p.11
Cardiovascular Reflexes and Negative Feedback
What is a main function of cardiovascular reflexes?
To maintain a constant level of arterial pressure and blood volume.
p.3
Physical Factors Affecting Coronary Flow
What is the effective pressure gradient for coronary flow?
Aortic diastolic pressure minus intraventricular pressure.
p.11
Cardiovascular Reflexes and Negative Feedback
What is the function of a negative feedback loop in cardiovascular reflexes?
To counteract a change in a sensed variable.
p.8
Angina Pectoris Types and Features
What regions are generally involved in Prinzmetal Angina?
It generally involves a region of atherosclerotic lesion.
p.11
Cardiovascular Reflexes and Negative Feedback
What are examples of regulated variables in cardiovascular reflexes?
Blood pressure and blood volume.
p.7
Angina Pectoris Types and Features
What causes typical (exertional, secondary) angina pectoris?
Fixed obstruction (plaque) in the coronary artery.
p.7
Angina Pectoris Types and Features
What factors can exacerbate typical angina pectoris?
Exercise, cold, and stress.
p.12
Baroreceptor Function and Regulation
Where are the main locations of arterial baroreceptors?
Carotid sinus (junction of external and internal carotid artery) and aortic arch.
p.13
Baroreceptor Function and Regulation
What are arterial baroreceptors responsible for?
Arterial baroreceptors are responsible for detecting changes in blood pressure and initiating the baroreflex to maintain stable blood pressure.
p.5
Plaque Characteristics: Hard vs. Soft Plaque
What are the features of soft or vulnerable plaque?
Degradation exceeds growth, outward remodeling, thinning/erosion of cap, more prone to fissure/rupture, thrombosis, and myocardial infarction.
p.14
Cardiovascular Reflexes and Negative Feedback
What is the formula for blood pressure (BP)?
BP = CO x TPR (Cardiac Output x Total Peripheral Resistance).
p.5
Plaque Characteristics: Hard vs. Soft Plaque
Which type of plaque is more prone to fissure or rupture?
Soft or vulnerable plaque.
p.13
Baroreceptor Function and Regulation
How does baroreflex resetting affect individuals with hypertension?
In individuals with hypertension, the baroreflex is reset to a higher pressure, and the reflex tries to maintain this higher pressure even when antihypertensive drugs are given.
p.9
Myocardial Infarction and Cardiac Enzymes
When are cardiac troponins T and I released after a myocardial infarction?
4-6 hours after the infarct.
p.11
Cardiovascular Reflexes and Negative Feedback
What does the brain do in response to baroreceptor signals?
Evokes a pattern of autonomic nervous system (ANS) and/or hormonal changes that reverse the initial change.
p.13
Baroreceptor Function and Regulation
What factors can decrease baroreflex sensitivity?
Baroreflex sensitivity can be decreased by stiffening of the arterial wall due to disease (e.g., diabetes, hypertension), arteriosclerosis, and aging.
p.12
Baroreceptor Function and Regulation
How do baroreceptors sense pressure?
Baroreceptors sense pressure via changes in stretch (distortion) of the arterial wall.
p.15
Cardiovascular Reflexes and Negative Feedback
What effect does increased sympathetic drive to the kidney have?
It releases renin/angiotensin.
p.15
Cardiovascular Reflexes and Negative Feedback
What is the result of increased vascular resistance due to decreased arterial pressure?
Intense vasoconstriction in the skin, intermediate vasoconstriction in the kidney, intestine, and skeletal muscle, and least vasoconstriction in the heart and brain.
p.8
Angina Pectoris Types and Features
What is Prinzmetal (Variant, Vasospastic) Angina?
It is a type of angina caused by vasospasm of a major coronary artery.
p.7
Angina Pectoris Types and Features
What is the hallmark feature of typical angina pectoris?
It is predictable and resolves with rest.
p.12
Baroreceptor Function and Regulation
What is the function of arterial baroreceptors?
Baroreceptors convert mechanical (pressure) to electrical (nerve action potentials).
p.12
Baroreceptor Function and Regulation
How do baroreceptors respond to an increase in pressure?
As pressure increases, baroreceptor firing increases.
p.2
Physical Factors Affecting Coronary Flow
How does right ventricular flow change with the onset of contraction?
Right ventricular flow increases with the onset of contraction.
p.12
Baroreceptor Function and Regulation
How can changes in the set point affect blood pressure?
Changes in the set point (e.g., due to disease) can cause a change in blood pressure.
p.3
Physical Factors Affecting Coronary Flow
How does the diastolic interval change with increasing heart rate?
The diastolic interval decreases as heart rate increases.
p.13
Baroreceptor Function and Regulation
Can baroreflex sensitivity and set point be altered?
Yes, baroreflex sensitivity and set point can be altered by disease, aging, drugs, and physiological factors such as exercise.
p.10
Cardiovascular Reflexes and Negative Feedback
What are the principles of negative feedback in cardiovascular regulation?
Negative feedback in cardiovascular regulation involves mechanisms that counteract changes in the body to maintain homeostasis, such as adjusting heart rate and blood vessel diameter in response to blood pressure changes.
p.8
Angina Pectoris Types and Features
What are the hallmark features of Prinzmetal Angina?
It is unpredictable, can occur at rest, and does not respond to rest.
p.7
Angina Pectoris Types and Features
What happens to blood flow during rest in typical angina pectoris?
Adequate flow is maintained at rest.
p.14
Cardiovascular Reflexes and Negative Feedback
What effect does increased sympathetic drive to the kidney have?
It releases renin/angiotensin.
p.14
Cardiovascular Reflexes and Negative Feedback
How does increased renal sympathetic nerve activity affect the kidneys?
It increases salt and water retention, blood volume, and renin release, leading to the synthesis of angiotensin II.
p.12
Baroreceptor Function and Regulation
What is the set point in the context of baroreceptor function?
The set point is where the reflex is most sensitive and will be most stable.
p.4
Ischemic Heart Disease Pathophysiology
What initiates the pathophysiology of ischemic heart disease?
Deposition of lipid beneath the endothelial lining.
p.8
Angina Pectoris Types and Features
Can Prinzmetal Angina occur in angiographically normal arteries?
Yes, it can occur in angiographically normal arteries.
p.14
Cardiovascular Reflexes and Negative Feedback
What happens to sympathetic nervous system activity when there is a decrease in arterial pressure?
Sympathetic nervous system activity is increased.
p.2
Physical Factors Affecting Coronary Flow
When is total coronary flow the least?
Total coronary flow is the least during systole.
p.12
Baroreceptor Function and Regulation
What happens when the arterial wall is stretched or distorted?
Stretch or distortion of the arterial wall activates the baroreceptors to increase parasympathetic nervous system activity and decrease sympathetic nervous system activity.
p.6
Clinical Indices of Ischemic Heart Disease
What EKG changes are associated with ischemic heart disease?
S-T segment elevation or depression, and T wave inversion.
p.4
Ischemic Heart Disease Pathophysiology
What factors are secreted during the inflammatory response in ischemic heart disease?
Growth promoting and degradative factors.
p.1
Metabolic Regulation of Coronary Blood Flow
What percentage of oxygen extraction occurs in the myocardium?
Approximately 80% of oxygen is extracted in the myocardium.
p.15
Cardiovascular Reflexes and Negative Feedback
What is the effect of decreased capillary hydrostatic pressure on fluid reabsorption?
Reabsorption of fluid increases, leading to an increase in plasma volume.
p.1
Metabolic Regulation of Coronary Blood Flow
How much can coronary flow increase to meet oxygen demand in a normal heart?
Coronary flow can meet a 5-6 fold increase in oxygen demand in a normal heart.
p.3
Metabolic Regulation of Coronary Blood Flow
What effect do metabolic products have on coronary vessels?
They produce vasodilation.
p.7
Angina Pectoris Types and Features
How does the body compensate for increased resistance to blood flow in typical angina pectoris?
By dilation of terminal arterioles downstream.
p.13
Baroreceptor Function and Regulation
What is the effect of carotid sinus massage on baroreceptors?
Carotid sinus massage distorts the carotid baroreceptors, increases vagal discharge, decreases sympathetic discharge, slows AV node conduction, and can interrupt arrhythmias.
p.2
Physical Factors Affecting Coronary Flow
What happens to myocardial blood vessels during systole?
Myocardial blood vessels are compressed during systole due to pressures in the ventricular chambers.
p.6
Angina Pectoris Types and Features
What are the typical symptoms of angina?
Diffuse substernal crushing, suffocating feeling, tightness, and pain that may radiate to the left arm, face, or back.
p.10
Cardiovascular Reflexes and Negative Feedback
What are the major components of the arterial reflex pathway?
The major components of the arterial reflex pathway include arterial baroreceptors, afferent nerves, the medullary cardiovascular center, efferent nerves, and the heart and blood vessels.
p.15
Cardiovascular Reflexes and Negative Feedback
Which tissues experience the least vasoconstriction when arterial pressure decreases?
The heart and brain, due to dominant local factors.
p.10
Cardiovascular Reflexes and Negative Feedback
How does the volume reflex respond to a change in blood volume?
The volume reflex responds to a change in blood volume by adjusting heart rate, blood vessel diameter, and kidney function to counteract the change and maintain stable blood volume.
p.1
Metabolic Regulation of Coronary Blood Flow
What is the dominant factor controlling coronary resistance vessels and coronary blood flow?
Metabolic autoregulation is the dominant factor controlling coronary resistance vessels and coronary blood flow.
p.8
Angina Pectoris Types and Features
What may cause the vasospasm in Prinzmetal Angina?
It may be due to destruction of endothelium and enhanced vasoconstrictor reactivity.
p.7
Angina Pectoris Types and Features
What is coronary steal in the context of typical angina pectoris?
A phenomenon where blood flow is diverted away from the ischemic area, worsening the condition.
p.14
Cardiovascular Reflexes and Negative Feedback
What is the effect of venous constriction in response to decreased arterial pressure?
Venous constriction increases mean circulatory filling pressure (MCFP) and venous return.
p.14
Cardiovascular Reflexes and Negative Feedback
What factors does the arterial baroreceptor reflex control to regulate blood pressure?
It controls venous return, cardiac filling, cardiac function, and cardiac output.
p.10
Baroreceptor Function and Regulation
What is the function of atrial and venous baroreceptors?
Atrial and venous baroreceptors detect changes in blood volume and send signals to the brain to adjust heart rate, blood vessel diameter, and kidney function to maintain stable blood volume.
p.15
Cardiovascular Reflexes and Negative Feedback
What happens to capillary hydrostatic pressure when arterial pressure decreases?
Capillary hydrostatic pressure decreases.
p.4
Ischemic Heart Disease Pathophysiology
What effect does increased oxidative stress have on blood vessels in ischemic heart disease?
It contributes to endothelial cell damage and enhanced constriction/vasospasm.
p.5
Plaque Characteristics: Hard vs. Soft Plaque
What characterizes hard plaque in coronary arteries?
Growth exceeds degradation, inward remodeling, thick fibrous cap, less prone to fissure/rupture, greater lumen occlusion, and angina.
p.13
Baroreceptor Function and Regulation
What is baroreflex resetting?
Baroreflex resetting is the adaptation of baroreceptors to a new pressure, where the baroreceptor reflex will defend pressure around the new set point value.
p.10
Baroreceptor Function and Regulation
What is the function of arterial baroreceptors?
Arterial baroreceptors detect changes in arterial pressure and send signals to the brain to adjust heart rate and blood vessel diameter to maintain stable blood pressure.
p.9
Myocardial Infarction and Cardiac Enzymes
What is a myocardial infarction?
Ischemia of sufficient duration and severity to result in tissue damage.
p.9
Myocardial Infarction and Cardiac Enzymes
What are the characteristics of cardiac troponins T and I?
They are not present in other tissues (high specificity), not normally found in plasma (high sensitivity), released 4-6 hours after infarct, and remain elevated for up to 7-14 days after the initial infarct.
p.1
Metabolic Regulation of Coronary Blood Flow
What effect does lactate from glycolysis have on blood vessels?
Lactate from glycolysis acts as a vasodilator.
p.14
Cardiovascular Reflexes and Negative Feedback
How does the heart respond to a decrease in arterial pressure?
There is a decrease in parasympathetic activity and an increase in sympathetic nervous system activity, leading to an increase in heart rate and cardiac contractility.
p.2
Physical Factors Affecting Coronary Flow
When is total coronary flow the greatest?
Total coronary flow is the greatest during diastole.
p.6
Angina Pectoris Types and Features
What are some atypical symptoms of angina?
Epigastric burning, sweating, dizziness, fatigue, nausea, and dyspnea.
p.4
Ischemic Heart Disease Pathophysiology
What are the consequences of atherosclerotic plaque formation?
Increased vascular resistance, endothelial cell damage, increased oxidative stress, loss of nitric oxide, and enhanced constriction/vasospasm.
p.1
Metabolic Regulation of Coronary Blood Flow
What effect does adenosine have on blood vessels?
Adenosine acts as a vasodilator.
p.9
Myocardial Infarction and Cardiac Enzymes
What can a second peak in CPK-MB levels indicate?
It can detect multiple infarcts.
p.2
Physical Factors Affecting Coronary Flow
How does left ventricular flow change with the onset of contraction?
Left ventricular flow decreases with the onset of contraction and has a slight rebound during systole.
p.2
Physical Factors Affecting Coronary Flow
When does left ventricular flow peak?
Left ventricular flow peaks during diastole.
p.6
Ischemic Heart Disease Pathophysiology
What is silent ischemia?
Myocardial ischemia without angina.
p.1
Metabolic Regulation of Coronary Blood Flow
How does the capillary density in the heart compare to that in skeletal muscle?
The capillary density in the heart is approximately three times that of skeletal muscle.
p.12
Baroreceptor Function and Regulation
What are the effects of baroreceptor activation on heart rate, cardiac output, vascular resistance, and blood pressure?
Baroreceptor activation decreases heart rate, cardiac output, vascular resistance, and blood pressure.
p.6
Angina Pectoris Types and Features
What symptoms do women more often report with angina?
Back pain, jaw pain, dyspnea, nausea, and fatigue.
p.15
Cardiovascular Reflexes and Negative Feedback
Where is blood flow directed when arterial pressure decreases?
To critical tissues such as the brain and heart.
p.15
Cardiovascular Reflexes and Negative Feedback
What happens to sympathetic nervous system activity when arterial pressure decreases?
Sympathetic nervous system activity is increased.
p.4
Ischemic Heart Disease Pathophysiology
What type of response is triggered by lipid deposition in ischemic heart disease?
A local inflammatory response involving inflammatory cells.
p.4
Ischemic Heart Disease Pathophysiology
What characterizes the cycles of growth and degradation in ischemic heart disease?
They occur around a central lipid core.
p.10
Cardiovascular Reflexes and Negative Feedback
What are the major components of the volume reflex pathway?
The major components of the volume reflex pathway include atrial and venous baroreceptors, afferent nerves, the medullary cardiovascular center, efferent nerves, and the kidneys.
p.1
Metabolic Regulation of Coronary Blood Flow
What is the myocardial oxygen consumption (MVO2) like at rest?
Myocardial oxygen consumption (MVO2) is very high even at rest.
p.9
Myocardial Infarction and Cardiac Enzymes
How long do cardiac troponins T and I remain elevated after a myocardial infarction?
Up to 7-14 days after the initial infarct.
p.10
Cardiovascular Reflexes and Negative Feedback
How does the arterial baroreflex respond to a change in arterial pressure?
The arterial baroreflex responds to a change in arterial pressure by adjusting heart rate and blood vessel diameter to counteract the change and maintain stable blood pressure.
p.1
Metabolic Regulation of Coronary Blood Flow
What is the relationship between coronary oxygen demand and coronary blood flow?
There is a tight coupling between coronary oxygen demand and coronary blood flow via metabolic autoregulation of terminal arteriole resistance vessels.
p.1
Metabolic Regulation of Coronary Blood Flow
What does a coronary flow reserve (CFR) of less than 2 indicate?
A coronary flow reserve (CFR) of less than 2 indicates that the heart is prone to ischemia.
p.4
Plaque Characteristics: Hard vs. Soft Plaque
What is an atherosclerotic plaque composed of?
A soft central core overlaid with a stiff fibrous cap.
p.1
Metabolic Regulation of Coronary Blood Flow
What are the main mediators of metabolic autoregulation in coronary circulation?
The main mediators are decreased oxygen (pO2), increased CO2 (pCO2), opening of K channels, and adenosine.
p.15
Cardiovascular Reflexes and Negative Feedback
What is the formula for blood pressure (BP)?
BP = CO x TPR (Blood Pressure = Cardiac Output x Total Peripheral Resistance).
p.1
Metabolic Regulation of Coronary Blood Flow
What effect does CO2 have on blood vessels?
CO2 acts as a vasodilator.
p.4
Ischemic Heart Disease Pathophysiology
What happens to nitric oxide levels in the presence of atherosclerotic plaques?
There is a loss of nitric oxide.
p.9
Myocardial Infarction and Cardiac Enzymes
How does the pain of a myocardial infarction compare to severe angina?
The pain/feeling is similar to severe angina but the duration is much longer and does not resolve with rest.
p.9
Myocardial Infarction and Cardiac Enzymes
What are cardiac enzyme levels used for in the context of myocardial infarction?
They are an index of tissue damage.
p.9
Myocardial Infarction and Cardiac Enzymes
When is CPK-MB released after a myocardial infarction?
4-6 hours after the infarct.
p.1
Metabolic Regulation of Coronary Blood Flow
How does oxygen act in the body, excluding the lungs?
Oxygen acts as a vasoconstrictor everywhere but the lungs.
p.9
Myocardial Infarction and Cardiac Enzymes
What is the significance of Creatine Phosphokinase (CPK-MB) in myocardial infarction?
CPK-MB is more specific for cardiac muscle, released 4-6 hours after infarct, and returns to normal in about 48 hours.
