Systolic pressure definition

The actual level of pressure that can be considered hypertensive is difficult to define it depends on a number of factors, including the patient s age, sex, race, and lifestyle. As a working definition, many cardiovascular treatment centers consider that a diastolic pressure of 90 mm Hg or higher or a systolic pressure of 140 mm Hg or higher represents hypertension. In this chapter, ref-... 

The term afterload has taken on several meanings in the literature and these include mean systolic stress, peak systolic stress, stress at aortic valve opening, mean aortic pressure and more recently, end systolic pressure and end systolic stress. The variety of definitions is simply due to the fact that afterload varies continuously throughout ejection. 

The development of practical methods for the assessment of myocardial contractility continues and while the ESP-ESV concept provides one approach for quantitating changes in the contractile state, it requires further modification in order that it may be employed for patient to patient comparison. The preliminary studies described here on the basis of the developed stress concept shows some promise, however, further studies are required to examine the relationships between peak systolic pressure and end diastolic volume in order to explore an alternative definition for developed stress. 

Pearlman ES, Weber KT, Janicki JS, Pietra G, Fishman AP (1982) Muscle fiber orientation and connective tissue content in the hypertrophied human heart. Lab Invest 46 158-164 Sagawa K (1981) The end-systolic pressure-volume relation of the ventricle Definitions, modifications and clinical use. Circulation 63 1223-1227... 

A-F This straight line represents the ESPVR. If a ventricle is taken and filled to volume a , it will generate pressure A at the end of systole. When filled to volume b it will generate pressure B and so on. Each ventricle will have a curve specific to its overall function but a standard example is shown below. Changes in contractility can alter the gradient of the line, a-f This curve represents the ED PVR. When the ventricle is filled to volume a it will, by definition, have an end-diastolic pressure a . When filled to volume b it will have a pressure b and so on. The line offers some information about diastolic function and is altered by changes in compliance, distensibility and relaxation of the ventricle. 

Thus, the physician must establish with certainty that hypertension is persistent and requires treatment and must exclude secondary causes of hypertension that might be treated by definitive surgical procedures. Persistence of hypertension, particularly in persons with mild elevation of blood pressure, should be established by finding an elevated blood pressure on at least three different office visits. Ambulatory blood pressure monitoring may be the best predictor of risk and therefore of need for therapy in mild hypertension. Isolated systolic hypertension and hypertension in the elderly also benefit from therapy. 

In experimental animals the effect of ephedrine administered intravenously is similar to that of epinephrine. The arterial pressure — systolic, diastolic, and mean pressure — rises and vagal slowing occurs. Compared with epinephrine, the pressor response to ephedrine occurs somewhat more slowly and lasts about ten times longer. Furthermore, it requires more ephedrine than epinephrine to obtain an equivalent pressor response. How much more depends on the species tested, type and degree of anesthesia, dose level, and individual variability of the test animal. It is, therefore, almost impossible to give a definite figure for the relative potency of ephedrine and epinephrine. It is commonly accepted that it requires about 250 times more ephedrine than epinephrine to achieve equipressor responses. 

Hypertension, whether labile or fixed, borderline or definite, casual or basal, systolic or diastolic, at any age regardless of gender is the most common and a powerful contributor to atherosclerotic coronary vascular disease. Morbidity and mortality increase progressively with the degree of elevation of either systolic or diastolic pressure and pulse pressure, and no discernible critical value exists (see Chap. 13). Numerous trials have documented the reduction in risk associated with blood pressure lowering however, most of these studies show that mortality and morbidity reduction is a result of fewer strokes and... 

Thus, echocardiography is recommended as a screening tool, but not as the definitive diagnostic tool in patients suspected of having pulmonary hypertension. For a particular patient, following the initial correlation of the echo estimate of PA pressure with direct catheterization measurement will allow subsequent patient specific correlations. Tricuspid annular plane systolic excursion (TAPSE) has been shown to correlate strongly with RV ejection fraction as assessed by radionuclide angiography (34). It has been used in both two- and three-dimensional evaluations, and as a means of serial follow-up studies of... 

A plethora of substances are normally employed to lower the blood pressure, though their efiect may be transient. A few of them are used for their hypotensive action. An arbitrary definition of normal adult blood pressme afforded by the World Health Organization (WHO)- is a systolic pressnre eqnal to or below 140 mm Hg together with a diastolic pressnre equal to or below 90 mm Hg. ... 

---