Increased sympathetic tone in the left arm of patients affected by symptomatic myocardial ischemia.

Six of 60 consecutive patients (10%) affected by symptomatic myocardial infarction complained of positive sensory disturbances at the left arm, consisting of more or less painful burning sensation, heaviness, pins and needles. The sympathetic tone checked by means of fingertips photoplethismography showed a reduction in the maximal amplitude as well as in the amplitude of the wave measured at the 50% of its descending time in the left arm, as an expression of a local increase in the sympathetic tone. The need for an early diagnosis and therapy to prevent a clear sympathetic algodystrophy is stressed.