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Hypertension. By:Dawit Ayele. Outline. Introduction Epidemiology Classification Essential Hypertension Secondary Hypertension Effects of Hypertension Patient Evaluation. Introduction. Bp one of the most important public health problems esp.in developed nations. is: common,
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Hypertension By:Dawit Ayele
Outline • Introduction • Epidemiology • Classification • Essential Hypertension • Secondary Hypertension • Effects of Hypertension • Patient Evaluation
Introduction • 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
Prevalence 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
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.
Mechanisms of 1o(essential)HTN • 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,levelof BP, DM, alcoholism , obesity,smoking) • Development of disease is slow & gradual • By time of BPno initiating factor may be apparent
Secondary Hypertension • 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
Effects of 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:heartdisease,strokeand renal failure.
Effects on heart • 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
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.
Patient Evaluation • 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
Risk stratification • 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.