Digital electrode for cardiac rhythm management

Abstract

A cardiac rhythm management apparatus includes a proximal housing, a distal housing and a lead. The proximal housing includes a first energy storage device. The distal module is implantable within a patient's heart, and includes a second energy storage device, at least one electrode, and a control module. The control module controls the delivery of at least one electrical stimulus from the second energy storage device to a location in communication with the patient's heart. The lead connects the proximal housing to the distal module and is configured to communicate one or more digital signals between the proximal housing and the distal module.

Description

[0001] This application claims priority from U.S. Provisional No. 60 / 531,238 filed Dec. 19, 2003, which is incorporated by reference herein.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates generally to systems and methods for detecting, diagnosing and treating cardiovascular disease in a medical patient using cardiac rhythm management devices and methods that use novel digital electrode technology. [0004] 2. Description of the Related Art [0005] The optimum management of patients with chronic diseases requires that therapy be adjusted in response to changes in the patient's condition. Ideally, these changes are measured by daily patient self-monitoring prior to the development of symptoms. Self-monitoring and self-administration of therapy forms a closed therapeutic loop, creating a dynamic management system for maintaining homeostasis. Such a system can, in the short term, benefit day-to-day symptoms and quality-of-life, and in the long ter...

AI Technical Summary

Benefits of technology

The present invention relates to systems and methods for detecting, diagnosing, and treating cardiovascular disease in a medical patient using cardiac rhythm management devices. The invention provides several embodiments that minimize the number of electrical conductors required in the lead, which improves lead reliability and reduces the risk of lead unreliability, sensing errors, and pacing failures. The invention also reduces the complexity of the connector that plugs into the pacemaker generator housing, and minimizes the potential for RF noise and induced voltages. Overall, the invention provides a more efficient and reliable approach to cardiac rhythm management.

Problems solved by technology

Although sharing of electrodes for pacing and sensing is common, it does have limitations.

Moreover, following each pacing pulse there is a time interval during which sensing cannot take place because the relatively high pacing pulse voltage persists for some time due to capacitance in the lead.

Thus, potentially important electrophysiological data may be lost during this interval with presently available pacemaker technology.

However, in some cases, such a lead would conventionally require separate sensing and pacing conductors as well, which would disadvantageously require the lead diameter to be increased.

One disadvantage with such multiple function pacemaker leads is the that increased number of electrical conductors required within the lead forces the lead to be larger in diameter and less flexible, or that the conductors become smaller.

Smaller conductors in pacemaker leads may break more often over time, resulting in lower lead reliability.

Smaller conductors have higher electrical resistance, resulting in an undesirable voltage drop between the generator and the pacing electrode(s).

An increased number of conductors also increases the complexity of the connector that plugs into the pacemaker generator housing.

As such, the sensing signals in particular are subject to noise due to muscular activity, radiofrequency (RF) interference, and potential cross-talk between physiological and electrical sensing signals.

RF noise on the sense conductor may cause erroneous pacing, even with sophisticated digital filtering algorithms commonly used in pacemaker sensing systems.

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