1) 有哪些方法, 为什么需要采用这些方法? 2) 有哪些参数, 这些参数的生理学意义是什么? 3) 功能的研究如何提示机制的改变?

Transcription

1 心脏泵功能的 测量方法 1

2 1) 有哪些方法, 为什么需要采用这些方法? 2) 有哪些参数, 这些参数的生理学意义是什么? 3) 功能的研究如何提示机制的改变? 2

3 心功能测量方法 In vivo 1. 超声法 2. 超声 + 导管法 In vitro 1. Langendorff mode 2. Working heart mode 3. Papillary muscle 4. Skinned fibers 5. Single cardiomyocyte 3

4 Cardiac output CO=HR SV Nerve Humoral factors SV=LVEDV-LVESV Preload Contractility Afterload Cardiac contractility is the intrinsic ability of heart muscle to generate force and to shorten, independently of changes in the preload or afterload with fixed heart rates. 4

5 1. 超声法 5

6 1. 左室舒张末期内径 (LVDd) 2. 左室收缩末期内径 (LVDs) 3. 左室短轴缩短率 (FS) 4. 左室舒张末期室间隔厚度 (LVSd) 5. 左室收缩末期室间隔厚度 (LVSs) 6. 左室舒张末期后壁厚度 (LVPWd) 7. 左室收缩末期后壁厚度 (LVPWs) 6

7 左室舒张末期容积 (LVEDV) 左室收缩末期容积 (LVESV) LVEDV = (5/6)π(LVDd/2) 2 Ld LVESV=(5/6)π(LVDs/2) 2 Ls LV mass=1.05({(5/6)π[(lvdd+ivsd+pwd)/ (Ld+WTad)}-[(5/6)π(LVDd/2) 2 7

8 2. 超声 + 导管法 一般指标 SP/DP/MAP LVESP/LVEDP HR 等容收缩相指标 dp/dt max t-dp/dt max dp/dt max /LVEDP dp/dt 40 or dp/dt 50 dp/dt 50 /LVEDVI 8

9 射血相指标 Peak V CF dv/dt dd/dt EF/ET 等容舒张相指标 -dp/dt max TR 1/2 or TR 75 9

10 Pressure-volume loop D, mitral valve opening A, end-diastole B, aortic valve opening and the beginning of ejection C, aortic valve closure 10

11 The end-systolic pressure-volume relationship (ESPVR) 11

12 Load-independent parameters of contractility (1)Ees : slope of the end-systolic pressure-volume relationship (2)Slope of dp/dtmax-edv relation (3)PRSW(preload-recruitable stroke work) Slope of cardiac stroke work (pressure volume)-edv relation 12

13 Millar 压力 - 容积导管 13

14 3. Langendorff mode - 主动脉逆行灌注法 14

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16 实验条件 灌流压 -60 mmhg 前负荷 - 水囊内压 7 mmhg Pacing at 6 Hz (360 beats/min) 16

17 心收缩功能参数 (1)Left ventricle end-systolic pressure (LVESP)-mmHg (2)LV end-diastolic pressure (LVEDP) (3)Left ventricle developed pressure (LVDP or LVDevP= LVESP-LVEDP) (4)Heart Rate (HR)-beats per minute (5)Rate Pressure Product (RPP)= LVDP x HR-mmHg/sec (6) dp/dt min and dp/dt max -mmhg/msec (7) Coronary Flow (ml/min) 17

18 (7)Myocardial oxygen consumption (MV O2 ) 氧电极测肺动脉中冠脉流出液的氧含量 MV O2 = (% O 2 perfusate - % O 2 pulmonary artery ) Coronary Flow Atmospheric Pressure / 760 x O 2 Solubility O 2 Density O 2 solubility=23.9 μl/ml O 2 density= μmol/μl at 37 (8)Cardiac efficiency (%)=RPP/MV O2 18

19 4.Working heart mode 19

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21 Parameters in mouse heart Body weight(g) Heart weight(mg) In vivo Heart rate(bpm) Blood pressure(mmhg) 135/106 In vitro Heart rate(bpm) Perfusion pressure(mmhg) Cardiac output (ml/min) Coronary flow(ml/min) Stroke volume (µl) 14.0 Cardiac work(mmhg. ml/min )

22 Millar 压力导管 22

23 LVESP TPT TR 75 23

24 主动脉压力 左心室内压 (Millar 导管 ) 左心室射血时间 每搏输出量每搏功 24

25 心收缩功能参数 (1)Cardiac output (2)Coronary flow (3)Pressure in aorta and left atrium (4)LVESP (5)LVEDP (6)Heart rate (7)Oxygen consumption (8)Heart work (Power)(J/min/g)=cardiac output (ml/min/g) aortic pressure(mmhg) (j/mmhg/ml) 25

26 (9)Contractility (dp/dt max ), relaxation (-dp/dt min ) (10)Time to peak pressure, half time of relaxation 处理条件 (1)Response to pharmacological stimulation (2)Response to electrical stimulation (3)Change in ion composition (4)responses to work load (Starling relationship) 数据分析 (1)5-15 heart beats (2)Time required to process data from one experiment is approximately min 26 (3)Using a double-blinded method

27 45 A * 40 CON T4 * * Preload (mmhg) 27 Cardiac output (ml/min)

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29 5. Skinned fibers 29

30 Skinned fibers 张力 -pca 曲线 30

31 6. Papillary muscle and single cardiomyocyte 31

32 E Per cent rod-shaped cells ** ** # 10 0 Fresh cells With calcium After 4 h After stimulating 分离心肌细胞 32

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35 Time to peak shortening (ms) ** ** ## ** ** ## CON 2wk T4 4wk T Frequency (Hz) ** ** ## Time from peak to 75% relaxation (ms) ** ** ## ** ** ## CON 2wk T4 4wk T Frequency (Hz) ** ** ## 35

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37 兴奋 - 收缩耦联与机制研究 37

38 收缩相相关环节或分子 细胞膜 Na-K ATP 酶活性 静息电位 动作电位平台期 LTCC 激活特性 Na-Ca exchanger 特性 RyR 开放特性 肌原纤维对 Ca 2+ 的敏感性 38

39 舒张相相关环节或分子 动作电位平台期 LTCC 失活特性 Na-Ca exchanger 特性 细胞膜 Ca 2+ -ATP 酶活性 SERCA 活性 肌原纤维对 Ca 2+ 的敏感性 39

40 谢谢! 40