A survey of pre–operative fear*

Fear is an emotion.It cannot be measured objectively but only subjectively and by observing the physiological response to it.It is a long appreciated concept that emotion has a profound effect on the action of the heart.Fifteen hundred years before the birth of Christ, the description 'the trembling heart of fear' was used in the Old Testa-ment1.It was reported thirty-two years ago that reaction to fear can produce transitory electro-cardiographic changes in the T waves2.Nine years later, it was demonstrated that premature cardiac contractions could be produced experimentally during the discussion of sensitive topics 3.More recently, the emotional interaction with cardiac states has again been investigated.In one study the interpersonal conflict in a closed group of men was observed4, and in another, the cardiac response in Scuba divers was noted and co-related with psychological factors5.The arrhythmias commonly noted in patients whose cardiac rhythm has been influenced by emotional over-reaction are, paroxysmal tachycardia, premature contractions, atrial fibrillation and flutter and, occasionally, ventricular tachycardias.The precipitation of ectopic rhythms by psychogenic factors may result from many causes.Stimuli from the central nervous system may affect both the sympathetic and parasympathetic systems and the endocrine system and especially the thyroid and adrenal glands.These factors actjng alone or in combination, result in increased cardiac excitability7.Fear activates the sympathetic nervous system causing constriction of the blood vessels innervated by a-receptors, dilatation of blood vessels innervated by preceptors, increase in heart rate and blood pressure.The constrictions of digital vessels have been measured with a digital plethysmograph and these results used as an objective measurement of anxietys.A case in which terror may have led to adrenergic hyperactivity and the collapse of the patient was reported in 19529 and more recently the occurrence of ventricular fibrillation in a terrified patient during the use of drugs which sensitise the heart to adrenaline was described 10.