area
51
S2
aortic and pulmonary valve closure, loudest at left sternal border
52
S3
Early diastole during rapid ventricular filling phase
associated with mitral regurgitation and CHF
more common in dilated ventricles
53
Heart sound normal in children and pregnant women
S3
54
S4
atrial kick - in late diastole, High atrial pressure. associated with ventricular hypertrophy. Left atrium must push against stiff LV wall.
55
Jugular venous pulse - a wave
atrial contraction
56
Jugular venous pulse - c wave
RV contraction (close tricuspid valve)
57
Jugular venous pulse -x descent
atrial relaXation and downward displacement of close tricuspid valve during ventricular contraction
absent in tricuspid regurg
58
Jugular venous pulse -v wave
increased right atrial pressure due to filling against closed tricuspid valve
59
Jugular venous pulse - y descent
blood flow from Rt Atria to Rt Ventricle
60
Normal Heart Split
delayed closure of pulmonic valve during inspiration
| from decreased intrathoracic pressure so more blood returns
61
Wide Splitting
Seen in conditinos that dela right ventricular emptying
pulmonic stenosis, RBBB
Exaggeration of normal splitting
62
Fixed Splitting
Seen in ASD which causes left-to-right shunt
| regardless of breath, pulmonic valve is greatly delayed due to increased blood flow
63
Paradoxical Splitting
Conditions that delay LV emptying
aortic stenosis, LBBB
P2 closes before A2 and on inspiration, no split
64
Auscultation over aortic area
Systolic murmurs like: aortic stenosis, flow murmur, aortic valve sclerosis
65
Auscultation over Left Sternal Border
Diastolic murmurs: aortic regurgitation, pulmonic regurgitation
Systolic murmurs: hypertrophic cardiopathy
66
Auscultation over Pulmonic Area
Systolic ejectino murmur: pulmonic stenosis and physiologic murmur
67
Auscultation over tricuspid area
Pansystolic murmur: tricuspid regurgitation, VSD
| Diastolic Murmur: tricuspid stenosis, ASD
68
Auscultation over Mitral Valve Area
Systolic Murmur: mitral regurgitation
| Diastolic Murmur: mitral stenosis
69
Inspiration
increases intensity of right heart sounds
70
Hand Grip
increases intensity of MR, AR, VSD murmurs
| MVP: increases murmur intensity and later onset of click/murmur
71
Valsalva, Standing
increases hypertrophic cardiomyopathy murmur
| MVP: decreases murmur intensity, earlier onset of click/murmur
72
Rapid Squating
increases intensity of aortic stenosis murmur
| MVP: increases murmur intensity and later onset of click/murmur
73
Systolic Heart Sounds
aortic/pulmonic stenosis, AV regurgitation, VSD
74
Diastolic Heart Sounds
Aortic/Pulmonic Regurgitation, AV stenosis
75
Holosystolic, high-pitched "blowing murmur" at apex and radiates toward axilla
Mitral Regurgitation
76
Holosystolic, high-pitched "blowing murmur" loudest left sternum 5th intercostal space to right sternal border
Tricuspid regurgitation
77
Crescendo-decrescendo systolic ejection murmur
| loudest at heart base; radiates to carotids
Aortic Stenosis
78
"pulsus parvus et tardus"
pulses are weak with a delayed peak, aortic stenosis
| can lead to syncope, angina and dyspnea on exertion
79
Holosystolic, harsh-sounding murmur. Loudest at tricuspid area, accentuated with hand grip
VSD
80
Late systolic Crescendo with midsystolic click
MVP
81
Cause of midsystolic click
due to sudden tensing of chordae tendinae
82
High-pitched "blowing" early diastolic decrescendo murmur. Bounding pulses and head bobbing
Aortic Regurgitation (wide pulse pressure is chronic)
83
Aortic Root dilation, bicuspid aortic valve, endocarditis, or rheumatic fever
Aortic Regurgitation
84
Follows opening snap. delayed rumbling diastolic murmur
Mitral Stenosis
85
Continuous machine-like murmur, loudest at S2, left infraclavicular area
PDA, often due to congenital rubella
86
ACh/adenosine on Heart
decrease the rate of diastolic depolarization and HR (longer for depolarization to occur)
87
P wave
atrial depolarization (repolarization of atria in QRS)
88
PR interval
conduction delay through AV node (normally <200msec)
89
QRS complex
ventricular depolarization
90
QT interval
Mechanical contraction of ventricles
91
T wave
Ventricular repolarization
92
T wave inversion
recent MI
93
ST segment
Isoelectric, ventricles depolarized
94
U wave
caused by hypokalemia, bradycardie
95
Speed of conduction
Purkinje > Atria > ventricles > AV node
96
Pacemakers
SA > AV > bundle of His/Purkinje/Ventricles
97
Tx of Torsades de Pointes
Magnesium Sulfate
98
Drugs that prolong QT
Sotalol, Risperidone, Macrolides, Chloroquine, Protease inhibitor (-navir), quinidine, Class Ia and III antiarrhythmics, thiazides
99
Romano-Ward Syndrome
autosomal dominant, pure cardiac phenotype (no deafness) congenital long QT syndrome
100
Jervell and Lange-Nielsen Syndrome
Autosomal Recessive, Sensorineural deafnes, congenital long QT syndrome
101
Delta wave
Wolff-Parkinson-White Syndrome; abnormal fast accessory conduction pathway from atria to ventricle (bundle of Kent) to bypass the rate-slowing AV node so ventricles depolarize earlier
102
Prolonged PR interval (>200msec)
1st Degree AV block
103
Progressive lengthening of PR interval until a beat is dropped
2nd degree Mobitz Type I (Wenckebach)
104
Chaotic and erratic baseline (irregularly irregular) with nodiscrete P waves inbetween irregularly spaced QRS complex
Atrial fibrillation
105
"saw tooth" appearance of flutter waves
Atrial flutter
106
Tx for Atrial Flutter
Class IA, IC, or III antiarrhythmics
Rate Control use beta-blocker or CCB
Definitive tx: catheter ablation
107
completely erratic rhythm with no identifiable waves
Ventricular arrhythmia (tx with CPR and defibrillation)
108
Dropped QRS beats, no change in PR interval
(2 more P waves than QRS)
(3 more P waves than QRS)
2nd degree AV block; Mobitz type II
2: 1
3: 1
109
2nd degree AV block; Mobitz type II
Pacemaker
110
Atria and ventricle beat independently of each other
3rd Degree heart block or complete heart blood, tx with a pacemaker
111
Lyme disease
can result in 3rd degree heart block
112
"aldosterone escape" mechanism
ANP
113
Release from atrial myocytes in response to increase blood volume and atrial pressure
ANP
114
Cause vasodilation and decrease sodium reabsorption at renal collecting tubues. Constricts efferent arterioles and dilates afferent arterioles
ANP
115
Released from ventricular myocytes in response to increased tension
B-type (brain) natriuretic peptide
116
longer t1/2 than ANP, with similar mechanism
BNP
117
Nesiritide
recombinant form of BNP for treatment of heart failure
118
Aortic Arch Receptors
vagus nerve to solitary nucleus of medulla responds to increased BP only
119
Carotid sinus receptors
glossopharyngeal nerve to solitary nucleus of medulla, responds to increase and decreased BP
120
Baroreceptors
respond to hypotension, decrease of afferent firing increase efferent sympathetic firing and decrease parasympathetic leading to vasoconstriction. Important in hemorrhage
121
Carotid Massage
increased pressure on carotid sinus will increase AV node refractory period and decrease HR
122
Cushing Reaction
hypertension, bradycardia and respiratory depression
| increased ICP contricts arterioles leading to cerebral ischemia and sympathetics thus HTN and reflex bradycardia
123
Peripheral Chemoreceptors
carotid and aortic bodies stimulated by decreased oxygen when pO2 is <60mmHg
124
Central Chemoreceptors
stiulated by changes in pH and pCO2 of brain interstitial fluid, which in turn are influenced by arterial CO2
125
Organ with largest blood flow
Lung
126
Largest share of systemic cardiac output
Liver
127
Highest blood flow per gram of tissue
Kidney
128
Largest AV O2 difference because O2 extraction is ~80%
Heart
129
Increased oxygen demand for heart is met by
increase coronary artery flow
130
PCWP in mitral stenosis
PCWP > LV diastolic pressure
| normal <12
131
Autoregulation blood flow in heart
Local metabolites (vasodilatory) - CO2, adenosine, NO
132
Autoregulation blood flow in Brain
Local metabolites (vasodilatory) - CO2 (pH)
133
Autoregulation blood flow in Kidneys
Myogenic and tubuloglomerular feedback
134
Autoregulation blood flow in Lungs
Hypoxia causes vasoconstriction
135
Autoregulation blood flow in Skeletal Muscle
Local Metabolites - lactate, adenosine, K, H, CO2
136
Autoregulation blood flow in Skin
Sympathetic stimulation most important mechanism - temperature control
137
Whose head is on a rat?
Molly's!!! (weird punch bowl)
