A Brief History of Tau with Links You Might Need!

A Brief History of Tau

1976, Tau was born in John Hopkins.
1992, the first non-invasive try, Harvard.
1992, the first formula, with five assumptions, Harvard.
1993, another non-invasive try with decent data, Mayo Clinic.
1995, a similar strategy applied to AI patients, Japan.
1995, I published a MR based formula with one assumption.
1997, the Harvard formula was validated in Cleveland.
2005, Langer presented a non-zero asymptote model.
2008, I improved my MR based formulas, without assumption.
2008, I did a similar deduction for AI based Tau.
2008, Chen developed program for my formulas, free download.
2008, my poster in ASE 19th Annual Scientific Sessions.
2009, my poster in CSE forum.
2009, DF guideline (ASE) recommended Harvard formula.
2009, I gave my opinion about the guideline recommendation.
2009, "Response to Bai" from guideline writing group. It motivated me to create this Blog.
2010, Dr Wang and me pushed Tau to all cardiac functions.
2011-11-29, I gave a talk in National Capital Echo Round (Ottawa)
2016-03-29, I gave a talk at the Heart Institute, the North Hospital (Shenyang, China)
2016-04-01, I gave a talk at the Cardiac Function Dept., the 1st Clinical College, Chinese University of Medicine. (Shenyang, China)
2016, Symmetry inspired by the approach of Tau.
2017, Calculation of LAP (based on my formulas) got a Chinese Natural Science Founding.

Wednesday, October 25, 2017

Why can Mindray make the first Tau-measurable ultrasound machine?

In 1976, the left ventricular diastolic time constant, Tau was found at John Hopkins. According to the definition, it can be accurately measured in a catheter lab, and soon, Tau was well accepted as the best index to describe left ventricular diastolic function. For the possibility of measuring it in the Echo lab and make it more accessible to clinicians, intensive investigation was done in 1990s at Harvard, Mayo Clinic, Cleveland, Osaka University, etc.

However, Mindray, the largest Chinese medical equipment company has just launched its Tau-measurable high-end ultrasound machine DC80. How? Why?

Sunday, October 9, 2011

A Small Step in Math, A True Stride in Cardiology

With the progress of Doppler and modern computer technology, I believe that only a few RBCs’ leaking will be needed to give us a much understandable and clear regurgitation curve. Theoretically, merely a short part of the curve is enough to calculate the Tau. As long as we are allowed to choose 3 points from within the definition field, we can use the updated formulas to proceed. Let’s assume the 3 points are a (va, ta), b (vb, tb) and c (vc, tc) from left to right. The updated formulas are:

Sunday, December 5, 2010

Sunday, October 31, 2010

-dp/dt max is equivalent to Tau

Recently, an editorial (1) from Circulation Heart Failure claimed “Tau derived from the monoexponential model is less dependent on loading conditions than peak -dp/dt and has been used as a reliable index for LV relaxation in many clinical and experimental studies.”

I think –dp/dt max and Tau are the SAME in terms of clinical significance.

Saturday, October 16, 2010

CAAM, a clinical call for help from the echo engineers.

Accurate measurement of time intervals is critically important for successful Tau calculation. Garbage in, garbage out. But don't hesitate to move forward. We just need something like computer aided accurate measurement, CAAM. I figured out this word. :)

Saturday, October 2, 2010

My response to "response to Bai"


"Response to Bai" reiterated why those 5 assumptions are acceptable. However, I developed my formulas without assumption.