T-wave amplitude (TWA) appears unlikely to be a reliable index of myocardial sympathetic activity, at variance with what has previously been proposed. (1) TWA is not influenced consistently by stimulation or blockade of the cardiac sympathetic nerves. (2) Electrocardiographic lead selection can influence the direction and magnitude of change in TWA. (3) Sympathetic influences on the heart are exerted via alpha or beta receptors. While other non-invasive indices (pre-ejecton period, pulse transit time) differentiate these effects, there is no evidence that TWA does. (4) Data on TWA derived from studies of patient populations may not be relevant to normal subjects. (5) Non-neural factors can have important effects on TWA. We discourage further serious consideration of TWA as an index of myocardial sympathetic activity.
|Number of pages||6|
|Publication status||Published - 1983|
ASJC Scopus subject areas
- Physiology (medical)
- Experimental and Cognitive Psychology
- Neuropsychology and Physiological Psychology