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In cardiovascular physiology, stroke volume (SV) is the volume of blood pumped from the left ventricle of the heart per beat. Stroke volume is calculated using measurements of ventricle volumes from an echocardiogram and subtracting the volume of the blood in the ventricle at the end of a beat (called end-systolic volume) from the volume of blood just prior to the beat (called end-diastolic volume). The term ''stroke volume'' can apply to each of the two ventricles of the heart, although it usually refers to the left ventricle. The stroke volumes for each ventricle are generally equal, both being approximately 70 mL in a healthy 70-kg man. Stroke volume is an important determinant of cardiac output, which is the product of stroke volume and heart rate, and is also used to calculate ejection fraction, which is stroke volume divided by end-diastolic volume. Because stroke volume decreases in certain conditions and disease states, stroke volume itself correlates with cardiac function. ==Calculation== Its value is obtained by subtracting end-systolic volume (ESV) from end-diastolic volume (EDV) for a given ventricle. : In a healthy 70-kg man, EDV is approximately 120 mL and ESV is approximately 50 mL, giving a difference of 70 mL for the stroke volume. "Stroke work" refers to the work, or pressure of the blood ("P") multiplied by the stroke volume. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Stroke volume」の詳細全文を読む スポンサード リンク
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