Atrial defibrillator employing transvenous and subcutaneous electrodes and method of use

An apparatus for defibrillating the atrium of a patient's heart, comprising:

• a first defibrillation electrode means for location in the coronary sinus of said patient's heart;
• a second defibrillation electrode means for subcutaneous location in the left pectoral region of said patient's thorax;
• an implantable defibrillation pulse generator coupled to said first and second defibrillation electrodes;
• and
• means for sensing the occurrence of atrial fibrillation and for triggering the delivery of a defibrillation pulse between said first and second defibrillation electrodes in response to sensing the occurrence of atrial fibrillation.

An apparatus for defibrillating the atrium and ventricle of a patient's heart, comprising:

• a first defibrillation electrode means for location in the coronary sinus of said patient's heart;
• an implantable defibrillation pulse generator having a housing and having a first output coupled to said first defibrillation electrode;
• and
• a second defibrillation electrode comprising a conductive portion of said housing of said defibrillation pulse generator and coupled to a second output of said defibrillation pulse generator;
• means for sensing the occurrence of atrial fibrillation and for triggering the delivery of a defibrillation pulse at a first energy level between said first and second electrodes in response to sensing the occurrence of atrial fibrillation;
• and
• means for sensing the occurrence of ventricular fibrillation and for triggering the delivery of a defibrillation pulse at a second, higher energy level to at least one of said first and second electrodes in response to sensing the occurrence of ventricular fibrillation.

An apparatus for defibrillating the atrium and ventricle of a patient's heart, comprising:

• a first defibrillation electrode means for location in the coronary sinus of said patient's heart;
• a second defibrillation electrode means for subcutaneous location in the left pectoral region of said patient's thorax;
• an implantable defibrillation pulse generator coupled to said first and second defibrillation electrodes;
• means for sensing the occurrence of atrial fibrillation and for triggering the delivery of a defibrillation pulse at a first energy level between said first and second defibrillation electrodes in response to sensing the occurrence of atrial fibrillation;
• and
• means for sensing the occurrence of ventricular fibrillation and for triggering the delivery of a defibrillation pulse at a second, higher energy level to at least one of said first and second defibrillation electrodes in response to sensing the occurrence of ventricular fibrillation.

A method of defibrillating the atrium of a patient's heart, comprising:

• implanting a first transvenous defibrillation electrode lead in the coronary sinus of said patient's heart;
• subcutaneously implanting a defibrillation pulse generator, having a housing including a conductive portion and employing said conductive portion of said housing as a second, subcutaneous defibrillation electrode, in the left pectoral region of said patient's body;
• detecting the occurrence of atrial fibrillation;
• and
• delivering a defibrillation pulse between said first, transvenous defibrillation electrode and said portion of said housing of said defibrillation pulse generator.

A method of defibrillating the atrium of a patient's heart, comprising:

• implanting a first, transvenous defibrillation electrode lead in the coronary sinus of said patient's heart;
• subcutaneously implanting a defibrillation pulse generator in said patient's body and a second, subcutaneous defibrillation electrode in the left pectoral region of said patient's body;
• detecting the occurrence of atrial fibrillation;
• and
• delivering a defibrillation pulse between said first, transvenous defibrillation electrode and said second, subcutaneous defibrillation electrode.

A method of defibrillating the atrium and ventricle of a patient's heart, comprising:

• implanting a first transvenous defibrillation electrode lead in the coronary sinus of said patient's heart;
• subcutaneously implanting a defibrillation pulse generator, having a housing including a conductive portion and employing said conductive portion of said housing as a second, subcutaneous defibrillation electrode, in the left pectoral region of said patient's body;
• detecting the occurrence of atrial or ventricular fibrillation;
• and
• delivering a defibrillation pulse at a first energy level between said first, transvenous defibrillation electrode and said portion of said housing of said defibrillation pulse generator following detection of atrial fibrillation and following detection of ventricular fibrillation delivering a pulse of a second energy level, higher than said first energy level, to at least one of said first electrode and said housing.

A method of defibrillating the atrium and ventricle of a patient's heart, comprising:

• implanting a first, transvenous defibrillation electrode lead in the coronary sinus of said patient's heart;
• subcutaneously implanting a defibrillation pulse generator, in said patient's body and a second, subcutaneous defibrillation electrode, in the left pectoral region of said patient's body;
• detecting the occurrence of atrial or ventricular fibrillation;
• and
• delivering a defibrillation pulse a first energy level between said first, transvenous defibrillation electrode and said second electrode following detection of atrial fibrillation at and following detection of ventricular fibrillation delivering a pulse of a second energy level, higher than said first energy level, to at least one of said first and second electrodes.