Method and apparatus for monitoring and diagnosing hypertension and congestive heart failure

Claim 1

A congestive heart failure monitor comprising: RAM means for storing data; input means for receiving and storing a cardiac output transducer means for converting an arterial pressure to a corresponding electrical analog signal; analog to digital converter means for receiving said analog signal and digitizing it at a predetermined sampling rate; means for storing digitized samples produced by said converter means in said RAM means, said samples being stored over a time interval so that one or more pressure waves, each corresponding to a beat of the human heart, are digitized and stored in said RAM means as a series data bytes, each byte representing the instantaneous pressure of the arterial pressure; means for determining a mean arterial pressure value from said stored data bytes and storing said value; means for determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said waves and from said stored mean arterial pressure value and said stored cardiac output value; means for testing said C 2 value against a predetermined threshold value of approximately 0.07 ml/mm Hg indicative of a congestive heart failure condition and identifying a congestive heart failure condition for C 2 values below said threshold; and means for indicating said identified condition to a user of said vascular compliance monitor.

Claim 6

A method of diagnosing congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure using a transducer, said transducer producing an electrical analog signal corresponding to said arterial pressure; (c) sampling said analog signal over time at a predetermined sampling rate to provide a series of values representing one or more pressure waves each corresponding to a beat of the human heart; (d) determining the mean arterial pressure from said series of values; (e) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves as represented by said series of values and from said mean arterial pressure and cardiac output value; and (f) testing said C 2 value against a predetermined threshold value below which C 2 values are associated with a congestive heart failure condition whereby a CHF condition may be identified.

Claim 7

A method of diagnosing congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure using a transducer, said transducer producing an electrical analog signal corresponding to said arterial pressure; (c) sampling said analog signal over time at a predetermined sampling rate to provide a series of values representing one or more pressure waves each corresponding to a beat of the human heart; (d) determining the mean arterial pressure from said series of values; (e) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves as represented by said series of values and from said mean arterial pressure and cardiac output value; and (f) testing said C 2 value against a predetermined threshold value below which C 2 values are associated with a congestive heart failure condition whereby a CHF condition may be identified.

Claim 10

A method for monitoring congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring an arterial pressure using a transducer, said transducer producing an electrical analog signal corresponding to said arterial pressure; (c) sampling said analog signal over time at a predetermined sampling rate to provide a series of values representing one or more pressure waves each corresponding to a beat of the human heart; (d) determining the mean arterial pressure from said series of values; (e) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves as represented by said series of values and from said mean arterial pressure and cardiac output value; (f) recording said determining C 2 value; (g) repeating steps (a) through (f) at successive times to accumulate a plurality of recorded C 2 values over a period of time; (h) comparing the first of said accumulated C 2 values against a predetermined diagnostic threshold value discriminating between C 2 values associated with a healthy condition; (i) identifying an improving congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending toward said threshold value; (j) identifying an improving healthy trend away from a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending away from said threshold value; (k) identifying a deteriorating congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending away from said threshold value; and (1) identifying a trend toward a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending toward said threshold value.

Claim 11

A method for monitoring congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring an arterial pressure using a transducer, said transducer producing an electrical analog signal corresponding to said arterial pressure; (c) sampling said analog signal over time at a predetermined sampling rate to provide a series of values representing one or more pressure waves each corresponding to a beat of the human heart; (d) determining the mean arterial pressure from said series of values; (e) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves as represented by said series of values and from said mean arterial pressure and cardiac output value; (f) recording said determining C 2 value; (g) repeating steps (a) through (f) at successive times to accumulate a plurality of recorded C 2 values over a period of time; (h) comparing the first of said accumulated C 2 values against a predetermined diagnostic threshold value discriminating between C 2 values associated with a healthy condition; (i) identifying an improving congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending toward said threshold value; (j) identifying an improving healthy trend away from a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending away from said threshold value; (k) identifying a deteriorating congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending away from said threshold value; and (1) identifying a trend toward a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending toward said threshold value.

Claim 15

A method of diagnosing congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure over time to obtain a representation of one or more pressure waves each corresponding to a beat of the human heart; (c) determining the mean arterial pressure; (d) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves and from said mean arterial pressure and cardiac output value; and (e) testing said C 2 value against a predetermined diagnostic threshold value below which C 2 values are associated with a congestive heart failure condition whereby a CHF condition may be identified.

Claim 16

A method of diagnosing congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure over time to obtain a representation of one or more pressure waves each corresponding to a beat of the human heart; (c) determining the mean arterial pressure; (d) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves and from said mean arterial pressure and cardiac output value; and (e) testing said C 2 value against a predetermined diagnostic threshold value below which C 2 values are associated with a congestive heart failure condition whereby a CHF condition may be identified.

Claim 17

A method for monitoring congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure over time to obtain a representation of one or more pressure waves each corresponding to a beat of the human heart; (c) determining the mean arterial pressure; (d) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves and from said mean arterial pressure and cardiac output value; (e) recording said determined C 2 value; (f) repeating steps (a) through (e) at successive times to accumulate a plurality of recorded C 2 values over a period of time; (g) comparing the first of said accumulated C 2 values against a predetermined diagnostic threshold value discriminating between C 2 values associated with a congestive heart failure condition and those C 2 values associated with a healthy condition; (h) identifying an improving congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending toward said threshold value; and (i) identifying an improving healthy trend away from a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending away from said threshold value; (j) identifying a deteriorating congestive heart failure condition when said first C 2 values is below said threshold value and the remaining C 2 values are trending away from said threshold value; and (k) identifying a trend toward a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending toward said threshold value.

Claim 18

A method for monitoring congestive heart failure, comprising the steps of: (a) obtaining a cardiac output value; (b) measuring arterial pressure over time to obtain a representation of one or more pressure waves each corresponding to a beat of the human heart; (c) determining the mean arterial pressure; (d) determining the value of the parameter C 2 of the modified Windkessel model from the pulse contour of the diastolic portion of said one or more waves and from said mean arterial pressure and cardiac output value; (e) recording said determined C 2 value; (f) repeating steps (a) through (e) at successive times to accumulate a plurality of recorded C 2 values over a period of time; (g) comparing the first of said accumulated C 2 values against a predetermined diagnostic threshold value discriminating between C 2 values associated with a congestive heart failure condition and those C 2 values associated with a healthy condition; (h) identifying an improving congestive heart failure condition when said first C 2 value is below said threshold value and the remaining C 2 values are trending toward said threshold value; and (i) identifying an improving healthy trend away from a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending away from said threshold value; (j) identifying a deteriorating congestive heart failure condition when said first C 2 values is below said threshold value and the remaining C 2 values are trending away from said threshold value; and (k) identifying a trend toward a congestive heart failure condition when said first C 2 value is above said threshold value and the remaining C 2 values are trending toward said threshold value.