[Short latency somatosensory evoked potentials in patients with ischemic heart disease]

Short latency somatosensory evoked potentials (SSEP) to median nerve stimulation recorded from post-Rolandic area and the surface of processus spinosus of Cvs at the same record time. To assess electrophysiologically functional status of central nervous system (CNS), SSEP were studied in 43 patients with ischemic heart disease (IHD); 18 cases of angina pectoris (AP group), 25 cases of old myocardial infarction (MI group), and 14 non-IHD controls (NC group). The N13, N20, P25 peak latencies (PLs) and the central conduction time (CCT, the peak latency between N13 and N20) in AP group or MI group were prolonged remarkably compared with NC group. Likewise, MI group showed significant prolongation of N20, P25 PLs and CCT compared to the AP group. Furthermore, in MI group, the N20 peak amplitude was significantly lowered; the subjects percentages of the N20 or P25 amplitude detraction more than 40 percent in one side and the P25 interextremital latency difference over 1 ms were significantly increased than those of the NC group. These results suggested the pathological changes of the somatosensory pathway from superior spinal cord or medulla oblongata to cerebral cortex primary sensory area in CNS in the IHD patients.