Field stimulation about a discontinuity of the myocardium to capture the heart at reduced pacing thresholds
AssigneeMedtronic, Inc.
InventorsVinod Sharma, Xiaohong Zhou
Life of this patent
Estimating the term…
Abstract
Improved pacing thresholds for capturing the heart are achieved by forming a discontinuity in the cardiac tissue of the heart chamber, disposing a pacing electrode at a distance less than a space constant of the cardiac tissue from the discontinuity in the cardiac tissue, and applying a stimulus of a first polarity at an energy insufficient to cause the directly stimulated tissue adjacent to the pacing electrode to propagate a depolarization wave through the cardiac tissue mass of the heart chamber but sufficient to induce a transmembrane potential change at the tissue adjacent to the discontinuity that results in a propagated wave front. Thus, pacing energy is advantageously reduced.
Claims43
A method of applying pacing pulses to cardiac tissue having a myocardial space constant to effect depolarization of a cardiac tissue mass of a heart chamber comprising:
- forming a discontinuity in the cardiac tissue of the heart chamber;
- disposing a pacing electrode at a distance approximately less than the space constant of the cardiac tissue from the discontinuity in the cardiac tissue;
- and
- applying a stimulus to the cardiac tissue through the pacing electrode to form a depolarization region at the pacing electrode insufficient to propagate a depolarization wave front through the cardiac tissue mass of the heart chamber but sufficient to induce a transmembrane potential change at the tissue adjacent to the discontinuity that results in a propagated depolarization wave front to effect a contraction of the heart chamber.
A cardiac pacing lead of the type comprising an elongated cardiac lead body extending between a proximal electrode connector and a distal electrode head for applying pacing pulses to cardiac tissue having a myocardial space constant to effect depolarization of a cardiac tissue mass of a heart chamber comprising:
- discontinuity forming means supported on the electrode head for forming a discontinuity in the cardiac tissue of the heart chamber;
- and
- at least one pacing electrode supported by the electrode head and disposed at a distance less than the space constant of the cardiac tissue from the discontinuity forming means through which a pacing pulse can be delivered at an energy insufficient to cause the directly stimulated tissue adjacent to the pacing electrode to propagate a depolarization wave front through the cardiac tissue mass of the heart chamber but sufficient to induce a transmembrane potential change at the tissue adjacent to the discontinuity that results in a propagated wave front to effect a contraction of the heart chamber.
A method of applying pacing pulses to cardiac tissue having a myocardial space constant to effect depolarization of a cardiac tissue mass of a heart chamber comprising:
- forming an elongated discontinuity in the cardiac tissue of the heart chamber having first and second discontinuity sides;
- disposing an anodic pacing electrode at a distance less than the space constant of the cardiac tissue from the first side of the discontinuity in the cardiac tissue;
- disposing a cathodic pacing electrode at a distance less than the space constant from the second side of the discontinuity in the cardiac tissue;
- and
- applying a stimulus of a first polarity to the cardiac tissue through the anodic and cathodic pacing electrodes to form a cathodic depolarization region at the cathodic pacing electrode insufficient in volume to propagate a depolarization wave front through the cardiac tissue mass of the heart chamber but sufficient to induce a transmembrane potential change at the tissue adjacent to the discontinuity that results in a propagated depolarization wave front to effect a contraction of the heart chamber.
A cardiac pacing lead of the type comprising an elongated cardiac lead body extending between a proximal electrode connector and a distal electrode head for applying pacing pulses to cardiac tissue having a myocardial space constant to effect depolarization of a cardiac tissue mass of a heart chamber comprising:
- discontinuity forming means supported on the electrode head for forming an elongated discontinuity having first and second sides in the cardiac tissue of the heart chamber;
- an anodic pacing electrode supported by the electrode head and disposed at a distance less than the space constant of the cardiac tissue from the first side of the discontinuity forming means;
- and
- a cathodic pacing electrode supported by the electrode head and disposed at a distance less than the space constant of the cardiac tissue from the second side of the discontinuity forming means, wherein pacing pulses are delivered between the anodic and cathodic pacing electrodes at an energy insufficient to cause the directly stimulated tissue adjacent to the cathodic pacing electrode to propagate a depolarization wave through the cardiac tissue mass of the heart chamber but sufficient to induce a transmembrane potential change at the tissue adjacent to the discontinuity that results in a propagated depolarization wave front to effect a contraction of the heart chamber.
Dependencies are inferred from the claim text.