Post on 22-Dec-2015
transcript
Introduction Epidemiology Classification Essential Hypertension Secondary Hypertension Effects of Hypertension Patient Evaluation
Outline
Bp one of the most important public health problems esp.in developed nations.
is: common, asymptomatic, readily detectable, usually easily treatable & often leads to lethal
complications if left untreated
Introduction
Depend on racial composition of population,sex,age & crieria used to define the condition.
Worldwide ~ 1billion individuals with HTN >50million americans have HTN European journal of epid.,june 2005-- prevalence
of HTN and the age-related behaviour of SBP and DBP in a wide sample of male and female Ethiopian Oromos living in rural o.4%
pre-industrial urbanized settings3.15%(8X) BW &life style
Prevalence
Morbidity- WHO report :-62% cerebrovascular disease
& 49% of IHD with little variation by sex is due to HTN
Mortality-worldwide ~ 7.1 million deaths
per year.
No specific cause can be identified
Interplay of various derangement in factors affecting BP
Abnormality may differ in both type & degree in different patients(Known risk frs.-age, race,sex,level of BP, DM, alcoholism , obesity,smoking)
Development of disease is slow & gradual
By time of BPno initiating factor may be apparent
Mechanisms of 1o(essential)HTN
Individuals in whom specific structural organ or gene defect is responsible for HTN
Responsible for small minority of total hypertensives
Patients should not be ignored for:correction of cause may cure HTN & may provide insight to etiology of HTN
Nearly all related to alteration in hormone secretion &/or renal function
Secondary Hypertension
May not manifest but only BP;even if target organ damage is happening(“Silent killer”)
When symptomatic could be non specific or complications (accelerated,malignant,urgency)
Patients with HTN die prematurely
Most common causes of death are:heart disease,stroke and renal failure.
Effects of hypertension
Early compensation of excessive workload is concentric LV hypertrophy
Ultimately: chamber function deteriorates , cavity dilates(LV,LA,Ao root),+/-angina, arrhythmia
sx/sn of CHF(systolic/diastolic/ischemic) ECG ,Echo changes Most deaths due to MI or CHF
Effects on heart
Neurologic effects
Retinal changes(only tissue in w/c arteries & arterioles can be examined directly)
CNS sxs(head ache,vert.,tinn.,sync)
most serious-vascular occlusion,hemorrhage,encephalopathy
Autoregulation of Cerebral Arterial Blood Flow
initial or in mean arterial pressure maintenance of blood flow due to appropriate changes in arteriolar resistance.
More marked changes in pressure loss of autoregulation blood flow (with hypotension) or (with marked hypertension) due to arteriolar thickening
Effects on Kidney LM reveals
fibrinoid necrosis in the preglomerular afferent arteriole
GFR & tubular dysfun.
The normal muscle layer of the media has been replaced by the fibrinoid material.
Hx,P/E,Ix directed at: 1)Uncovering correctable 20 forms 2)Establishing a pretreatment baseline 3)Assessing factors that may influence
the type of therapy or be changed adversely by therapy
4)Determining if target organ damage is present
5)Determining presence of other risk factors for development of arteriosclerotic CV disease
Patient Evaluation
Range from O factor-low risk to 3 or more factors (high risk)
Factors are – smoking, -obesity, -male gender, -high risk equivalent – to having
diabetes , target organ damage(clinical cardiovascular or renal disease) or both high risk if present regardless of other risk factors.
Risk stratification