WO1997031568A1

WO1997031568A1 - Method and apparatus for measuring cardiocirculatory functionality

Info

Publication number: WO1997031568A1
Application number: PCT/US1997/002609
Authority: WO
Inventors: Sabine V. Kunig
Original assignee: Kunig Sabine V
Priority date: 1996-02-27
Filing date: 1997-02-21
Publication date: 1997-09-04
Also published as: US5810011A

Abstract

A diagnostic and monitoring device (4) is disclosed to determine functionality of the cardio-circulatory system from a performance diagram. The performance diagram diagnoses myocardial impairment, dysfunctions, critical illness, and physical fitness of a subject from the location of a subject's data point with respect to zones of physiological criticality.

Description

METHOD AND APPARATUS FOR MEASURING CARDIOCIRCULATORY FUNCTIONALITY

BACKGROUND OF THE INVENTION

1. Field of the Invention: The present invention relates to cardiac functionality and, more specifically, to a method and apparatus for diagnosis

5. for determining cardiocirculatory f nctionality from performance diagrams.

2. Description of Prior Art: Present hemodynamic evaluation of a subject includes the measurement of a plurality of parameters such as 0 cardiac pressure, heart rate, cardiac output, electrocardiographic signals, and pulmonary and vascular resistance and a determination whether these parameters fall into an empirically established normal range. Each parameter is representative of only a 5 specific aspect of the entire cardiocirculatory system. Therefore, hemodynamic measurements fail to provide an over-all assessment of the system due to the absence of the synergy of the measured data. Ambiguous diagnosis may result from these types of hemodynamic 0 measurements.

Disclosed in U.S. Patent 5,370,122 is a method and an apparatus to establish the synergy of measured parameters in the form of cardiac pressure- size curves. Deviations of instant pressure-size curves from basal pressure-size curves produce changes in the numerical values of cardiac efficiency, indicative of myocardial impairment, and in the numerical values of cardiac work, indicative of dysfunctions. Not disclosed in the '122 patent, however, is the synergy of the measured parameters to provide functionality of the cardiocirculatory system 5. and allowing diagnosis of myocardial impairment, dysfunctions, critical illness, and physical fitness in a single reference frame of a performance diagram, PD.

It is an object of the invention to provide a PD for diagnosing the functionality of the 0 cardiocirculatory system and, more specifically, for diagnosing myocardial impairment, dysfunction, critical illness, and physical fitness.

It is another object of the present invention to provide a PD for diagnosing myocardial impairment 5 and facilitating the design of therapies affecting myocardial impairment and for monitoring the efficacy of these therapies.

It is furthermore an object of the present invention to provide a PD for diagnosing dysfunctions 0 and critical illness to allow the design of therapies affecting dysfunctions and the critical illness and/or the monitoring of these therapies.

It is still another object of the invention to provide a PD for diagnosing physical fitness to 5 allow the design of rehabilitation and conditioning exercise programs and/or the monitoring of these programs. SUMMARY OF THE PRESENT INVENTION According to the present invention, there is provided a cardiac diagnostic device and method for diagnosis of the functionality of the cardiocirculatory 5_. system in form of PDs from which myocardial impairment, dysfunctions, critical illness, and cardiocirculatory fitness may be diagnosed. The device establishes cardiac functionality of an individual over a time interval. The device includes the combination of a 0 sensor for measuring a physiological parameter A of the individual at an initial time t₁ and at a subsequent time t₂, a computer for computing the value for A_eff corresponding to cardiac functionality, according to the equation: 5 A_eff = (Aft,,) - A ( t₂χχ * Aft.)

A(t,) where: (Aft,,) - A(t₂) ) = CF and

Aft.) where CF is the efficiency with which Aft.,) is 0 converted into A_eff, and a reference frame receiving a data reference value corresponding to the computed value for A_eff in relation to boundary values defining physiological criticality of cardiac fitness for assessment of cardiac functionality of such an 5 individual. In the preferred form of the invention the reference frame is used with signals corresponding to body surface area, and criticality, and means for comparing the measured and derived signals with the signals of criticality for determining myocardial impairment, dysfunction, critical illness, and physical fitness, and means for producing audible or visual signals to alert upon the attainment of specific levels 5_. of myocardial impairment, dysfunctions, critical illness, and exercise intensity.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood when the following detailed description is 0 read in conjunction with the accompanying drawings in which:

FIG. 1 illustrates the time sequence of electromechanical signals during one heart beat;

FIG. 2 illustrates a PD used to determine 5 functionality of the cardiocirculatory system and to diagnose myocardial impairment, dysfunctions, critical illness, and physical fitness;

FIG. 3 shows a block diagram of the apparatus to practice the instant invention; 0 FIG. 4 illustrates the utility of the present invention to diagnose myocardial impairment, dysfunction, and critical illness of a patient afflicted with the acute respiratory disease syndrome from a PD; 5 FIG. 5 illustrates the utility of the present invention to diagnose pressure and volume components of myocardial impairment for a patient afflicted with the acute respiratory disease syndrome from an ED; FIG. 6 illustrates the utility of the present invention to diagnose cardiac efficiency of an exercising subject, to design rehabilitation and exercising programs, and to determine the intensity 5_. levels for beneficial exercise; and

FIG. 7 illustrates the utility of the present invention to diagnose myocardial impairment and dysfunction, design and monitoring of therapies, interventions, and the efficacy of drugs. 0 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1, there are displayed electromechanical signals as a function of time with each signal being a measure of a physiological parameter. The magnitudes of the electromechanical 5 signals at a specific time describe the state of the system at that time. They are called state variables. Comparing the magnitude of an electromechanical signal at a subsequent time with the magnitude of an electromechanical signal at a previous time describes 0 the change which has occurred during the time interval or the functionality. For example, if SBP denotes the maximal ventricular pressure at a previous time and EDP the minimal ventricular pressure at a later time, then EDP can be expressed as a fraction, EF_p, of SBP to 5 provide an effective pressure P_eff which describes the pressure functionality of the cardiocirculatory system during the time of one heart beat

P_eff = EF_p SBP (1) EF_p can be recognized as the cardiac pressure efficiency which indicates how well ventricular pressure is utilized.

(SBP - EDP)

5. EF_p = (2)

SBP Referring to FIG. 1, the product of ventricular pressure and volume equals ventricular energy, VE. The minimal magnitude of VE, occurring at 0 a subsequent time and given by the product of EDP and ESV, where ESV is the minimal ventricular volume, can be expressed as a fraction, CF, of the maximal VE, occurring at a prior time given by the product of SBP and EDV to derive an effective energy, VE, which is 5 converted to perform cardiac work, W

W = CF * (EDV * SBP) (3) where EDV is the maximal ventricular volume. The product of pressure efficiency, EF_p/ and volume efficiency, EF_V JJ ( EDV - ESV)

_EFy = _{( )}

EDV def ines cardiac ef f iciency, CF

CF = EF_p * EF_V ( 5 ) 5 According to the instant invention, a device and method are provided to describe functionality of the cardiocirculatory system by determining the effective values of electromechanical state variables including but not limited to the electromechanical 0 state variables noted in FIG. 1 to include ventricular and atrial volumes, cross-sectional ventricular and atrial areas, ventricular, arterial, central venous, jugular, radial, pulmonary artery, wedge, carotid and atrial pressures, and electrical signals and, additionally, the effective values of combinations of 5_. these parameters, including but not limited to ventricular, atrial, aortic energies, and work. The device and method to practice the instant invention also includes a computer to describe functionality per unit time versus functionality per event of one heart 0 beat, which can be accomplished by dividing equation (3) by the time of one heart beat, RR, or multiplication of equation (3) by the instantaneous heart rate, HR.

CP CF * (EDV * SBP * HR) (6) 5 where CP = W/RR = W*HR equals cardiac power. Noting that 1 liter of oxygen is consumed for the liberation of 4.82 kcal of energy permits conversion of VE into myocardial oxygen consumption, MV0₂. To practice the instant invention, therefore a computer is used to 0 describe functionality in terms of MV0₂.

Referring now to FIG. 2, there is shown a PD, which is a plot of efficiency with which electromechanical state variables, or combinations thereof are converted in a period of time to an 5 effective value describing functionality, according to equations (1), (3), or (6). According to the instant invention, means are provided to add isoplots of the effective values to the PD to estimate their magnitudes.

It is well known by those skilled in the art of hemodynamic diagnosis that hemodynamic state 5. variables change with age and with body size, represented by body surface area, BSA. According to the instant invention, signals are provided corresponding to establish reference values. In the preferred embodiment the body surface area, determined by weight 0 and height of a subject of the age group of 20 to 30 years, and electromechanical state variables of the same age group under resting conditions are chosen as reference since the growth process has been completed for this age group and the likelihood of age related 5 dysfunctions is minimal, for both processes require additional CP expenditure to either sustain growth or compensate a dysfunction.

Inserting body surface referenced data, published in Ciba-Geigy Scientific Tables, Ciba-Geigy 0 Corporation, Medical Education Division, West Caldwell, NJ 07006, ISBN 0-914168-54-1, 1990 for normals of the 20 to 30 years age group at rest into equations (3), (4), (5), and (6) yields basal values, for example, for the right heart EF(V) = 60%, EF(P) = 50%, CF = 30%, and 5 CP = 0.71*10⁶ erg/m²*sec and for the left heart EF(V) = 63%, EF(P) = 93%, CF = 60% and CP = 6.38*10° erg/m²*sec. The basal CP values are used as standards for right and left ventricle, respectively, and assigned a unit of 1 CMET/sec. They establish a zone of criticality for life cannot be sustained if less than the basal CP is expended. A patient becomes critically ill if CP < 1 CMET/sec. All present readings for a 5_. subject are compared with the basal readings and presented as a multiple of 1 CMET/sec.

Inserting the basal values CF = 30 % and CP = 1 CMET/sec for the right heart into equation (6) yields VE = 3.33 CMET/sec which is the basal VE of the right 0 ventricle. Upon the occurrence of a dysfunction, CP expenditure increases to compensate said dysfunction, which, according to equation (6), requires VE to increase. As a corollary, VE greater than the basal value of 3.33 CMET/sec diagnoses a dysfunction. The 5 basal values of CF and VE establish zones of criticality for diagnosis of myocardial impairment and dysfunctions. According to the instant invention, the computer estabishes the boundaries of zones of criticality in the PD as horizontal and vertical lines. 0 For example, for the right heart, the PD diagnoses myocardial impairment in the zone below the horizontal boundary line CF < 30 %, dysfunctions in the zone to the right of the vertical boundary line VE > 3.3 CMET/sec, and critical illness in the zone below the CP 5 < 1 CMET/sec isoplot.

Referring now to equation (5), according to the teachings of the instant invention, EF_V may be plotted versus EF_p in an efficiency diagram, ED, to identify the individual contributions of pressure and volume to global CF. The boundary lines of zones of criticality are identified by horizontal and vertical lines and the isoplot of CF obtained from subjects of the 20 to 30 years age group under resting conditions. According to the instant invention, the computer diagnoses a pressure-related myocardial impairment in the zone of criticality EF_p < 50 %, a volume-related myocardial impairment in the zone of criticality EF_V < 60 %, and a global myocardial impairment in the zone of criticality CF < 30 % for the right heart. Zones of criticality can be established for the left heart in a similar manner. Further a reference frame is provided to produce the zones of criticality as a function of a computer program or as a transparent overlay on the monitor.

According to the teachings of the present invention, any electromechanical state variable of the cardiocirculatory system, including but not limited to the ones listed in FIG. 1, may be denoted by A. Its effective value over a period of time, A_ef is described as a fraction, CF, of the original value A at an initial time

A_eff = CF * h ( t ) (7) Equation (7) may be referenced to BSA and converted to a per unit time event to read

A_eff/BSA CF * A(t.,)/BSA * HR (8) CF = (A(t,) - A(t₂))/A(t₁) (9) Computations by a computer are provided in the instant invention to generate PDs using the relationship found in equations (8) and (9).

The embodiment, as shown in FIG. 3 5_. illustrates the teachings of the instant invention. Accordingly, sensors 2 are placed on a subject 1 to detect signals representative of electromechanical state variables to include but not limited to ventricular and atrial volumes, cross-sectional 0 ventricular and atrial areas, ventricular, arterial, central venous, jugular, radial, pulmonary artery, wedge, carotid, and atrial pressures, electrical signals, time signals for one heart cycle, and heart rate which are transmitted on multi-line wire 3 to 5 computer 4. Such sensors 2 may include catheters, ultra-sound equipment, pressure transducers, blood pressure cuffs, and electrodes as required for differential assessment of the left or right heart electromechanical state variables. Additional input 0 representative of patient information including weight, height, body surface area, pre-selected time intervals, and pre-selected basal electromechanical state variables values is provided from a keyboard 5 to computer 4 on line 6. Computer 4 is programmed to process the incoming signals on line 6 to establish basal, BSA referenced signals for establishing boundaries for zones of criticality. Computer 4 is also programmed to process the incoming signals on line 3, to determine their magnitudes, reference them to BSA, establish their effective values over pre-selected time intervals, their efficiency in said time intervals to establish functionality. Additionally, computer 4 5_. determines whether the present effective values of the electromechanical state variables and their efficiencies of a subject lie in the zones of criticality from which myocardial impairment, dysfunction, critical illness, and physical fitness is 0 deduced. All said parameters are transmitted by line 8 to a monitor 9 which is comprised of a display 10, audible and visual alarms 11 to warn of emergencies if preset values of the parameters are attained, and indicators 12 to diagnose myocardial impairment, 5 dysfunction, critical illness, and physical fitness from the attainment of specific magnitudes of the electromechanical state variables, their efficiencies, and their effective values. Inputs from keyboard 5 may be used to select from among the various diagrams for 0 display by display 10 along with plotted points representing instant conditions of a monitored subject. The signals displayed by display 10 and the audio and visual alarms 11 and the signals displayed by indicator 12 are transmitted on line 14 to a printer 13 for 5 producing hard copies and on line 16 to a modem 15 for transmission over telephone lines to central storage. A memory 17 in the computer 4 serves as storage of all information and data. Referring now to FIGS. 4 and 5 collectively, data shown in Table 1, as published by J. W. Biondi, et al. in an article entitled The Effect of Incremental Positive End-Expiratory Pressure on Right Ventricular Hemodynamics and Ejection Fraction, Anesthesia Analgesia 1988; 67:144-151, on patients with acute respiratory disease are used to demonstrate the utility of PDs and EDs to diagnose myocardial impairment, dysfunction, and critical illness from right ventricular data.

Table 1 PEEP 0 cm H₂0 5 cm H₂0 10 cm H₂0 20 cm H₂0 v T D ■

SBP mm Hg 39 43 44 48

EDP mm Hg 6 7 6 8

EDVI ml/m² 103 92 95 113

ESVI ml/m² 60 48 55 79

HR 1/min 101 102 103 103

EF(V) % 42 48 42 30

EF(P) % 79 84 77 75

CF % 33 40 32 23

VE CMET/sec 12. 7 12.6 13.5 17.6

CP CMET/sec 4. 2 5.1 4.4 3.9

EDVI = EDV/BSA, ESVI = ESV/BSA These patients were treated with positive end- expiratory pressures (PEEP) of varying magnitudes indicated by the symbols v no PEEP, _* 5 cm H₂0 PEEP, α 10 cm H₂0 PEEP, and ■ 20 cm H₂0 PEEP. The computer 4 receives input signals representative of EDV, ESV, SBP, EDP, and HR, and input signals from keyboard 6 5. representative of basal values, processes all signals to determine zones of criticality, and instant data for subjects EF_V, EF_p, CF, VE, and CP. Subsequently, computer 4 generates a PD and an ED. According to the teachings of the instant invention, the cardiac monitor 0 of FIG. 3 by displaying the instant subject data in a PD of FIG. 4 reveals a dysfunction (in this case a respiratory disease) as VE significantly exceeds the basal VE and lies in the zone of dysfunctional criticality. No myocardial impairment is revealed by 5 the cardiac monitor for no PEEP treatment and for PEEP treatments not exceeding 10 cm H₂0 since the CFs for the respective treatments exceed the basal cardiac efficiency and reside outside the zone of myocardial criticality. Still further, the cardiac monitor 0 reveals a PEEP of 5 cm H₂0 as the most beneficial pressure to elevate CF to its highest level compared to all other PEEP treatments.

In another aspect of the teachings of the present invention, the cardiac device of FIG. 3 by 5 displaying an ED of FIG. 5, containing a data point representing an instant condition of a monitored subject, reveals depressed EF_vs which are compensated by elevated EF_ps to result in an over-all normal CF outside the zone of criticality for no PEEP treatment and PEEP treatments not exceeding 10 cm H₂0. The cardiac monitor also detects a concomitant EF_V and EF_p deterioration for PEEP of 20 cm H₂0 resulting in an 5_. abnormally low cardiac efficiency representative of myocardial impairment inside the zone of criticality. The cardiac monitor, thus, allows the design of specific therapies affecting myocardial impairment through volume efficiency and pressure efficiency, and 0 design of therapies affecting dysfunctions and the monitoring of these therapies.

Referring now to Table 2, there are listed heart rate and blood pressure data as published by R. A. Wolthuis et. al. in an article entitled, The 5 response of healthy men to treadmill exercise, Circulation 1977;55:153-157, which were used to practice the instant invention to design and monitor rehabilitation and conditioning exercise programs. Here functionality is described by determining the 0 efficiency, EF_p with which SBP is utilized at different exercise intensity levels to produce an effective pressure, P_eff to practice the instant invention to design and monitor rehabilitation and conditioning exercise programs. The increased P_eff is due to the 5 exercise as compared to the dysfunction of a patient. In the case of the exercising subject the zone above the myocardial impairment boundary line and to the right of the dysfunctional boundary line may be considered the zone of physical fitness.

Table 2 Age exer- 26 years 47 years cise

BSA [m₂] rest 1.77 2.13

SBP [mm Hg] rest 115 140

SBP(1 ) [mm Hg] sub-maximal 132 174

SBP(2) [mm Hg] sub-maximal 148 193

SBP(3) [mm Hg] sub-maximal 160 208

SBP [mm Hg] maximal 164 216

EDP [mm Hg] rest 80 90

EDP( 1) [mm Hg] sub-maximal 68 90

EDP(2) [mm Hg] sub-maximal 65 90

EDP(3) [mm Hg] sub-maximal 60 90

EDP [mm Hg] maximal 60 96

HR [1/min] rest 60 82

HR(1) [1/min] sub-maximal 102 141

HR(2) [ 1/min] sub-maximal 130 174

HR(3) [1/min] sub-maximal 158 190

HR [ 1/min] maximal 200 188

EF_p [%] rest 30 36

EF_p(l) [%] sub-maximal 48 48

EF_p(2) [%] sub-maximal 56 53

EF_p<3) [%] sub-maximal 63 57

EF_p [%] maximal 63 56

SBPI*HR [CMET/sec] rest 3.33 4.43 SBPI*HR(1) [CMET/sec] sub-maximal 6.25 9.46 SBPI*HR(2) [CMET/sec] sub-maximal 8.93 13.0 SBPI*HR(3) [CMET/sec] sub-maximal 11.73 15.2

SBPI [CMET/sec] maximal 13.3 15.7

CP [CMET/sec] rest 1.0 1.59

CP [CMET/sec] sub-maximal 3.0 4.54

CP [CMET/sec] sub-maximal 5.0 6.89

CP [CMET/sec] sub-maximal 7.39 8.66

CP [CMET/sec] maximal 8.38 8.79 10. SBPI = SBP/BSA

Referring now to the PD shown in FIG. 6, there is plotted EF_p versus SBPI*HR for the left heart for two groups of subjects of ages 26 and 47 years exercising on a treadmill. The symbols denote time on 15 the treadmill as follows v at rest prior to commencement of the treadmill test, » stage 1, sub- maximal response at a low exercise intensity, o stage 2 sub-maximal response at a higher exercise intensity, ■ stage 3 sub-maximal response at a still higher exercise 20 intensity, A maximal response at the highest exercise intensity. Subjects of the younger age group convert a smaller magnitude of SBP more efficiently as compared to the subjects of the older age group. A maximal threshold efficiency is attained prior to maximal 25 exertion. Thus, the cardiac monitor of FIG. 3 allows the design of exercise programs, for example, for cardiac rehabilitation and for competitive athletes at an exercise intensity level producing the threshold of maximum efficiency or a pre-determined EF_p to assure safety of cardiac patients and progress in the conditioning program of athletes.

Referring now to Table 3, there are listed heart rate and blood pressure data as published by A. S. Phillips et. al. in an article entitled Propofol- Fentanyl anesthesia: A comparison with Isoflurane- Fentanyl anesthesia in coronary artery bypass grafting and valve replacement surgery. Journal of Cardiothoracic and Vascular Anesthesia 1994;8:289-296, which were used to describe functionality by determining the efficiency, EF_p with which SBP is utilized pre- and post-induction of anesthesia to produce an effective pressure, EF_p to practice the instant invention to design and monitor drug therapies such as anesthesia.

Table 3 pre-anesthesia post- -anesthesia

========= :============ ======== =========== ==== ===========

BSA [m₂] 1.91 1.91

HR [1/min] 61 65

SBP [mm Hg] 127 105

EDP [mm Hg] 66 60

EF_p [ % ] 48 43

VE [CMET/sec] 3.33 2.94

CP [CMET/sec] 1.6 1.26

Referring now to FIG. 7, there is shown the PD, created by the monitor of FIG. 3 which uses left heart data from Table 3, of a group of patients in whom anesthesia is administered. Here v denotes the state prior to anesthesia and T the state after anesthesia administration by the drug Propofol-Fentanyl. The patient shows a decreased EF_p caused by the anesthesia, however, no zones of criticality are entered. Thus, the cardiac monitor has utility to design therapies and monitor efficacy of therapies, drug interventions and the safety of patients by monitoring and maintaining functionality outside of the zones of criticality. In still other embodiments of the present invention other electromechanical state variables as noted in FIG. 1 including volumes, cross-sectional areas, pressures, electrocardiographic and echocardiographic signals may be used to determine functionality from the efficiency with whiςh these variable are converted to effective values.

In yet another embodiment numerous values for electromechanical state variables and their combinations, their effective values, and efficiencies may be collected and displayed in time reference frames including the time derivatives to further monitor progress or regress of myocardial impairments and dysfunctions, critical illness, and physical fitness. While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims.

Claims

CLAIMS 1. A cardiac diagnostic device for establishing cardiac functionality of an individual over a time interval, said device including the combination of: a sensor for measuring a physiological parameter A of said individual at an initial time t₁ and at a subsequent time t₂; a computer for computing the value for A_eff corresponding to cardiac functionality according to the equation:

A_eff = (Aft.,) - A ta l * Aft,) Aft,) where: (Aft,,) - A(t ) ) = CF and Aft.,) where CF is the efficiency with which Aftl) is converted into A_eff; and a reference frame receiving a data reference value corresponding to the computed value for A_βff in relation to boundary values defining physiological criticality of cardiac fitness for assessment of cardiac functionality of such an individual.

2. The device according to claim 1 wherein the efficiency CF is plotted in the performance diagram versus the physiological parameter and wherein isoplots of A_eff are added to permit estimates of A_eff.

3. The device according to claim 2 wherein the boundary values of zones for physiological criticality and physical fitness are determined from predetermined basal values A_eff, CF, and A for a predetermined age group.

4. The cardiac diagnostic device according to claim 3 wherein the computer establishes a basal value of A_eff of 1 CMET/sec to allow expression of values of physiological parameters and effective values in terms of the basal reference of 1 CMET/sec.

5. The cardiac diagnostic device according to claim 3 wherein said computer further computes instant data points of an individual referenced to body surface area and compares the locations of said data points with respect to the zones of criticality.

6. The cardiac diagnostic device according to claim 1 wherein said physiological criticality of cardiac fitness includes zones of myocardial impairment, dysfunction, critical illness and physical fitness.

7. The cardiac diagnostic device according to claim 3 wherein said computer locates instant data points with respect to the zones of criticality to design and monitor therapies for differential treatment of myocardial impairment, dysfunctions and critical illness.

8. The cardiac diagnostic device according to claim 5 wherein said instant data points and zones of criticality are plotted in said reference frame as a function of time to allow diagnosis of progress or regress of myocardial impairment, dysfunctions, critical illness and physical fitness.

9. The cardiac diagnostic device according to claim 3 wherein said computer locates instant data points with respect to data points to establish performance diagrams for determining the outcome of interventions.

10. The cardiac diagnostic device according to claim 3 wherein said computer locates instant data points to establish performance diagrams for the evaluation of the efficacy of drugs.

11. The cardiac diagnostic device according to claim 1 wherein said sensor includes catheters, pressure transducers, pressure cuffs, electrocardiographic electrodes or echocardiographic sensors.

12. The cardiac diagnostic device according to claim 1 wherein said measurements derived by said sensors correspond to ventricular volumes; ventricular and atrial cross-sectional areas; ventricular, arterial, central venous, pulmonary artery, wedge, carotid, atrial, jugular, and radial pressures; electrocardiographic and echocardiographic signals; time for completion of one heart beat; or heart rate and combinations thereof.

13. A method of diagnosing cardiac functionality of an individual, said method including the steps of: measuring a physiological parameter A of said individual at an initial time t., and a subsequent time t₂, and computing the value for A_eff corresponding to cardiac functionality according to the equation:

A_eff = (Aft,) - A(t₂H * Aft,), and Aft,) where: (Aft,) - A(t₂) ) = CF and Aft,) where CF is the efficiency with which Aft,)is converted into A_eff; and comparing the computed value for A_eff with established boundary values defining physiological criticality of cardiac fitness to determine cardiac functionality of such an individual.

14. The method according to claim 13 wherein the step of comparing includes plotting the efficiency CF in performance diagrams versus the physiological parameter and wherein isoplots of A_βff are added to permit estimates of A_eff.

15. The method according to claim 14 including the further step of determining boundary values of zones for physiological criticality and physical fitness are determined from predetermined basal values A_βff, CF, and A for a predetermined age group.

16. The method according to claim 15 including the further step of establishing a basal value of A_βff of 1 CMET/sec to allow expression of values of physiological parameters and effective values in terms of the basal reference of 1 CMET/sec.

17. The method according to claim 15 including the further step of computing instant data points of an individual referenced to body surface area and comparing the locations of said data points with respect to the zones of criticality.

18. The method according to claim 13 wherein said step of comparing includes establishing zones of myocardial impairment, dysfunction, critical illness and physical fitness.

19. The method according to claim 15 including the further step of locating instant data points with respect to the zones of criticality to design and monitor therapies for differential treatment of myocardial impairment, dysfunctions and critical illness.

20. The method according to claim 15 including the further step of locating instant data points with respect to the zones of criticality to design and monitor rehabilitation and conditioning programs of individuals.

21. The method according to claim 15 including further steps of locating instant data points to establish performance diagrams for determining the outcome of interventions.

22. The method according to claim 15 including the further steps of locating instant data points to establish performance diagrams for the evaluation of the efficacy of drugs.

23. The method according to claim 13 wherein said step of measuring includes using catheters, pressure transducers, presβure cuffs, electrocardiographic electrodes or echocardiographic sensors.

24. The method according to claim 13 wherein said step of measuring includes deriving a signal corresponding to ventricular volumes; ventricular and atrial cross-sectional areas; ventricular, arterial, central venous, pulmonary artery, wedge, carotid, atrial, jugular, and radial pressures; electrocardiographic and echocardiographic signals; time for completion of one heart beat; or heart rate and combinations thereof.