WO2005102451A1 - Detection of diastolic heart failure - Google Patents

Detection of diastolic heart failure Download PDF

Info

Publication number
WO2005102451A1
WO2005102451A1 PCT/SE2004/000636 SE2004000636W WO2005102451A1 WO 2005102451 A1 WO2005102451 A1 WO 2005102451A1 SE 2004000636 W SE2004000636 W SE 2004000636W WO 2005102451 A1 WO2005102451 A1 WO 2005102451A1
Authority
WO
WIPO (PCT)
Prior art keywords
patient
pressure
characterized
pulse
dhf
Prior art date
Application number
PCT/SE2004/000636
Other languages
French (fr)
Inventor
Sven-Erik Hedberg
Anders Björling
Maria Torpo
Karin Ljungström
Original Assignee
St Jude Medical Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by St Jude Medical Ab filed Critical St Jude Medical Ab
Priority to PCT/SE2004/000636 priority Critical patent/WO2005102451A1/en
Publication of WO2005102451A1 publication Critical patent/WO2005102451A1/en

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/02Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
    • A61B5/021Measuring pressure in heart or blood vessels
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/18Applying electric currents by contact electrodes
    • A61N1/32Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/362Heart stimulators
    • A61N1/3627Heart stimulators for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/18Applying electric currents by contact electrodes
    • A61N1/32Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/362Heart stimulators
    • A61N1/37Monitoring; Protecting
    • A61N1/3702Physiological parameters
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/02Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
    • A61B5/021Measuring pressure in heart or blood vessels
    • A61B5/0215Measuring pressure in heart or blood vessels by means inserted into the body
    • A61B5/02154Measuring pressure in heart or blood vessels by means inserted into the body by optical transmission
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61NELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00Electrotherapy; Circuits therefor
    • A61N1/18Applying electric currents by contact electrodes
    • A61N1/32Applying electric currents by contact electrodes alternating or intermittent currents
    • A61N1/36Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
    • A61N1/362Heart stimulators
    • A61N1/365Heart stimulators controlled by a physiological parameter, e.g. heart potential
    • A61N1/36514Heart stimulators controlled by a physiological parameter, e.g. heart potential controlled by a physiological quantity other than heart potential, e.g. blood pressure
    • A61N1/36564Heart stimulators controlled by a physiological parameter, e.g. heart potential controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by blood pressure

Abstract

An implantable medical apparatus for detecting diastolic heart failure, DHF, comprises a DHF determining device for determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient. The DHF determining device comprises a pressure measuring means (2,10,12,16) for measuring pulse pressure in a cardiac cycle for a predetermined workload situation of the patient as said blood pressure parameter, and a comparison means (14) compares the measured pulse pressure with a predetermined reference value. A pacemaker comprises such an apparatus and control means (20) for optimising pacing therapy depending on the result of the comparison of the measured pulse pressures with said predetermined reference values. A corresponding method of detecting diastolic heart failure, DHF, comprises the step of determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient. This step of determining at least one blood parameter comprises determining, as said blood pressure parameter, the pulse pressure in a cardiac cycle for a predetermined workload situation of the patient, and the determined pulse pressure is compared with a predetermined reference value.

Description

DETECTION OF DIASTOLIC HEART FAILURE

Technical Field The present invention relates to an implantable medical apparatus for detecting diastolic heart failure, DHF, comprising a DHF determining device for determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient. The invention also relates to a pacemaker provided with such an apparatus, and a method of detecting DHF, comprising the step of determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient.

Background There is a growing recognition that congestive heart failure caused by a predominant abnormality in the diastolic function, i.e. diastolic heart failure, DHF, is both common and causes significant morbidity and mortality. Therefore early detection of DHF is important. Patients do not, however, seem to have symptoms at an early stage. In addition it has been hard to separate diastolic and systolic heart failure and they may also exist simultaneously. It has been discovered that among the few parameters, separating diastolic heart failure from systolic heart failure, are certain blood pressure parameters obtained during work of the patient. Thus US 6 438 408 describes an implantable medical device for monitoring congestive heart failure, CHF. A plurality of heart failure parameters indicative of the state of the heart failure are measured employing EGMs, blood pressures including absolute pressures, developed pressures (= systolic pressures - diastolic pressures) and the time derivative dP/dt, as well as heart chamber volumes. One of these parameters is the relaxation or contraction time constant τ of the heart chamber, τ is calculated from a continuous pressure signal and is the drop in ventricular pressure at the end of systole and in the first part of diastole. The τ parameter is thus a general parameter reflecting the relaxation process. According to an article by Dalane W. Kitzman et al., Pathophysiological Characterization of Isolated Diastolic Heart Failure in Comparison to Systolic Heart Failure, JAMA vol. 288, No. 17, 2144, November 6, 2002 the exercise pulse pressure is one parameter separating systolic heart failure from diastolic heart failure. The purpose of the present invention is to utilize this knowledge to propose a technique for detecting DHF, preferably at an early stage when the patient still does not seem to have any symptoms, based on measurement of pulse pressure under work.

Disclosure of the Invention This purpose is obtained by an apparatus, a pacemaker and a method of the kind mentioned in the introductory portion of the description and having the characterizing features of claims 1 , 10 and 13 respectively. Thus with the present invention the reduced peak and submaximal exercise performance of DHF patients is utilized for detecting DHF. With the technique according to the invention it is possible to detect DHF at an early stage, often before the patient seem to have any symptoms. In the present invention the workload situation of the patient must be identified, and therefore, according to an advantageous embodiment of the apparatus according to the invention, an activity sensor is provided for determining the workload of the patient. According to another advantageous embodiment of the apparatus according to the invention an averaging means is provided to form an average value of pulse pressures during a plurality of cardiac cycles with said workload situation and an average value of pulse pressures measured during a plurality of cardiac cycles with the patient in rest. In this way the quality of the pulse pressure measurements is improved. According to other advantageous embodiments of the apparatus according to the invention a wireless communication means is connected to said comparison means for automatically sending the results of the comparison of measured pulse pressures with said reference values to external receiver means, or a storing means is provided for storing the results of the comparison of measured pulse pressures with said reference values. Thus if the pulse pressure has risen above the reference value in a predetermined way this condition is automatically transmitted to a physician or stored for transmission in connection with a follow-up. According to still other advantageous embodiments of the apparatus according to the invention said pressure measuring means comprise a pressure sensor adapted for placement in right ventricle or coronary veins of the patient's heart, and said pressure measuring means are adapted to determine maximum and minimum pressures in a cardiac cycle. It is preferred to place the pressure sensor in the right ventricle or the coronary veins, since the pressures in these places reflect the morphology of the left ventricular or aortic pulse pressure, especially with regard to maximum and minimum pressures. The invention also relates to a pacemaker provided with the apparatus for detecting DHF and control means for optimising pacing therapy depending on the result of the comparison of said measured pulse pressures with said predetermined reference values. The pressure measuring means of the apparatus according to the invention then preferably comprises a pressure sensor connected to the pacemaker, since it can monitor the pulse pressure of its carrier for long periods. This is an advantage since evolvement of DHF is a slow process. An advantageous embodiment of the pacemaker according to the invention comprises a rate responsive sensor for use as activity sensor for determining the workload situation of the patient. Even the pressure sensor of the pacemaker can be used as activity sensor. According to an advantageous embodiment of the method according to the invention photo-plethysmographic signals are sensed for determining the pulse pressure, since it has been discovered that photo-plethysmographic signals obtained by a sensor placed close to the tissue where a pacemaker or ICD is implanted contain information about pulse pressure. As mentioned above the measured pulse pressure is compared with a predetermined reference value, and according to an advantageous embodiment of the apparatus and the method according to the invention said pulse pressure in a cardiac cycle is measured for a predetermined workload situation and a rest situation of the patient, and the difference between said pulse pressures measured in said workload and rest situations is compared with a predetermined reference value for said difference for DHF detection. A condition of DHF is identified by a higher pulse pressure during workload than a patient with a systolic heart failure would have. The reference value for detection of DHF is preferably obtained from measurements on the patient at an early stage of the implantation period of the apparatus or pacemaker. The patient is supposed not to suffer from DHF at the time of implantation. Therefore, according to an advantageous embodiment of the method according to the invention, pulse pressures are measured for different workloads of the patient and for the patient in rest at an early time, when the patient is not suffering from DHF, for determining said reference values. These pulse pressures from an early stage can also be measured for a certain period of time and typical pulse pressures during an identified workload and during rest are gathered and averaged and then stored for later use as reference values for comparison purposes. If later the measured pulse pressure, or average pulse pressure measured during several cardiac cycles, exceeds the reference value determined in this way by a prescribed amount x%, this is used as an indication of DHF.

Brief Description of the Drawings To explain the invention in greater detail an embodiment of the invention will now be described with reference to the drawings on which figurel is a diagram showing the left ventricular and aortic pressures as a function of time, figure 2 shows a block diagram of an embodiment of a pacemaker according to the invention, figure 3 is a flow chart illustrating the overall collection of pulse pressure data in an embodiment of the apparatus according to the invention, and figure 4 is a flow chart explaining in greater detail an example of the procedure for obtaining pulse pressure data according to the present invention.

Description of a Preferred Embodiment In the following an embodiment of the invention using a pressure sensor will be described, and by the expression pulse pressure is meant the varying pressure in aorta during a cardiac cycle. The above-mentioned pulse pressure can be obtained from the pressure measured in the left ventricle. In figure 1 the top curve shows the left ventricular pressure and the curve below the aortic pressure as a function of time. The magnitude of the pressures are indicated in arbitrary units in the figure. The asterisks in the curves of figure 1 denote time points for the maxima and minima of the time derivative of the left ventricular pressure, dLVP/dtmax and dLVP/dtmin respectively. As the aortic valves open close to the point dLVP/dtmax , the aortic pressure is close to the left ventricular pressure at this point of time. During the period from dLVP/dtmaxto dLVP/dtmin blood flows into aorta. The maximum of aortic pressure is situated in this period. The pulse pressure can consequently be obtained from left ventricular pressure by subtracting the pressure at the point of dLVP/dtmaxfrom the maximum of the left ventricular pressure obtained during the mentioned period. If the conditions are such that pressure signals from other parts of the hemodynamic system are morphologically similar to the left ventricular pressure, these signals can also be used for determining the pulse pressure in the present invention, since only relative changes have to be determined for detecting DHF. Figure 2 shows an embodiment of a pacemaker according to the invention comprising basic pacemaker circuits 20. A pressure sensor 2 is located in the right ventricle 18 of a patient's heart and connected to the pacemaker 4. The signals from the pressure sensor 2 are supplied to an A/D-converter 10. After A/D- conversion the time derivative of the signal is formed in a derivation unit 16. The time derivative of the pressure signals are filtered in the low pass filter 12 before supply to the microprocessor and supporting circuits 14. Since time derivation promotes high frequency noise, it is advisable to eliminate in this way possible false peaks and valleys, which could be interpreted as dLVP/dtmaxand dLVP/dtmin- The filtered signals are supplied regularly into microprocessor and supporting circuits 14. Located in the pacemaker 4 is an activity sensor 6 which is connected to an activity measuring unit 8 for determining the workload of the patient. A corresponding activity or workload signal is fed to the microprocessor and supporting circuits 14. Figure 3 is a flow chart illustrating an example of the overall process for collecting pulse pressure data. The development of DHF is a slow process as mentioned. A timer, at 26 in figure 3, is therefore provided for activating pulse pressure measurements on a regular basis for reducing the current drain and releasing microprocessor power. Collection of pulse pressure data is performed for different workloads of the patient, at 22 in figure 3. As mentioned above the collection process is activated by a timer, at 26, and therefore the process has to wait for activation by the timer before starting, at 24. As the process is started, at 28, pulse pressure data are stored in different intermediate memory locations depending on the workload of the patient, at 30. Addresses to this memory locations are obtained from a table pointed to by the workload or activity measuring unit depending on the workload or activity,, at 32. Pulse pressure data from the intermediate memory is then stored in another memory according to the address obtained in the preceding step for later analysis, at 34 . To improve the accuracy of the data stored the procedure of storing pulse pressure data can be performed by forming a floating mean value. One way to do this is to add a fraction 1/k of a new pulse pressure value P(i) to the pulse pressure value stored Pstorea at the memory location pointed to by the activity measuring unit and form a mean value Pst0re according to the following equation

P(i) + Pstore X (k - 1 ) r store = k

Figure 4 is a flow chart illustrating in greater detail the procedure for obtaining the pulse pressure. Pmax and Pmin denote temporary storages of maximum and minimum aortic pressures. In order to start the pulse pressure measurements a QRS has to be detected , at 38 in figure 4, after reset of Pmax and Pmjn , at 36. Pressure samples P(i) are then stored continuously together with the time derivative dP(i)/dt for comparison, at 40. A certain number of contiguous samples have to exist simultaneously, so that the above-mentioned filtering of the time derivative of the pressure is in accordance with the length of the filter coefficients. Care must be taken so that the delay in the filter influences the selection of corresponding pressure samples in a timely fashion, i.e. the pressure samples are picked with the same delay. When dP/dtmax has been found, at 42 and 44, the pressure at that point in time is selected as the minimum pressure Pmin. The pressure then rises in the aorta and the maximum pressure during systole occurs in the period between dP/dtmaxand dP/dtmin, cf. the description of figure 1. In the process illustrated in figure 4 a simplified approach is used for determining maximum pressure Pmax. Instead of determing the point of time for dP/dtmιn a timer is started at the point of dP/dtmaχ. at 46 in figure 4 and Pmax is determined according to steps 48, 50, 52, 54 till timer overflow, at 56. Such a timer procedure is justified since the systolic time period in practice varies little. The pulse pressure is then obtained by subtracting Pmin from Pmax, at 58, which is the output of the process.

Instead of determining the pulse pressure with the aid of pressure sensors it can be determined by photo-plethysmography. Photo-plethysmographic signals from a sensor placed close to the tissue at the location of the implanted pacemaker or ICD contains information on pulse pressure. Thus such photo-pletysmographic signals can be used as an alternative for determining the pulse pressure.

Claims

1. An implantable medical apparatus for detecting diastolic heart failure, DHF, comprising a DHF determining device for determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient, characterized In that said DHF determining device comprises a pressure measuring means (2,10,12,16) for measuring pulse pressure in a cardiac cycle for a predetermined workload situation of the patient as said blood pressure parameter, and a comparison means (14) for comparing the measured pulse pressure with a predetermined reference value.
2. The apparatus according to claim 1 , characterized in that said pressure measuring means (2,10,12,16) are adapted to measure the pulse pressure in a cardiac cycle for a predetermined workload situation and a rest situation of the patient, and in that said comparison means (14) is adapted to compare the difference between said pulse pressures measured in said workload and rest situations with a predetermined reference value for said difference for DHF detection.
3. The apparatus according to claims 1 or 2, characterized in that an activity sensor (6) is provided for determining the workload of the patient.
4. The apparatus according to any of the preceding claims, characterized in that an averaging means (14) is provided to form an average value of pulse pressures during a plurality of cardiac cycles with said predetermined workload situation and an average value of pulse pressures measured during a plurality of cardiac cycles with the patient in rest.
5. The apparatus according to any of the preceding claims, characterized in that a wireless communication means is connected to said comparison means (14) for automatically sending the results of the comparison of measured pulse pressures with said reference values to external receiver means.
6. The apparatus according to any of the claims 1 - 4, characterized in that a storing means (14) is provided for storing the results of the comparison of measured pulse pressures with said reference values.
7. The apparatus according to any of the preceding claims, characterized in that said pressure measuring means comprise a pressure sensor (2) adapted for placement in right ventricle (18) or coronary veins of the patient's heart.
8. The apparatus according to any of the preceding claims, characterized in that said pressure measuring means (2,10,12,16) are adapted to determine maximum and minimum pressures in a cardiac cycle.
9. The apparatus according to claim 1 , characterized in that said pressure measuring means comprise a sensor for delivering photo-plethysmographic signals to be used for determing the pulse pressure.
10. A pacemaker, characterized in that it comprises an apparatus according to any one of the preceding claims and control means (20) for optimising pacing therapy depending on the result of the comparison of said measured pulse pressures with said predetermined reference values.
11. The pacemaker according to claim 10, characterized in that it comprises a rate responsive sensor (6) for determining the workload situation of the patient.
12. The pacemaker according to claim 10 comprising a pressure sensor, characterized in that said pressure sensor (2) is arranged as said activity sensor.
13. A method of detecting diastolic heart failure, DHF, comprising the step of determining at least one blood pressure parameter for detecting a DHF state of the heart of a patient, characterized in that said step of determining at least one blood pressure parameter comprises determining, as said blood pressure parameter, the pulse pressure in a cardiac cycle for a predetermined workload situation of the patient, and in that the determined pulse pressure is compared with a predetermined reference value.
14. The method according to claim 13, characterized in that said pulse pressure in a cardiac cycle is measured for a predetermined workload situation and a rest situation of the patient, and the difference between said pulse pressures measured in said workload and rest situations is compared with a predetermined reference value for said difference for DHF detection.
15. The method according to claims 13 or 14, characterized in that an average value of pulse pressures is measured during a plurality of cardiac cycles with said predetermined workload situation and an average value of pulse pressures is measured during a plurality of cardiac cycles with the patient in rest.
16. The method according to any of the claims 13 - 15, characterized in that the results of the comparison of measured pulse pressures with said reference values are automatically sent to external receiver means.
17. The method according to any of the claims 13 -16, characterized in that the pulse pressure is measured in right ventricle or coronary veins of the patient's heart.
18. The method according to any of the claims 13 - 17, characterized in that maximum and minimum pressures are determined in a cardiac cycle.
19. The method according to claim 13, characterized in that photo- plethysmographic signals are sensed for determining the pulse pressure.
20. The method according to any of the claims 13 - 19, characterized in that pulse pressures are measured for different workloads of the patient and for the patient in rest at an early time, when the patient is not suffering from DHF for determining said reference values.
PCT/SE2004/000636 2004-04-26 2004-04-26 Detection of diastolic heart failure WO2005102451A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/SE2004/000636 WO2005102451A1 (en) 2004-04-26 2004-04-26 Detection of diastolic heart failure

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US10/562,109 US7483742B2 (en) 2004-04-26 2004-04-26 Detection of diastolic heart failure
EP04729568A EP1740266B1 (en) 2004-04-26 2004-04-26 Detection of diastolic heart failure
DE602004020120T DE602004020120D1 (en) 2004-04-26 2004-04-26 Detecting diastolic heart failure
PCT/SE2004/000636 WO2005102451A1 (en) 2004-04-26 2004-04-26 Detection of diastolic heart failure

Publications (1)

Publication Number Publication Date
WO2005102451A1 true WO2005102451A1 (en) 2005-11-03

Family

ID=35196753

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2004/000636 WO2005102451A1 (en) 2004-04-26 2004-04-26 Detection of diastolic heart failure

Country Status (4)

Country Link
US (1) US7483742B2 (en)
EP (1) EP1740266B1 (en)
DE (1) DE602004020120D1 (en)
WO (1) WO2005102451A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008026970A1 (en) 2006-08-28 2008-03-06 St. Jude Medical Ab Determining the variation over the time of a medical parameter of a human being

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7658196B2 (en) 2005-02-24 2010-02-09 Ethicon Endo-Surgery, Inc. System and method for determining implanted device orientation
US7775966B2 (en) 2005-02-24 2010-08-17 Ethicon Endo-Surgery, Inc. Non-invasive pressure measurement in a fluid adjustable restrictive device
US7927270B2 (en) 2005-02-24 2011-04-19 Ethicon Endo-Surgery, Inc. External mechanical pressure sensor for gastric band pressure measurements
US8066629B2 (en) 2005-02-24 2011-11-29 Ethicon Endo-Surgery, Inc. Apparatus for adjustment and sensing of gastric band pressure
US8016744B2 (en) 2005-02-24 2011-09-13 Ethicon Endo-Surgery, Inc. External pressure-based gastric band adjustment system and method
US8152710B2 (en) 2006-04-06 2012-04-10 Ethicon Endo-Surgery, Inc. Physiological parameter analysis for an implantable restriction device and a data logger
US8870742B2 (en) 2006-04-06 2014-10-28 Ethicon Endo-Surgery, Inc. GUI for an implantable restriction device and a data logger
US7699770B2 (en) 2005-02-24 2010-04-20 Ethicon Endo-Surgery, Inc. Device for non-invasive measurement of fluid pressure in an adjustable restriction device
US7775215B2 (en) 2005-02-24 2010-08-17 Ethicon Endo-Surgery, Inc. System and method for determining implanted device positioning and obtaining pressure data
US7946995B1 (en) * 2006-11-09 2011-05-24 Pacesetter, Inc. Analyzing circadian variations of a hemodynamic parameter to determine an adverse cardiac condition
US8187163B2 (en) 2007-12-10 2012-05-29 Ethicon Endo-Surgery, Inc. Methods for implanting a gastric restriction device
US8100870B2 (en) 2007-12-14 2012-01-24 Ethicon Endo-Surgery, Inc. Adjustable height gastric restriction devices and methods
US8377079B2 (en) 2007-12-27 2013-02-19 Ethicon Endo-Surgery, Inc. Constant force mechanisms for regulating restriction devices
US8142452B2 (en) 2007-12-27 2012-03-27 Ethicon Endo-Surgery, Inc. Controlling pressure in adjustable restriction devices
US8192350B2 (en) 2008-01-28 2012-06-05 Ethicon Endo-Surgery, Inc. Methods and devices for measuring impedance in a gastric restriction system
US8337389B2 (en) 2008-01-28 2012-12-25 Ethicon Endo-Surgery, Inc. Methods and devices for diagnosing performance of a gastric restriction system
US8591395B2 (en) 2008-01-28 2013-11-26 Ethicon Endo-Surgery, Inc. Gastric restriction device data handling devices and methods
US8221439B2 (en) 2008-02-07 2012-07-17 Ethicon Endo-Surgery, Inc. Powering implantable restriction systems using kinetic motion
US7844342B2 (en) 2008-02-07 2010-11-30 Ethicon Endo-Surgery, Inc. Powering implantable restriction systems using light
US8114345B2 (en) 2008-02-08 2012-02-14 Ethicon Endo-Surgery, Inc. System and method of sterilizing an implantable medical device
US8591532B2 (en) 2008-02-12 2013-11-26 Ethicon Endo-Sugery, Inc. Automatically adjusting band system
US8057492B2 (en) 2008-02-12 2011-11-15 Ethicon Endo-Surgery, Inc. Automatically adjusting band system with MEMS pump
US8034065B2 (en) 2008-02-26 2011-10-11 Ethicon Endo-Surgery, Inc. Controlling pressure in adjustable restriction devices
US8233995B2 (en) 2008-03-06 2012-07-31 Ethicon Endo-Surgery, Inc. System and method of aligning an implantable antenna
US8187162B2 (en) 2008-03-06 2012-05-29 Ethicon Endo-Surgery, Inc. Reorientation port
US20100234906A1 (en) * 2009-03-16 2010-09-16 Pacesetter, Inc. System and method for controlling rate-adaptive pacing based on a cardiac force-frequency relation detected by an implantable medical device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0591642A1 (en) * 1992-10-07 1994-04-13 Pacesetter AB Rate-responsive heart stimulator
US5476483A (en) * 1994-06-10 1995-12-19 Pacesetter, Inc. System and method for modulating the base rate during sleep for a rate-responsive cardiac pacemaker
US6438408B1 (en) * 2000-12-28 2002-08-20 Medtronic, Inc. Implantable medical device for monitoring congestive heart failure
US20030204145A1 (en) * 2002-04-30 2003-10-30 Jan Manolas Device for and method of rapid noninvasive measurement of parameters of diastolic function of left ventricle and automated evaluation of the measured profile of left ventricular function at rest and with exercise

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6876881B2 (en) * 2002-08-16 2005-04-05 Cardiac Pacemakers, Inc. Cardiac rhythm management system with respiration synchronous optimization of cardiac performance using atrial cycle length
US7363077B1 (en) * 2004-11-09 2008-04-22 Pacesetters, Inc. Adaptive timing interval control method for treating congestive heart failure

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0591642A1 (en) * 1992-10-07 1994-04-13 Pacesetter AB Rate-responsive heart stimulator
US5476483A (en) * 1994-06-10 1995-12-19 Pacesetter, Inc. System and method for modulating the base rate during sleep for a rate-responsive cardiac pacemaker
US6438408B1 (en) * 2000-12-28 2002-08-20 Medtronic, Inc. Implantable medical device for monitoring congestive heart failure
US20030204145A1 (en) * 2002-04-30 2003-10-30 Jan Manolas Device for and method of rapid noninvasive measurement of parameters of diastolic function of left ventricle and automated evaluation of the measured profile of left ventricular function at rest and with exercise

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
MANDINOV L. ET AL.: "Diastolic heart failure", CARDIOVASCULAR RESEARCH, vol. 45, 2000, pages 813 - 825, XP002903833 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008026970A1 (en) 2006-08-28 2008-03-06 St. Jude Medical Ab Determining the variation over the time of a medical parameter of a human being

Also Published As

Publication number Publication date
DE602004020120D1 (en) 2009-04-30
EP1740266B1 (en) 2009-03-18
US20060149327A1 (en) 2006-07-06
US7483742B2 (en) 2009-01-27
EP1740266A1 (en) 2007-01-10

Similar Documents

Publication Publication Date Title
US7158830B2 (en) Method and apparatus for optimizing stroke volume during DDD resynchronization therapy using adjustable atrio-ventricular delays
EP1536859B1 (en) System for detection and treatment of myocardial wall stress
US9119908B2 (en) Synchronization control system
US7383086B2 (en) Ventricular conduction delay trending system and method
US8032214B2 (en) Method and apparatus for optimizing ventricular synchrony during DDD resynchronization therapy using adjustable atrio-ventricular delays
EP1680179B1 (en) Pacing system for diastolic dysfunction
JP4122217B2 (en) Apparatus and method for controlling a balloon pump in the aorta
EP1049403B1 (en) Long term monitoring of acceleration signals for optimization of pacing therapy
EP1687062B1 (en) Method and apparatus for controlling extra-systolic stimulation (ess) therapy using ischemia detection
US7181268B2 (en) Ischemia detection
EP0365614B1 (en) Cardiovascular pressure and condition method and apparatus
EP1045718B1 (en) Heart stimulator determining cardiac output, by measuring the systolic pressure, for controlling the stimulation
EP0902708B1 (en) Apparatus for optimizing pacemaker av delay
US8827919B2 (en) Method and apparatus for third heart sound detection
US20040078059A1 (en) Cardiac pacing using adjustable atrio-ventricular delays
US20060247702A1 (en) Measurement of coronary sinus parameters to optimize left ventricular performance
US7130681B2 (en) Use of accelerometer signal to augment ventricular arrhythmia detection
EP1195133A2 (en) Oscillometric blood pressure monitor with improved perfomance in the presence of arrhythmias
US20140046200A1 (en) Monitoring of heart sounds
US6314322B1 (en) System and method for treating dilated cardiomyopathy using end diastolic volume (EDV) sensing
EP1960043B1 (en) Using implanted sensors for feedback control of implanted medical devices
JP4861323B2 (en) Techniques for blood pressure measurement with implantable devices
US6945939B2 (en) Hemodynamic analysis
US20030199937A1 (en) Atrial interval based heart rate variability diagnostic for cardiac rhythm management system
EP1911399B1 (en) Techniques for correlating thoracic impedance with physiological status

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 2004729568

Country of ref document: EP

AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

ENP Entry into the national phase in:

Ref document number: 2006149327

Country of ref document: US

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 10562109

Country of ref document: US

DPEN Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed from 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWP Wipo information: published in national office

Ref document number: 10562109

Country of ref document: US

WWW Wipo information: withdrawn in national office

Country of ref document: DE

NENP Non-entry into the national phase in:

Ref country code: DE

WWP Wipo information: published in national office

Ref document number: 2004729568

Country of ref document: EP