OverviewThe force of blood on artery walls is called blood pressure. Normal pressure is important for the proper flow of blood from the heart to the body's organs and tissues. Each heart beat forces blood to the rest of the body. Near the heart, pressure is higher, and away from it lower. Show
Blood pressure depends on many things, including how much blood the heart is pumping and the diameter of the arteries the blood is moving through. Generally, the more blood that's pumped and the narrower the artery the higher the pressure is. Blood pressure is measured both as the heart contracts, which is called systole, and as it relaxes, which is called diastole. Systolic blood pressure is measured when the heart ventricles contract. Diastolic blood pressure is measured when the heart ventricles relax. A systolic pressure of 115 millimeters of mercury is considered normal, as is a diastolic pressure of 70. Commonly, this pressure would be stated as 115 over 70.Stressful situations can temporarily cause blood pressure to rise. If a person has a consistent blood pressure reading of 140 over 90, he would be evaluated for high blood pressure. Left untreated, high blood pressure can damage important organs, such as the brain and kidneys, as well as lead to a stroke. Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. In order to grasp the concepts of measuring and interpreting hemodynamic values, it is important to understand how blood flowing through the heart is related to the cardiac cycle.
When the left ventricle (LV) contracts, it generates a systolic blood pressure of 100-140 millimeters of Hg (mm Hg).
The pressure of blood within the right atrium is the central venous pressure (CVP). The blood pressure of the vena cavae is similar to the CVP because there are no valves or flow obstructions between the vena cavae (VC) and the RA. The VC and heart's right side can be viewed as one chamber with a contractile portion at the distal end. The CVP averages between 2-6 millimeters of mercury (mm Hg). During right ventricular (RV) diastole, the pressure within the RV is between 0-5 mm Hg. Elasticity and compliance of the ventricular myocardium help generate a lower intraventricular pressure. Lower intraventricular pressure, aided by atrial systole, causes blood to flow across the open atrioventricular AV valve. Right ventricular systolic pressure is usually from 20-30 mm Hg. This exceed the right atrial pressure. The pressure gradient applies greater pressure to the ventricular side of the AV valve, which causes it to close. The pulmonary artery (PA) pressure, prior to systole, is normally 8-12 mm Hg. During RV systole the PA pressure will rise to equal the RV pressure, usually 20-30 mm Hg. The systolic PA pressure of 20-30 Hg is quickly dissepated by the compliance of the pulmonary vascular bed to a diastolic pressure of 8-12 Hg. Blood leaves the pulmonary vasculature at about 4-12 mm Hg, passively entering the pulmonary veins. The pulmonary veins empty directly into the left atrium. Elasticity and compliance of the ventricular myocardium help generate a slightly lower intraventricular filling pressure. Lower intraventricular pressure, aided by atrial systole, causes blood to flow across the open atrioventricular AV valve. LV systole generates 100-140 mm Hg. Aortic diastolic pressure is usually 60-90mm Hg. The pressure gradient of 100-140/60-90 mm Hg drives blood into the aorta and onward to the rest of the body. The cycle is complete.
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Which blood pressure reading is associated with the contraction of the left ventricle quizlet?Which blood pressure reading is associated with the contraction of the left ventricle? The systolic, or top, number in a blood pressure reading represents the pressure exerted on the arterial walls when the left ventricle contracts.
What is the blood pressure in the left ventricle?When the left ventricle (LV) contracts, it generates a systolic blood pressure of 100-140 millimeters of Hg (mm Hg). The aortic diastolic pressure is usually 60-90 mm Hg.
Which type of blood pressure occurs with the contraction of ventricles?Systolic blood pressure is measured when the heart ventricles contract. Diastolic blood pressure is measured when the heart ventricles relax. A systolic pressure of 115 millimeters of mercury is considered normal, as is a diastolic pressure of 70.
What is the pressure wave within an artery caused by contraction of the left ventricle?The systolic blood pressure is defined as the maximum pressure experienced in the aorta when the heart contracts and ejects blood into the aorta from the left ventricle (approximately 120 mmHg).
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