Feasibility of spinal cord stimulation in angina pectoris in patients with chronic pacemaker treatment for cardiac arrhythmias.

Spinal cord stimulation (SCS) has been used since 1985 as additional symptom-relieving treatment for patients with severe angina pectoris despite optimal conventional medical and invasive treatment. SCS has antiischemic effects and is safe and effective in long-term use. Several patients with coronary artery disease also suffer from disorders that necessitate the use of a cardiac permanent pacemaker (PPM). The combination of SCS and PPM has previously been considered hazardous because of possible false inhibition of the PPM. To assess if thoracic SCS and PPM can be safely combined in patients with refractory angina pectoris, 18 patients treated with both SCS and PPM were tested. The PPM settings were temporarily modified to increase the probability of interference, while the SCS intensity (used in bipolar mode) was increased to the maximum level tolerated by the patient. Any sign of inhibition of the ventricular pacing was recorded by continuous ECG monitoring. With the aid of a questionnaire, symptoms of interference during long-term treatment were evaluated. No patient had signs of inhibition during the tests. Reprogramming of the pacemaker because of the test results was not needed in any of the patients. The long-term follow-up data revealed no serious events. This study indicates that bipolar SCS and PPM can be safely combined in patients with refractory angina pectoris. However, individual testing is mandatory to ascertain safety in each patient. A testing procedure for patients in need of SCS and PPM is suggested in this article.