Heart rate studies are replete in the autonomic modification literature. It has been possible to produce significant heart rate level changes in even a single session, although it has been easier to get increases than decreases. There is a great deal of evidence to show that subjects can quite easily produce voluntary changes in both heart rate level and variability in multiple sessions (Engel and Hansen, 1966: Hnatiow and Lang, 1965). Heart rate training with premature ventricular contractions, atrial fibrillations and Wolff-Parkinson-White syndrome have been investigated (Engel, 1972). Heart rate feedback along with desensitization and implosion has been applied successfully to the management of anxiety about the heart (Wilkramaskera, 1974).
Clinically, heart rate training may be applicable in cardiac arrhythmias of many causes. The method involves an alternation of heart rate speeding and slowing, and, for obvious reasons, is best done in an in-patient coronary care setting.