Cardiac Pathophysiology Flashcards
1
Q
What are the three branches off of the aorta?
A
Brachiocephalic artery
Left common carotid artery
Left subclavian artery
2
Q
What two branches does the brachiocephalic artery divide into?
A
Right common carotid and the Right subclavian arteries
3
Q
What is wall tension?
A
The tension in the LV wall must generate to eject the stroke volume
4
Q
What components make up a person’s cardiac output?
A
CO = HR x SV (contractility and vascular tone)
5
Q
How many segments is the aorta divided into?
A
Three: Ascending, aortic arch, descending aorta
6
Q
What physiologic component has the greatest increase in myocardial O2 demand of the heart?
A
Increased LV wall tension
7
Q
What is a hemodynamic consequence of cross clamping for cardiac bypass?
A
Elevated MAP –> HTN
8
Q
Where is the tricuspid valve located?
A
Between the right atria and ventricle
9
Q
Where is the mitral valve located?
A
Between the left atria and ventricle
10
Q
In what direction does the heart normally pump?
A
In an elliptical fashion
11
Q
What is the predominating ventricle when viewing an anterior approach of the heart?
A
RV
12
Q
How many pulmonary arteries are there?
A
Two: Right and Left
13
Q
How many pulmonary veins are there?
A
Four
14
Q
What is the worse type of aortic aneurysm to have?
A
Ascending, when you clamp blood flow will cease to the brain
15
Q
What is the artery of adamkiewicz?
A
artery that provides perfusion to the spinal cord
16
Q
What is unique about the artery of adamkiewicz?
A
Its location varies in individuals
17
Q
What coronary artery perfuses the inferior portion of the heart?
A
Right coronary artery
18
Q
What coronary artery perfuses the anteroseptal portion of the heart?
A
LAD
19
Q
What coronary artery perfuses the anteroapical portion of the heart?
A
Distal portion of LAD
20
Q
What coronary artery perfuses the anterolateral portion of the heart?
A
Circumflex artery
21
Q
What coronary artery perfuses the posterior portion of the heart?
A
Right coronary artery
22
Q
What causes concentric hypertrophy?
A
Chronic pressure overload as occurs with chronic hypertension or aortic valve stenosis
23
Q
How does concentric hypertrophy occur?
A
The ventricular chamber radius may not change; however, the wall thickness greatly increases as new sarcomeres are added in-parallel to existing sarcomeres.
24
Q
What complications are associated with concentric hypertrophy?
A
This type of ventricle becomes “stiff” (i.e., compliance is reduced), which can impair filling and lead to diastolic dysfunction.
25
What causes eccentric hypertrophy?
Occurs when there is both volume and pressure overload.
26
How does eccentric hypertrophy occur?
Chamber dilation occurs as new sarcomeres are added in-series to existing sarcomeres.
27
What is the normal RA pressure?
4mmHg (Range 2-6mmHg)
28
What is the normal saturation of blood entering the RA?
75%
29
What is normal RV pressure?
25mmHg Ranges given for Systolic 15-30mmHg
| 0 mmHg Ranges given for Diastolic 2-8mmHg
30
What is the normal saturation of blood in the RV?
75%
31
What is normal PA pressure?
25 mmHg Ranges given for systolic 15-30mmHg
| 10 mmHg Ranges given for diastolic 8-15mmHg
32
What is the saturation of the blood in the pulmonary arteries before it has reached the lungs?
75%
33
What is the saturation of the blood in the pulmonary veins?
95%
34
What is the normal LA pressure?
6mmHg Range 4-12mmHg
35
What is the normal LV pressure?
100 mmHg
| 0 mmHg
36
What is the normal pressure in the aorta?
100mmHg
| 70 mmHg
37
What occurs in stable angina?
Lumen narrowed by plaque and inappropriate vasoconstriction
38
What occurs in unstable angina?
Plaque rupture, platelet aggregation, thrombus formation and unopposed vasoconstriction
39
What causes variant angina?
No overt plaques and intense vasospasm
40
What order does the ischemic cascade occur?
Occlusion of artery --> stiffness during filling --> reduced emptying --> Increased heart and lung pressure --> EKG changes --> Anginal chest pain
41
What causes pulmonary congestion during myocardial ischemia?
Decreased systolic function and decreased diastolic compliance
42
How is stroke volume represented in a cardiac pressure volume loop?
The area of the figure
43
What should occur normally in diastole?
The ventricles fill with blood
44
What should occur normally in systole?
The ventricles pump out about 60% of the blood
45
What occurs in diastole with systolic dysfunction?
The enlarged ventricles fill with blood
46
What occurs in systole with systolic dysfunction?
The ventricles pump out less than 40-50% of the blood
47
What occurs in diastole with diastolic dysfunction?
The stiff ventricles fill with less blood than normal
48
What occurs in systole with diastolic dysfunction?
The ventricles pump out about 60% of the blood but the amount may be lower than normal
49
What what decade of life does initial lesion and fatty streaks occur in formation of atherosclerosis?
From the first decade
50
What decade of life do intermediate lesions and atheromas occur in formation of atherosclerosis?
From third decade
51
In what decade does fibroatheroma and complicated lesions occur in formation of atherosclerosis?
From fourth decade
52
What is the main growth mechanism for atherosclerosis in the first three decades of life?
Growth mainly by lipid addition
53
What causes growth of atherosclerosis after the forth decade of life?
Increased smooth muscle and collagen
| Thrombosis and or hematoma
54
What is considered an initial lesion in relation to atherosclerosis?
Histologically normal
Macrophage infiltration
Isolated foam cells
55
What causes the fatty streak in atherosclerosis formation?
Mainly intracellular lipid accumulation
56
What is considered an intermediate lesion in relation to atherosclerosis?
Intracellular lipid accumulation
| Core of extracellular lipid
57
What causes an atheroma?
Intracellular lipid accumulation
| Core of extracellular lipid
58
What is considered a complicated lesion in relation to atherosclerosis?
Surface defect
Hematoma Hemorrhage
Thrombosis
59
What causes a fibroatheroma?
Single or multiple lipid cores
| Fibrotic/calcific layers
60
How do we calculate wall tension?
Pressure = Tension in wall
| Radius
61
When does myocardial ischemia occur?
When oxygen demand exceeds oxygen supply
62
When myocardial ischemia occurs, what two factors cause pulmonary congestion?
Decreased systolic function and decreased diastolic compliance
63
What does myocardial ischemia cause?
Decreased systolic function
Decreased diastolic function
Papillary muscle dysfunction
Increased sympathetic tone
64
What is the most common type of HTN?
Essential, meaning there is no identifiable cause
65
What are the two main effects of systemic HTN?
Increased after load
| Arterial damage
66
How does an increased after load affect the body?
Systolic dysfunction
LVH
Increased myocardial demand
67
How does arterial damage affect the body?
Accelerated atherosclerosis
| Weakens vessel wall
68
What conditions can occur if there is weakening to the aorta as well as accelerated atherosclerosis?
Aortic aneurysm
Dissection
Stroke
69
What is congestive heart failure?
When the heart is unable to pump blood at rate to meet tissue metabolic requirements or do so only with elevated filling pressures
70
What is the end result of CHF?
The heart transforms into a neuroendocrine organ meaning catecholamines are depleted and bear hormones shifts the heart from responsive SNS to responsive to adrenal medulla
71
What type of symptoms are seen with left heart failure?
Pulmonary symptoms
72
What type of symptoms are seen with right heart failure?
Systemic symptoms
73
What are the evolutionally steps to CHF?
Cardiac injury --> neurohormonal activation --> cardiac remodeling --> fluid retention --> peripheral vasoconstriction --> contractile failure
74
What are the four factors that can be manipulated to improve CO?
HR
Preload
Afterload
Contractility
75
What conditions are known to cause heart failure?
```
Ischemia
Valvular disease
Cardiomyopathy
Restrictive disease
Non cardiac causes
```
76
What non cardiac diseases can cause heart failure?
HTN, PE, High output states and thyrotoxicities
77
What is the most common cause of heart failure?
Ischemia
78
What hormone is known to be cardioprotective?
Estrogen, many post menopausal women develop cardiac issues
79
What is the problem associated with systolic dysfunction?
Problem with LV ejection which causes decreased contractility and SV at any given end diastolic volume
80
What is the problem associated with diastolic dysfunction?
Problem with LV filling due to decreased compliance, however contractility is normal
Impaired relaxation and restricted filling
81
How does the heart normal fill in diastole?
Energy dependent process requiring ATP to move Ca out
| No O2 = no ATP = can't relax heart
82
What pathologies are known to cause systolic HF?
Ischemic damage/dysfunction
Chronic pressure overload
Chronic volume overload
Non ischemic cardiomyopathy
83
What are majority of CHF cases the result of?
Impair contractile function (EF
84
What mechanism is used to compensate for the increased preload in systolic HF?
Frank Starling, however limited
85
What are characteristics of diastolic HF?
Reduced compliance with normal contractility (EF > 40-45%)
| Increased preload = increased LVEDP
86
What pathologies are known to cause diastolic HF?
Pathological myocardial hypertrophy
Restrictive cardiomyopathy
Aging
Ischemic fibrosis
87
What are the primary compensatory mechanisms when heart failure occurs?
```
Increased preload
Increased SNS tone
RAAS activated
AVP released
Ventricular remodeling
```
88
How does the SNS impact the heart?
Augments myocardial contractility
Increases HR and TPR (after load)
Arterial constriction
89
What occurs when chronic SNS activation is necessary for HF?
Decreased response to catecholamines (down regulated) predominately B receptors
90
Why is anesthesia so challenging in HF patients?
Catecholamine dependent, anesthesia causes a withdrawl of the SNS
91
How is the RAAS activated in HF patients?
Macula densa of kidney sense low sodium from decreased blood flow to kidneys causing the JG cells to release renin
92
What is the role of renin in the RAAS system?
It acts upon a circulating substrate, angiotensinogen, that forms angiotensin I.
93
Where is ACE located?
Predominately in the lungs, however found in the kidneys
94
What is the role of ACE in the RAAS?
Converts angiotensin I to angiotensin II
95
How does Angiotensin II contribute to HF?
```
Cardiac and vascular hypertrophy
Systemic vasoconstriction
Increases blood volume
Stimulates the release of aldosterone
Sodium and fluid retention
```
96
What causes the release of vasopressin?
SNS
Angiotensin II
Decreased atrial receptor firing
Hyperosmolarity
97
What effects does vasopressin have on the heart?
Agonizes V1 receptors which causes vasoconstriction and increases after load
Agonizes V2 receptors of the kidney which reduces free water clearance (hyponatremia)
98
How does vasopressin affect the heart?
Causes remodeling of the heart
99
What is ventricular remodeling?
Increased size of individual cells without increasing the quantity
100
What type of hypertrophy is seen in HF with pressure overload?
Concentric Hypertrophy
101
What are the properties of concentric hypertrophy?
Increased systolic wall stress
Large increase in wall thickness, decreased area for volume
Thickening of individual myocytes
Parallel replication of myofibrils
102
What type of hypertrophy is seen in HF with volume overload?
Eccentric hypertrophy
103
What are the properties of eccentric hypertrophy?
Increased diastolic wall stress
Mild increase n wall thickness
Myocyte elongation
Replication of myofibrils in series
104
What New York Hear Association classification is a person that ordinary physical activity does not cause symptoms?
Class I
105
What New York Hear Association classification is a person that symptoms occur at rest?
Class IV
106
What New York Hear Association classification is a person that less than ordinary activity causes fatigue, palpitations or dyspnea
Class III
107
What New York Hear Association classification is a person that ordinary activity causes fatigue, palpitations or dyspnea
Class II
108
What are indications seen on physical assessment that a patient has poor ventricular function?
S3 heart sound
EKG abnormalities
EF 15mmHg
ECHO shows hypokinesis, akinesia, aneurysm of ventricle dyskinesia
109
What physical assessment finding has the greatest predictive accuracy of HF?
S3 heart sound
110
What tool is used to assess the extent of HF without imaging or tests?
Metabolic score based on activities
111
How many mets are given to a patient that is able to play tennis, swim, partake in strenuous sports and had normal exercise tolerance?
>10 mets
112
How many mets are given to a patient that is able to climb stairs, have sex, gold, push a vacuum and jog with a moderate level of exercise tolerance?
4-10 mets
113
How many mets are given to a patient that is able to only eat, dress and walk around the house with minimal exercise tolerance?
1-4 mets
114
What is shock?
Abnormality of the circulatory system in which there is inadequate tissue perfusion because of relatively low or absolutely inadequate cardiac output
115
What are the four types of shock?
Hypovolemic
Distributive
Cardiogenic
Obstructive
116
How does increased levels of lactate affect the body?
Myocardial depressant, decreased peripheral response to catecholamine and can cause coma
117
What are the bodys compensatory mechanisms to shock?
Tachycardia, Vasoconstriction, Tachypnea, Restlessness, interstitial movement of fluid int capillaries, RAAS, vasopressin, plasma protein synthesis
118
What is the progression of shock?
Decreased pulse pressures or MAP
Decreased input to baroreceptors
Increased vasomotor discharge
Generalized vasoconstriction except to heart and brain
Tachycardia, water retention, decreased GFR, norepi, angiotensin II, carotid and aortic chemoreceptors
119
What is refractory shock?
Occurs when the patient does not die immediately but they do not get better
Eventually no response to vasopressors or volume
120
What factors can lead to refractory shock?
Decreased cerebral perfusion
Myocardial failure
Pulmonary damage --> ARDs
121
What is the cause of hypovolemic shock?
Inadequate blood volume
122
What are the four types of hypovolemic shock?
Hemorrhagic
Traumatic
Surgical
Burn
123
At what amount of blood loss is considered hemorrhagic hypovolemia?
5-15mL/kg
124
How long does it take for an increase in erythropoietin to occur?
4-8 weeks to restore RBC to normal
125
What is the cause of traumatic hypovolemia?
Damage to muscle and bone
126
Where is a common place that blood can hide in traumatic hypovolemia?
The thigh 1L may only increase diameter by 1cm
127
What is crush syndrome?
When pressure is relieved from previously crushed skeletal muscles, the muscles are reperfused and free radicals ae generated
Calcium, potassium, myoglobin and fat
128
What is surgical shock?
A combination of external hemorrhage bleeding into tissues and dehydration
129
What is cardiogenic shock?
When the pumping action go the heart is impaired to the point that tissue perfusion needs are not met
130
What are common causes of cardiogenic shock?
Dysrhythmias
Acute valvular dysfunction
Ruptured ventricle
Pump failure
131
What type of shock is considered warm shock?
Distributive shock
132
What is the cause of distributive shock?
Massive peripheral vasodilation
133
What is neurogenic shock?
An interruption in the transmission of autonomic activity results in vasodilation and peripheral pooling of blood
134
What is obstructive shock?
Congestion prevents blood from being distributed appropriately
135
What are common causes of distributive shock?
```
Cardiac tamponade
Massive PE
Tension pneumothorax
Pericardial disease
Cardiac tumor
```
136
When is recall most likely to occur in a compromised patient?
During times of HoTN and shock
137
Define cardiomyopathy?
A heterogenous group of diseases of the myocardium associated with mechanical or electrical dysfunction that usually exhibit inappropriate ventricular hypertrophy or dilation and are due to a variety of causes that are frequently genetic
138
What are the three types of cardiomyopathies?
Dilated
Hypertrophic
Restrictive
139
How does dilated cardiomyopathy occur?
There is myocardial injury that causes a decrease in contractility and SV
Results in increased ventricular filling pressures, LV dilation and decreased CO
140
What part of the cardiac cycle does dilated cardiomyopathy affect?
Problem with systole
141
What are common symptoms seen with dilated cardiomyopathy?
```
Pulmonary congestion
Systemic congestion
Low CO, fatigue weakness
HoTH, tachycardia, tachypnea
A-fib and complex PVC
```
142
What is the treatment for dilated cardiomyopathy?
Limit activity
Salt/fluid restriction
Pharmacology --> ACE inhibitors, diuretics, digoxin, anticoagulants
143
What are some poor prognosis indicators in dilated cardiomyopathy?
EF 20mmHg
| Cardiac index
144
What is the primary reason a patient required an immediate heart transplant?
Dilated cardiomyopathy
145
What is peripartum cardiomyopathy?
Enlargement of the heart due to preegnancy
146
What are risk factors for peripartum cardiomyopathy?
Obesity, smoking, ETOH abuse, multiple pregnancies, poor nutrition, personal history of myocarditis and age greater than 30
147
What drugs are desirable to use in peripartum cardiomyopathy?
After load reducing drugs
Inodilators
Nitrates
148
What is the most common genetic CV disease?
Hypertrophic cardiomyopathy
149
What is the presentation of hypertrophic cardiomyopathy?
Hypertrophy of the LV particularly the ventricular septum, in the absence of other causes
150
Why is there varying clinical manifestation seen in hypertrophic cardiomyopathy?
Morphologic and hemodynamic abnormalities
151
How does low stroke volume occur with hypertrophic cardiomyopathy?
Systolic anterior motion of the mitral valve leaflet created by LV ejection velocity during systole as blood is ejected into the aorta can cause obstruction of the LV outflow
152
What can make the CO worse in hypertrophic cardiomyopathy?
Obstruction is worse if preload is low
153
What part of the cardiac cycle does hypertrophic cardiomyopathy affect?
A disease of diastolic dysfunction
154
In hypertrophic cardiomyopathy, what does the heart depend on for ventricular filling?
Atrial kick, isn't able to passively fill during diastole
155
What is often the first sign of hypertrophic cardiomyopathy?
Sudden death from arrhythmias
156
What is the predominate cause of hypertrophic cardiomyopathy?
Genetic, myofibrils are not arranged appropriately
157
What are the variations of hypertrophic cardiomyopathy?
Symmetric hypertrophy
Atypical hypertrophy
Asymmetric septal hypertrophy without obstruction
Asymmetric septal hypertrophy with obstruction
158
What are the characteristics of symmetric hypertrophy?
Symmetric or concentric hypertrophy
159
What are the characteristics of atypical hypertrophy?
Atypical hypertrophy
| Small cavity remains
160
What are the characteristics of asymmetric septal hypertrophy without obstruction?
Cavity size reduced but mitral valve in appropriate position
161
What are the characteristics of asymmetric septal hypertrophy with obstruction?
Mitral valve presses against septum causing obstruction Systolic anterior motion of mitral valve (SAM)
Mitral regurgitation
162
What can cause an increase in LVOT obstruction with hypertrophic cardiomyopathy?
```
Increased contractility
Beta stimulation
Decreased preload/vasodilators
Tachycardia
Positive pressure ventilation
```
163
What can cause a decrease in LVOT obstruction with hypertrophic cardiomyopathy?
Beta blockers/ CCB
Increased after load/ alpha stimulation
Volatile anesthetics
Increase preload
164
What drugs should be avoided in patients with hypertrophic cardiomyopathy?
Nitroglycerin, sodium nitroprusside
165
What is the definitive treatment for patients with hypertrophic cardiomyopathy?
Heart transplant
May have palliative procedures such as myomectomy (resection of septum) and septal ablation to decrease the outflow obstruction
166
What occurs in restrictive cardiomyopathy?
The walls of the ventricles become still but not necessarily
167
What part of the cardiac cycle does restrictive cardiomyopathy affect?
Problem with diastole
168
What is the main cause of restrictive cardiomyopathy?
Amyloidosis --> infiltrative
169
What is the pathophysiology of restrictive cardiomyopathy?
Rigid myocardium causes increased diastolic ventricular pressure and decreased ventricular filling
170
How does restrictive cardiomyopathy typically present?
Heart failure without cardiomegaly, the chambers are still and non compliant
171
Why aren't patients with restrictive cardiopathy typically a candidate for a heart transplant?
Due to the systemic nature of the disease, even if receive new heart the process will reoccur with the new heart
172
What is the treatment for restrictive cardiomyopathy?
Diuretics to treat pulmonary and systemic congestion, supportive measurements
173
What are some anesthetic considerations for patients with restrictive cardiomyopathy?
Maintain NSR because stroke volume is fixed
| Maintain venous return and IV fluid volume
174
What structure supports the heart and limits displacement?
Pericardial Ligamentous
175
What structures protect the heart from external friction?
Pericardial Membranous
176
What encloses the heart in a relatively fluid filled envelop which prevents acute cardiac dilation and preserves normal ventricular compliance?
Pericardial Mechanical
177
How much fluid is usually in the pericardial sac?
10-20mL, up to 100mL can enter before symptoms are seen
178
What are common causes of cardiac tamponade?
Trauma
Post open heart surgery
Enlarging pericardial effusion
179
How can cardiac tamponade be life saving if blunt force trauma to the chest occurs?
Prevent exsanguination when heart/great vessels are traumatized
180
What are some common causes of a slowly enlarging pericardial effusion?
```
Bacterial/viral infections
Malignancy and Radiation
Uremia
Connective tissue disorder
Bleeding from anticoagulants
```
181
What is the best tool to determine if cardiac tamponade is present?
TEE
182
How is the transmural pressure affected in cardiac tamponade?
There is an increase in transmural pressure
| (pressure inside - pressure outside) the pressure inside becomes greater
183
Why does HoTN occur in cardiac tamponade?
Decreased pulmonary blood flow leads to a decrease in return to the LV
Decreased end diastolic volume
184
What is the end result of cardiac tamponade?
All chambers will equal outside of the heart leading to limited movement of blood
185
How can cardiac output be maintained during cardiac tamponade?
If CVP exceeds right ventricular end diastolic pressure
186
What does increased intrapleural pressure lead to?
Impaired diastolic filling of the heart, decreased stroke volume and HoTN with extreme SNS activation
187
What are telltale signs go advanced tamponade?
HoTN
Tachycardia
JVD
Pulsus paradoxes of > 10mmHg
188
What are the components of bucks triad and when does this occur?
Quiet heart sounds
Increased jugular venous pressure
HoTN
This occurs in advanced cardiac tamponade
189
What is the treatment for cardiac tamponade?
Surgery or a pericardial fluid removal
| Volume expansion and inotropic therapy are temporary measures
190
What should the provider anticipate treating after the cardiac tamponade has resolved?
HTN from extreme SNS activation
191
What anesthetic consideration should be made for a patient with cardiac tamponade?
Stable induction (Etomidate) extremely HoTN
Positive pressure ventilation can cause life threatening HoTN
Correct metabolic status and infuse catecholamines
192
What is known to cause acute pericarditis?
Viral infection or post infarction
193
Why symptoms are typically seen with acute pericarditis?
Chest pain aggravated by deep breathing, lying supine or coughing
Tachypnea
EKG changes --> ST elevation and T wave inversion
194
What is the treatment for acute pericarditis?
Aspirin
| Avoid steroids
195
What is known to cause constrictive pericarditis?
Usually idiopathic, but can be caused by previous cardiac surgery or radiation therapy, TB and calcifications
196
What symptoms are associated with constrictive pericarditis?
Increased CVP and low CO
| Decreased exercise tolerance, fatigue, JVD, hepatic congestion, ascites and peripheral edema
197
What other cardiac ailment can constrictive pericarditis be confused for?
Mimics RV failure without pulmonary congestion
198
What is the end result of constrictive pericarditis?
Eventually RA = RVEDP = LVEDP
| As pericardial pressure increases so does RAP in parallel
199
What is the treatment for constrictive pericarditis?
Pericardectomy
200
What is the square root signs and what cardiac ailment is it associated with?
A pressure contour recorded by cardiac catheterization, which consists of an elevation of the right ventricular diastolic pressure with early filling and a subsequent plateau, a finding suggestive of chronic constrictive pericarditis
201
What is regurgitation?
Leaking or back flow of blood across valve
202
What is stenosis?
Obstruction of forward flow across an opened valve
203
What occurs during systole?
The aortic valve and the pulmonic valves are open and the mitral and tricuspid valves are closed
204
What valvular disease is seen in systole?
Mitral regurgitation
| Aortic stenosis
205
What occurs during diastole?
Aortic and Pulmonic valves are closed while the tricuspid and mitral valves are closed
206
What valvular diseases occurs in diastole?
Aortic regurgitation
| Mitral stenosis
207
What is the issue in mitral stenosis?
Increased left trial after load results in impaired LV filling and reduced SV and CO
208
What is the result of mitral stenosis?
Problem with pressure = concentric hypertrophy of LA and atrophy of the LV
209
What type of symptoms are seen with mitral stenosis?
Pulmonary, blood backs up from LA to pulmonary vaculature
210
What is typically the cause of Rheumatic fever?
Group A strep
211
What are normal LA pressures?
8-10mmHg
212
What are anesthetic considerations for mitral stenosis?
Keep HR
213
What drugs are good to give to patients with mitral stenosis?
Opioids
Small dose of BB
Phenylephrine
214
What drugs are bad to give to patients with mitral stenosis?
Potent vasodilators
| Ketamine, etomidate, ephedrine and pavulon
215
What is an appropriate level to keep SVR in a patient with mitral stenosis?
SVR 800-1200mmHg
216
What is important to remember with mitral stenosis?
Sinus, slow and tight
217
When does mitral regurgitation occur?
During Systole
218
What is a major cause of acute mitral regurgitation?
Posterior papillary muscle ischemia
219
What occurs in mitral regurgitation?
Reduced forward SV, reduced backward flow from the LV into the LA
220
How does the heart initially respond to mitral regurgitation?
The CO increases due to FS and SNS however eventually contractility is less
221
What type of LV hypertrophy occurs with mitral regurgitation?
It is an issue with volume overload so eccentric LV hypertrophy occurs
222
What does the EF look like in patients with mitral regurgitation?
The EF is overestimated since blood is being ejected and flows in two directions
223
How do we calculate EF and what is a normal value?
EF = SV/ EDV x 100 = percentage
| Normal is > 60%
224
What are common causes of mitral regurgitation?
```
Annular calcifications
Papillary muscle rupture or dysfunction
Chordae tendonae rupture
Endocarditis
Rheumatic disease
MVP
```
225
What causes mitral valve prolapse?
Myxomatous degeneration of the posterior mitral valve leaflet which leads to systolic prolapse of the MV leaflets into the left LA
226
What can be used to diagnose mitral valve prolapse?
Murmur, mild systolic click and ECHO
227
What does MVP look like on an ECHO?
Valve leaflets balloon upward as the ventricle contracts
228
Which artery feeds the posterior leaflet of the MV?
Posterior descending artery
229
What arteries perfuse the anterior leaflet of the MV?
LAD and circumflex
230
What artery is perfusing if right dominance is noted in the chart?
A branch of the right coronary artery
231
What artery is perfusing if left dominance is noted in the chart?
A branch of the circumflex coronary artery
232
What artery is perfusing if co dominance is noted in the chart?
Anastomosis of the left and right coronary artery
233
What symptoms are typically seen with mitral regurgitation?
Low CO
Severe pulmonary congestion
A-Fib (remodeling of LA)
234
What are determinants of the amount of volume regurgitated?
```
Size of office
HR
LA-LV pressure gradient during systole
SVR
LA compliance
```
235
What is the treatment for mitral regurgitation?
Maintain contractility
Avoid Tachycardia and increased SVR
Relieve wall stress
236
What drugs are beneficial for mitral regurgitation?
```
Digoxin
Diuretics
Anticoagulation (A fib)
Vasodilators
ACE inhibitors
```
237
What should the provider remember about mitral regurgitation?
Fast Full and forward
Fast HR 80-100
Full beyond normal
Forward Avoid acute increases in after load
238
What should be avoided in mitral regurgitation?
Anything that will decrease HR and LV contractility
| Anything that will increase SVR
239
What is seen with PAC monitoring that can tell the degree of mitral regurgitation?
V waves
240
How does atrial compliance affect the symptoms a patient presents with mitral regurgitation?
Low atrial compliance will cause vascular congestion and edema
High atrial compliance will cause signs of decreased CO
241
What is the most beneficial intervention for patients with mitral regurgitation?
After load reducers, it increases SV and decreases the amount regurgitated
242
If what phase of the cardiac cycle is aortic stenosis a problem?
During systole
243
What type of LV hypertrophy occurs with aortic stenosis?
There is an issue with pressure, concentric hypertrophy occurs
244
What is the normal AO valve area compared to critical stenosis?
Normal: 3.5-4cm
| Critical stenosis:
245
Why is the atrial kick so important in aortic stenosis?
When the LA pressures are equal to the LV pressure there won't be any passive filling, the atrial kick is what allows blood to pass into the LV
246
Why might angina be the first sign that a patient has aortic stenosis?
Left ventricular end diastolic pressure increases causing the LAP to increase and O2 demand increases
247
What findings may indicate aortic stenosis on physical examination?
S4 mid systolic murmur and carotid pulses that come and go
| The intensity of the pulses vary
248
What is a poor indicator in the prognosis of aortic stenosis?
A-fib
249
What are considered the big three symptoms in aortic stenosis?
Angina
Syncope
CHF
250
What is the benefit of developing concentric hypertrophy in aortic stenosis?
Enables the LV to maintain SV by generating transvalvular pressure needed to cross the valve
251
Why does contractility progressively worse in patients with aortic stenosis?
Reduced LV compliance due to LVH and diastolic dysfunction
252
What is LV filling dependent on in aortic stenosis?
Atrial systole (atrial kick)
253
Why does Afib cause death in aortic stenosis?
Loss of atrial kick causing blood stasis in the heart
254
Why isn't bradycardia tolerated in aortic stenosis?
SV is fixed thus the only way to increase CO is HR
255
What are anesthetic considerations in patients with aortic stenosis?
Maintain NSR, SVR
| Avoid tachycardia and intravascular volume
256
What anesthetic should be avoided in patients with aortic stenosis?
Spinal anesthesia
257
Why do patients with aortic stenosis have a poor response to CPR?
It is difficult to generate enough pressure for forward flow
258
What occurs in aortic regurgitation?
Failure of the aortic leaflet to coapt causing SV to leak back into the LV
259
In what part of the cardiac cycle does aortic regurgitation occur?
Diastole
260
What type of LV hypertrophy is associated with aortic regurgitation?
Eccentric hypertrophy, there is a problem with volume into the LV
261
What problem develops after time in aortic regurgitation?
Initial volume overload of the LV then pressure overload develops
262
What population is aortic regurgitation most common in?
Males 30-60years old
263
What is the difference between chronic and acute aortic regurgitation?
Chronic occurs over time FS law to compensate at first, enlarge LA develops
Acute is not compatible with life, the patient has a normal size LA and fluid immediately backs up into the lungs causing HF
264
What are usually the causes of acute aortic regurgitation?
Trauma
| Aortic dissection
265
What pathologies have been known to cause aortic regurgitation?
```
Infective endocarditis
Rheumatic fever
Bicuspid aortic valve (supposed to be tricuspid)
Marfans syndrome
Syphilis
HTN
Aortic root dilation
Weight loss drugs
```
266
What are clinical signs of aortic regurgitation?
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Enlarged and displaced apex
Widened pulse pressures
Austin flint murmur
Bounding pulses
Aortic diastolic murmur
```
267
How does the aortic diastolic murmur change with severity?
Length correlates with severity
| Acute AR the murmur shortens as aortic DP = LVEDP and mitral pre-closure occurs
268
What is the pathology of acute AR?
Normal size LV is suddenly overloaded, high LAP causes pulmonary edema
269
What is the pathology of chronic AR?
Primarily LV dilation and LV hypertrophy
| Low aortic diastolic BP and widened pulse pressures are seen
270
What can be seen on a chest X-ray in patients with chronic AR?
Enlarged ventricular silhouette
271
What is the treatment for symptomatic AR?
Preserve LV function and aferload reduction
272
When is surgical intervention required in aortic regurgitation?
When the EF is
273
What makes up the total stroke volume in aortic regurgitation?
It is both the forward and the regurgitant volume combined
274
How should a patient with aortic regurgitation be managed?
Fast HR 80-100- deceases time in diastole
Full maintain preload
Forward avoid drugs that increase SVR and depress the myocardium
275
What drug can be used to maintain coronary perfusion?
Phenylephrine to maintain coronary perfusion pressure however over use can increase SVR and cause more regurgitation
276
What patient population require prophylactic antibiotics for dental care?
Prosthetic heart valve
Valvular repair
History of endocarditis
Congenital heart abnormalities ecept PFO
277
What are the three layers of the blood vessel?
Intimia
Media
Adventisia
278
What are characteristics of a true aneurysm?
The entire wall balloons out (all three layers)
279
What do we call true aneurysm that are symmetrical?
Fusiform aneurysms
280
What do we call true aneurysms that only dilate on one side?
Saccular aneurysms, one side has been exposed to chronically high BP than the other side
Also known as Beri aneurysms
281
What are characteristics of a pseudo aneurysm (false)?
Occur from a puncture to one of your vessels such as with an arterial injection and blood leaks outside of the vessel wall
Not actual dilation of the vessel, does have similar shape
282
What are major risk factors associated with aneurysm development?
Atherosclerosis
Smoking (directly damages blood vessel wall)
COPD
HTN
Male
Age > 65y/o (stiffened aorta)
Genertics --> connective tissue disorder or family Hx
283
What symptoms may be seen in an intact aneurysm?
Compression of structures (RLN, VC, trachea, esophagus)
| Pain in region
284
What symptoms may be seen in a ruptured aneurysm?
HoTN
Syncope
Hemypotysis
Vomiting blood
285
What is an aortic dissection?
When you develop a tear between your intima and media in your aortic wall
It tears the layers away from each other
286
What is a type A dissection?
The tear occurs in the ascending part of the aorta, before left subclavian artery
287
What is the goal of a Type A dissection?
To replace the affected aorta
288
How are type B dissections treated?
Conservative therapy
| Don't get as invasive because surgery is a larger risk that pharmacological management
289
What drugs are used to manage a type B dissection?
Low BP
SNP --> vasodilator decreased BP
BB --> beta receptors can't be activated to decrease HR
CCB --> vasodilates
