Effects of Spinal Cord Stimulation and Coronary Artery Bypass Grafting on Myocardial Ischemia and Heart Rate Variability: Further Results from the ESBY Study

In the present study, 24-hour ECG recordings were analyzed from the Electrical Stimulation versus Coronary Artery Bypass Surgery (ESBY) Study where spinal cord stimulation was compared to CABG (coronary artery bypass grafting) in selected patients with severe angina pectoris. During the monitoring period, the spinal cord stimulation was discontinued to evaluate possible long-term effects of this treatment. The number of ischemic episodes and the duration of ischemia decreased in the CABG group at the follow-up when compared to spinal cord stimulation (p < 0.05). In spite of this, the number of anginal attacks decreased (p < 0.0001) in both groups. The fact that the anginal symptoms decreased in the spinal cord stimulation group in spite of discontinued stimulation and lack of effects on ischemic ST changes could indicate a long-term primary analgesic effect of this treatment in addition to the well-documented acute anti-ischemic effect.