Stroke blood pressure control

Although blood pressure control follows Ohm s law and seems to be simple, it underlies a complex circuit of interrelated systems. Hence, numerous physiologic systems that have pleiotropic effects and interact in complex fashion have been found to modulate blood pressure. Because of their number and complexity it is beyond the scope of the current account to cover all mechanisms and feedback circuits involved in blood pressure control. Rather, an overview of the clinically most relevant ones is presented. These systems include the heart, the blood vessels, the extracellular volume, the kidneys, the nervous system, a variety of humoral factors, and molecular events at the cellular level. They are intertwined to maintain adequate tissue perfusion and nutrition. Normal blood pressure control can be related to cardiac output and the total peripheral resistance. The stroke volume and the heart rate determine cardiac output. Each cycle of cardiac contraction propels a bolus of about 70 ml blood into the systemic arterial system. As one example of the interaction of these multiple systems, the stroke volume is dependent in part on intravascular volume regulated by the kidneys as well as on myocardial contractility. The latter is, in turn, a complex function involving sympathetic and parasympathetic control of heart rate intrinsic activity of the cardiac conduction system complex membrane transport and cellular events requiring influx of calcium, which lead to myocardial fibre shortening and relaxation and affects the humoral substances (e.g., catecholamines) in stimulation heart rate and myocardial fibre tension. 

The clinical manifestations of PAD are associated with reduction in functional capacity and quality of life, but because of the systemic nature of the atherosclerotic process there is a strong association with coronary and carotid artery disease. Consequently, patients with PAD have an increased risk of cardiovascular and cerebrovascular ischemic events [myocardial infarction (Ml), ischemic stroke, and death] compared to the general population (4,5). In addition, these cardiovascular ischemic events are more frequent than ischemic limb events in any lower extremity PAD cohort, whether individuals present without symptoms or with atypical leg pain, classic claudication, or critical limb ischemia (6). Therefore, aggressive treatment of known risk factors for progression of atherosclerosis is warranted. In addition to tobacco cessation, encouragement of daily exercise and use of a low cholesterol, low salt diet, PAD patients should be offered therapies to reduce lipid levels, control blood pressure, control blood glucose in patients with diabetes mellitus, and offer other effective antiatherosclerotic strategies. A recent position paper... 

Here s a happy thought, something to inspire your commitment to good health in general and to blood pressure control in particular. Several—not just one or two—trials have demonstrated without doubt that reductions of systolic blood pressure by as little as one to three points will decrease your relative risk of stroke by as much as 20 to 30 percent. That s one heck of a return on your investment ... 

Schrier RW, Estacio RO, Esler A, Mehler P. Effects of aggressive blood pressure control in normotensive type 2 diabetic patients on albuminuria, retinopathy and strokes. Kidney Int 2002 61 1086-97. 

But if you come to them with a pharmacoeconomics study or a cost-benefit calculation and show that yours is a once-a-day dosage form and the others are three-times-a-day, and people are more compliant, there ll be better blood pressure control and fewer strokes, saving them tons of money, they ll say, Alright, 90 cents it is. ... 

Lowering blood pressure in patients who are hypertensive has been shown to reduce the relative risk of stroke, both ischemic and hemorrhagic, by 35% to 45%.23 Also, the more blood pressure is lowered, the greater the reduction in stroke risk.24 All patients should have their blood pressure monitored and controlled appropriately based on current guidelines for blood pressure management. However, no one agent has been clearly shown to be more beneficial than any other for preventing stroke. 

CHCs, even those with less than 35 meg estrogen, can cause small increases in blood pressure (6 to 8 mm Hg) in both normotensive and hypertensive women. In women with hypertension, OCs have been associated with an increased risk of MI and stroke. Use of CHCs is acceptable in women younger than 35 years with well-controlled and monitored hypertension. Hypertensive women with end-organ disease or who smoke should not use CHCs. Progestin-only pills and depot medroxyprogesterone acetate (DMPA) are choices for women with hypertension. 

A number of chronic conditions such as high blood pressure or diabetes bear certain similarities to snbstance use disorders. These illnesses prodnce a variety of physical symptoms that, if left untreated, can resnlt in significant medical complications and even death. Complications of uncontrolled diabetes inclnde blindness, kidney failure, neuropathies, and limb amputation. Similarly, inadeqnately controlled hypertension is a risk factor for stroke, heart attack, and other serions complications. Recognizing that these are diseases does not relieve the patient of responsibility indeed, the knowledge that one has snch an illness imposes significant responsibility. For example, knowing the likely ontcome of nncontrolled diabetes is hopefully an impetus for the diabetic to exercise, take medication, and... 

Coronary heart disease is one of the leading causes of death in the industrialized world (Packer, 1992 Remme and Swedberg, 2001). Hypertension is a risk factor for cardiovascular disease and is associated with an increased incidence of stroke and coronary heart disease. Other risk factors for cardiovascular disease include also high cholesterol, diabetes, and obesity. Although there have been many advances in treatment over the past several decades, less than a quarter of all hypertensive patients have their blood pressure adequately controlled with available therapies. 

Hypertension is a common disease marked by a sustained increase in blood pressure. If untreated, hypertension leads to serious problems such as stroke, renal failure, and problems in several other physiologic systems. Although the cause of hypertension is discernible in a small percentage of patients, the majority of hypertensive individuals are classified as having essential hypertension, which means that the cause of their elevated blood pressure is unknown. Fortunately, several types of drugs are currently available to adequately control blood pressure in essential hypertension. Drugs such as diuretics, sympatholytics... 

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