1、SYSTEMIC HYPERTENSION,RANDA M. AL-HARIZYProf. of Internal Medicine,SYSTEMIC HYPERTENSION,Definitions of hypertension Elevated arterial blood pressure is a major cause of premature vascular disease leading to cerebrovascular events, ischaemic heart disease and peripheral vascular disease.,Hypertensio
2、n - Introduction,Silent Killer painless complications It is the leading risk factor MI, HF, CRF Stroke Responsible for the majority of office visits, Number one reason for drug prescription. 25% of population Complications bring to diagnosis but late,Regulation of BP:,BP = Cardiac Output x Periphera
3、l Resistance Endocrine Factors Renin, Angiotensin, ANP, ADH, Aldosterone. Neural Factors Sympathetic & Parasympathetic Blood Volume Sodium, Mineralocorticoids, ANP Cardiac Factors Heart rate & Contractility.,Control of Blood Pressure:,Blood Volume Na+, Aldosterone,Vasoconstrictors Angiotensin II Cat
4、echolamines,Vasodilators Pg & Kinins,Local Factors pH, Hypoxia,Neural Factors Adrenergic Cons Adrenergic - Dil,Cardiac Factors Rate & Contract,Humoral Factors,Etiology,1- Essential: In more than 95% of cases, an underlying cause cannot be found. Proposed mechanisms include: Excess renal sodium reten
5、tion Over activity of sympathetic nervous system Renin angiotensin excess Hyperinsulinemia Alterations in vascular endothelium,Factors contributing to the development of Essential hypertension,Genetic Factors: hypertension is more common in some families and in some ethnic groups like African Americ
6、ans Environmental factors include obesity, alcohol, lack of exercise and excess salt intake,2- Secondary hypertension,Renal: These account for over 80% of the cases of secondary hypertension. The common causes are diabetic nephropathy, chronic glomerulonephritis, adult polycystic disease, chronic tu
7、bulointerstitial nephritis, and renovascular disease. Endocrinal: These include Conns syndrome, adrenal hyperplasia, acromegaly, Phaeochromocytoma, Cushings syndrome. Drugs and toxins Pregnancy-induced hypertension Vascular: coarctation of aorta, vasculitis,Complications,Cerebrovascular disease and
8、coronary artery disease are the most common causes of death, although hypertensive patients are also prone to renal failure and peripheral vascular disease.,HYPERTENSION,Classification of blood pressure levels: (according to the British Hypertension Society)Category Systolic blood pressure Diastolic
9、 blood pressure Optimal 120 80 Normal 130 85 High normal 130-139 85-89 Hypertension Grade I (mild) 140-159 90-99 Grade 2 (moderate) 160-179 100-109 Grade 3 (severe) 180 110Isolated systolic hypertension Grade 1 140-149 90 Grade 2 160 90,Malignant Hypertension,Malignant or accelerated hypertension oc
10、curs when blood pressure rises rapidly and is considered with severe hypertension (diastolic blood pressure 120 mmHg). Unless treated, it may lead to death from progressive renal failure, heart failure, aortic dissection or stroke. The changes in the renal circulation result in rapidly progressive r
11、enal failure, proteinuria and haematuria. There is also a high risk of cerebral oedema and haemorrhage with resultant encephalopathy, and in the retina there may be flame-shaped haemorrhages, cotton wool spots, hard exudates and papilloedema,HISTORY,The patient with mild hypertension is usually asym
12、ptomatic. Attacks of sweating, headaches and palpitations may point towards the diagnosis of phaeochromocytoma. Higher levels of blood pressure may be associated with headaches, epistaxis or nocturia. Breathlessness may be present owing to left ventricular hypertrophy or cardiac failure. Malignant h
13、ypertension may present with severe headaches, visual disturbances, fits, transient loss of consciousness or symptoms of heart failure.,EXAMINATION,Elevated blood pressure is usually the only abnormal sign.Signs of an underlying cause should be sought, such as renal artery bruits in renovascular hyp
14、ertension, or radiofemoral delay in coarctation of the aorta. The cardiac examination may also reveal features of left ventricular hypertrophy and a loud aortic second sound. If cardiac failure develops, there may be a sinus tachycardia and a third heart sound.,Hypertensive Retinopathy:,Grade I Thic
15、kening of arterioles. Grade II Focal Arteriolar spasms. Vein constriction. Grade III Hemorrhages (Flame shape), dot-blot and Cotton wool and hard waxy exudates. Grade IV - Papilloedema,INVESTIGATIONS,Routine investigation of the hypertensive patient should include: ECG Urine stix test for protein an
16、d blood Fasting blood for lipids (total and high-density lipoprotein cholesterol) and glucose Serum urea, creatinine and electrolytes.,Investigation of selected cases,Chest X-ray Ambulatory BP recording Echocardiogram Renal ultrasound Renal angiography Urinary catecholamines Urinary cortisol and dex
17、amethasone suppression test Plasma renin activity and aldosterone,Non-pharmcological treatment,Weight reduction - BMI should be 25 kg/m2 Low-fat and saturated fat diet Low-sodium diet - 6 g sodium chloride per day Limited alcohol consumption - 21 units/week for men and 14 units/week for women Dynami
18、c exercise - at least 30 minutes brisk walk per day Increased fruit and vegetable consumption Reduce cardiovascular risk by stopping smoking and increasing oily fish consumption.,Pharmcological treatment should be based on the following,The initiation of antihypertensive therapy in subjects with sus
19、tained systolic blood pressure (BP) 160 mmHg, or sustained diastolic BP 100 mmHg. In patients with diabetes mellitus, the initiation of antihypertensive drug therapy if systolic BP is sustained 140 mmHg, or diastolic BP is sustained 90 mmHg. In non-diabetic hypertensive subjects, treatment goals: BP
20、 140/85 mmHg. In some hypertensive subjects these levels may be difficult to achieve. Most hypertensive patients will require a combination of antihypertensive drugs to achieve the recommended targets. In most hypertensive patients, therapy with statins and aspirin to reduce the overall cardiovascul
21、ar risk burden. Glycaemic control should be optimized in diabetics (HbA1c 7%).,Pharmacological Treatment,Several classes of drugs are available to treat hypertension. The usual are: ACE inhibitors or Angiotensin receptor antagonists Beta-blockers Calcium-channel blockers Diuretics Other drugs as -bl
22、ocker, direct vasodilator, or centrally acting drugs,Choice of antihypertensive therapyThe choice of antihypertensive therapy is usually dictated by cost, convenience, the response to treatment and freedom of side effects Comorbid conditions may have an important infleunce on initial drug selection
23、e.g. -blocker in angina Thiazide diuretics and calcium antagonists in elderly people ACE in heart failure, post MI, type 1 diabetic nephropathy ARBs in type 2 diabetic nephropathy, intolerance to ACE -blocker in benign prostatic hypertrophy,Management of severe or malignant hypertension Patients wit
24、h severe hypertension (diastolic pressure 140 mmHg), malignant hypertension (grades 3 or 4 retinopathy), hypertensive encephalopathy or with severe hypertensive complications, such as cardiac failure, should be admitted to hospital for immediate initiation of treatment. In most cases, the aim is to
25、reduce the diastolic blood pressure to 100-110 mmHg over 24-48 hours. This is usually achieved with oral medication, e.g. atenolol or amlodipine. Blood pressure can then be normalized over the next 2-3 days. When rapid control of blood pressure is required (eg. in aortic dissection), the agent of ch
26、oice is IV sodium nitroprusside. Alternatively, infusion of labetalol can be used. The infusion dosage must be titrated against blood pressure response.,Management of hypertension in pregnancy,Mild hypertension can be treated with methyldopa, which has been established as being safe in pregnancy, or
27、 labetalol. Pre-eclamptic hypertension can be treated with the same agents, or nifedipine, although the only method for reversal of overt pre-eclampsia is delivery. More severe hypertension or eclampsia requires treatment with intravenous hydralazine and may even require termination of the pregnancy
28、.,PROGNOSIS,The prognosis from hypertension depends on a number of features: Level of blood pressure Presence of target-organ changes (retinal, renal, cardiac or vascular) Coexisting risk factors for cardiovascular disease, such as hyperlipidaemia, diabetes, smoking, obesity, male sex Age at present
29、ation. Several studies have confirmed that the treatment of hypertension, even mild hypertension, will reduce the risk not only of stroke but of coronary artery disease as well.,Summary,Hypertension is the commonest cause of major morbidity, but less than a quarter of patients are adequately treated
30、. A reduction in cardiovascular disease mortality and morbidity can be achieved through improved treatment and control of hypertension. A greater choice of drugs are available for hypertension than for other chronic diseases. Rational choice of single and combination drugs facilitated by understanding their effects on the renin system, but systematic trial and error may still be necessary.,THANK YOU,
