Surgery – Diagnostic testing – Cardiovascular
Reexamination Certificate
2000-07-06
2003-06-24
Jastrzab, Jeffrey R. (Department: 3762)
Surgery
Diagnostic testing
Cardiovascular
Reexamination Certificate
active
06584343
ABSTRACT:
BACKGROUND OF THE INVENTION
I. Field of the Invention
The present invention generally relates to devices, systems, and methods for diagnosing and/or treating the heart. In particular, the invention provides methods and systems for sensing heart signals, and especially for localizing and/or treating arrhythmias.
Significant progress has recently been made toward effective treatments of many cardiac arrhythmias. Contraction of a healthy human heart generally propagates through the heart tissue from the sinus node in the right atrium, and eventually the associated ventricles. This normal propagation of contraction forces blood to flow from the atria to the ventricles in a synchronized pumping action. Arrhythmias of the heart often originate at and/or propagate from alternative heart tissues, resulting in rapid irregular or regular contractions of some or all of the heart. Radiofrequency (RF) intracardiac catheter ablation of the alternative ectopic origin, an abnormal conduction pathway, or an abnormal pathway exit site is now used to effectively treat a variety of arrhythmias.
Although quite effective, current catheter ablation for treatment of cardiac arrhythmias has significant disadvantages. A particular challenge in an effective catheter ablation treatment is the time required for proper identification of the treatment site. Careful mapping of the arrhythmia via multiple catheters is generally required to accurately define the treatment site and limit the size of the ablation. Unfortunately, reliably and repeatedly inducing an arrhythmia can be quite difficult, and can result in a lengthy and unpredictable procedure. As an alternative, candidate ablation sites may be tested during normal sinus rhythm by pace mapping. This testing may be quite time-consuming, as it often involves pacing at several sites with an artificial arrhythmia being initiated using a small electrical pulse from a catheter at each site. The candidate sites are often tested sequentially by positioning the intracardiac catheter against a candidate site within (for example) the right ventricle, identifying the engaged tissue location within the ventricle, sensing and/or pacing the heart cycles at the candidate site, repositioning the intracardiac catheter to a new candidate site, and repeating this process until an ectopic origin or an abnormal pathway exit site has been identified.
As fluoroscopy is often used to identify the location of the engaged tissue, this sequential iterative process can result in significant exposure of the patient and treating personnel to potentially harmful radiation. While alternative (and more complex) intracardiac catheter probe structures have been proposed to allow more rapid identification of the ectopic origin(s) or abnormal pathway exit sites of ventricular tachycardias (VTs) and other arrhythmias, the size and cost of these complex structures may limit their acceptability.
To overcome the disadvantages associated with the known, time consuming and/or invasive intracardiac arrhythmia sensing and localization techniques, researchers have been working on alternative arrhythmia localization techniques which rely on body surfacing mapping, often during pacing. Electrocardiograms (ECGs) may be recorded during abnormal atrial or ventricular activity and compared with ECGs taken during pacing at different sites within the heart to help identify the ectopic site, with the ECGs optionally taken using a standard 12-lead ECG system. More detailed information regarding ectopic sites can be obtained by recording heart cycle signals at the body surface using a more comprehensive sensor array (sometimes called body surface ECG mapping or body surface potential mapping). These heart signals, which generally comprise small amplitude variations in electrical potential along the anterior and/or posterior torso, can be manipulated and/or mapped so as to provide an indication of the origin of the arrhythmia within the heart. Much of this work has concentrated on VT. More recent work has begun to investigate the possibility of localizing certain atrial arrhythmias, such as right atrial tachycardia. U.S. Provisional Patent Application No. 60/189,611, filed Mar. 15, 2000, the disclosure of which is hereby incorporated herein by reference, describes exemplary methods and analysis systems for localization and treatment of atrial fibrillation.
While the new body surface mapping techniques appear quite promising, the sensing systems that have been used to-date to measure the heart cycle signals along the body surface have remained less than ideal. The process of preparing patients by affixing known electrode arrays can be time consuming and difficult, even for the highly skilled researchers now developing these techniques. Additionally, many localization procedures will be performed in an electromagnetically “noisy” environment. For example, the imaging equipment (often biplane fluoroscopy), RF power sources, pacing catheters, and therapeutic probes in use in an electrophysiology lab can induce significant noise in the small amplitude voltage measurements on which many of the new arrhythmia localization techniques are based. These imaging, pacing, and treatment systems may also interfere with the ideal array sensing locations. Undesirable interactions between imaging, treatment and body surface mapping electrode arrays may lead to inconvenience and delays at best, and degraded performance and/or increased dangers to the patient at worst. In other words, while the known body surface mapping systems have been adequate for effective research, improved body surface mapping systems and methods would be desirable to allow these new techniques to be effectively, safely, and reliably applied by practicing doctors for treatment of patients.
In light of the above, it would be desirable to provide improved devices, systems, and methods for sensing heart cycle signals for localization of arrhythmias. It would be particularly beneficial if these improvements enhanced the efficiency of mounting an array upon a patient's torso, as well as increasing the adaptability of the arrays to a variety of patient external anatomies. It would further be beneficial if these improved arrays and body surface mapping methods provided improved safety, reliability, and sensing/localization accuracy, despite the normal variations in physician experience and skill, and without excessive degradation in overall system performance when used in a high electromagnetic noise environment such as an electrophysiology lab. It would further be beneficial to maximize overall system performance without excessive expenditure on individual sensing system components and/or sterilization/reuse procedures. Some or all of these goals are provided by the invention described hereinbelow.
II. Related Art
The following patents and publications may be relevant to the subject matter of the present invention, and their full disclosures are incorporated herein by reference:
U.S. Pat. No. 5,483,968 describes a Method and Apparatus for Analyzing the Electrical Activity of the Heart, and Electrical Clamping Connection Device is described in U.S. Pat. No. 5,733,151. A similar electrode connector is described in PCT Publication No. WO 97/49143. U.S. Pat. No. 6,047,206 which describes Generation of Localized Cardiac Measures, Related Systems, and/or Methods. Similar topics may also be discussed in one or more of U.S. Pat. Nos. 4,751,928; 4,974,598; 5,054,496; 5,634,469; 5,311,873; and 5,724,984.
Arne SippensGroenewegen, et al. described “
Body Surface Mapping During Pacing at Multiple sites in the Human Atrium: P Wave Morphology of Ectopic Right Atrial Activation,” in Circulation,
98:369-380 (1998). Heidi A. P. Peeters, et al. described related work in an article entitled, “
Clinical Application of an Integrated
3-
Phase Mapping Technique for Localization of the Site of Origin of Idiopathic Ventricular Tachycardia
,” in
Circulation,
99:1300-1311 (1999). Arne SippensGroenewegen, et al. described “
Value of Body Surface Mapping in Localizing the Site of O
Groenewegen Arne Sippens
Ransbury Terrance
Barrish, Esq. Mark D.
Jastrzab Jeffrey R.
Resolution Medical, Inc.
Townsend & Townsend & Crew LLP
LandOfFree
Multi-electrode panel system for sensing electrical activity... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-electrode panel system for sensing electrical activity..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-electrode panel system for sensing electrical activity... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3098019