CARDIOVASCULAR STRESS (ELECTROCARDIOGRAPHIC CHANGES) PRODUCED BY DRIVING AN AUTOMOBILE

A review of cardiovascular changes during driving an automobile is presented. The heart rate responds instantaneously to critical situations and in stressful situations such as car racing increases rapidly to frequencies of 200 per minute or more. Blood pressure is less responsive. Significant ST depression and T wave changes were reported in healthy drivers and more so in ambulatory patients with coronary heart disease or in hyperreactors. In the experimental part, significant changes of the T wave in the ECG are reported which occurred in five men (having normal resting and postexercise ECG's) while driving an automobile over distances of 200 to 2,600 miles. The previously positive T wave of a bipolar manubrium-C5 lead, similar in pattern of V5, decreased to half its original size in one subject after three hours of driving. Transient flattening or inversion of the T wave developed in two other subjects after one to four hours of driving with some correlation to road events. The changes recovered partially during rest periods. The repeatability of ECG changes in eight drives over the same route (suburban and urban driving during rush hour) was quite good. © 1968.