WO2011045806A1

WO2011045806A1 - Apparatus and methods for the non-invasive measurement of aortic pressure parameters and cardiovascular system parameters.

Info

Publication number: WO2011045806A1
Application number: PCT/IN2009/000711
Authority: WO
Inventors: Vijay Suresh Naik
Original assignee: Genesis Medical Systems Pvt. Ltd.
Priority date: 2009-10-14
Filing date: 2009-12-09
Publication date: 2011-04-21

Abstract

A method and an apparatus for non-invasively measuring carotid-femoral-pulse-wave-velocity (CFPWV) of a living subject are disclosed. A plurality of cuffs are used for measuring first blood pressure parameters, a second blood pressure measuring step is carried out based on first computed and analyzed results, an electrocardiogram is recorded using an electrocardiograph, a plurality of highest voltage level waveforms is simultaneously recorded from the plurality of inflated cuffs, a time difference (T_L) between highest voltage level waveform starting points from at least two predetermined positions is determined, an averaged peripheral pulse-wave-velocity (PWV) of the living subject is determined, finally carotid-femoral-pulse-wave-velocity (CFPWV) values are calculated from averaged peripheral pulse-wave-velocity and displayed.

Description

"Apparatus and methods for the non-invasive measurement of Aortic Pressure parameters and cardiovascular system parameters."

2. APPLICANT

Name Genesis Medical Systems Pvt. Ltd.

Nationality Indian

Address Genesis Medical Systems Pvt. Ltd.

5-9-59, Suite No. : 303,

Moghul's Court Building, Basheerbagh,

Hyderabad - 500001 (AP) India.

Phone : +91 - 40 - 6450 8950 / 6450 8951

Fax : +91 - 40 - 66625145

E-mail : viiaynaik@genesismedicals.com

3. PREAMBLE TO THE DESCRIPTION

The invention relates to a method for non-invasive measurement of Aortic Pressure parameters and cardiovascular system parameters and a device for implementing the method for non-invasive measurement of Aortic Pressure parameters and cardiovascular system parameters. 4. DESCRIPTION:

Technical Field of the Invention

[0001] The invention relates to a method for non-invasive measurement of Aortic Pressure parameters and cardiovascular system parameters and a device for implementing the method for non-invasive measurement of Aortic Pressure parameters and cardiovascular system parameters.

Background of the Invention

[0002] When the left ventricle of the heart contracts and pumps blood into the Aorta, it ge erates a pressure pulse or energy wave. The blood being a non-compressible liquid, the velocity of travel of this pulse wave is related to the elasticity of the arteries. The measurement of pulse wave velocity along the arteries provides the strongest evidence concerning the prognostic significance of arterial stiffening. Arterial stiffness means arterial wall thickens and loses its elasticity. Pulse wave velocity is the velocity of a pulse wiive traveling a given distance between two sites in the arterial system. Pulse wave velocity is a well-established technique for obtaining the measurement of arterial stiffness between two locations in the arterial tree and the pulse wave velocity is dependent on the st; ness of artery. The information obtained by measuring the Pulse Wave Velocity indicates the degree of atherosclerosis. Normally the pulse wave velocity is measured between the two ends of largest artery between carotid to femoral and brachial to ankle to measure the arterial stiffness. Increased arterial pulse wave velocity has been shown to predict morbidity and mortality in cardiovascular disease like hypertension, coronary artery disease, diabetes mellitus, and end stage renal disease.

[0003] Augmentation index is used as a surrogate measure of arterial stiffness derived from the ascending aortic pressure waveform. Augmentation index is defined as the ratio of aortic augmentation pressure to the pulse pressure. Augmentation pressure describes the increase of aortic systolic blood pressure due to the early return in systole of peripheral reflected wave inflection point. [0004] One of the conventional methods of the measurement of pulse wave velocities is done by using tonometer, which measures the pressure wave inside the artery. The use of tonometer is expensive, bulky and that it requires a skilled operator to hold tonometer device in position. These methods are applicable to the only superficial arteries where the pulse is palpable.

[0005] Typically in some other method, the measurement of pulse wave velocity is measured by determining the time difference between the first periodic point related to electrocardiographic waveform and the second periodic point related to detected pulse wave. This type of measurements employs a photo-electric sensor including a light source and light sensor. Consists of two units, both require power supply and the transmitter must be aligned directly at the receiver and will fail if either part is moved out of position. Two sensors close together may experience "crosstalk" in which one sensor detects the signal from the wrong transmitter. It has a limited sensing range.

[0006] Some of the measurements use pressure pulse wave detecting probe worn around the neck portion includes a container like sensor and a fed screw which is engaged with an electric motor. The screw is rotated to move the sensor in width wise direction of a carotid artery. The subject wearing the pulse wave sensor around the neck feels tenderness or the blood flow through the blood vessels is reduced, leading to dizziness, lacking of blood flow to the brain causing a stroke, Slurred speech or inability to speak, confusion, fainting.

[0007] In some other method, the pulse wave velocity measurement is done with · reference to only one of the upper limb cuffs. It does not take other half of upper limb arterial structure into account. But the aortic root pressure parameters are dependent on the summation of pulse wave reflections from all the branches of arterial tree. Hence the pulse wave velocities calculated by this method is not helpful to find central arterial pressure parameters with high accuracy. [0008] Alternatively, an atherosclerosis inspection is related to augmentation index measurement based on the obtained pulse wave velocity related information, the measured blood pressure, the measured heart rate, pre-ejection period, and ejection time, according to a predetermined relationship between pulse wave velocity related information, blood pressure, heart rate, pre-ejection period and ejection time. This method uses the neck probe and doesn't measure the central aortic pressure parameters like systolic, diastolic and pulse pressures.

[0009] Some of the methods disclosed elsewhere are based on the assumption that the arterial stiffness affects all human subjects in equal measure. Hence these methods exxrapolate the radial pressure waveform to the aortic pressure waveform with predetermined generalized transfer function like convolution in frequency domain. This extrapolation holds good for some of the patients wherein the said assumption is true. A unique and individual transfer function for each patient is required to accurately predict the aortic waveform. Hence the generalized extrapolation may yield erroneous results.

[0010] Thus measurement of aortic pressure parameters using conventional techniques incorporate either invasive techniques, which is a painful procedure and also a root cause for infections to the patients or other techniques which involve sensors placed around the neck making the patient wearing the pulse wave sensor around the neck feel tenderness or dizziness Slurred speech or inability to speak, confusion, fainting.

[0011] Hence there is a need for an improved apparatus for non-invasive determination of Aortic root parameters and a simple method for non-invasive determination of Aortic root ^■ parameters.

Summary Of The Invention

[0012] A method and an apparatus are disclosed for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject. In accordance with an exemplary aspect of the present invention, according to a first aspect of the present invention, a method for non-invasively measuring Carotid-femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously inflating a plurality of cuffs worn on plurality of predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject.

[0013] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs by oscillometric method and a plurality of voltage level waveforms from the plurality of cu¾.

[0014] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of computing and analyzing the blood pressure parameters.

[0015] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously inflating the plurality inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time. The computed pressure parameter is a mean arterial pressure.

[0016] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of monitoring and storing an electrocardiogram using an electrocardiogram measuring unit.

[0017] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously recording a plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter.

[0018] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of analyzing the plurality highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level waveforms starting points. The at least two predetermined positions include at least one of the upper limb of the living subject on right or left side and the lower limb of the living subject on the same side.

[0019] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of determining an averaged peripheral pulse wave velocity (PWV) of the living human subject. The averaged peripheral pulse wave velocity (PWV) is obtained by averaging PWVLP and PWVRP where by

(i) PWV_Lp = D_Lp / T_LP

PWVLP - Left side peripheral arterial system pulse wave velocity measured from the left upper limb cuff to the left lower limb cuff, Aorta (central Arterial System) being common part of the path.

DLP - Superficial distance obtained by summation of a distance from the left upper

limb cuff to heart and a distance from heart to the Left lower limb cuff.

TLP - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

(ii) PWVRP = DRP / TRP

PWVRP - Right side peripheral arterial system pulse wave velocity measured from the right upper limb cuff to the right lower limb cuff, Aorta (central Arterial System) being common part of the path.

DRP - Superficial distance obtained by summation of a distance from the Right upper limb cuff to heart and a distance from heart to the Right lower limb cuff. T P - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

[0020] According to the first aspect, the method for non-invasively measuring Carotid- fenoral-pulse- wave-velocity (CFPWV) of a living human subject includes a step of determining a carotid-femoral-pulse-wave-velocity (CFPWV) value from the averaged peripheral pulse wave velocity.

[0021] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject further includes a step of displaying the carotid-femoral-pulse-wave-velocity (CFPWV) of the living human subject.

[0022] According to a second aspect, a method for non-invasively measuring Aortic Root Pressure Parameters of a living subject is disclosed. The method includes a step of simultaneously inflating a plurality of cuffs worn on predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject.

[0023] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs by oscillometric method and a plurality of voltage level waveforms from the plurality of cuffs.

[0024] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of computing and analyzing the blood pressure parameters. [0( 25] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously inflating the plurality of inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time.

[0026] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of monitoring and storing an electrocardiogram using an electrocardiogram measuring unit.

[0027] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously recording plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter.

[0028] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of analyzing the plurality of highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level waveforms starting points. The at least two predetermined positions includes at least one of the left upper limb of the living subject and the left lower limb of the living subject and the right upper limb of the living subject and the right lower limb of the living subject.

[0029] According to the second aspect, the method for non-invasively measuring Aortic · Root Pressure Parameters of a living subject includes a step of determining an averaged peripheral pulse wave velocity (PWV). The averaged peripheral pulse wave velocity(PWV) is obtained by averaging PWV_Lp and PWV_RP> whereby

(i) PWV_LP = D_LP / T_Lp

PWVLP - Left side peripheral arterial system pulse wave velocity measured from the left upper limb cuff to the left lower limb cuff, Aorta (central Arterial System) being common part of the path. D_LP - Superficial distance obtained by summation of a distance from the left upper limb cuff to heart and a distance from heart to the Left lower limb cuff.

T_LP- Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff,

(ii) PWVRP = D_RP / TRP

DRP - Superficial distance obtained by summation of a distance from the Right upper

limb cuff to heart and a distance from heart to the Right lower limb cuff.

T P - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

[0030] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of determining a carotid- femoral-pulse-wave-velocity (CFPWV) value from the averaged peripheral pulse wave velocity.

[0031] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of averaging the left upper limb pressure values and the right upper limb pressure values. Averaging the left upper limb pressure values and the right upper limb pressure values further includes (i) averaging Left arm brachial systolic pressure value and right arm brachial systolic pressure value, (ii) averaging left arm brachial diastolic pressure value and right arm · brachial diastolic pressure value and (iii) averaging left arm brachial pulse pressure value and right arm pulse pressure value.

[0032] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of determining an Aortic systolic pressure, an Aortic diastolic Pressure, an Aortic Pulse pressure, an aortic augmentation pressure and an Aortic augmentation index values from values obtained from the carotid-femoral-pulse-wave-velocity(CFPWV) and the averaged upper limb pressure values.

[0033] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject further includes a step of displaying the averaged peripheral pulse wave velocity, the Aortic systolic pressure, the Aortic diastolic Pressure, the Aortic Pulse pressure, the aortic augmentation pressure and the Aortic augmentation index values and the carotid-femoral-pulse-wave-velocity(CFPWV) of the living subject.

[0034] According to a third aspect, an apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject is disclosed. The apparatus includes a plurality of inflating means for simultaneously inflating a plurality of cuffs worn on predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject.

[0035] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a plurality of deflating valves for simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs and plurality of voltage level waveforms from the plurality of cuffs.

[0036] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a processing unit for computing and analyzing the blood pressure parameters.

[0037] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes simultaneously inflating the plurality of inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time. The computed pressure parameter is a mean arterial pressure.

[0( 38] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a means for monitoring and storing an electrocardiogram.

[0039] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes an analyzing unit for recording plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter and analyzing the plurality of highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level waveforms starting points. The at least two predetermined positions includes at least one of the left upper limb of the living subject and the left lower limb of the living subject, the right upper limb of the living subject and the right lower limb of the living subject.

[0040] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a computing unit for determining an averaged peripheral pulse wave velocity (PWV), a carotid-femoral-pulse-wave- velocity (CFPWV) and Aortic root pressure values. The aortic root pressure parameters includes an Aortic Systolic Pressure (AO-SYS), an Aortic diastolic pressure (AO-DIA), an Aortic Pulse Pressure (AO-PP), an Aortic Augmentation Pressure (AO-AUP) and an Aortic Augmentation Index (AO-AIx). The averaged peripheral pulse wave velocity■ (PWV) is obtained by averaging PWV_Lp and PWVRP_, whereby

PWLP- Left side peripheral arterial system pulse wave velocity measured from the left upper limb cuff to the left lower limb cuff, Aorta (central Arterial System) being common part of the path.

limb cuff to heart and a distance from heart to the Left lower limb cuff. TLP - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff,

(ii) PWVRP = DR_P / TRP

PWVRP- Right side peripheral arterial system pulse wave velocity measured from the right upper limb cuff to the right lower limb cuff, Aorta (central Arterial System) being common part of the path.

DR - Superficial distance obtained by summation of a distance from the Right upper limb cuff to heart and a distance from heart to the Right lower limb cuff.

TRP- Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

Brief Description of the Drawings

[0041] The invention is described in more detail below with reference to the example em Dodiments and with the aid of the figures, only the features required to understand the invention being illustrated.

[0042] FIG. 1 is a diagram depicting a transmission of pressure waves in the arteries.

[0043] FIG.2A is a diagram depicting pulse wave velocity measurements at a proximal carotid site and a distal radial site.

[0044] FIG.2B is a diagram depicting pulse wave velocity measurements at a proximal carotid site and distal femoral site.

[0045] FIG.2C is a diagram depicting pulse wave velocity measurements at proximal brachial site and distal ankle site.

[0046] FIG. 3 A is a diagram depicting the reflection of pressure waves emanating from aortic root from various branches of arterial tree.

[0047] FIG. 3B is a diagram depicting normal pulse wave velocity with a normal arterial stiffness.

[0048] FIG. 3C is a diagram depicting increased pulse wave velocity with increased arterial stiffness.

[0049] FIG. 4 is a diagram depicting a cuff placement and pneumatic circuit. [0050] FIG. 5 is a flowchart depicting a process in accordance with exemplary aspect of the present invention.

[0( 51] FIG. 6 is a diagram depicting system components in accordance with exemplary aspect of the present invention.

Detailed Description of Invention

[0052] Exemplary embodiments of the present invention are directed towards a method and an apparatus for non-invasively measuring Carotid-femoral-pulse-wave-velocity (CFPWV) of a living human subject. In accordance with an exemplary aspect of the present invention, according to a first aspect of the present invention, a method for non- invasively measuring Carotid-femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously inflating a plurality of cuffs worn on plurality of predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject.

[0053] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave- velocity (CFPWV) of a living human subject includes a step of simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs by osciUometric method and a plurality of voltage level waveforms from the plurality of cuffs.

[0054] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave- velocity (CFPWV) of a living human subject includes a step of computing and analyzing the blood pressure parameters.

[0055] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously inflating the plurality inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time. The computed pressure parameter is a mean arterial pressure.

[0056] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of monitoring and storing an electrocardiogram using an electrocardiogram measuring unit.

[0057] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of simultaneously recording a plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter.

[0058] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse- wave- velocity (CFPWV) of a living human subject includes a step of analyzing the plurality highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level waveforms starting points. The at least two predetermined positions include at least one of the upper limb of the living subject on right or left side and the lower limb of the living subject on the same side.

[0(59] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse-wave-velocity (CFPWV) of a living human subject includes a step of determining an averaged peripheral pulse wave velocity (PWV) of the living human subject. The averaged peripheral pulse wave velocity (PWV) is obtained by averaging PWVLP and PWVRP where by

(i) PWVLP = D_LP / T_Lp

PWVLP - Left side peripheral arterial system pulse wave velocity measured from the left upper limb cuff to the left lower limb cuff, Aorta (central Arterial System) being common pail of the path.

DLP - Superficial distance obtained by summation of a distance from the left upper limb cuff to heart and a distance from heart to the Left lower limb cuff.

T_Lr - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff,

(ii) PWVRP = DRP / TR_P

PWV_Rp - Right side peripheral arterial system pulse wave velocity measured from the right upper limb cuff to the right lower limb cuff, Aorta (central Arterial System) being common part of the path.

limb cuff to heart and a distance from heart to the Right lower limb cuff.

TR · - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

[0060] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse- wave- velocity (CFPWV) of a living human subject includes a step of determining a carotid-femoral-pulse-wave-velocity (CFPWV) value from the averaged peripheral pulse wave velocity.

[0061] According to the first aspect, the method for non-invasively measuring Carotid- femoral-pulse- wave- velocity (CFPWV) of a living human subject further includes a step of displaying the carotid-femoral-pulse-wave-velocity (CFPWV) of the living human subject.

[0062] According to a second aspect, a method for non-invasively measuring Aortic Root Pressure Parameters of a living subject is disclosed. The method includes a step of , simultaneously inflating a plurality of cuffs worn on predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject. [0063] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs by oscillometric method and a plurality of voltage level waveforms from the plurality of cuffs.

[0064] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of computing and analyzing the blood pressure parameters.

[0065] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously inflating the plurality of inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time.

[0066] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of monitoring and storing an electrocardiogram using an electrocardiogram measuring unit.

[0057] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of simultaneously recording plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter.

[0058] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of analyzing the plurality of highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level wa eforms starting points. The at least two predetermined positions includes at least one of the left upper limb of the living subject and the left lower limb of the living subject and the right upper limb of the living subject and the right lower limb of the living subject.

[0059] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of determining an averaged peripheral pulse wave velocity (PWV). The averaged peripheral pulse wave velocity(P WV) is obtained by averaging PWVLP and PWVR_P> whereby

(i) PWV_Lp = D_LP / T_Lp

P^"\?n _Lp _ Left side peripheral arterial system pulse wave velocity measured from the left upper limb cuff to the left lower limb cuff, Aorta (central Arterial System) being common part of the path.

limb cuff to heart and a distance from heart to the Left lower limb cuff.

PV ^'VRP - Right side peripheral arterial system pulse wave velocity measured from the right upper limb cuff to the right lower limb cuff, Aorta (central Arterial System) being common part of the path.

DR_P - Superficial distance obtained by summation of a distance from the Right upper limb cuff to heart and a distance from heart to the Right lower limb cuff.

TR - Time difference between pressure waveforms obtained from the left upper limb cuff and the left lower limb cuff.

[0C 60] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of determining a carotid- femoral-pulse-wave-velocity (CFPWV) value from the averaged peripheral pulse wave velocity.

[0061 ] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of averaging the left upper limb pressure values and the right upper limb pressure values. Averaging the left upper limb pressure values and the right upper limb pressure values further includes (i) averaging Left arm brachial systolic pressure value and right arm brachial systolic pressure, (ii) averaging left arm brachial diastolic pressure and right arm brachial diastolic pressure and (iii) averaging left arm brachial pulse pressure and right arm pulse pressure.

[0062] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a step of determining an Aortic systolic pressure, an Aortic diastolic Pressure, an Aortic Pulse pressure, an aortic augmentation pressure and an Aortic augmentation index values from values obtained from the carotid-femoral-pulse-wave-velocity(CFPWV) and the averaged upper limb pressure values.

[0063] According to the second aspect, the method for non-invasively measuring Aortic Root Pressure Parameters of a living subject further includes a step of displaying the averaged peripheral pulse wave velocity, the Aortic systolic pressure, the Aortic diastolic Pressure, the Aortic Pulse pressure, the aortic augmentation pressure and the Aortic auf mentation index values and the carotid-femoral-pulse-wave-velocity(CFPWV) of the living subject.

[0064] According to a third aspect, an apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject is disclosed. The apparatus includes a ¹ plurality of inflating means for simultaneously inflating a plurality of cuffs worn on predetermined positions of the living subject to a predetermined pressure. The predetermined positions for wearing the plurality of cuffs includes a left upper limb of the living subject, a right upper limb of the living subject, a left lower limb of the living subject and a right lower limb of the living subject. [0065] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a plurality of deflating valves for simultaneously deflating the plurality of inflated cuffs and recording a plurality of systolic pressure values and diastolic pressure values from the plurality of cuffs and plurality of voltage level waveforms from the plurality of cuffs.

[0066] According to the third aspect, the apparatus for non-invasively measuring Aortic »«««·

Root Pressure Parameters of a living subject includes a processing unit for computing and analyzing the blood pressure parameters.

[0067] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes simultaneously inflating the plurality of inflating cuffs worn on the predetermined positions of the living subject to a computed pressure parameter for a predetermined time. The computed pressure parameter is a mean arterial pressure.

[0068] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a means for monitoring and storing an electrocardiogram.

[0069] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes an analyzing unit for recording plurality of highest voltage level waveforms from the plurality of cuffs inflated at the computed pressure parameter and analyzing the plurality of highest voltage level waveforms starting points from the at least two predetermined positions and determining a time difference(TL) between the highest voltage level waveforms starting points. The at least two predetermined positions includes at least one of the left upper limb of the living subject and the left lower limb of the living subject, the right upper limb of the living subject and the right lower limb of the.living subject. [0070] According to the third aspect, the apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject includes a computing unit for determining an averaged peripheral pulse wave velocity (PWV), a carotid-femoral-pulse-wave- velocity (CFPWV) and Aortic root pressure values. The aortic root pressure parameters includes an Aortic Systolic Pressure (AO-SYS), an Aortic diastolic pressure (AO-DIA), an Aortic Pulse Pressure (AO-PP), an Aortic Augmentation Pressure (AO-AUP) and an Aortic Augmentation Index (AO-AIx). The averaged peripheral pulse wave velocity(PWV) is obtained by averaging PWVLP and PWVRP_, whereby

(i) PWV_Lp = D_LP / T_Lp

limb cuff to heart and a distance from heart to the Left lower limb cuff.

(ii) PWV_RP = D_RP / TRP

DRP - Superficial distance obtained by summation of a distance from the Right upper limb cuff to heart and a distance from heart to the Right lower limb cuff.

Referring to FIG. 1 is a diagram 100 depicting a transmission of pressure waves in the arteries. Accordingly the artery 102 includes a brachial artery and the artery 104 includes a radial artery. The pulse wave at the proximal site brachial artery 102 is recorded at time Tl and the same pulse wave transmitted to the distal site of radial artery 104 at time T2 is recorded and the distance D between the proximal site and the distal site is measured for determining pulse wave velocity (Vpw) between the proximal site and the distal site. The pulse wave velocity (Vpw) is calculated by using the equation:

Vpw = D / (T2-Tl).

T2 - Tl : Pulse transit time.

[0071] Referring to FIG.2A is a diagram 200A depicting pulse wave velocity measurement at a proximal carotid site and a distal radial site. The distance Dl between the heart to the proximal carotid site 202 and the distance D2 between the heart to distal radial site 204 are measured. The pulse wave transmitted at proximal carotid site 202 at time Tl and the pulse wave transmitted to distal radial site 204 at time T2 are measured respectively. The pulse wave velocity VCR between proximal carotid site 202 and distal radial site 204 is determined by the following equation:

VCR = (D1 + D2) / (T2 - T1).

[0072] Referring to FIG.2B is a diagram 200B depicting pulse wave velocity measurement at a proximal carotid site and distal femoral site. The distance D3 between the heart to the proximal carotid site 206 and the distance D4 between the heart to the distal femoral site 208 are measured. The pulse wave transmitted at proximal carotid site 206 at time T3 and the pulse wave transmitted to distal femoral site 208 at time T4 are measured respectively. The pulse wave velocity VCF between proximal carotid site 206 and distal femoral site 208 is determined by the following equation:

VCF= (D3 + D4) / (T4 - T3).

[0073] Referring to FIG.2C is a diagram 200C depicting pulse wave velocity measurements at proximal brachial site and distal ankle site. Accordingly the inflating cuffs 214 and 216 are placed at the brachial site 210 and the ankle site 212.The distance D5 between the heart to the brachial site 210 and the distance D6 between the heart to the distal ankle site 212 are measured. The pulse wave transmitted at brachial site 210 at time T5 and the pulse wave transmitted to distal ankle site 208 at time T6 are measured respectively. The pulse wave velocity VBA between brachial site 210 and distal ankle site 208 is determined by the following equation: V_BA= (D5 + D6) / (T6 - T5).

[0074] Referring to FIG. 3A is a diagram 300A depicting the reflection of pressure waves emanating from aortic root from various branches of arterial tree. The blood from left ventricle 302 is pumped into the arterial system with an Incident Pressure PL The pressure exerted at the Aortic Root 304 comprising the summation of Incidence Pressure and Reflected Pressure PR which is described in detail below.

[0075] Since the arterial system is a close ended system, the pressure wave emanating from aortic root is reflected back from various branches and vascular bed 306 of arterial tree. The resultant pressure gradient at aortic root is the summation of all the reflected waves with the incident wave. If arterial stiffness is increased, the pulse wave velocity increases and hence the time taken by the reflected wave to reach the aortic root decreases. The phase difference between the incident and reflected wave decreases significantly, superimposing them. Thus the resultant Aortic pressure (AoP) gradient and augmentation pressure increase in proportion to Pulse wave velocity. Resultant Pressure AoP= PI + PR

PI = Incident Pressure

PR = Reflected Pressure

PR = Prl+Pr2+Pr3+...+Prn, Wherein Prl, Pr2....Prn are the reflected pressures from branched arteries.

[0076] Referring to FIG. 3B is a diagram 300B depicting normal pulse wave velocity with a normal arterial stiffiiess. During the incident wave, the pressure gradient is experienced during the systolic phase and the reflected wave pressure is observed during ' the end of systole phase and before the end of diastole phase. The entire resultant pressure gradient obtained during incident wave pressure phase and reflected wave pressure phase is depicted in resultant pressure gradient waveform 308.

[0077] Referring to FIG. 3C is a diagram 300C depicting increased pulse wave velocity with increased arterial stiffiiess. The arterial stiffness is increased by applying external pressure on the arteries and is achieved by placing a cuff over an artery and inflating the cuff to a sufficient pressure where the voltage oscillations induced are maximum. During the incident wave, the pressure gradient is experienced during the systolic phase and the reflected wave pressure is observed during the end of systole phase and before the end of diastole phase. The entire resultant pressure gradient obtained during incident wave pressure phase and reflected wave pressure phase is depicted in resultant pressure gradient waveform 310. It is observed that in the resultant pressure gradient the systolic peak is increased due to the superimposition of the reflected wave pressure on to the systole. The difference between the peak systole pressure at normal condition and at increased arterial stiffness condition is determined as Augmentation pressure.

[0078] Referring to FIG. 4 is a diagram 400 depicting a cuff placement and pneumatic circuit in accordance with an exemplary aspect of the present invention. Right upper limb cuff 402, left lower limb cuff 408 and right lower limb cuff 406 are connected to respective pneumatic block 410, pneumatic block 412 and pneumatic block 414 respectively for timely inflating and deflating the cuffs and obtain blood pressure related parameters using oscillometric method. Hereinafter all the Right upper limb cuff 402, left lower limb cuff 408, right lower limb cuff 406 and left upper limb cuff 404 are termed as blood pressure cuffs 402, 404, 406 and 408 and all the limbs comprises of both upper and lower limbs.

[0079] Referring to FIG. 5 is a flow chart 500 depicting the entire process for obtaining the Aortic root parameters in accordance with an exemplary aspect of the present invention. Step 504 describes measurement of superficial distances between heart and the cuffs. The superficial measurement of distances is made by a measurement tape. The ^ distances between arm cuffs to heart and heart to ankle are superficially measured and then entered into the computer system. The next process steps comprising of:

Step 506: The first run, wherein all the blood pressure cuffs 402, 404, 406 and 408 are inflated and deflated slowly. Systolic, Diastolic and Mean Arterial Pressure for all four limbs are determined by using conventional oscillometric method.

Left arm pressure values:

LASYS - Left Arm systolic value LAD_IA - Left Arm Diastolic Value

LAM_AP - Left arm Mean Arterial Pressure value

Right arm pressure values:

RA_SYS - Right Arm systolic value.

RA_DIA - Right Arm Diastolic Value.

RAMA_P - Right arm Mean Arterial Pressure value.

Right Leg pressure values:

RLsYs - Right Leg systolic value.

RL_DI_A - Right Leg Diastolic Value.

RL A_P - Right Leg Mean Arterial Pressure value.

Left Leg pressure values:

LL_SYS - Left Leg systolic value

LLD_IA - Left Leg Diastolic Value

LL_MAP - Left Leg Mean Arterial Pressure value

Step 508: storing the systolic pressures, diastolic pressures and mean arterial pressure values of all the limbs respectively.

Step 510: wait for predetermined time. (2 to 6 Minutes, for example)

Step 512: Second Run- Inflate all the blood pressure cuffs 402, 404, 406 and 408 to respective systolic pressures.

Step 514: Deflate all the blood pressure cuffs 402, 404, 406 and 408 slowly.

Step 516, Step 518, Step 520, Step 522: All the blood pressure cuffs 402, 404, 406 and 408 are to be maintained at respective mean arterial pressures of the limbs. Step 516, Step 518, Step 520, Step 522 verify and ensure that the pressure in all the blood pressure cuffs 402, 404, 406 and 408 are at their respective mean arterial pressures i.e.

Pressure in Blood pressure cuff 402 = RA_MAP

Pressure in Blood pressure cuff 404 = LA_MAP

Pressure in Blood pressure cuff 406 = RLMA_P

Pressure in Blood pressure cuff 408 = LLMAP

Step 524, Step 526, Step 528 and Step 530: stops the deflation in all the blood pressure cuffs 402, 404, 406 and 408 and hold the pressure at a level such that:

Pressure in Blood pressure cuff 402 = RAMAP Pressure in Blood pressure cuff 404 = LAMAP

Pressure in Blood pressure cuff 406 = RLMAP

Pressure in Blood pressure cuff 408 = LL_MAP

Step 534: Save waveform data of 2 ECG leads and 4 limbs pressure waves for

predetermined period.

Step 536: Filter and analyze data for systolic wave starting point of all 4 limbs pressures. Step 538: Timing difference of systolic wave starting point of respective upper to lower limb pressure waveforms are determined. Upper to lower limb pulse wave velocities on both sides (Left and right) by dividing the respective distance with timing difference. Referring to FIG.2C the pulse wave velocity measurements are disclosed for proximal brachial site and distal ankle site. Accordingly the inflating cuffs 214 and 216 are placed at the brachial site 210 and at the ankle site 212. The distance D5 between the heart to the brachial site 210 and the distance D6 between the heart to the distal ankle site 212 are measured superficially. The pulse wave starting point at brachial site 210 at time T5 and the pulse wave starting point at distal ankle site 208 at time T6 are measured respectively. The pulse wave velocity V_BA between brachial site 210 and distal ankle site 208 is determined by the following equation:

VBA= (D5 + D6) / (T6 - T5).

Referring to FIG.4 the pulse wave velocities of right brachial site to right ankle site (VRBA) and left brachial site to left ankle site (VLBA) are determined by:

VRBA= (D11 + D12) / (T8 - T7).

VLBA= (D13 + D14) / (T10 - T9).

Step 540: Average both sides upper limb to lower limb pulse wave velocities

PWV= (V_RBA + V_LBA)/2

Carotid femoral pulse wave velocity (CF-PWV) is determined by the following equation: CF-PWV = k * PWV + C, Wherein

k - Coefficient of proportion between carotid femoral PWV and upper to lower limb PWV

C - Numerical constant k and C are obtained by regression analysis of aortic root parameters obtained from a statistically significant set of population by standard ultrasonography methods of CFPWV measurement.

Step 544: Average right and left brachial pressures:

Br_SYs= (LASYS + RA_SYSV 2

Br_DiA= (LADIA + RADIAV 2

Br_PP= [(LASYS - LADIA ) + (RASYS - RADIA)] / 2

Wherein, Left arm pressure values:

LASYS - Left Arm systolic value

LADIA - Left Arm Diastolic Value

LAMAP - Left arm Mean Arterial Pressure value

Right arm pressure values:

RASYS - Right Arm systolic value.

RADIA - Right Arm Diastolic Value.

RA AP - Right arm Mean Arterial Pressure value.

The Aortic root parameters are determined by:

AOSYS = al * Brs_Ys + bl *CF-PWV + cl

Aop_P= a2 * Br_Pp + b2*CF-PWV + c2

Ao_DiA= AOSYS - AOpp

AOAUG Pressure = a3 * Br_PP + b3*CF-PWV + c3

AOAUG Index = (AO_AUG Pressure / Aop_P) * 100

Wherein

AOSYS : Aortic Systolic Pressure

Aopp : Aortic Pulse Pressure

AODIA: Aortic Diastolic Pressure

AOAUG Pressure: Aortic Augmentation Pressure

AOAUG Index: Aortic Augmentation Index

al, a2, a3, bl, b2 and b3 are amplification coefficients and cl, c2 and c3 are corrective coefficients obtained by regression analysis of aortic root parameters obtained from a statistically significant set of population in both invasive method and non-invasive techniques. Step 546: Displays all results. Display device can be a computer screen, a printer or any other device capable of displaying the obtained parameters.

[0080] Referring to FIG. 6 is a diagram 600 depicting system components in accordance with exemplary aspect of the present invention. Console 606 is connected with an External AC Power supply 604. Console 606 comprises of an ECG Module 608 and BP Modules 612, 616, 620 and 624. ECG Module 608 is connected to the Master module 632. ECG Module 608 is a 4 lead ECG Module with 3 channel amplifiers. ECG Module 608 records ECG Waveform and heart rate of the patient during blood pressure measurements. BP Modules comprises of pressure hoses 614, 618, 622 and 626 for connecting to Blood pressure measurement cuffs. BP Modules 612, 616, 620 and 624 further comprises of pneumatic pump and valves not shown in the figure for inflating and deflating the blood pressure measurement cuffs and controlling and maintaining the cuff pressures at the desired pressures respectively. All the BP Modules 612, 616, 620 and 624 and ECG Module 632 are connected to Master module 632 for measurement of all limb pressure values and determine the average brachial pressure values, both limb pulse wave velocity values, Carotid-femoral-Pulse-wave-velocity and Aortic root pressure parameters. The master module 632 sends the determined parameters such as all limb pressure values and determine the average brachial pressure values, both limb pulse wave velocity values, Carotid-femoral Pulse wave velocity and Aortic root pressure parameters to a display unit 602. The power control 630 controls the power supply to various modules according to the instructions received from Master Module 632.

[0081] A Personal Computer 602, is the brain of the complete system. It has dedicated ' application software to run the entire system. It also acts as an input-output device for the system. The user can enter the details of subject undergoing the test like height, weight, age, sex and the like. The test is controlled by the software in the personal computer 602. It signals the dedicated hardware's master module 632 to start test with the user input and to end the test when the requisite physiological data from the dedicated data is obtained. It calculates the final results using the algorithm in Fig.5 and displays the results on the screen. The results may be printed using a printer connected to personal computer (not shown in the figure).The interface link 636 is used as the communication channel between the personal computer and the dedicated hardware.

[0082] The dedicated system 600 includes a AC to DC power supply 628. The system being a medical device incorporating ECG, this device should be electrically safe to the subjects undergoing test. This is achieved by using optically isolated AC to DC switch mode power supply. This power supply converts externally available AC voltage supply (of 110V, 60Hz or 230V, 50Hz AC for example) to the DC voltages (+12V.-12V, +5V,- 5V and the like) required by the hardware. Being optically isolated, the power supply 602 is safe for ECG.

[0083] The dedicated system 600 further includes a power control 630.The physiological parameters modules 608,612,616,620 and 624 require various power supplies (for example - +12V,-12V, +5V,-5V and the like). These power supplies need not be

Ϊ

powered on at all times since the tests are intermittent and the physiological modules need not be turned on when the test is not going on. This helps in minimizing the power requirement of the hardware. The master module with communication interface and control 632 determines when a test is underway and signals the power control module 630 to switch on the power supplies when the test is started and switch off the power supplies when the test is finished. This power control module 630 has a built-in electrically controlled switching elements. The controlled switching elements include relays, solid state switches and the like. These switching elements turn on or off the power as per the signal.

[0084] Although particular embodiments of the present invention have been shown and described, modification may be made to the device and/or method without departing from the spirit and scope of the present invention. The terms used in describing the invention are used in their descriptive sense and not as terms of limitations.

Claims

5. CLAIMS What is claimed is:

1. A Method for non-invasively measuring Carotid-femoral-pulse- wave- yelocity(CFPWV) of a living human subject, the steps comprising of:

(a) simultaneously inflating a plurality of cuffs worn on plurality of predetermined positions of said living subject to a predetermined pressure;

(b) simultaneously deflating said plurality of inflated cuffs and recording:

(i) a plurality of systolic pressure values and diastolic pressure values from plurality of said cuffs by oscillometric method ;

(ii) a plurality of voltage level waveforms from plurality of said cuffs;

(c) computing and analyzing said blood pressure parameters;

(d) simultaneously inflating plurality of said inflating cuffs worn on said predetermined positions of said living subject to a computed pressure parameter for a predetermined time;

(e) monitoring and storing an electrocardiogram using an electrocardiogram measuring unit;

(f) simultaneously recording a plurality of highest voltage level waveforms from plurality of said cuffs inflated at said computed pressure parameter;

(g) analyzing plurality of said highest voltage level waveforms starting points from at least two said predetermined positions and determining a time difference(T_L) between said highest voltage level waveforms starting points;

(h) determining an averaged peripheral pulse wave velocity(PWV) of said living human subject;

(i) determining a carotid-femoral-pulse-wave-velocity(CFPWV) value from said averaged peripheral pulse wave velocity; and

(j) displaying said carotid-femoral-pulse-wave-velocity(CFPWV) of said living human subject.

2. The method according to claim 1, said plurality of cuffs worn on said predetermined positions, wherein said predetermined positions comprising of: a left upper limb of said living subject;

a right upper limb of said living subject;

a left lower limb of said living subject; and

a right lower limb of said living subject.

3. The method according to claim 1, wherein said computed pressure parameter is a mean arterial pressure.

4. The method according to claiml, wherein said at least two said predetermined positions comprising at least one of:

said left upper limb of said living subject and said left lower limb of said living subject; and

said right upper limb of said living subject and said right lower limb of said living subject.

5. The method according to claiml, wherein said averaged central pulse wave velocity(PWV) is obtained by averaging PWVLP and PWVRP : whereby

(i) PWVLP = D_LP / T_Lp

PWVLP - Left side peripheral arterial system pulse wave velocity measured from said left upper limb cuff to said left lower limb cuff; Aorta (central Arterial System) being common part of the path;

D P - Superficial distance obtained by summation of a distance from said left upper limb cuff to heart and a distance from heart to said Left lower limb cuff; and TLP- Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff;

(ii) PWVRP = DRP / TRP

PWVRP - Right side peripheral arterial system pulse wave velocity measured from said right upper limb cuff to said right lower limb cuff; Aorta (central Arterial System) being common part of the path;

DR_P - Superficial distance obtained by summation of a distance from said Right upper limb cuff to heart and a distance from heart to said Right lower limb cuff; and T P- Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff.

6. A Method for non-invasively measuring Aortic Root Pressure Parameters of a living subject, the steps comprising of:

(a) simultaneously inflating a plurality of cuffs worn on a predetermined positions of said living subject to a predetermined pressure;

(b) simultaneously deflating said plurality of inflated cuffs and recording:

(i) a plurality of systolic pressure values and diastolic pressure values from plurality of said cuffs by oscillometric method;

(ii) a plurality of voltage level waveforms from plurality of said cuffs;

(c) computing and analyzing said blood pressure parameters;

(f) simultaneously recording plurality of highest voltage level waveforms from plurality of said cuffs inflated at said computed pressure parameter;

(g) analyzing plurality of said highest voltage level waveforms starting points from at least two said predetermined positions and determining a time difference(TL) between said highest voltage level waveforms starting points;

(h) determining an averaged peripheral pulse wave velocity(PWV);

(i) determining a carotid-femoral-pulse-wave-velocity(CFPWV) value from said averaged peripheral pulse wave velocity;

(j) averaging said left upper limb pressure values and said right upper limb pressure values;

(k) determining an Aortic systolic pressure, an Aortic diastolic Pressure, an Aortic Pulse pressure, an aortic augmentation pressure and an Aortic augmentation index values from values obtained from said carotid-femoral-pulse-wave-velocity(CFPWV) and said averaged upper limb pressure values; and (1) displaying said averaged Peripheral pulse wave velocity, said Aortic systolic pressure, said Aortic diastolic Pressure, said Aortic Pulse pressure, said aortic augmentation pressure and said Aortic augmentation index values and said carotid-femoral-pulse-wave- velocity(CFPWV) of said living subject.

7. The method according to claim 6, said plurality of cuffs worn on said predetermined positions, wherein said predetermined positions comprising of

a left upper limb of said living subject;

a right upper limb of said living subject;

a left lower limb of said living subject; and

a right lower limb of said living subject.

8. The method according to claim 6, wherein said computed pressure parameter is a mean arterial pressure.

9. The method according to claim 6, wherein said at least two said predetermined positions comprising at least one of:

10. The method according to claim 6, wherein said averaged Peripheral pulse wave velocity(PWV) is obtained by averaging PWV_LP and PWVRP : whereby

(i) PWV_Lp = D_LP / T_LP

DLP - Superficial distance obtained by summation of a distance from said left upper limb cuff to heart and a distance from heart to said Left lower limb cuff; and T_Lp- Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff;

(ii) PWVRP = DR_P / TRP

PWVRP- Right side peripheral arterial system pulse wave velocity measured from said right upper limb cuff to said right lower limb cuff; Aorta (central Arterial System) being common part of the path;

DR - Superficial distance obtained by summation of a distance from said Right upper limb cuff to heart and a distance from heart to said Right lower limb cuff; and TRP - Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff.

11. The method according to claim 6, wherein averaging said left upper limb pressure values and said right upper limb pressure values further comprising of:

(i) averaging Left arm brachial systolic pressure value and right arm brachial systolic pressure;

(ii) averaging left arm brachial diastolic pressure and right arm brachial diastolic pressure; and

(iii) averaging left arm brachial pulse pressure and right arm pulse pressure.

12. An apparatus for non-invasively measuring Aortic Root Pressure Parameters of a living subject, the steps comprising of:

(a) a plurality of inflating means for simultaneously inflating a plurality of cuffs worn on a predetermined positions of said living subject to a predetermined pressure;

(b) a plurality of deflating valves for simultaneously deflating said plurality of inflated cuffs and recording:

(i) a plurality of systolic pressure values and diastolic pressure values from plurality of said cuffs; and

(ii) a plurality of voltage level waveforms from plurality of said cuffs;

(c) a processing unit for computing and analyzing said blood pressure parameters; (d) simultaneously inflating plurality of said inflating cuffs worn on said predetermined positions of said living subject to a computed pressure parameter for a predetermined time;

(e) means for monitoring and storing an electrocardiogram;

(f) an analyzing unit for recording plurality of highest voltage level waveforms from plurality of said cuffs inflated at said computed pressure parameter and analyzing plurality of said highest voltage level waveforms starting points from at least two said predetermined positions and determining a time difference(TL) between said highest voltage level waveforms starting points; and

(g) a computing unit for determining an averaged peripheral pulse wave velocity(PWV), a carotid-femoral-pulse-wave- velocity(CFPWV), Aortic root pressure values.

13. An apparatus according to claim 12, said plurality of cuffs worn on said

predetermined positions, wherein said predetermined positions comprising of

a left upper limb of said living subject;

a right upper limb of said living subject;

a left lower limb of said living subject; and

a right lower limb of said living subject.

14. An apparatus according to claim 12, wherein said computed pressure parameter is a mean arterial pressure.

15. An apparatus according to claim 12, wherein said at least two said predetermined positions comprising at least one of:

16. An apparatus according to claim 12, wherein said averaged Peripheral pulse wave velocity(PWV) is obtained by averaging PWV_Lp and PWV_RP : whereby (i) PWVLP = DLP / T_LP

PWV_Lp- Left side peripheral arterial system pulse wave velocity measured from said left upper limb cuff to said left lower limb cuff; Aorta (central Arterial System) being common part of the path;

DLP - Superficial distance obtained by summation of a distance from said left upper limb cuff to heart and a distance from heart to said Left lower limb cuff; and TLP- Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff;

(ii) PWVRP = DR_P / TRP

DRP - Superficial distance obtained by summation of a distance from said Right upper limb cuff to heart and a distance from heart to said Right lower limb cuff; and TRP - Time difference between pressure waveforms obtained from said left upper limb cuff and said left lower limb cuff.

17. An apparatus according to claim 12, wherein said Aortic root pressure parameters comprises:

an Aortic Systolic Pressure (AO-SYS), an Aortic diastolic pressure(AO-DIA), an Aortic Pulse Pressure (ΑΟ-ΡΡ), an Aortic Augmentation Pressure (AO-AUP) and an Aortic Augmentation Index (AO-AUI).

6. DATE AND SIGNATURE: