![]() ToHeart Remember my memories Anthology Drama CD vol.1 / ToHeart Remember my memories Anthology Drama CD vol.1 雨月山の鬼退治 / ToHeart Remember my memories Anthology Drama CD vol.1 Uzukiyama no Oni Taiji ToHeart2 Original Sound Track Limited Edition / ToHeart2 Original Sound Track Limited Edition / ToHeart2 Original Sound Track Limited Editionĭoko yori mo Hayai ToHeart2 Arrange CD / どこよりも早いToHeart2アレンジCD / Doko yori mo Hayai ToHeart2 Arrange CD ![]() TV Animation "ToHeart Remember my memories" Soundtrack & Image Song / TVアニメーション「ToHeart Remember my memories」サウンドトラック&イメージソング / TV Animation "ToHeart Remember my memories" Soundtrack & Image Song ToHeart2 Original Sound Track / ToHeart2 オリジナルサウンドトラック / ToHeart2 Original Sound Track ToHeart2 FIRST IMPRESSION CD / ToHeart2 先行すぺしゃるCD / ToHeart2 FIRST IMPRESSION CDĭaisuki da yo (Into Your Heart) / Naomi Tanizaki / 大好きだよ (Into Your Heart) / 谷咲ナオミ / Daisuki da yo (Into Your Heart) / Naomi Tanizaki SHOWA KINEN KOUEN / 昭和記念公園 / SHOWA KINEN KOUEN ![]() MAGICAL☆WAVES Premium CD Vol.5 / まじかる☆WAVES プレミアムCD Vol.5 / Magical WAVESīEST SOUND of GameMusicLibrary Vol.4 / BEST SOUND of GameMusicLibrary Vol.4 / BEST SOUND of GameMusicLibrary Vol.4 ToHeart Original Sound Track / To Heart オリジナル・サウンドトラック / ToHeart Original Sound Track Whoopee!pieces03 / Whoopee!pieces03 / Whoopee!pieces03 preload and afterload unchaged), raising contractility increases SV, and lowering contractility decreases SV.MY HEART YOUR HEART TO HEART / MY HEART YOUR HEART TO HEART / MY HEART YOUR HEART TO HEART If all else were kept constant, and contractility were increased (let's say by epinephrine release for example), then the ventricle would empty more of its contents during ejection stroke volume (SV) would increase. Contractility refers to the intrinsic strength of the ventricle, independent of loading condtions. All else being equal, raising afterload decreases SV, and lowering afterload increases SV. If afterload were increased, less of the blood in the ventricle would be ejected conversely, if afterload were decreased, more of the blood in the ventricle would be ejected. Under normal conditions, the heart does not eject all of its contents instead, it normally ejects approximately 2/3 of the blood that is in the chamber at end-diastole. ![]() Suffice it to say (for now) that the vessels can constrict or dilate, and thereby change the amount of total resistance to blood flow. Opposition to ejection is influenced by the state of the blood vessels (will be discussed in more detail in the blood flow in arteries section). Afterload refers to the forces that oppose ejection of blood out of the chamber. New answer: Length dependent activation of calcium channels. You might ask, why should end-diastolic sarcomere length affect strength of contraction? Old answer: greater availability for actin-myosin cross-bridging. The more they are stretched, the stronger is the contraction that occurs during systole, and the greater is the stroke volume. at the end of diastole, termed end-diastole), the more the sarcomeres are stretched. The more blood there is in the chamber just prior to systole (i.e. Preload refers to the stretch on the sarcomeres just prior to initiation of contraction (systole). SV stays at 100ml), raising the HR will raise the CO proportionally. That would mean that for each beat, the heart ejects 100 ml (Stroke Volume (SV)) of blood (to result in 5 liters being pumped each minute ). Let's say the heart rate at rest in a well-conditioned medical student is 50 beats per minute. So what are the mechanisms that allow for cardiac output to change? During exercise, cardiac output may increase upwards of 5-fold. At rest, cardiac output (CO) is typically 70 ml/kg/min (around 5 liters/min for a 70 kg person). This "right amount" may fluctate greatly, and swiftly, depending on such things as metabolic rate (the amount of oxygen being used by the tissues). The primary goal of the heart is to circulate the right amount of blood to the tissues such that adequate amounts of oxygen are delivered. ![]() What Determines How Much the Heart Pumps? Note that Pressure and Volume circles the loop in the counter-clockwise direction. When pressure is plotted as a function of volume, a Pressure-Volume Loop is generated as shown in the above right panel. It is important to understand what happens to LV pressure and volume throughout the cardiac cycle. ![]()
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