2S_1_SYSTEMIC ARTERIAL HYPERTENSION (PART 1)

A major risk factor for atherosclerotic cardiovascular disease (ASCVD)

SYSTEMIC ARTERIAL HYPERTENSION

involve the heart or blood vessel of the circulatory system that would take its root or cause from Atherosclerosis

Atherosclerotic cardiovascular disease

is the process by which we form and deposits cholesterol plaques in arterial walls

Atherosclerosis

SYSTEMIC ARTERIAL HYPERTENSION:

Many patients with hypertension are __ diagnosed

NOT

SYSTEMIC ARTERIAL HYPERTENSION:

remains a major contributor of CAD, CHF, CVD and ESRD

High BP

SYSTEMIC ARTERIAL HYPERTENSION:

accelerates atherogenesis and and increases the risk of cardiovascular events

High BP

SYSTEMIC ARTERIAL HYPERTENSION:

Levels of ___ & ___ are associated with cardiovascular events in a continuously graded and apparently independent fashion

Levels of SBP and DBP

T OR F: Both elevated SBP and DBP are dangerous

TRUE

ELEVATED SBP & DBP:

tend to develop strokes

Elevated SBP (more elevated than DBP)

• higher chance of blood vessels popping due to high pressure

ELEVATED SBP & DBP:

pushes the patient more towards heart attacks or myocardial infarction

Elevated DBP

•  (heart goes hungry) no blood goes in it causing a heart attack.

SYSTEMIC ARTERIAL HYPERTENSION:

occurs in association with other atherogenic factors including:

1. D___ia

2. G___e Intolerance

3. Hyp___ia

4. O___y

1. Dyslipidemia

2. Glucose Intolerance

3. Hyperinsulinemia

4. Obesity

SYSTEMIC ARTERIAL HYPERTENSION:

occurs in association with other atherogenic factors including:

Abnormal levels in lipid levels (high bad cholesterol, low good cholesterol, high triglycerides)

Dyslipidemia

SYSTEMIC ARTERIAL HYPERTENSION:

occurs in association with other atherogenic factors including:

range from pre-diabetes to diabetes; general term for sugar problems that would later on lead to diabetes

Glucose Intolerance

SYSTEMIC ARTERIAL HYPERTENSION:

occurs in association with other atherogenic factors including:

related to glucose intolerance → later lead to DM

Hyperinsulinemia

SYSTEMIC ARTERIAL HYPERTENSION:

Association with other risk factors is __ rather than additive

multiplicative

SYSTEMIC ARTERIAL HYPERTENSION:

Most patients with HTN have __ symptoms attributable to high BP

NO SX = asymptomatic

SYSTEMIC ARTERIAL HYPERTENSION:

CAD is approximately __ as prevalent in hypertensives as in normotensive person of same age

TWICE

SYSTEMIC ARTERIAL HYPERTENSION:

Factors that contribute to the increase risk of CHD associated with high BP:

1. Accelerated n___g of e___al arteries

2. C___y a___r hypertrophy

3. Reduced m___l v___ity

4. P___ar f___s

1. Accelerated narrowing of epicardial arteries

2. Coronary arteriolar hypertrophy

3. Reduced myocardial vascularity

4. Perivascular fibrosis

SYSTEMIC ARTERIAL HYPERTENSION:

Factors that contribute to the increase risk of CHD associated with high BP:

Epicardial arteries become narrow when Htn is present which is accelerated by increasing BP levels

Accelerated narrowing of epicardial arteries

SYSTEMIC ARTERIAL HYPERTENSION:

Factors that contribute to the increase risk of CHD associated with high BP:

Hypertrophy of arteriolar vessels of the heart

Coronary arteriolar hypertrophy

SYSTEMIC ARTERIAL HYPERTENSION:

Factors that contribute to the increase risk of CHD associated with high BP:

Less food/blood circulating in heart d/t Htn

Reduced myocardial vascularity

SYSTEMIC ARTERIAL HYPERTENSION:

Factors that contribute to the increase risk of CHD associated with high BP:

Htn promotes inflammation — Fibrosis is the end of inflammation

Perivascular fibrosis

DEFINITIONS:

Pressure measured in brachial artery during systole

SYSTOLIC BLOOD PRESSURE (SBP)

DEFINITIONS:

Ventricular emptying and ventricular contraction period

SYSTOLIC BLOOD PRESSURE (SBP)

DEFINITIONS:

1st loudest sound when you release the cuff in BP taking

SYSTOLIC BLOOD PRESSURE (SBP)

DEFINITIONS:

Pressure measured in brachial artery during diastole

DIASTOLIC BLOOD PRESSURE (DBP)

DEFINITIONS:

Ventricular filling and ventricular relaxation

DIASTOLIC BLOOD PRESSURE (DBP)

DEFINITIONS:

It is on the level when you no longer appreciate the sound

DIASTOLIC BLOOD PRESSURE (DBP)

DEFINITIONS: DETERMINANTS OF ARTERIAL PRESSURE:

A___L PRESSURE

• C___C O___T

• P___L R___NCE

ARTERIAL PRESSURE

• CARDIAC OUTPUT

• PERIPHERAL RESISTANCE

DETERMINANTS OF ARTERIAL PRESSURE:

CARDIAC OUTPUT

• S__E V__E

• H__T R__E

• STROKE VOLUME

• HEART RATE

DETERMINANTS OF ARTERIAL PRESSURE:

PERIPHERAL RESISTANCE:

• VASCULAR S___E

• VASCULAR F___N

• VASCULAR STRUCTURE

• VASCULAR FUNCTION

DETERMINANTS OF ARTERIAL PRESSURE:

Product of cardiac output and the peripheral resistance

Arterial Pressure

DETERMINANTS OF ARTERIAL PRESSURE:

Product of the stroke volume and heart rate

Cardiac Output

DETERMINANTS OF ARTERIAL PRESSURE:

Amount of the blood each time the heart pumps

Stroke Volume

DETERMINANTS OF ARTERIAL PRESSURE:

The more amount of blood that the heart ejects, the higher would be the s___ v____ is

Stroke Volume

DETERMINANTS OF ARTERIAL PRESSURE:

Higher heart rate = the BP would also be higher

Stroke Volume

DEFINITIONS:

"average" pressure throughout the cardiac cycle against the walls of the proximal systemic arteries (aorta)

MEAN ARTERIAL PRESSURE (MAP)

DEFINITIONS:

estimated as: 1/3 (SBP + 2DBP)

MEAN ARTERIAL PRESSURE (MAP)

DEFINITIONS:

Employed on patients with stroke: If pt develops stroke d/t Htn, ischemic stroke d/t elevated BP (ex. 200/120) → do not bring down BP right away → maintain the MAP (bringing the BP slowly)

MEAN ARTERIAL PRESSURE (MAP)

• d/t concept of ischemic penumbra; it might get compromised if brought down quickly

DEFINITIONS:

MAP: area around the infarcted side that is still salvageable but high risk of being infarcted

Ischemic penumbra

DEFINITIONS:

MAP: Protect P___ by maintaining the blood flow circulation in the area, you can only do that if you elevate the BP or allow High BP

penumbra

• Remember: need some pressure to drive blood into an area, that is why you do not bring the BP right away in stroke pts (particularly ischemic strokes)

DEFINITIONS:

the sum of all forces that oppose blood flow

TOTAL PERIPHERAL RESISTANCE (TPR)

PRINCIPAL MECHANISMS:

1. I__R VOLUME

2. A__C N__S SYSTEM

3. R__ SYSTEM

4. V__R MECHANISMS

1. INTRAVASCULAR VOLUME

2. AUTONOMIC NERVOUS SYSTEM

3. RAA SYSTEM

4. VASCULAR MECHANISMS

PRINCIPAL MECHANISMS:

Amount of volume inside blood vessels

INTRAVASCULAR VOLUME

PRINCIPAL MECHANISMS:

Alterations in total extracellular fluid volume are associated with proportional changes of blood volume

INTRAVASCULAR VOLUME

PRINCIPAL MECHANISMS: INTRAVASCULAR VOLUME:

is a primary determinant of the extracellular fluid volume

SODIUM

• Where sodium goes water goes/ sodium attracts water

• When NaCl intake exceeds the capacity of the kidney to excrete sodium, vascular volume initially expands and cardiac output increases

PRINCIPAL MECHANISMS:

Maintains cardiovascular homeostasis

AUTONOMIC NERVOUS SYSTEM

PRINCIPAL MECHANISMS:

Controls all the involuntary things in the body

AUTONOMIC NERVOUS SYSTEM

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Controls all the involuntary things in the body:

1. B___ P___ure

2. V___e

3. Ch___or signals

1. Blood Pressure

2. Volume

3. Chemoreceptor signals

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Three endogenous catecholamines (Fight or flight hormones):

1. Norepinephrine

2. Epinephrine

3. Dopamine

1. Norepinephrine

2. Epinephrine

3. Dopamine

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

modulate blood pressure over the short term

Adrenergic reflexes

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

contributes to the long-term regulation of arterial pressure

Adrenergic function + hormonal and volume related factors factors

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Receptors that perceive the pressure

BARORECEPTORS

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Several reflexes modulate blood pressure on a minute-to-minute basis

BARORECEPTORS

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Stretch-sensitive sensory nerve endings located in the carotid sinuses and the aortic arch

BARORECEPTORS

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

rate of firing of these baroreceptors (INCREASES OR DECREASES) with arterial pressure

INCREASES

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

BARORECEPTORS: is a decrease of sympathetic outflow, resulting in decreases of arterial pressure and heart rate.

NET EFFECT

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

primary mechanism for rapid buffering of acute fluctuations of arterial pressure that may occur during postural changes, behavioral or physiological stress, and changes in blood volume

BARORECEPTORS

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Response: cascade of events that would bring down BP eventually and normalize it if BP increases (minute-to-minute basis)

BARORECEPTORS

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Activity of the baroreflex d___ or a___s to sustained increases of arterial pressure

decline or adapts

PRINCIPAL MECHANISMS: AUTONOMIC NERVOUS SYSTEM:

Patients with autonomic neuropathy and impaired baroreflex function may have extremely l___ blood pressures with difficulty to control e___ b___ p___ s___

labile blood pressures with difficulty to control episodic blood pressure spikes

• Elderly or diabetic pt or problem with nervous system → they cannot sense changes in position → baroreceptors are not working.

PRINCIPAL MECHANISMS:

RAA system meaning

Renin Angiotensin Aldosterone system

PRINCIPAL MECHANISMS:

RAA SYSTEM: Synthesized in the segment of the renal afferent renal arteriole JG Cells (juxtaglomerular cells) that abuts the glomerulus and a group of sensory cells located at the distal end of the loop of Henle, the macula densa

RENIN

PRINCIPAL MECHANISMS:

RAA SYSTEM: contributes to the regulation of arterial pressure primarily via the vasoconstrictor properties of angiotensin II and the sodium-retaining properties of aldosterone

RENIN

PRINCIPAL MECHANISMS:

RAA SYSTEM: 3 PRIMARY STIMULI FOR RENIN SECRETION:

1. ↓ NaCl transport in the thick ascending limb of the loop of Henle (macula densa mechanism)

2. ↓ pressure or stretch within the renal afferent arteriole (baroreceptor mechanism)

3. Sympathetic nervous system stimulation of renin-secreting cells via β₁ adrenoreceptors

1. ↓ NaCl transport in the thick ascending limb of the loop of Henle (macula densa mechanism)

2. ↓ pressure or stretch within the renal afferent arteriole (baroreceptor mechanism)

3. Sympathetic nervous system stimulation of renin-secreting cells via β₁ adrenoreceptors

PRINCIPAL MECHANISMS:

RAA SYSTEM: 3 PRIMARY STIMULI FOR RENIN SECRETION:

Lead to hyponatremia (low sodium level); JG cell senses decrease in sodium → renin secretion

↓ NaCl transport in the thick ascending limb of the loop of Henle (macula densa mechanism)

PRINCIPAL MECHANISMS:

RAA SYSTEM: 3 PRIMARY STIMULI FOR RENIN SECRETION:

Less fluid entering the kidney (e.g. dehydration) → detected by JG cells → renin secretion

↓ pressure or stretch within the renal afferent arteriole (baroreceptor mechanism)

PRINCIPAL MECHANISMS:

RAA SYSTEM: 3 PRIMARY STIMULI FOR RENIN SECRETION:

Nervousness, agitation stimulates renin

Sympathetic nervous system stimulation of renin-secreting cells via β1 adrenoreceptors

PRINCIPAL MECHANISMS:

RAA SYSTEM: A potent vasoconstrictor

ANGIOTENSIN II

PRINCIPAL MECHANISMS:

RAA SYSTEM: In response to low renal arterial pressure or low concentration of filtered sodium in kidneys

ANGIOTENSIN II

PRINCIPAL MECHANISMS:

RAA SYSTEM: ANGIOTENSIN II:

↑ BP

• ↑ intracellular c___/blood vessel wall c___n

• ↑ s___c nervous system activity

• stimulates v___n release

• stimulates a___ne

• ↑ intracellular calcium/blood vessel wall constriction

• ↑ sympathetic nervous system activity

• stimulates vasopressin release

• stimulates aldosterone

PRINCIPAL MECHANISMS:

RAA SYSTEM: A potent mineralocorticoid that increases sodium reabsorption

ALDOSTERONE

PRINCIPAL MECHANISMS:

RAA SYSTEM: Promotes water retention

ALDOSTERONE

PRINCIPAL MECHANISMS:

RAA SYSTEM: Enhance extracellular matrix and collagen deposition within the myocardium

ALDOSTERONE

PRINCIPAL MECHANISMS:

RAA SYSTEM: Stimulate cardiac fibrosis and left ventricular hypertrophy

ALDOSTERONE

PRINCIPAL MECHANISMS:

RAA SYSTEM: May also cause glomerular hyperfiltration and albuminuria

ALDOSTERONE

PRINCIPAL MECHANISMS:

Ability of blood vessel to relax, dilate & constrict

VASCULAR MECHANISMS

PRINCIPAL MECHANISMS:

Vascular radius and compliance of resistance arteries are also important determinants of arterial pressure

VASCULAR MECHANISMS

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS

resistance to flow varies (DIRECTLY OR INVERSELY) with the fourth power of the radius

INVERSELY

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS:

consequently small decreases in lumen size significantly (INCREASE OR DECREASE) resistance

INCREASE

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS:

In h____e patients, structural, mechanical, or functional changes may reduce lumen diameter of small arteries and arterioles

hypertensive

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS:

Changes in the component or structure of the blood vessels

REMODELING

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS:

refers to geometric alterations in the vessel wall without changing vessel volume

REMODELING

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS:

results in ↓ lumen size, ↑ peripheral resistance

REMODELING

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

1. H___C REMODELING

2. E___IC REMODELING

1. HYPERTROPHIC REMODELING

2. EUTROPHIC REMODELING

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

increased cell number, increased cell size, and increased deposition of intercellular matrix

Hypertrophic Remodeling

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

no change in the amount of material in the vessel wall; just becomes rigid

Eutrophic Remodeling

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

also contribute to remodeling:

1. A___s

2. l___-grade in___n

3. va___r fi___s

1. Apoptosis

2. low-grade inflammation

3. vascular fibrosis

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

also contribute to remodeling:

programmed cell death

Apoptosis

PRINCIPAL MECHANISMS: VASCULAR MECHANISMS: REMODELING:

is also related to elasticity of the vessel

LUMEN DIAMETER

OTHER REGULATORS OF CARDIAC FUNCTIONS: DURING EXERCISE:

• ↓ parasympathetic

• ↑ sympathetic stimulation

• ↑ SV, HR, CO

• ↑ venous return (sympathetic and muscle pumping)

• ↓ parasympathetic

• ↑ sympathetic stimulation

• ↑ SV, HR, CO

• ↑ venous return (sympathetic and muscle pumping)

OTHER REGULATORS OF CARDIAC FUNCTIONS: DURING EXERCISE:

In the periphery, CO is redistributed to favor working muscles

periphery

• Job of sympathetic: provide blood to the muscles, increase function to the lungs

OTHER REGULATORS OF CARDIAC FUNCTIONS: DURING EXERCISE:

• Local metabolites dilate arterioles

• ↑ regional blood flow

• Local metabolites dilate arterioles

• ↑ regional blood flow

Regional not SYSTEMIC, ↑ in blood flow only in areas that are needed

Sympathetic vasoconstriction in non working areas

Sympathetic vasoconstriction

• Job of sympathetic system

• Sympathetic system knows where to prioritize blood circulation

OTHER REGULATORS OF CARDIAC FUNCTIONS: DURING EXERCISE:

• Modest ↑ SBP, no change in DBP

• Mean BP is constant or slightly elevated

• Significantly ↓ systemic vascular resistance

• Oxygen consumption 20x

• Modest ↑ SBP, no change in DBP

• Mean BP is constant or slightly elevated

• Significantly ↓ systemic vascular resistance

• Oxygen consumption 20x

CLASSIFICATION:

1. E____L HTN (P____Y)

2. S____RY HTN

1. ESSENTIAL HTN (PRIMARY)

2. SECONDARY HTN

CLASSIFICATION: Elevated BP without a cause

ESSENTIAL HTN

CLASSIFICATION: Due to aging

ESSENTIAL HTN

CLASSIFICATION: Same as to Primary HTN

ESSENTIAL HTN

CLASSIFICATION: tends to be familial and is likely to be the consequence of an interaction between environmental and genetic factors

ESSENTIAL HTN