Vectorcardiographic Results of Human Exposures to +3GZ, +5GZ, and +7GZ

摘要

Frank orthogonal vectorcardiograms (VCG) were recorded from 10 subjects before, during, and for 15 min after exposures to +3Gz +5Gz, and +7Gz. The order of acceleration exposure was randomized, with the individual exposures separated by at least one week. Standard USAF anti-G suits were worn by all subjects. Detailed analysis of the scalar lead electrocardiograms revealed no abnormalities and no consistent signs of conduction disturbances or ischemic ST-T segment changes. During +Gz stress, the QRS axis of the VCG demonstrated posterior rotation in the sagittal plan, and counterclock wise rotation in the transverse plane. The changes in the VCGs recorded during +Gz stress appeared to be related to rotational changes of the heart due to mechanical stress and/or motion within the thorax. There were no ECG or VCG changes indicative of myocardial ischemia and/or damage during or after +Gz stress. Comprehensive data obtained in this study are presented here. (Author)