{"ops":[{"attributes":{"color":"#f85a54"},"insert":"房室延擱和全心舒張期"},{"insert":"\n\n"},{"attributes":{"color":"#00aeec"},"insert":"房室延擱"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"興奮經(jīng)過房室交界從心房傳到心室時，傳導(dǎo)速度減慢，耽擱了0.1秒"},{"insert":"\n\n"},{"attributes":{"color":"#18191c"},"insert":"為什么呢？"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"心肌細(xì)胞分為兩類"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"快反應(yīng)細(xì)胞：0期去極化是快鈉通道介導(dǎo)的鈉內(nèi)流，比如心室肌細(xì)胞"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"慢反應(yīng)細(xì)胞：0期去極化是慢鈣通道介導(dǎo)的鈣內(nèi)流，比如竇房結(jié)細(xì)胞"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"而影響心肌細(xì)胞傳導(dǎo)性最重要的因素是0期去極化速度與幅度"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"因此快反應(yīng)細(xì)胞傳導(dǎo)也快，慢反應(yīng)細(xì)胞傳導(dǎo)也慢"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"所以房室交界區(qū)之所以傳導(dǎo)速度慢是因為有慢反應(yīng)細(xì)胞—房室結(jié)細(xì)胞"},{"insert":"\n"},{"attributes":{"color":"#18191c"},"insert":"那么就可以用鈣拮抗劑維拉帕米來改變房室交界區(qū)的傳導(dǎo)"},{"insert":"\n\n"},{"attributes":{"class":"cut-off"},"insert":{"cut-off":{"type":"5","url":"https://b1.sanwen.net/b_article/02db465212d3c374a43c60fa2625cc1caeaab796.png"}}},{"insert":"\n1??有房室延擱的出現(xiàn)說明心房和心室的活動不同步\n那么有沒有房室同步的情況？\n有，三度房室傳導(dǎo)阻滯自帶房室分離的，間或可聞及大炮音\n\n2??生理上的房室延擱在心電圖上表現(xiàn)為PR間期0.12～0.20秒\n\n"},{"attributes":{"class":"normal-img"},"insert":{"native-image":{"alt":"read-normal-img","url":"https://b1.sanwen.net/b_article/9beb803fc1e71693b2a8849ef1c7581466050cc3.jpg","width":3024,"height":4032,"size":3352968,"status":"loaded"}}},{"insert":"???\n??有沒有PR間期<0.12秒的情況\n有，預(yù)激綜合征（WPW）\n是因為其在房室結(jié)之外長了一個Kent束，它并不存在房室延擱?（結(jié)外生枝）\n\n??生理學(xué)上的房室延擱是室上速快慢雙路徑中的快路徑\n所以一個房性早搏通過折返環(huán)中的慢路徑下傳，其后的P'R間期顯著延長\n\n3??房室延擱的這0.1秒就是心房收縮的0.1秒\n心動周期有0.8秒\n"},{"attributes":{"color":"#00aeec"},"insert":"全心舒張期"},{"insert":"0.4秒\n\n"},{"attributes":{"class":"normal-img"},"insert":{"native-image":{"alt":"read-normal-img","url":"https://b1.sanwen.net/b_article/6b9474da20818546a01e2388647ed248b141849b.jpg","width":3024,"height":4032,"size":3568497,"status":"loaded"}}},{"insert":"???心率增快，舒張期縮短\n而舒張期時心室充盈、冠脈血流量增加\n所以\n心率增快時會導(dǎo)致只見收縮不見泵血、只見心跳沒有脈搏，這就是房顫發(fā)作時的脈搏短促\n&一切快速心律失常都會發(fā)生心絞痛（冠脈沒有病變，也會發(fā)生心絞痛，亮瞎?。‐n\n"},{"attributes":{"class":"cut-off"},"insert":{"cut-off":{"type":"5","url":"https://b1.sanwen.net/b_article/02db465212d3c374a43c60fa2625cc1caeaab796.png"}}},{"insert":"\n"},{"attributes":{"color":"#f85a54"},"insert":"體循環(huán)平均充盈壓"},{"insert":"：循環(huán)血量與血管容量的匹配情況\n血容量大—血壓高，血容量小—血壓低\n所以治療高血壓最無恥的方法就是利尿\n\n復(fù)習(xí)一下：\n動脈血壓形成有四個因素：體循環(huán)平均充盈壓、心臟收縮、大動脈管壁彈性、外周阻力\n動脈血壓調(diào)節(jié)有五個因素：體循環(huán)平均充盈壓、心室搏出量、心率、大動脈管壁彈性、外周阻力\n心率：只調(diào)節(jié)不參與\n\n"},{"attributes":{"class":"cut-off"},"insert":{"cut-off":{"type":"5","url":"https://b1.sanwen.net/b_article/02db465212d3c374a43c60fa2625cc1caeaab796.png"}}},{"insert":"\n"},{"attributes":{"color":"#f85a54"},"insert":"直捷通路"},{"insert":"\n休克有三個時期：1??只出不進2??只進不出3??DIC\n只出不進是指血液進入微循環(huán)之后沒有進迂回通路，而是進入直捷通路回流了\n\n真毛細(xì)血管是迂回通路的\n通血毛細(xì)血管是直捷通路的\n\n微循環(huán)有三條通路：\n1??動靜脈短路（3個部分）：微動脈—動靜脈吻合支—微靜脈\n2??直捷通路（4個部分）???：微動脈—后微動脈—"},{"attributes":{"color":"#ffb027"},"insert":"通血毛細(xì)血管"},{"insert":"—微靜脈\n3??迂回通路（5個部分）???：微動脈—后微動脈—毛細(xì)血管前括約肌—"},{"attributes":{"color":"#ffb027"},"insert":"真毛細(xì)血管"},{"insert":"—微靜脈\n\n\n\n\n\n\n"}]}