title: Hemodynamic observations on a yogic breathing technique claimed to help eliminate and prevent heart attacks: a pilot study.
abstract: OBJECTIVE
  This pilot study investigated the hemodynamics of a yogic breathing technique claimed "to help eliminate and prevent heart attacks due to abnormal electrical events to the heart," and to generally "enhance performance of the central nervous system (CNS) and to help eliminate the effects of traumatic shock and stress to the CNS."
  
  
  METHODS
  Parameters for (4) subjects were recorded during a preexercise resting period, a 31-minute exercise period, and a postexercise resting period.
  
  
  METHODS
  Parameters for subjects were recorded in a laboratory at the University of California, San Diego.
  
  
  METHODS
  Parameters for 3 males (ages 44, 45, 67) and 1 female (age 41) were recorded. One (1) subject (male age 45) had extensive training in this technique.
  
  
  METHODS
  This yogic technique is a 1 breath per minute (BPM) respiratory exercise with slow inspiration for 20 seconds, breath retention for 20 seconds, and slow expiration for 20 seconds, for 31 consecutive minutes.
  
  
  METHODS
  Fourteen beat-to-beat parameters were measured noninvasively and calculated for body surface area to yield: stroke index (SI), heart rate (HR), cardiac index, end diastolic index, peak flow, ejection fraction, thoracic fluid index, index of contractility, ejection ratio, systolic time ratio, acceleration index, and systolic, diastolic, and mean arterial pressures (MAPs). Left stroke work index (LSWI) and stroke systemic vascular resistance index (SSVRI) were calculated.
  
  
  RESULTS
  We report on SI, HR, MAP, LSWI, and SSVRI and how they can help to describe hemodynamicstate changes. This technique induces dramatic shifts in all hemodynamic variables during the 1 BPM exercise and can produce unique changes in the postexercise resting period after long-term practice that appears to have a unique effect on the brain stem cardiorespiratory center regulating the Mayer wave (0.1-0.01 Hz) patterns of the cardiovascular system.
  
  
  CONCLUSIONS
  Preclinical studies are warranted to examine the possible long-term effects of this technique that appear to reset a cardiorespiratory brain-stem pacemaker. We postulate that this effect may be the basis for the purported yogic health claim.
authors.affiliation: The Research Group for Mind-Body Dynamics, Institute for Nonlinear Science, University of California, San Diego, La Jolla, CA 92093-0402, USA. dsk@ucsd.edu
authors.forename: David S
authors.initials: DS
authors.lastname: Shannahoff-Khalsa
authors.forename: B Bo
authors.initials: BB
authors.lastname: Sramek
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Kennel
authors.forename: Stuart W
authors.initials: SW
authors.lastname: Jamieson
mesh_terms: D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000503:physiopathology; D001945:Breathing Exercises; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology / Q000517:prevention & control*; D016896:Treatment Outcome; D015013:Yoga