[SCD-FORUM] 127C Hemodynamics. Dr. Chen

[SCD Symposium]

Dear Chairman, Douglas P. Zipes
Sudden cardiac death is mainly resulted from the disturbance of cardiac electrophysioloy which can cause severe deterioration of hemodynamics. There is about 400 thousand SCD cases in the USA annually, and one person is died from SCD in every minute. 20%-40% of them were in youth or middle age. About 75% of the dead had no aura of heart disease.

It was reported that SCD with organic heart disease occurred mainly in youth or middle age. 70% was healthy man under 40 years old. The underlying diseases are LQTS, Brugada syndrome, myocardial ischemia or infarction, and consequent ventricular fibrillation, that deteriorated hemodynamics, and finally heart stopped beating and brain death.
My question is about hemodynamics. Whether the theory or the study method in hemodynamics are reasonably in human heart? 
Almost all of the study or research about hemodynamics were established in an ideal model in physics, such as ideal fluid in ideal tube with constant pressure. However, the blood flow in arterial vessel is different from the ideal model, that is the velocity of the blood flow in the middle of the vessel is faster than that at the edge of the vessel wall.   
In Poiseuille's law:    Q =K×r4(P1－P2)/L =p r4(P1－P2)/ 8hL.
Q，blood flow, is the amount of blood passes a cross section area, also called volume speed.
R, resistance of blood flow, is determined by the friction in blood and between the blood and the vessel wall.
R= 8hL /p r4. According to this formula, if the radius of an artery is 1 cm and the arteriole is 20μm, the ratio of R in artery and in arteriole is 1:6.25×10(exp 10). This means that if the R in artery is 1g, there is a force of 6.25×10(exp 10)g to push the blood cells in arteriole. 
This is unbelievable and impossible. Because the human cardiovascular system are not ideal tube in physics. Arteries are different in diameter, have branches and elastic wall. Blood is a kind of inhomogenous, viscous fluid. Blood ejected from the heart intermittently, not in a constant pressure. The diameter of red blood cell is greater than capillary vessel, what push RBC change their shape and through capillary vessel.   It is axis flowing in artery, and how about small artery and arteriole? 
I am expecting a soon response from Douglas P. Zipes, a top rank scientist.

Hezhong Chen,
Associated professor ,
the cardiology department in the affiliated hospital of Leihe medical school,
Henan province, China
chinachenhezhong at 126.com