CardiovascularCardiovascularSystem IISystem II
How do we measure blood pressure ?
Stroke volume (and hence, blood
pressure) are strongly influenced by the EDV
The regulation of blood pressure
The baroreceptor reflex
The regulation of blood pressure
Hypertension
Where to draw the limit of “normality” ?
12
48
16
32
64
128
256
Mort
alid
ad p
or
en
ferm
ed
ad c
oro
nari
a(x
1,0
00
paci
ente
s)
120 140 160 180
Usual BP (mmHg)
Age 80-89
Age 70-79
Age 60-69
Age 50-59
Age 40-49
Relationship between BP and CV riskMetaanalysis of more than 60 observational studies
Lancet 2002; 360: 1903–13
System/organ Impact of HTCNS Stroke, dementia
Myocardium Left ventricular hypertrophy
Hypertensive nephropathyKidney
Hypertensive retinopathyEye
Via heart failureAll body systems
Impact of chronic hypertension on body systems
Demographic
Cardiac
HTA
SexAge
Genetic
Angiotensinogen gene
Hyperaldosteronism
Cardiac output
Sodium retentio
nCaloric intake /
overweight
Renal
Gastrointestinal
Psychological
Stress
Central Nervous System
Sympathetic
hyperactivity
Vascular
Smooth muscle insulin sensitivity
Endothelial function
Why do some people develop hypertension while others don’t ?
Factors involved:
Atherosclerosis
Normal histology of the arterial wall
Infiltration of lipoproteins and
monocytes
Cell proliferation and differentiation in the
wall
Formation of “cap” and “shoulders”
Rupture and thrombosis
Atherosclerosis
World Deaths in millions
% of deaths
Coronary heart disease 7.20 12.2
Stroke and other cerebrovascular diseases
5.71 9.7
Lower respiratory infections 4.18 7.1
Chronic obstructive pulmonary disease
3.02 5.1
Diarrheal diseases 2.16 3.7
HIV/AIDS 2.04 3.5
Tuberculosis 1.46 2.5
Trachea, bronchus, lung cancers 1.32 2.3
Road traffic accidents 1.27 2.2
Prematurity and low birth weight 1.18 2.0
Top 10 world causes of death
