To the Editor.—
Excercise tests are now widely used, mainly for detection of ischemic heart diseases and evaluation of cardiovascular fitness. Yet those tests are not completely innocent; they may involve risks, among them postexercise "vagal reaction." This reaction appears mostly in untrained "vagotonic individuals" as a result of sudden vigorous physical effort. This phenomenon usually occurs in the first to third minute of the recovery period and is characterized by pallor, cold sweat, nausea, hypotension, and bradycardia. In its severe form, peripheral vascular collapse, marked sinus bradycardia and even sinus arrest may threaten the patient's life.
Report of a Case.—
A healthy 35-year-old male physician underwent an ergospirometric examination for evaluation of cardiovascular fitness. The examinee had been asymptomatic except for dizziness on a few occasions (when blood was drawn, or after prolonged standing). His daily routine was sedentary in nature and he did not engage in sports. Physical