Coordinating respiratory and cardiovascular hemodynamics

Abstract

The present invention is generally directed to methods, systems, and computer program products for coordinating musculoskeletal and cardiovascular hemodynamics. In some embodiments, a heart pacing signal causes heart contractions to occur with an essentially constant time relationship with respect to rhythmic musculoskeletal activity. In other embodiments, prompts (e.g., audio, graphical, etc.) are provided to a user to assist them in timing of their rhythmic musculoskeletal activity relative to timing of their cardiovascular cycle. In further embodiments, accurately indicating a heart condition during a cardiac stress test is increased.

1 - 5 . (canceled) 
     
     
         6 . A method of determining a timing of a heart pacing signal using a respiratory timing of the individual, the method performed by an implantable processor and comprising:
 receiving signals from at least one respiratory sensor positioned in or on the individual;   determining from the sensor signals a rhythmic musculoskeletal pump rate and a rhythmic musculoskeletal pump timing of the individual;   determining a target heart rate range for the individual, relative to the rhythmic musculoskeletal pump timing;   determining whether a current heart rate is in the target heart range and is an integer multiple of the rhythmic musculoskeletal pump rate; and   when the current heart rate is in the target heart range and is the integer multiple of the rhythmic musculoskeletal pump rate, outputting a pacing signal to the heart of the individual to pace the heart in the target heart rate range to increase musculoskeletal counterpulsation from musculoskeletal blood pumping, thereby providing at least one of: an increase in cardiac preload or an increase in cardiac stroke volume.   
     
     
         7 . The method of  claim 6 , further comprising receiving second signals from a cardiovascular cycle sensor for detecting a cardiac cycle of a patient; and determining the target heart rate range based on the second signals. 
     
     
         8 . The method of  claim 7 , further comprising determining the current heart rate of the individual. 
     
     
         9 . The method of  claim 6 , further comprising receiving second signals from a musculoskeletal activity sensor; and determining a step timing of the individual based on the second signals. 
     
     
         10 . The method of  claim 9 , further comprising outputting a breathing guidance to the individual to coordinate a breath timing with the step timing of the individual. 
     
     
         11 . A dynamic pacemaker system for artificially pacing a patient's heart, comprising:
 a respiratory sensor for detecting a respiratory timing of a patient;   an implantable electrical lead connectable to a heart of the patient;   an implantable pulse generator coupled to the electrical lead and configured, with the electrical lead, to electrically stimulate the heart in accordance with a pacing signal; and   an implantable processor electrically coupled to the respiratory sensor and the pulse generator, wherein the processor is configured to perform a method comprising:
 receiving signals from the respiratory sensor; 
 determining from the sensor signals a rhythmic musculoskeletal pump rate and a rhythmic musculoskeletal pump timing of the individual; 
 determining a target heart rate range for the patient, relative to the rhythmic musculoskeletal pump timing; 
 determining whether a current heart rate is in the target heart range and is an integer multiple of the rhythmic musculoskeletal pump rate; and 
 when the current heart rate is in the target heart range and is the integer multiple of the rhythmic musculoskeletal pump rate, outputting a pacing signal to the heart of the individual to pace the heart in the target heart rate range to increase musculoskeletal counterpulsation from musculoskeletal blood pumping, thereby providing at least one of: an increase in cardiac preload or an increase in cardiac stroke volume. 
   
     
     
         12 . The dynamic pacemaker system of  claim 11 , further comprising a cardiovascular cycle sensor for detecting a cardiac cycle of the patient, wherein the processor is further configured to receive second signals from the cardiovascular cycle sensor; and determine the target heart rate range based on the second signals. 
     
     
         13 . The dynamic pacemaker system of  claim 12 , wherein the processor is further configured to determine the current heart rate of the individual. 
     
     
         14 . The dynamic pacemaker system of  claim 12 , wherein the cardiovascular cycle sensor comprises one of: an electrocardiogram, a photoplethysmogram, or an electronic auscultation sensor. 
     
     
         15 . The dynamic pacemaker system of  claim 11 , further comprising a musculoskeletal activity sensor, wherein the processor is configured to receive second signals from the musculoskeletal activity sensor; and determine a step timing of the individual based on the second signals. 
     
     
         16 . The dynamic pacemaker system of  claim 15 , wherein the processor is configured to output a breathing guidance to the individual to coordinate a breath timing with the step timing of the individual. 
     
     
         17 . The dynamic pacemaker system of  claim 15 , wherein the musculoskeletal activity sensor comprises one of: a uniaxial accelerometer, a multiaxial accelerometer, a magnetometer, a gyroscope, a piezoelectric material, or a pressure sensor. 
     
     
         18 . The dynamic pacemaker system of  claim 11 , wherein the respiratory sensor is positioned within an artificial pacemaker implanted in the individual. 
     
     
         19 . The dynamic pacemaker system of  claim 11 , wherein the respiratory sensor is an external wireless sensor.