Abstract: A device and method for ablating tissue includes a sheath system with an occlusion structure. In certain embodiments, arrhythmias originating in pulmonary veins are treated cryogenically.

Abstract: A device and method for ablating tissue includes a sheath system with an occlusion structure. In certain embodiments, arrhythmias originating in pulmonary veins are treated cryogenically.

Abstract: A device and method for ablating tissue includes a sheath system with an occlusion structure. In certain embodiments, arrhythmias originating in pulmonary veins are treated cryogenically.

Abstract: A device and method for ablating tissue includes a sheath system with an occlusion structure. In certain embodiments, arrhythmias originating in pulmonary veins are treated cryogenically.

Abstract: A catheter for ablating internal tissue using radiofrequency (rf) or ultrasonic energy includes a mechanism to cool the catheter's distal tip. The catheter also includes either an rf electrode or an ultrasonic transducer positioned at the tip to direct energy into the internal tissue for tissue ablation. With the distal tip of the catheter positioned adjacent the target tissue, a refrigerant is introduced into the catheter and allowed to expand near the catheter's distal tip. During expansion, the fluid refrigerant transitions from a liquid state to a gaseous state. Latent heat absorbed during the phase transition cools the tip of the catheter to a temperature sufficient to prevent tissue charring and coagulum formation during ablation. In another implementation, the catheter tip is cooled to a temperature sufficient to freeze tissue and create an ice-ball at the catheter tip that stabilizes the tip relative to the target tissue.

Abstract: A drainage tube for controlling a patient's temperature and draining fluids from a patient's chest or other body cavity includes a generally tubular elongate body having one or more drainage lumens with one or more drainage ports disposed along the distal portion of the drainage tube. The drainage tube also comprises one or more flow lumens for transporting a heat exchange fluid to one or more heat exchange elements that exchange heat with tissue in the patient's chest or other body cavity. The drainage tube may have an internal heating element that heats or cools the heat exchange fluid. A heat exchange element may include an everting balloon that expands out of a cavity in the elongate body after intubation of the drainage tube. The expansion of the everting balloon may be assisted with a moveable inner shaft disposed in the elongate body.

Abstract: A device and method for ablating tissue includes a sheath system with an occlusion structure. In certain embodiments, arrhythmias originating in pulmonary veins are treated cryogenically.

Abstract: An implantable atrial defibrillator includes a lead system having a plurality of electrodes to deliver a cardioverting pulse to atria of a heart, for sensing A waves of the heart, and for sensing R waves of the heart. A first detector detects the A waves sensed by the lead system and a second detector detects the R waves sensed by the lead system. An inhibit stage defines an inhibit time period responsive to each detected R wave and an output provides the cardioverting pulse to the lead system responsive to an A wave being detected. The inhibit stage precludes provision of the cardioverting pulse during each inhibit time period.

Abstract: An implantable atrial cardiovertor applies cardioverting electrical energy to atria of a heart with reduced discomfort to a patient. The cardiovertor includes a storage capacitor having a capacitance and a discharge control for controlling discharge of the storage capacitor to apply the cardioverting electrical energy to the atria of the heart. The discharge control causes the applied cardioverting electrical energy to have a biphasic waveform having a first phase and a second phase of opposite polarity and equal time duration. The time durations of the first and second phases are each greater than four milliseconds, and the capacitance of the storage capacitor is greater than or equal to 120 .mu.F.

Abstract: A post-surgical atrial cardioverting, atrial pacing, and ventricular pacing system and lead system provides for cardioverting the atria, pacing the atria, and/or pacing the ventricles of the heart of a post-surgical heart patient. The system includes a first lead and a second lead providing a pair of atrial cardioverting electrodes, an atrial pacing electrode, and a ventricular pacing electrode. The electrodes are electrically isolated from each other. The system further includes at least one anchor releasably disposing the electrodes beneath the skin of the patient with each atrial cardioverting electrode electrically contacting a respective given one of the atria, the atrial pacing electrode electrically contacting one of the atria, and the ventricular pacing electrode electrically contacting a ventricle.

Abstract: An implantable atrial defibrillator includes a cardiovertor for applying cardioverting electrical energy to the atria of a heart when the atria are in need of cardioversion. The defibrillator further includes a pacer for pacing the atria of the heart immediately after each application of cardioverting electrical energy to the atria of the heart. A rate control commences the pacing at a relatively high first rate and gradually reduces the rate to a lower second rate.

Abstract: An implantable atrial defibrillator provides adaptive output voltage control. An atrial cardiovertor is responsive to an atrial fibrillation detector for applying a cardioverting voltage having a magnitude to the atria of a heart when the atria are in need of cardioversion. A memory stores data associated with each such voltage application. A computation stage computes from the stored data a percentage of success which is compared to lower and upper limits. The output voltage is incremented or decrement based upon the comparison. The output voltage may further be maintained within a fixed preselected voltage range.

Abstract: An implantable atrial defibrillator includes a cardiovertor for applying cardioverting electrical energy to the atria of a heart when the atria are in need of cardioversion. The defibrillator further includes a pacer for pacing the atria of the heart immediately after each application of cardioverting electrical energy to the atria of the heart. The atria are paced in a demand mode and for a finite time period.

Abstract: An atrial cardiovertor/defibrillator provides therapy to the atria corresponding to the type of atrial arrhythmia occurring in the atria of the heart. The atrial cardiovertor/defibrillator includes a memory for storing respective different criteria for each of different types of atrial arrhythmia, a sensor for sensing activity of at least one of the atria of the heart to provide an electrogram signal, and a cardiovertor for providing a corresponding therapy to the heart for each of the different types of atrial arrhythmia. The cardiovertor/defibrillator further includes an atrial arrhythmia detector responsive to the electrogram signal and the stored criteria for identifying one of the types of atrial arrhythmia to cause the cardiovertor to provide therapy to the heart corresponding to the identified atrial arrhythmia.

Abstract: An atrial defibrillator and method provides cardioverting electrical energy to the atria of a human heart after timing successive R to R intervals. A detector detects ventricular activations of the heart and a timer times intervals between immediately successive ventricular activations. A cardiovertor applies cardioverting electrical energy to the atria of the heart when a second time interval between a third ventricular activation and a second ventricular activation immediately preceding the third ventricular activation satisfies a predetermined criteria with respect to a first time interval between the second ventricular activation and a first ventricular activation immediately preceding the second ventricular activation.

Abstract: An intravenous lead for use with a cardiac device for implantation in the coronary sinus or the coronary sinus and great cardiac vein of the heart provides positive fixation for the lead when implanted in the coronary sinus or the coronary sinus and great vein of the heart. The lead includes a lead body adapted to be fed into the coronary sinus and great vein of the heart of a patient and at least one electrode carried by the lead body and adapted to be coupled to the implantable cardiac device. The lead body includes a preformed section having a resiliently coiled configuration. The coiled section is a left-handed turned coiled section which provides superior positive fixation of the lead as compared to right-handed turned coiled sections for use in the coronary sinus and great cardiac vein.

Abstract: A catheter insertable into a body provides for both sensing electrical activity of the heart at localized locations of the heart and defibrillating the heart when defibrillation is required. The catheter includes a plurality of connectors at the proximal end and a plurality of electrodes disposed along the catheter at the distal end. The plurality of electrodes includes a first plurality of electrodes and a second plurality of electrodes. The first plurality of electrodes are coupled together and to a given one of the plurality of connectors. Each of the second plurality of electrodes is coupled to a respective different one of the plurality of connectors. The first plurality of electrodes provide for defibrillating the heart and the second plurality of electrodes provide for sensing electrical activity of the heart at localized locations of the heart.

Abstract: A post-surgical cardioverting system and method applies cardioverting electrical energy to the atria of the heart of a post-surgical heart patient. The system includes a first lead including a first elongated electrode having a proximal end and a distal end, a second lead including a second elongated electrode having a proximal end and a distal end, and sutures for releasably anchoring the distal ends of the first and second electrodes to the pericardium and disposing the first and second electrodes along the pericardium overlying the right and left atria respectively. A non-implantable cardiovertor is coupled to the first and second leads for applying the cardioverting electrical energy to the first and second electrodes. When cardioversion is no longer required, the first and second leads may be pulled out of the patient's chest.

Abstract: An implantable atrial defibrillator cardioverts the atria of a patient's heart and determines the quantity of cardioverting electrical energy required for cardioverting the atria of the patient. The atrial defibrillator includes a detector for detecting atrial activity of the heart and an atrial fibrillation detector for determining when the atria of the heart are in fibrillation. A delivery stage is selectively operable in a test mode for applying fibrillation inducing electrical energy to the atria when the atria are not in fibrillation for inducing fibrillation. When fibrillation is induced, the delivery stage repeatedly applies test cardioversion electrical energy to the atria until the atria are cardioverted. Thereafter, a value indicative of the quantity of the test cardioversion energy last applied to the atria is stored for future reference when the atrial defibrillator is in a normal operating mode.

Abstract: A post-surgical cardioverting system and method applies cardioverting electrical energy to the atria of the heart of a post-surgical heart patient. The system includes a first lead including a first elongated electrode having a proximal end and a distal end, a second lead including a second elongated electrode having a proximal end and a distal end, and sutures for releasably anchoring the distal ends of the first and second electrodes to the pericardium and disposing the first and second electrodes along the pericardium overlying the right and left atria respectively. A non-implantable cardiovertor is coupled to the first and second leads for applying the cardioverting electrical energy to the first and second electrodes. When cardioversion is no longer required, the first and second leads may be pulled out of the patient's chest.