Symptomatic relief precedes improvement of myocardial blood flow in patients under spinal cord stimulation

BACKGROUND: Spinal cord electrical stimulation (SCS) has shown to be a treatment option for patients suffering from angina pectoris CCS III-IV although being on optimal medication and not suitable for conventional treatment strategies, e.g. CABG or PTCA. Although many studies demonstrated 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. METHODS: 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 multivessel disease 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. RESULTS: 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 show significant alterations of myocardial ischemia compared to baseline (16 patients idem, 7 with increase and 6 with decrease of ischemia, 2 patients dropped out during 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. CONCLUSION: 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

Immediate and short-term pain relief by acute sciatic nerve press: a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Despite much research, an immediately available, instantly effective and harmless pain relief technique has not been discovered. This study describes a new manipulation: a "2-minute sciatic nerve press", for rapid short-term relief of pain brought on by various dental and renal diseases.</p> <p>Methods</p> <p>This randomized, single-blind, placebo-controlled trial ran in three hospitals in Anhui Province, China, with an enrollment of 66 out of 111 solicited patients aged 16 to 74 years. Patients were recruited sequentially, by specific participating physicians at their clinic visits to three independent hospitals. The diseases in enrolled dental patients included dental caries, periodontal diseases and dental trauma. Renal diseases in recruits included kidney infections, stones and some other conditions. Patients were randomly assigned to receive the "2-minute sciatic nerve press" or the "placebo press". For the "2-minute sciatic nerve press", pressure was applied simultaneously to the sciatic nerves at the back of the thighs, using the fists while patients lay prone. For the "placebo press", pressure was applied simultaneously to a parallel spot on the front of the thighs, using the fists while patients lay supine. Each fist applied a pressure of 11 to 20 kg for 2 minutes, after which, patients arose to rate pain.</p> <p>Results</p> <p>The "2-minute sciatic nerve press" produced greater pain relief than the "placebo press". Within the first 10 minutes after sciatic pressure, immediate pain relief ratings averaged 66.4% (p < 0.001) for the dental patients, versus pain relief of 20% for the placebo press, and, 52.2% (p < 0.01) for the renal patients, versus relief of 14% for the placebo press, in median. The method worked excellently for dental caries and periodontal diseases, but poorly for dental trauma. Forty percent of renal patients with renal colic did not report any pain relief after the treatment.</p> <p>Conclusion</p> <p>Two minutes of pressure on both sciatic nerves can produce immediate significant conduction analgesia, providing a convenient, safe and powerful way to overcome clinical pain brought on by dental diseases and renal diseases for short term purposes.</p> <p>Trial registration</p> <p>ACTR 12606000439549</p

STIMULATION CHARACTERISTICS, COMPLICATIONS, AND EFFICACY OF SPINAL-CORD STIMULATION SYSTEMS IN PATIENTS WITH REFRACTORY ANGINA - A PROSPECTIVE FEASIBILITY STUDY

Objectives: In a prospective study with a 1-year follow-up we evaluated: (1) the feasibility of a method for the adjustment of spinal cord stimulator (SCS) parameters, (2) complications of SCS, and (3) efficacy of SCS. Methods: In patients receiving an SCS for severe angina unresponsive to standard therapies, SCS characteristics were evaluated within 1 week and at 4, 14, 26, and 52 weeks after SCS treatment. Step-by-step adjustment of pulse output parameters was performed at the electrode configuration at which paresthesias occurred (''sensory threshold''), covered the anginal area (''adjusted setting''), or provoked pain (''motor threshold''). In addition, the number of anginal attacks and intake of glyceryl trinitrate (GTN) tablets were recorded at regular intervals. Results: Twenty-two patients with either a bipolar (14) or a unipolar (8) system were evaluated. In the 14 patients with bipolar systems, alteration in paresthesias required 26 reprogrammings of the configuration. in the eight patients with bipolar systems who completed the followup without lead dislocation, the mean ''sensory threshold'' was 3.3 V (1.7-5.6), the mean ''adjusted stimulation'' output was 4.5 V (2.8-7.6), and the mean ''motor threshold'' was 4.9 V (2.8-7.7) after 4 weeks SCS. The mean stimulation duration per 24 hours was 14.2% (5%-24%), and the mean standardized impedance was 821 Omega (748-893) after 4 weeks SCS. The unipolar group demonstrated comparable results. After 1-year follow-up the parameters had not changed significantly. During the I-year followup, 6 of 22 patients experienced lead dislocation that required surgery. In all patients, anginal attacks (P <0.003) and GTN intake (P <0.005) were reduced significantly with SCS. The effect lasted during the 1 year. Conclusions: During a 1-year follow-up, the stimulation parameters did not change significantly in the 16 patients without lead dislocations. Our standardized method appears to be feasible for followup of SCS. Moreover, SCS seems to be an effective adjuvant therapy for intractable angina, despite a relatively frequent dislocation of the electrode