Influences of the adrenergic nervous system on the repolarization phase of the electrocardiogram

The following conclusions can be drawn : (1) The nervous outflow to the heart may be varied from the baseline to opposite directions by different stressful stimuli. (2) ST-T alterations may be induced and abolished by adrenergic activation and inhibition respectively. (3) These effects are dissociated from or not necessarily associated with an exaggerated responsiveness of the cardiac beta receptors. (4) The adrenergic influences on the ST-T abnormalities of myocardial ischemia and hypertension are limited.