Systolic pressure importance

Systolic pressure, or maximum blood pressure, occurs during left ventricular systole. Diastolic pressure, or minimum blood pressure, occurs during ventricular diastole. The difference between systolic and diastolic pressure is the pulse pressure. While diastolic blood pressure has been historically been used as the most relevant clinical blood pressure phenotype, it has now been clearly established that systolic blood pressure is the more important clinical predictor for cardiovascular morbidity and mortality. More recently, additional attention is focussed on the importance of pulse pressure, i.e. the blood pressure amplitude, as a predictive factor for cardiovascular disease. 

In the United States, African-Americans are twice as likely as Caucasians to experience hypertension. After age 65 years, African-American women have the highest incidence of hypertension. Essential hypertension cannot be cured but can be controlled. Many individuals experience hypertension as they grow older, but hypertension is not a part of healthy aging. For many older individuals, the systolic pressure gives the most accurate diagnosis of hypertension. Display 42-2 discusses the importance of the systolic pressure ... 

Considerable controversy has snrronnded the issue of the importance of outflow tract obstruction in conjunction with HCM. The presence of a gradient (the systolic pressure difference between the body and the outflow tract of the left ventricle) is indicative of a dynamic obstruction of the LV outflow tract. Outflow tract gradients occur in about 25% of patients with HCM. ° The obstruction that occurs usually shows spontaneous variabihty and may be reduced by interventions that decrease myocardial contractility. The gradient can be augmented by factors that increase contractility (Table 18-4). LV outflow tract obstruction at rest has been found to be a predictor of progression to severe HP symptoms, stroke, and death. ... 

An ongoing assessment is important for tlie patient taking an antianxiety dmg. The nurse checks tlie patient s blood pressure before drug administration. If systolic pressure drops 20 mm Hg, Hie nurse witliholds die drug and notifies die primary liealdi care provider. The nurse periodically monitors the patient s mental status and anxiety level during therapy. The nurse assesses for improvement or worsening of behavioral and physical symptoms identified in die preadministration assessment. 

Finally, drug treatment in the elderly is of great importance and warrants special attention with regard to safety and tolerability, since systolic blood pressure is recognized as an important target for treatment, particularly in older persons. The benefits of antihypertensive treatment in the elderly and in patients with isolated systolic hypertension are greater than in younger persons. 

The selection of blood pressure cuff size based on a patient s arm circumference is crucial for the accurate measurement of blood pressure. Systolic and diastolic blood pressure tend to increase when the cuff size is too small relative to the patient s arm circumference. This circumstance is important due to the increasing prevalence of obesity in developed nations. Currently, the guidelines of the American College of Cardiology/American Heart Association (ACC/AHA) Blood Pressure Measurement in Humans recommends cuff sizes for small, standard, and large adults with an optimal 2 1 ratio of cuff length/width based on arm circumference.18... 

You can see that the missing systolic blood pressure value for visit 2 is now properly assigned for subject 101. If order is important when transposing row data to columns, then the use of an ID statement in PROC TRANSPOSE is imperative. Otherwise, your data will silently shift to the left in the transposed file. 

Pharmacology The principal pharmacological action of nitrates is relaxation of the vascular smooth muscle and consequent dilation of peripheral arteries and especially the veins. Dilation of the veins promotes peripheral pooling of blood and decreases venous return to the heart, thereby reducing left ventricular end-diastolic pressure and pulmonary capillary wedge pressure (preload). Arteriolar relaxation reduces systemic vascular resistance, systolic arterial pressure, and mean arterial pressure (afterload). Dilation of the coronary arteries also occurs. The relative importance of preload reduction, afterload reduction, and coronary dilation remains undefined. 

Arteriolar and venous tone (smooth muscle tension) both play a role in determining myocardial wall stress (Table 12-1). Arteriolar tone directly controls peripheral vascular resistance and thus arterial blood pressure. In systole, intraventricular pressure must exceed aortic pressure to eject blood arterial blood pressure thus determines the systolic wall stress in an important way. Venous tone determines the capacity of the venous circulation and controls the amount of blood sequestered in the venous system versus the amount returned to the heart. Venous tone thereby determines the diastolic wall stress. 

Diuretics are the mainstay of heart failure management and are discussed in detail in Chapter 15. They have no direct effect on cardiac contractility their major mechanism of action in heart failure is to reduce venous pressure and ventricular preload. This results in reduction of salt and water retention and edema and its symptoms. The reduction of cardiac size, which leads to improved pump efficiency, is of major importance in systolic failure. Spironolactone and eplerenone, the aldosterone antagonist diuretics (see Chapter 15), have the additional benefit of decreasing morbidity and mortality in patients with severe heart failure who are also receiving ACE inhibitors and other standard therapy. One possible mechanism for this benefit lies in accumulating evidence that aldosterone may also cause myocardial and vascular fibrosis and baroreceptor dysfunction in addition to its renal effects. 

These agents cause small increases in cardiac output associated with higher systolic and diastolic blood pressure and heart rate. The pressure returns to normal when treatment is terminated. Although the magnitude of the pressure change is small in most patients, it is marked in a few. It is important that blood pressure be followed in each patient. An increase in blood pressure has been reported to occur in a few postmenopausal women treated with estrogens alone. 

EP1 receptor knock-out mice show reduced pain sensitivity, suggesting an important role for this receptor subtype in pain perception (Stock et al., 2001). Furthermore these mice show a significant reduction in systolic blood pressure and an increased renin angiotensin activity, suggesting a role also in cardiovascular homeostasis. 

In the Women s Health Initiative Calcium/Vitamin D Trial, a large number of postmenopausal women (n = 36,282) were supplemented with 1000 mg of elemental calcium and 400 IU vitamin D daily or placebo for 7 years. The study found no significant decrease in either systolic or diastolic blood pressure (Margolis et al., 2008). The results from the Women s Health Initiative Trial further emphasized the importance of dairy per se rather than calcium for the effect on blood pressure. 

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