manifestation of novel social challenges of the …...50% undetected, above 80 the bp decreases)...

Manifestation of Novel Social Challenges of the European Union

in the Teaching Material of

Medical Biotechnology Master’s Programmes

at the University of Pécs and at the University of Debrecen Identification number: TÁMOP-4.1.2-08/1/A-2009-0011

CHARACTERISTICS OF

THE CARDIOVASCULAR

SYSTEM,

ABNORMALITIES AND

DISEASES PART 2

Miklós Székely and Márta Balaskó

Molecular and Clinical Basics of Gerontology – Lecture 9

Manifestation of Novel Social Challenges of the European Union

in the Teaching Material of

Medical Biotechnology Master’s Programmes

at the University of Pécs and at the University of Debrecen Identification number: TÁMOP-4.1.2-08/1/A-2009-0011

TÁMOP-4.1.2-08/1/A-2009-0011

Left ventricular volume (ml) ventricular

filling

isovolumic

contraction

ejection

isovolumic

relaxation

systolic

pressure

ventricular

diastolic

pressure

Volume-pressure diagrams 1

0 50 10

0

15

0

200 250

Ventr

icula

r pre

ssure

(m

mH

g)

0

50

100

150

200

250

SV

Young

TÁMOP-4.1.2-08/1/A-2009-0011

Left ventricular volume (ml)


0 50 10

0

15

0

200 250

Ventr

icula

r pre

ssure

(m

mH

g)

0

50

100

150

200

250

1st case

systolic

pressure

ventricular

diastolic

pressure

SV

TÁMOP-4.1.2-08/1/A-2009-0011


ventricular

diastolic

pressure


0 50 10

0

15

0

200 250

Ventr

icula

r pre

ssure

(m

mH

g)

0

50

100

150

200

250

2nd case

systolic

pressure

SV

TÁMOP-4.1.2-08/1/A-2009-0011


systolic

pressure

ventricular

diastolic

pressure


0 50 10

0

15

0

200 250

Ventr

icula

r pre

ssure

(m

mH

g)

0

50

100

150

200

250

3rd case

SV

TÁMOP-4.1.2-08/1/A-2009-0011


systolic

pressure

ventricular

diastolic

pressure


0 50 10

0

15

0

200 250

Ventr

icula

r pre

ssure

(m

mH

g)

0

50

100

150

200

250

4th case

SV

TÁMOP-4.1.2-08/1/A-2009-0011

Exercise in the elderly

• There is a higher sympathetic tone even at

rest

• Diminished contractility

• Tachycardia develops sooner and easier, but

its maximum is limited

• EDV increases quickly, but here the EDp also

increases significantly

• TPR is higher and grows (both the syst. and

diast. pressures increase quickly)

• Stagnation develops quite early (dyspnoe)

TÁMOP-4.1.2-08/1/A-2009-0011

Maximal heart rate vs. age

Heart rate (bpm)

Trained

Non-trained Mean

Age (years)

200

190

180

170

160

150

140 20 30 40 50 60 70

TÁMOP-4.1.2-08/1/A-2009-0011

• Impaired coronary perfusion have only a small influence on myocardial

function in healthy old people (of course, severe atherosclerosis does

have!)

• Ejection fraction of healthy old women and men does not decrease at rest

(when the end systolic and end diastolic volumes are comparable to those

in young people)

• Stroke volume: SV × heart rate – does not change with age, even in case

of a slight (still physiological) increase in the systolic pressure. (The stroke

volume would rather increase a little.)

• Heart rate: resting heart rate (horizontal position) in healthy men is not

age-dependent. The respiration-induced changes in heart rate decrease

though. The increase of the heart-rate is age-dependent: 220-age (The

elderly responds to the same stress with smaller increase in heart rate -

120-130 frequency is already submaximal tachycardia)

• Intrinsic sinus rhythm (by symp. and parasymp. blockade)-significantly

decreased with age: at 20-y it is104/min, at 45-55-y 92/min

Age-related alterations in major

cardiac parameters

TÁMOP-4.1.2-08/1/A-2009-0011

4-5

Tim

e (

min

ute

s)

Endurance times according to age

Maximal oxygen consumption and

endurance times according to age

male female

Maximal oxygen consumption vs. age

VO

2 m

ax (

l/m

in)

6-7 8-9 10-12 14-15 16-18 25 35 45 55 65

5

6

7

8

9

10

11

12

13

0 10 20 30 40 50 60 70 Age (years) Age (years)

1.0

2.0

3.0

4.0

0.0

TÁMOP-4.1.2-08/1/A-2009-0011

Atherosclerosis

• One of the most significant diseases of the

elderly

• Clinical picture includes: pectoral angina, AMI,

TIA, stroke, dementia, arteriosclerosis

obliterans

TÁMOP-4.1.2-08/1/A-2009-0011

Risk factors of atherosclerosis 1

Intrinsic risk factors

• Age: male 45, female above 55 years

• Gender: estrogen provides some protection

(TG, lower LDL cholesterol, higher HDL), after

menopausa the protection diappears: by the

age of 60 the risks of the females exceed the

risks of the male

• Genetic factors: familial appearance, inherited

disorders of the lipid metabolism

TÁMOP-4.1.2-08/1/A-2009-0011

Risk factors of atherosclerosis 2

Extrinsic risk factors

• Smoking (a pack a day increases the risk 2×)

• Hypertension

• Dyslipoproteinemia

• Hyperglycemia, diabetes mellitus

• Obesity

• Homocystinuria

• Hyperuricemia

TÁMOP-4.1.2-08/1/A-2009-0011

Regulation

• The sensitivity of the baroreceptor reflex decreases

(hypertension or orthostatic hypotension)

• The serum levels of the catecholamines increase (increased

release, diminished elimination)

• The efficacy of the sympathetic tone decreases

• The carotids are more rigid (cardiovagal reflex decreases)

• Vestibulosympathic reflex efficacy also decreases (adaptation

to gravitational forces) – orthostatic hypotension (upon

standing up a blood pressure fall greater than 20 mmHg)

• The venes are more rigid – decreased CVP (decreased

venous stagnation)

• The activity of the plasma renin decreases

TÁMOP-4.1.2-08/1/A-2009-0011

Pectoral angina

• Above 70 years the prevalence of coronary

heart disease reaches 70%

• The prevalence of “silent ischemia” increases,

especially in females and in diabetics

(autonomic neuropathy)

TÁMOP-4.1.2-08/1/A-2009-0011

Arrhythmias

• Atrial fibrillation – with heart failure

• AV-nodal re-entry tachycardia

• Multifocal ventricular premature beats

(polymorphic)

TÁMOP-4.1.2-08/1/A-2009-0011

Hypertension 1

• Age-related hypertension is mostly isolated systolic

hypertension (18-24 years 2.6%, above 75 70.3%,

50% undetected, above 80 the BP decreases)

• Due to the loss of elasticity in the aorta the pulse

wave returns too early, disturbing the systole and

increasing the systolic blood pressure too much

• The pulse-pressure increases, the diastolic pressure

decreases.

• This increased pulse-amplitude is one of the main

cardiovascular risk factors in the elderly

TÁMOP-4.1.2-08/1/A-2009-0011

Mean aortic pressure and

aortic pulse wave velocity vs. age

10

0

95

90

85

80

20 40 60 80 Age (years)

Me

an

aort

ic p

ressure

(m

mH

g)

▲, ∆

10

5

110

800

600

1,000

1,20

0

Urban Rural

Aort

ic p

uls

e w

ave v

elo

city (

cm

/sec)

●, ○

TÁMOP-4.1.2-08/1/A-2009-0011

Hypertension 2

• With age not only the amount of collagen increases but

also the rigidity of the collagen – progressive fibrosis

• The vascular diameter decreases relative to the vessel wall

+ endothelial damage decreases the vasodilatory activity

• RAAS activity decreases (decreased sympathetic tone,

decreased responsiveness).

• Plasma norepinephrine increases, but the β-receptor

responsiveness and sensitivity is down

• There is, on average, a 1% annual decrease in the cardiac

output.

• The proportional increase in total peripheral resistance

counteracts this decrease, but the adaptation capacity is

impaired.

TÁMOP-4.1.2-08/1/A-2009-0011

Hypertension 3

• Age-related hypertension is salt-sensitive – the

nephron number decreases from the original

800,000 to 400,000 by the age of 80. The salt

excretion is also decreased.

• This is explained partly through the decreased

glomerular function, partly by a decreased

production of natriuretic substances (PGE2,

bradykinin)

• The impaired activity of the Na-K ATP-ase pump

may contribute to hypertension – IC Na – Na+/Ca++

exchange – higher IC Ca – higher vascular tone

TÁMOP-4.1.2-08/1/A-2009-0011

Hypotension

• Decreased baroreceptor reflex + more rigid carotid

leads to a tendency for orthostatic hypotension and

an excessive HR increase upon standing up

• The BP of the elderly must be measured when sitting

and after standing up (BP fall > 20 mmHg)

• Tendency to develop hypovolemia (decreased thirst,

lower ECV, decreased responsiveness of regulatory

hormones) may promote hypotension and increase

mortality

TÁMOP-4.1.2-08/1/A-2009-0011

Hypertension and therapy

• Decreased filtration surface (decreased endogenous creatinine

clearance) Na retention and the need to apply thiazide diuretics.

• The renal and hepatic clearance of drugs decrease – drug doses

have to be adjusted

• The side effects are less tolerated by the elderly – therapeutic

compliance is decreased (ACE inhibitors – 30% cough, Ca-

channel blockers – 25% swelling of the legs, combined –

dizziness)

Therapy

ACE inhibitors (Angiotensin II type 1 receptor blockers) and

channel blockers (in the elderly appropriate therapy may increase

the well-being of the patient more effectively)

ACE inhibitors and β-blockers (-25% new DM) General outcome: -19 – -26% stroke, -25% coronary incident

manifestation of novel social challenges of the …...50% undetected, above 80 the bp decreases)...

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