The duration of the problem of CHD causes weakness of instrumental diagnosis - ECG analysis is not enough. There was an idea to combine Bicycle test with hemodynamic parameters. The task was to present this relationship is convenient as the program for existing stress systems. So there was a “Stand of combining graphs of cardiac output and coronary circulation”, which allows to diagnose CHD and an old-school approach, with depression ST>2mm., and with depression ST=1mm., even ST=0.5 mm. But the main achievement of that “Stand” was that it determined what kind of myocardial ischemia occurs on the ECG: physiological ischemia of a healthy heart or ischemia in CHD.  Because, even when it became known that the depression ST>2 mm. occurs in healthy, the recommendation of the "to consider the interval ST depression>2mm, the symptom of CHD", has not been canceled. Although, perhaps, it was a stencil requirement of Metrology when measuring on a millimeter, at a price of division of 1 mm., reliable objects considered at least 2 mm. Medical sense of the situation was present in it only under 2 conditions:

1.The interval depression ST>2 mm. is not called healthy.

2.The interval depression ST>2mm. a reliable symptom of CHD.

        And in the absence of claim 1, can’t exist and claim 2. Myocardial ischemia in healthy individuals with ST>2mm. segment depression really exist. The clinic was not studied because it required loads of more than 300 watts, but studied by sport cardiologists. In the USSR it was done by Professor A. I. Zavyalov. who led to the victory of wrestlers of Belarus at the Olympic games-88 in Seoul. He has coached athletes loads that cause ECG depressed segment ST>2mm. On the site "Famous scientists of Russia", it is marked as the first, who showed that myocardial ischemia with depression of ST>2mm segment occurs in all. Clinicians pointed the differences of ischemia in CHD from it healthy:

 

Myocardial ischemia at ST>2 mm. in healthy and CHD patients

Indicator	Healthy people	People with CHD
EKG	ST>2 mm.	Depression ST>2 mm.
The development of the depression ST	More Often slow	More Often fast
Occurs at a load of	300-350watts & above	150 watts & below
The duration of the load	5-10 minutes or more	Minimum
Tolerability	Good	Satisfactory
The increased load	Allowed	Excluded
Feeling	Good	Satisfactory
Vegetative reactions	As a rule, no	Not rare
Blood pressure	Moderately elevated	Pathological reactions are not rare
Rhythm disturbances	As a rule, no	Not rare
Blockades	Doesn’t occur	Not rare
Cardiac arrest	Doesn’t occur	Quite real
The threat of life	Sertenly, Not	Quite real

 

 

         Since blood circulation – in this case, the Minute Volume of Blood (MVB) depends on blood circulation in the coronary arteries, they can be represented by graphs increasing to the maximum (WMax) load, as an exponent in the antiphase: where the arteries of the large circle are filled in the systole, coronary - in diastole. And, because their blood circulation is mutually proportional at each point in time, coronary ischemia is reflected in both graphs. According to the schedule of the MVB, it is possible to determine what is happening with the CHD myocardial ischemia. Where, as in the graph of coronary circulation, you can specify the exact time and load at the time of occurrence of myocardial ischemia. And, by changes in the MVB to distinguish ischemia in healthy from ischemia in CHD. And, to determine the depth of myocardial ischemia - the severity of CHD.  As you know, in healthy men, the MVB at rest is, on average, 5 liters. At maximum load, in people not trained, it increases 5 times, in athletes up to 6. In women, the MVB at rest, on average, is 4.5 liters and increases in 4-4.5 times, athletes - up to 5 times. That allows to present MVB of the healthy person a square with cells 5x5 and graphs of MVB and coronary circulation from rest to the maximum load: 

        The mutual proportionality of blood circulation allows you to determine the square line, which will always be located at the point of their conjugation in any state of coronary circulation – that is, at any size of the "Square of possibilities" of the myocardium. It crosses the square diagonally from the lower left corner to the opposite. The moment of myocardial ischemia is reflected on both charts, but on the MVB chart its increase or decrease is also estimated by color.

FOR EXAMPLE: The load that causes in a healthy person the myocardial ischemia with ST segment depression=1mm. always more Wmax "Square", so Wischemia out (axial loads) for the "Square" healthy for a distance of several reinforcing and the MVB healthy myocardium: (2)

        The difference in load (and a distance) between the Wishemia causing depression of the ST=1mm segment. and WMax, denote as "step norms" in healthy people. It’s always positive, as it increases the MVB, but in patients with CHD is always negative, as ischemia with coronary artery disease reduces the MVB. In healthy people, both blood circulation at the time of myocardial ischemia, pass – for some time - into a new state in which the MVB is slightly, but increases, increasing the "Square of possibilities" of a healthy myocardium. In the clinic, this condition of the myocardium is unknown, but it is well known by sports cardiologists, defining it as physiological, since it increases the physical capabilities of a person. In patients with CHD, ischemia develops at much lower loads than in healthy ones, indicating that the "Square of possibilities" of their myocardium is significantly less, therefore ischemia in it proceeds differently. In patients with CHD, the myocardium can’t provide normal blood circulation and its possibilities with a load that causes ischemia are reduced, and the "normal step" changes the sign. In CHD, myocardial ischemia the more reduces the possibility of myocardium, the more severe CHD(3);

              That is, the smaller the "Square of possibilities" in CHD, the more it reduces any caused by myocardial ischemia and the more dangerous it becomes for traditional Bicycle test. If have healthy, in average, Wmax. is from 300 to 350 watts, and the athletes Wmax reaches 450-500 watts, the CHD Wmax, reduced to 150 watts and below, and ST>2mm. attained by 130-120 watts, sometimes 90-80 watt. The maximum load is individual, as well as the "norm step", which is, on average, from 7 to 10% of Wmax.

     But with healthy myocardial ischemia, the "Square of possibilities" increases, while providing a stimulating effect of moderate ischemia on the myocardium, and with CHD, where there is already a decrease in the volume of the coronary bed, an additional load on the myocardium, causes an even greater decrease in coronary blood flow, which is reflected immediately on the MBV. Reducing the possibilities of myocardium in Coronary heart Disease reduces both the volume and speed of blood. That allows you to determine the development of CHD 3 different stages:

- reduced capacity of the myocardium in CHD without the clinic.

- clinic CHD manifests itself under significant strain.

- clinic CHD manifests itself under light load (4):

 

 

         In the first stage of CHD is latent. Bicycle test shows only the absence of a positive reaction to the "normal step". ST depression>2mm. not life-threatening – causes only a slight deterioration of health, several lowering the "Square".

In the second stage, the "normal step" becomes negative and the depression is ST>2mm. causes significant deterioration of health, expressed vegetative reaction and rhythm disorders, which already call and blockade.

In the third, with a further decrease in the "Square", depression ST>2mm. can lead to heart failure, if the depression appears when you load 90-80 watt. Therefore, the "Square" with an edge of 90-80watt, can be designated as the "square of death" for ST>2mm. He, apparently, and gives all the statistics of deaths on Bicycle test - as 10 000 times more dangerous than flying on an airplane.

 

 

          For the appearance on the ECG depressed ST segment=2mm is required and the load is twice as big - up to 20% of Wmax. In the first stage of CHD, such ischemia is achieved without risk to life, in the second stage of CHD can already provoke various rhythm disturbances, and in the 3rd stage of CHD, rhythm disturbances, blockade and cardiac arrest are almost guaranteed. Which makes ischemia with ST>2mm. deadly to this group. ST segment depression on the ECG indicates only the depth of myocardial ischemia, and on coronary artery disease itself, ST depression indicates indirectly – as occurring at lower loads. Therefore, CHD indicates a low load in ST depression, even in 0.5 mm.

The very form of the "square" does not matter: the diagnosis on it does not depend on the size of the MVB and not on the place and time of ischemia on the graf, as can be seen from the "Stands" with the MVB=17.3 l. of healthy woman:

     And a man with CHD with the MVB=16.6 l.:

 

                Discussion

1. More detailed description of the “Stand” is on the website iwanowvp.com

2."Square" is achieved by adjusting the dimension along the axis of loads – as a convenient form of perception, but also with a rectangle, all the properties of the stand are preserved.

3.The formula of the MBV. You can count “on Starr” and on the other, but all the more precise are the property of specific medical institutions.

4. "Liters of blood" are added in "liter" squares of 1/10 liter, that is, comparable to the Shock Volume of the Heart.

6.TPVR schedule is not indicated, but it, like some others, may be present, depending on the version – here described version 1.01. The “Stand” will be supplemented, and users will be notified about it.

             Summary

          This stand can be useful for the earliest and absolutely safe diagnosis of coronary heart disease on Bicycle test, without requiring changes in the design of stress systems already in operation.

          Intellectual property right.

        The software of each stress system is the Intellectual Property of the manufacturer. The doctor or institution can only contact the manufacturer of the stress system to install the described Stand. But, the printout should indicate that the used "Stand Ivanov" № version. After operation wishing to register on the website of the author with suggestions.

Abbreviations used:

ECG - Electrocardiogram

CHD – Coronary Heart Disease

MVB – Minute Volume of Blood

SV – Stroke Volume (Heart)

TPVR– Total Peripheral Vascular Resistance