O₂-rich 富氧血
O₂-poor 缺氧血
Coronary 冠状动脉
Animated dots show blood direction · 动画圆点显示血流方向
Rectangles = stocks (volumes / 存量). Arrows with triangle gates = flows (valves / 流量). Because the loop is closed, total volume is conserved: what leaves one stock must arrive in the next.
Coronary artery (O₂-rich) 冠状动脉 Coronary vein (O₂-poor) 冠状静脉 Capillary territory (muscle) 毛细血管供血区
The heart muscle gets zero oxygen from the blood passing through its chambers — it's perfused from outside, by branches of the aorta just above the aortic valve. At rest, O₂ extraction is already ~75% (the highest of any organ), so when demand rises the body must increase flow rather than extraction. Blood returns through the coronary veins into the great cardiac vein → coronary sinus → right atrium — closing the loop.
心肌并不从流经心腔的血液中摄取氧气，而是由主动脉瓣上方的分支（左主干、右冠状动脉）供血。静息状态下心肌的氧气摄取率已达 75%，是所有器官中最高的。需氧量增加时，心脏主要通过增加血流量来满足。静脉血经心大静脉汇入冠状窦，最终回到右心房。
Electrical → Mechanical: The SA node (窦房结) fires ~75×/min, sending a depolarisation wave through the atria (P wave), pausing at the AV node (房室结, ~120 ms delay for atrial filling), then racing down the bundle of His / Purkinje fibers to depolarise both ventricles simultaneously (QRS). Repolarisation follows (T wave). This electrical sequence triggers the mechanical contraction you see in the anatomy/Wiggers views above.
Pressure pulse: Each LV ejection launches a pressure wave at ~4–6 m/s along the aorta. You feel it as a pulse — at the carotid (~30 ms delay from aortic valve), radial (~120 ms), and femoral (~80 ms). The waveform morphology changes distally due to impedance mismatch and wave reflection (the "dicrotic notch" sharpens, systolic peak amplifies).
心脏的电传导系统控制心脏收缩节律。窦房结发出电信号 → 心房去极化（P 波）→ 房室结延迟 → His 束/浦肯野纤维 → 心室去极化（QRS）→ 复极化（T 波）。每次左心室射血产生压力波，以 4–6 m/s 的速度沿主动脉传播。颈动脉、桡动脉、股动脉处可感知脉搏，各有不同延迟。
Short answer: yes — it's the same frame that professional cardiovascular physiology uses. The loop is literally closed (blood volume is conserved moment-to-moment), so at steady state whatever the right ventricle pumps forward must return to it via the lungs and then leave the left ventricle into the body and come back through the veins. Stocks are the volumes sitting in each compartment; flows are the valves and vessels moving blood between them.
Use the closed-loop stock-and-flow model as your first mental model. Then add pulsatility (Wiggers) and nonlinearity on top. This is exactly the scaffolding used in physiology textbooks and CV simulation software.[4][5][6]
Next: Heart Rate Variability · 心率变异性 → — why a healthy heart is NOT a metronome. Interactive RR tachogram, Poincaré plot, PSD, and autonomic tone simulation.
All numbers are population means for a healthy adult at rest unless noted. Individual variation is large. This site is for education, not clinical use. 本站仅供教育使用，不作临床用途。