title: Sequential cardiac responses during the respiratory cycle: patterns of change in systolic intervals.
mesh_terms: D000368:Aged; D002302:Cardiac Output; D002306:Cardiac Volume; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000502:physiology*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010701:Phonocardiography; D012119:Respiration