Implantable defibrillator with fibrillation-inducing capability and method for inducing fibrillation
First Claim
1. An implantable defibrillator comprising:
- a capacitor;
a voltage source;
electrode means for delivering electrical energy in vivo to a heart;
switch means for connecting said capacitor either across said voltage source or across said electrode means; and
control means for operating said switch means to connect said capacitor across said voltage source until said capacitor is charged to a voltage for defibrillation of said heart and, at selected times, to artificially induce ventricular fibrillation in said heart by connecting said capacitor across said voltage source until said capacitor is charged to a prescribed charging voltage which is significantly below said voltage for defibrillation and thereafter disconnecting said capacitor from said voltage source and connecting said capacitor across said electrode means during a plurality of spaced time intervals in a sequence.
2 Assignments
0 Petitions
Accused Products
Abstract
An implantable defibrillator has a capacitor which, through a controllable switch arrangement, can either be connected to a voltage source for charging the capacitor, or connected across electrodes placed at the heart for delivering a defibrillation pulse. To calculate the minimum pulse energy required for successful defibrillation, ventricular fibrillation is first induced, so that a plurality of defibrillation attempts, with energy increasing from attempt-to-attempt can be undertaken until successful defibrillation occurs. For inducing ventricular fibrillation, the capacitor of the implantable defibrillator is connected to the voltage source until a prescribed charging voltage, which is significantly below the voltage necessary for defibrillation, is reached, and subsequently, the capacitor is disconnected from the voltage source during brief time spans at intervals within the framework of a sequence and is connected during those time spans to the electrodes. Between the time spans, the capacitor is again charged.
75 Citations
12 Claims
-
1. An implantable defibrillator comprising:
-
a capacitor; a voltage source; electrode means for delivering electrical energy in vivo to a heart; switch means for connecting said capacitor either across said voltage source or across said electrode means; and control means for operating said switch means to connect said capacitor across said voltage source until said capacitor is charged to a voltage for defibrillation of said heart and, at selected times, to artificially induce ventricular fibrillation in said heart by connecting said capacitor across said voltage source until said capacitor is charged to a prescribed charging voltage which is significantly below said voltage for defibrillation and thereafter disconnecting said capacitor from said voltage source and connecting said capacitor across said electrode means during a plurality of spaced time intervals in a sequence. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method for in vivo delivery of electrical energy to the heart, said method comprising the steps of:
-
implanting a defibrillator and electrodes in a patient, said defibrillator containing a voltage source and a capacitor; disposing said electrodes relative to said heart for in vivo delivery of electrical energy from said defibrillator to said heart; connecting said capacitor across said voltage source until said capacitor reaches a voltage for defibrillation of said heart and, in the event of fibrillation discharging said capacitor across said electrodes; connecting said capacitor to a voltage source until said capacitor reaches a prescribed charging voltage which is significantly below said voltage for defibrillation for inducing fibrillation in said heart at selected times; after reaching said prescribed charging voltage, disconnecting said capacitor from said voltage source and connecting said capacitor across said electrodes for a plurality of spaced time intervals in a sequence; and re-connecting said capacitor across said voltage source between said time intervals for charging said capacitor. - View Dependent Claims (8, 9, 10, 11, 12)
-
Specification