摘要 |
A medical interventional device is structured for implantation in a human patient, to respond to detection of cardiac activity of the patient indicative of cardiac dysrhythmias. The device includes a cardiac therapy system responsive to a detected arrhythmia in either the atrial or ventricular chambers for automatic therapeutic treatment by selective application of an appropriate therapy regimen consisting of pacing, cardioverting or defibrillating waveforms of predetermined type and energy content to the chamber diagnosed as that in which the dysrhythmia originated. The device incorporates a DDD or DDD-R pacemaker for dual chamber sensing of electrical (ECG) activity, and for constant atrioventricular synchronization. A microprocessor-based logic subsystem is used for diagnosis of the origin of a rhythm disorder including identification of the originating heart chamber. The electrode system for delivering the selected therapy regimen includes a single lead for pacing, sensing, cardioversion and defibrillation associated with each of the right atrial and ventricular chambers. A counter-electrode for defibrillation may be the metal case in which the device electronics are housed. A cardiac electrode implanted in the distal coronary sinus enables improved defibrillation and left heart stimulation for improved hemodynamic response. Dual chamber rate responsive pacing further improves hemodynamics.
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