Secure and Efficacious Therapy Delivery for a Pacing Engine

Abstract

The above-described methods and apparatus are believed to be of particular benefit for patients suffering heart failure including cardiac dysfunction, chronic HF, and the like and all variants as described herein and including those known to those of skill in the art to which the invention is directed. It will understood that the present invention offers the possibility of monitoring and therapy of a wide variety of acute and chronic cardiac dysfunctions. The current invention provides systems and methods for delivering therapy for cardiac hemodynamic dysfunction via the innervated myocardial substrate receives one or more discrete pulses of electrical stimulation during the refractory period of said innervated myocardial substrate.

1 . A method of safely delivering neurological therapy to an innervated myocardial substrate of a patient to improve cardiac performance via the innervated myocardial substrate of the ventricle, comprising the step of: 
 delivering electrical stimulation to at least one ventricular chamber of a heart during a refractory period of said chamber wherein said electrical stimulation impinges upon nerve fibers embedded in the myocardial substrate of the chamber and fails to evoke a depolarization response from myocytes present in the myocardial substrate.    
   
   
       2 . A method according to  claim 1 , wherein said electrical stimulation is delivered to at least two spaced apart sites of said ventricle.  
   
   
       3 . A method according to  claim 1 , wherein said electrical stimulation comprises at least three pulses of electrical stimulation.  
   
   
       4 . A method according to  claim 1 , wherein the electrical stimulation comprises a monophasic pulse having a pulse amplitude of between about five volts and 10 volts delivered at a frequency of between about 30 Hz and 70 Hz and wherein said pulse has a pulse width of between about one millisecond (ms) and about 3 ms.  
   
   
       5 . A method according to  claim 1 , further comprising the step of ceasing delivery of the electrical stimulation and reducing a blanking period for at least one sensing amplifiers.  
   
   
       6 . A method according to  claim 5 , further comprising: 
 determining whether an arrhythmia is present, and if not resuming the electrical stimulation.    
   
   
       7 . A method according to  claim 2 , wherein the spaced apart sites comprise a first location within a coronary vein associated with a left ventricle and a right heart location.  
   
   
       8 . A method according to  claim 7 , wherein the right ventricular location comprises one of a superior vena cava location and a right ventricular location.  
   
   
       9 . A method according to  claim 8 , wherein the right ventricular location includes a right apical location and a right septal location.  
   
   
       10 . A method according to  claim 6 , further comprising: 
 delivering additional electrical stimulation to a portion of non-cardiac tissue, and wherein the non-cardiac tissue comprises at least one of the following: a portion of vagal nerve, a portion of spinal cord nerve, a location proximate an autonomic nerve so that norephinephrine is released from said autonomic nerve in response to the delivered at least one non-excitatory stimulation pulse, a portion of subcutaneous tissue of said patient, a portion of epidermis of said patient.    
   
   
       11 . A method according to  claim 10 , wherein said additional electrical stimulation is delivered from a dedicated implantable device separate from that which produced the electrical stimulation.  
   
   
       12 . A method according to  claim 11 , further comprising, upon delivery of the additional electrical stimulation performing one of: 
 ceasing delivery of the electrical stimulation, and    ceasing determining whether an arrhythmia is present.    
   
   
       13 . A method of therapy delivery involving stimulation of a portion of a sympathetic nervous system of a patient for enhanced cardiac function, without stimulating the cardiac tissue sufficiently to evoke a depolarization of said cardiac tissue, comprising the step of: 
 delivering non-excitatory electrical stimulation to at least a portion of a sympathetic nerve disposed in at least a one of the following regions: a neck region, a chest region, a mediastimum region, a heart region of a patient so that said heart experiences improved mechanical function due at least in part to release of catecholamine substances.    
   
   
       14 . A method according to  claim 13 , wherein said portion of the sympathetic nerve is at least a one of the following: an ansa subclavia; a portion of a thoracic sympathetic nerve; a cardiac plexus; at least a portion of a one of an unnamed set of cardiac nerves disposed alongside a coronary vessel; a portion of an inferior cervical cardiac nerve.  
   
   
       15 . A method according to  claim 13 , wherein said non-excitatory electrical stimulation comprises at lest three discrete pulses and said pulses consist of pulsing having approximately 8 volts of amplitude delivered for approximately 1.5 milliseconds (ms) at approximately 50 Hz.  
   
   
       16 . A method according to  claim 15 , wherein said non-excitatory electrical stimulation is delivered for a fraction of a temporal period.  
   
   
       17 . A method according to  claim 16 , wherein said non-excitatory electrical stimulation is delivered at least approximately one hour out of six hours.  
   
   
       18 . A method of safely applying RPS stimulation pulse therapy to a chamber of a heart, comprising the steps of: 
 confirming that no arrhythmia is occurring for a predetermined number of cardiac cycles of a heart;    delivering a RPS stimulation therapy to a chamber of the heart; and    ceasing delivery of said RPS therapy upon detection of an arrhythmia.    
   
   
       19 . A method according to  claim 18 , wherein after ceasing delivery of said RPS therapy, further comprising the step of: 
 implementing a non-RPS therapy to a chamber of the heart.    
   
   
       20 . A method according to  claim 18 , wherein the RPS therapy comprises: 
 a plurality of pulses delivered at about 8 volts of amplitude, each pulse having a pulse width of approximately 1.5 milliseconds (ms) at approximately 50 Hz, and wherein the pulses are monophasic pulses.