Antihypertensive Drugs Flashcards
(120 cards)
1
Q
What is the most common cardiovascular disease?
A
Hypertension
2
Q
Does hypertension affect all population groups equally?
A
No, prevalence varies with age, race, education, and other factors
3
Q
By what age do 60–80% of people develop hypertension?
A
By age 80
4
Q
What organs are commonly damaged by sustained hypertension?
A
Kidneys, heart, and brain
5
Q
What are the complications of long-term hypertension?
A
Renal failure, coronary artery disease, heart failure, stroke, and dementia
6
Q
Can lowering blood pressure prevent organ damage?
A
Yes, effective pharmacologic treatment can prevent vessel damage and reduce disease and death rates
7
Q
Why is understanding the mechanism and site of action of antihypertensive drugs important?
A
It helps predict efficacy and possible side effects
8
Q
What does rational use of antihypertensive drugs mean?
A
Using the right drug(s), alone or in combination, based on patient needs to control BP effectively and safely
9
Q
What is required for the diagnosis of hypertension?
A
Repeated, reproducible measurements of elevated blood pressure.
10
Q
What does the diagnosis of hypertension predict?
A
It predicts the consequences and risks for the patient, not necessarily the cause.
11
Q
How is the risk of damage to organs related to blood pressure?
A
The risk of damage to the kidney, heart, and brain increases directly with the elevation of blood pressure.
12
Q
Does mild hypertension (140/90 mmHg) increase the risk of organ damage?
A
Yes, even mild hypertension increases the risk of eventual end-organ damage.
13
Q
How does cardiovascular disease risk change with blood pressure starting at 115/75 mmHg?
A
Risk doubles with each increment of 20/10 mmHg throughout the blood pressure range
14
Q
What is the impact of isolated systolic hypertension?
A
It is not benign and is still associated with end-organ damage.
15
Q
How does the urgency of therapy relate to blood pressure elevation?
A
The higher the blood pressure, the more urgent it is to initiate therapy
16
Q
In which group is the risk of end-organ damage higher at any blood pressure level?
A
The risk is higher in African Americans.
17
Q
How does the risk of end-organ damage in premenopausal women compare to men?
A
It is relatively lower in premenopausal women than in men
18
Q
What are some positive risk factors for hypertension and end-organ damage?
A
Smoking, metabolic syndrome (obesity, dyslipidemia, diabetes), manifestations of end-organ damage, and a family history of cardiovascular disease.
19
Q
Can hypertension be diagnosed based on symptoms reported by the patient?
A
No, hypertension is diagnosed based on blood pressure measurement, not symptoms
20
Q
When do symptoms of hypertension typically appear?
A
Symptoms usually appear when overt end-organ damage is imminent or has already occurred.
21
Q
What is essential or primary hypertension?
A
Hypertension with no specific cause identified.
22
Q
What is secondary hypertension?
.
A
Hypertension caused by a specific underlying medical condition
23
Q
Why is it important to consider specific causes in each case of hypertension?
A
Because some causes are treatable with definitive surgical treatment.
24
Q
What are some conditions that can cause secondary hypertension and may be treated with surgery?
A
Renal artery constriction, coarctation of the aorta, pheochromocytoma, Cushing’s disease, and primary aldosteronism
25
What is renal artery constriction?
Narrowing of the arteries supplying the kidneys, which can affect blood pressure.
26
What is coarctation of the aorta?
A narrowing of the aorta that affects blood flow and increases blood pressure.
27
What is pheochromocytoma?
A tumor in the adrenal glands that secretes hormones, leading to increased blood pressure.
28
What is Cushing’s disease?
A condition where the body produces too much cortisol, leading to high blood pressure.
29
What is primary aldosteronism?
Overproduction of aldosterone, which increases sodium retention and raises blood pressure.
30
What is typically responsible for elevated blood pressure in most cases?
An increase in resistance to the flow of blood through arterioles.
31
Is cardiac output usually affected in hypertension?
No, cardiac output is usually normal in hypertension.
32
What has failed to identify a single cause of increased peripheral vascular resistance in essential hypertension?
Investigations of the autonomic nervous system, baroreceptor reflexes, the renin-angiotensin-aldosterone system, and the kidneys.
33
What is the cause of elevated blood pressure in most cases of essential hypertension?
A combination of several (multifactorial) abnormalities.
34
What factors contribute to the development of hypertension according to epidemiologic evidence?
Genetic factors, psychological stress, environmental factors, and dietary factors (such as increased salt intake and decreased potassium or calcium intake).
35
How does aging affect blood pressure in populations with low daily sodium intake?
Blood pressure increase with aging does not occur in populations with low daily sodium intake.
36
What is labile hypertension?
Hypertension that fluctuates (goes up and down).
37
How are patients with labile hypertension different from normal controls when it comes to salt intake?
They are more likely to have blood pressure elevations after salt loading
38
What is the heritability % of essential hypertension?
About 30%.
39
Which genes are linked to some cases of essential hypertension?
Angiotensinogen, angiotensin-converting enzyme (ACE), β2 adrenoceptor, and α adducin
40
What is the role of the angiotensinogen gene in hypertension?
It regulates blood pressure through the renin-angiotensin system.
41
What is the function of the angiotensin-converting enzyme (ACE) gene?
It regulates blood pressure, especially in handling sodium.
42
How does the β2 adrenoceptor gene affect blood pressure?
It influences how the body responds to hormones like adrenaline, which affect blood pressure.
43
What is the role of α adducin?
It is a protein involved in cell structure, particularly in the kidneys, which can impact blood pressure regulation.
44
What is the hydraulic equation for blood pressure?
BP = CO × PVR.
45
What does BP stand for in the hydraulic equation?
Arterial blood pressure.
46
What is cardiac output (CO)?
The amount of blood the heart pumps per minute.
47
What is peripheral vascular resistance (PVR)?
The resistance blood faces as it moves through precapillary arterioles.
48
How does an increase in cardiac output (CO) affect blood pressure?
It increases blood pressure.
49
What are the main sites where blood pressure is regulated?
Arterioles, postcapillary venules (capacitance vessels), and the heart.
50
What is the role of the kidney in blood pressure regulation?
The kidney regulates blood pressure by controlling the volume of intravascular fluid.
51
What do baroreflexes do?
Baroreflexes regulate blood pressure by adjusting the heart and blood vessels, mediated by the autonomic nervous system.
52
What is the role of humoral mechanisms in blood pressure regulation?
Humoral mechanisms, including the renin-angiotensin-aldosterone system, help maintain blood pressure by influencing fluid balance and vascular resistance.
53
Which system helps coordinate blood pressure regulation at multiple control sites?
The renin-angiotensin-aldosterone system
54
What is the function of vasoactive substances released by the vascular endothelium?
Vasoactive substances help regulate vascular resistance by constricting or dilating blood vessels.
55
What does nitric oxide do to blood vessels?
It dilates blood vessels, lowering blood pressure.
56
What does endothelin-1 do to blood vessels?
It constricts blood vessels, raising blood pressure.
57
How is blood pressure controlled physiologcally in hypertensive patients?
It is controlled by the same mechanisms that are operative in normotensive subjects.
58
How does blood pressure regulation in hypertensive patients differ from normotensive individuals?
In hypertensive patients, baroreceptors and the renal blood volume-pressure control systems are "set" at a higher level of blood pressure.
59
What are baroreceptors responsible for in regulating blood pressure?
Baroreceptors detect changes in blood pressure and adjust the heart rate and vessel tone accordingly.
60
How are the baroreceptors set in hypertensive patients?
In hypertensive patients, the baroreceptors are set to tolerate and maintain a higher level of blood pressure.
61
What is the role of the renal blood volume-pressure control system?
The kidneys regulate blood volume to help control blood pressure.
62
How is the renal blood volume-pressure control system set in hypertensive patients?
In hypertensive patients, the renal blood volume-pressure control system is set to maintain a higher level of blood pressure.
63
How do antihypertensive drugs work?
Antihypertensive drugs interfere with normal blood pressure regulation mechanisms to lower blood pressure
64
What are baroreflexes responsible for?
Baroreflexes are responsible for rapid, moment-to-moment adjustments in blood pressure.
65
What is an example of a situation where baroreflexes act?
Baroreflexes act during a transition from a reclining position to an upright posture.
66
What is the role of central sympathetic neurons in blood pressure regulation?
Central sympathetic neurons, arising from the vasomotor area of the medulla, are tonically active and help regulate blood pressure.
67
How do carotid baroreceptors detect changes in blood pressure?
Carotid baroreceptors are stimulated by the stretch of vessel walls caused by internal pressure (arterial blood pressure).
68
What happens when baroreceptors are activated by high blood pressure?
Baroreceptor activation inhibits central sympathetic discharge, lowering sympathetic activity.
69
What occurs when there is a reduction in arterial pressure or wall stretch?
A reduction in arterial pressure or wall stretch leads to reduced baroreceptor activity, which disinhibits sympathetic discharge, increasing sympathetic activity.
70
How does baroreflex work when transitioning to an upright posture?
When transitioning to an upright posture, blood pools in the veins, reducing blood pressure. This results in decreased wall stretch, which increases sympathetic outflow to restore normal blood pressure.
71
What effect does sympathetic outflow have on blood vessels and the heart?
Sympathetic outflow causes constriction of arterioles (increasing peripheral resistance), stimulation of the heart (increasing cardiac output), and constriction of capacitance vessels (increasing venous return to the heart)
72
What other events can trigger the baroreflex to act?
The baroreflex acts in response to events that lower arterial pressure, including a reduction in peripheral vascular resistance or a reduction in intravascular volume (e.g., hemorrhage or loss of salt and water).
73
How does the baroreflex help restore blood pressure when peripheral resistance or intravascular volume is reduced?
The baroreflex increases sympathetic activity to restore blood pressure when peripheral resistance or intravascular volume is reduced
74
What is the kidney’s role in blood pressure control?
The kidney is primarily responsible for long-term blood pressure control by regulating blood volume.
75
What happens when renal perfusion pressure decreases?
A decrease in renal perfusion pressure causes intrarenal redistribution of blood flow and increased reabsorption of salt and water.
76
How does decreased pressure in renal arterioles affect the kidneys?
Decreased pressure in renal arterioles and sympathetic neural activity stimulate the production of renin.
77
What role does renin play in blood pressure regulation?
Renin triggers the renin-angiotensin-aldosterone system (RAAS), which increases blood pressure by constricting blood vessels and increasing sodium retention.
78
What is the effect of angiotensin II on blood vessels?
Angiotensin II causes direct constriction of resistance vessels, increasing vascular resistance and raising blood pressure.
79
How does angiotensin II contribute to blood pressure regulation?
Angiotensin II stimulates aldosterone synthesis in the adrenal cortex, which increases renal sodium absorption and intravascular blood volume.
80
What role does aldosterone play in blood pressure control?
Aldosterone increases sodium retention by the kidneys, which helps raise blood volume and blood pressure.
80
How does vasopressin help maintain blood pressure?
Vasopressin, released from the posterior pituitary gland, regulates water reabsorption by the kidneys, which helps maintain blood pressure.
81
Where is vasopressin released from, and what is its function?
Vasopressin is released from the posterior pituitary gland and helps regulate water reabsorption by the kidneys, increasing blood volume and blood pressure.
82
What do all antihypertensive agents have in common?
All antihypertensive agents act at one or more of the four anatomical control sites that regulate blood pressure.
83
What are the four anatomical control sites involved in blood pressure regulation?
The four anatomical control sites are arterioles, capacitance vessels, the heart, and the kidney
84
How do antihypertensive drugs work?
Antihypertensive drugs work by interfering with normal mechanisms of blood pressure regulation, targeting specific sites to lower blood pressure.
85
How are antihypertensive drugs classified?
Antihypertensive drugs are classified based on the principal regulatory site or mechanism on which they act.
86
Why do drugs within the same category have similar side effects?
Drugs within the same category tend to produce a similar spectrum of toxicities because they work through similar mechanisms of action.
87
What is the primary way diuretics lower blood pressure?
Diuretics lower blood pressure by depleting the body of sodium, which reduces blood volume.
88
How does the reduction in blood volume lower blood pressure?
When blood volume decreases, the pressure exerted by the blood on the walls of the blood vessels (blood pressure) decreases as well.
89
What do sympathoplegic agents do to lower blood pressure?
Sympathoplegic agents lower blood pressure by reducing peripheral vascular resistance, inhibiting cardiac function, and increasing venous pooling in capacitance vessels.
90
How do sympathoplegic agents reduce cardiac output?
They reduce cardiac output by inhibiting cardiac function and increasing venous pooling, which reduces the amount of blood returning to the heart.
91
How are sympathoplegic agents further subdivided?
They are subdivided according to their sites of action in the sympathetic reflex arc
92
What do direct vasodilators do to lower blood pressure?
Direct vasodilators lower blood pressure by relaxing vascular smooth muscle, dilating resistance vessels, and increasing capacitance.
93
How do direct vasodilators affect resistance vessels?
Direct vasodilators dilate resistance vessels, reducing the resistance blood faces and lowering blood pressure.
94
How do direct vasodilators increase capacitance?
Direct vasodilators increase the capacity of veins, allowing them to hold more blood, further lowering blood pressure.
95
How do angiotensin-blocking agents lower blood pressure?
Angiotensin-blocking agents lower blood pressure by blocking the production or action of angiotensin, which reduces peripheral vascular resistance and possibly lowers blood volume.
96
What effect do angiotensin-blocking agents have on peripheral vascular resistance?
Angiotensin-blocking agents reduce peripheral vascular resistance by blocking angiotensin, a hormone that constricts blood vessels.
97
Do angiotensin-blocking agents also affect blood volume?
Yes, angiotensin-blocking agents can potentially reduce blood volume, which further contributes to lowering blood pressure.
98
How can combining antihypertensive drugs reduce toxicity?
Combining drugs from different groups may allow for lower doses of each drug, reducing the risk of harmful side effects.
99
What is resistant hypertension?
Resistant hypertension refers to high blood pressure that is difficult to control with a single drug.
100
What is polypharmacy in the context of hypertension?
Polypharmacy refers to the use of multiple drugs from different groups to manage hypertension, particularly resistant hypertension.
101
What is resistant hypertension?
Resistant hypertension refers to high blood pressure that does not respond well to treatment with two drugs.
102
What might be the cause of resistant hypertension in some patients?
.
In some cases, secondary hypertension (due to an underlying health condition) may be the cause of resistant hypertension, but most patients do not have treatable secondary hypertension
103
What should be considered when a patient has resistant hypertension?
Patients with resistant hypertension may require three or more drugs for effective blood pressure control.
104
What is one reason for using polypharmacy in hypertension treatment?
Polypharmacy is used because many hypertension drugs evoke compensatory regulatory mechanisms that can limit their effectiveness.
105
What is a compensatory mechanism in the context of hypertension treatment?
A compensatory mechanism is the body's natural response to a drug that tries to counteract its effects, often reducing the drug's effectiveness.
106
What is the effect of hydralazine in treating hypertension?
Hydralazine is a vasodilator that decreases peripheral vascular resistance, leading to a reduction in blood pressure.
107
What are the compensatory mechanisms triggered by hydralazine?
Hydralazine causes tachycardia (increased heart rate) and salt and water retention, which can increase blood pressure and counteract its effect.
108
What effect does a beta-blocker have when combined with hydralazine?
A beta-blocker prevents tachycardia (increased heart rate) caused by hydralazine, improving blood pressure control.
109
What role does a diuretic (e.g., hydrochlorothiazide) play when combined with hydralazine?
A diuretic helps prevent salt and water retention, which reduces blood volume and helps maintain low blood pressure.
110
How do combining hydralazine, a beta-blocker, and a diuretic affect blood pressure?
Combining these drugs increases the sensitivity of the cardiovascular system to each other’s actions, improving the overall effectiveness in lowering blood pressure.
111
Why is polypharmacy effective in treating hypertension?
Polypharmacy is effective because it combines drugs that counteract the compensatory mechanisms of each other, leading to better blood pressure control.
112
What is the effect of ACE inhibitors on blood pressure?
ACE inhibitors typically lower blood pressure by less than 10 mm Hg.
113
Are ACE inhibitors sufficient to control blood pressure in stage 2 hypertension?
No, ACE inhibitors alone may be inadequate to fully control blood pressure in stage 2 hypertension (blood pressure >160/100 mm Hg).
114
Why are ACE inhibitors still important despite modest blood pressure reduction?
ACE inhibitors have significant long-term benefits, such as preventing or reducing renal disease in diabetic patients and improving heart failure.
115
What long-term benefits do ACE inhibitors provide for diabetic patients?
For diabetic patients, ACE inhibitors help prevent or reduce kidney disease
116
How do ACE inhibitors help patients with heart failure?
ACE inhibitors help reduce the symptoms and improve the condition of heart failure patients over time.
117
What is the main issue discussed regarding the use of certain antihypertensive drugs, specifically β blockers?
The main issue discussed is the toxicity of some effective drugs, such as β blockers, which prevents their use at maximally effective dosages.
118
What is the significance of β blockers in treating patients with a history of myocardial infarction?
β blockers are important for reducing mortality in patients who have had a myocardial infarction and have hypertension.
119
