Method and system to correct contractility based on non-heart failure factors

摘要

A method for trending heart failure measures cardiogenic impedance (CI) and obtains signals representing estimates for or direct measurements of at least one of cardiac volume and pressure of the heart when the CI measurements were obtained. The method identifies correction factors based on the signals and applies the correction factors to the contractility estimates. A system for trending heart failure includes a contractility module to determine contractility estimates from CI measurements taken along at least a first vector through a heart, and a collection module to receive signals representing estimates for or direct measurements of at least one of cardiac volume and pressure of the heart when the CI measurements were obtained. The system further includes a factor module to identify correction factors based on the signals and a correction module to apply the correction factors to the contractility estimates.

主权项

1. A method for trending heart failure (HF) based on heart contractility information, comprising:
measuring cardiogenic impedance (CI) measurements along at least a first vector through a heart over a period of time; determining contractility estimates from the CI measurements, the contractility estimates relating to contractility of the heart; obtaining contractility factors representing estimates for or direct measurements of at least one of cardiac volume and pressure of the heart when the CI measurements were obtained; identifying correction factors based on the contractility factors; applying the correction factors to the contractility estimates to produce contractility trend values over the period of time; and applying therapy to the heart to optimize contractility of the heart as a function of the trend values.