ABSTRACT
Spinal cord electrical stimulation [SCS] has been shown to be a treatment option forpatients suffering from angina pectoris CCS III-IV although being on optimal medication and notsuitable for conventional treatment strategies, e.g. CABG or PTCA. Although many studiesdemonstrated a clear symptomatic relief under SCS therapy, there are only a few short-term studies that investigated alterations in cardiac ischemia. Therefore, doubts remain whether SCS has a direct effect on myocardial perfusion. A prospective study to investigate the short- and long-term effect of spinal cord stimulation [SCS] on myocardial ischemia in patients with refractory angina pectoris and coronary multivesseldisease was designed. Myocardial ischemia was measured by MIBI-SPECT scintigraphy 3 months and 12 months after the beginning of neurostimulation. To further examine the relation between cardiac perfusion and functional status of the patients, we measured exercise capacity [bicycle ergometry and 6-minute walk test], symptoms and quality of life [Seattle Angina Questionnaire [SAQ]], as well. 31 patients [65 +/- 11 SEM years; 25 male, 6 female] were included into the study. The average consumption of short acting nitrates [SAN] decreased rapidly from 12 +/- 1.6 times to 3 +/- 1 times per week. The walking distance and the maximum workload increased from 143 +/- 22 to 225 +/- 24 meters and 68 +/- 7 to 96 +/- 12 watt after 3 months. Quality of life increased [SAQ] significantly after 3 month compared to baseline, as well. No further improvement was observed after one year of treament. Despite the symptomatic relief and the improvement in maximal workload computer based analysis [Emory Cardiac Toolbox] of the MIBI-SPECT studies after 3 months of treatment did not showsignificant alterations of myocardial ischemia compared to baseline [16 patients idem, 7 with increase and 6 with decrease of ischemia, 2 patients dropped out during the initial test phase]. Interestingly, in the long-term follow up after one year, 16 patients [of 27 who completed the one year follow up] showed a clear decrease of myocardial ischemia and only one patient still had an increase of ischemia compared to baseline. Thus, spinal cord stimulation not only relieves symptoms, but reduces myocardial ischemia as well. However, since improvement in symptoms and exercise capacity starts much earlier, decreased myocardial ischemia might not be a direct effect of neurostimulation but rather be due to a better coronary collateralisation because of an enhanced physical activity of the patients. Heart Views. 2005;6[2]:63-70