Implantable medical device for monitoring congestive heart failure
US6438408B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2000 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Dec 28, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/36564
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An implantable stimulator and monitor measures a group of heart failure parameters indicative of the state of heart failure employing EGM signals, measures of blood pressure including absolute pressure P, developed pressure (DP=systolic P−diastolic P), and/or dP/dt, and measures of heart chamber volume (V) over one or more cardiac cycles. These parameters include: (1) relaxation or contraction time constant tau (&tgr;); (2) mechanical restitution (MR), i.e., the mechanical response of a heart chamber to premature stimuli applied to the heart chamber; (3) recirculation fraction (RF), i.e., the rate of decay of PESP effects over a series of heart cycles; and (4) end systolic elastance (EES), i.e., the ratios of end systolic blood pressure P to volume V. These heart failure parameters are determined periodically regardless of patient posture and activity level. However, certain of the parameters are only measured or certain of the data are only stored when the patient heart rate is regular and within a normal sinus range between programmed lower and upper heart rates. The parameter data is associated with a date and time stamp and with other patient data, e.g., patient activity …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.