Cardiac drug delivery system

A process for treating an arrhythmogenic site in cardiac tissue, including:

• locating an arrhythmogenic site;
• using a catheter to intraluminally deliver an electrode to the arrhythmogenic site, and to implant the electrode at the site, causing a portion of the electrode to penetrate cardiac tissue at the site;
• after implantation, delivering a therapeutic agent to the cardiac tissue at the site;
• sensing an electrical condition of the cardiac tissue proximate the site after said delivery of the therapeutic agent has begun, to evaluate whether said delivery of the therapeutic agent has had a desired effect;
• and performing alternatively, one of the following steps:
• (i) using the electrode to deliver RF energy to said cardiac tissue at the site to ablatively destroy the tissue;
• and
• (ii) using the catheter to remove and reposition said electrode responsive to determining that administration of the therapeutic agent has not had the desired effect.

A process for effecting a controlled, transient delivery of a therapeutic agent to cardiac tissue, including:

• using an elongate and flexible catheter that supports at its distal end an electrode that includes a distal penetrating element, to intraluminally deliver the electrode to a selected cardiac tissue site and to implant the electrode at said site to insert the penetrating element to a depth within the cardiac tissue, whereby the penetrating element is surrounded by the cardiac tissue;
• after the electrode is implanted, sensing electrical impulses conducted through the penetrating element and an elongate conductor coextensive with the catheter and electrically coupled to the penetrating element, thus to monitor an electrical condition of the surrounding tissue for an arrhythmic event;
• responsive to sensing an arrhythmic event, delivering a therapeutic agent through said electrode and to the surrounding cardiac tissue through an opening in the penetrating element, thus to effect a delivery to a depth within the surrounding cardiac tissue;
• after said delivery, further monitoring the electrical condition of the surrounding tissue to determine whether the delivery has terminated the arrhythmia.

A device for treating cardiac tissue locally to a depth within the cardiac tissue, including:

• an elongate, flexible, dielectric and biocompatible catheter body;
• an electrically conductive implantable first electrode supported at a distal end of the catheter body and including a distally located penetrating element adapted to penetrate cardiac tissue to a depth within surrounding cardiac tissue;
• an elongate and flexible electric conductor extending along the catheter body and electrically coupled to the implantable first electrode at a proximal portion thereof;
• a fluid passage through the electrode, open to an exterior of the electrode at said proximal portion and at said penetrating element;
• a therapeutic agent source, fluid coupled to the fluid passage at the proximal portion, for delivering therapeutic agents to the surrounding cardiac tissue via the fluid passage;
• and
• a second electrode positionable in proximate, spaced apart relation to said first electrode, and a voltage biasing means adapted to bias the first electrode and the second electrode with respect to one another to generate RF current between the first and second electrodes.

A transmiocardial revascularization device, including:

• an elongate, flexible, dielectric and biocompatible catheter body;
• an implantable component supported at a distal end of the catheter body and including a distally located penetrating element adapted to penetrate cardiac tissue to a depth within surrounding cardiac tissue;
• a means for providing tissue altering energy to form channels within said surrounding cardiac tissue;
• a fluid passage through the implantable component open to an exterior of the implantable component at a proximal end portion thereof and at said penetrating element;
• a therapeutic agent source, fluid coupled to the fluid passage at said proximal portion, for delivering therapeutic agents to the surrounding cardiac tissue via the fluid passage.