背景:血管迷走性晕厥(VVS)是晕厥的主要原因。最常见的机制是心脏抑制反应,血管抑制反应,或两者的混合物。消除或克服迷走神经张力影响的神经刺激可以用作VVS的治疗策略。
方法:研究了6只雄性犬。刺激(10-Hz,2ms脉冲持续时间,2分钟持续时间)的宫颈迷走神经(CV),胸迷走神经(电视),星状神经节(SG)使用针状电极在3V下进行,5V,和10V输出。在10V的输出下进行SG刺激,在相同的输出下进行TV刺激。心率(HR)血压(BP),和心输出量(CO)测量之前,during,刺激后。
结果:右颈部迷走神经刺激与显著的血流动力学变化相关。HR,SBP,DBP降低(107±16vs.78±15bpm[P<0.0001],116±24vs.107±28mmHg[P=0.002]和71±18vs.58±20mmHg[P<0.0001]),分别,而左宫颈迷走神经刺激变化最小。与TV刺激相比,CV刺激与更大的血液动力学变化相关。左和右SG刺激显着增加收缩压(SBP),舒张压(DBP),和HR在5V和10V,可以在刺激后30s内观察到。左SG和右SG刺激均观察到血液动力学参数的输出依赖性增加。在左和右SG刺激之间没有看到差异。SG刺激叠加显着增加HR,BP,和来自双侧基线迷走神经刺激的CO。
结论:星状神经节刺激导致HR和BP增加,尽管有明显的迷走神经刺激。这可以用于治疗血管迷走性晕厥。
BACKGROUND: Vasovagal syncope (VVS) is the leading cause of syncope. The most frequent mechanism is that of a cardioinhibitory response, vasodepressor response, or mixture of both. Neural stimulation that negates or overcomes the effects of vagal tone may be used as a treatment strategy for VVS.
METHODS: Six male canines were studied. Stimulation (10-Hz, 2 ms pulse duration, 2 min duration) of the cervical vagus (CV), thoracic vagus (TV), and stellate ganglia (SG) was performed using needle electrodes at 3 V, 5 V, and 10 V output. SG stimulation at an output of 10 V overlaying TV stimulation at the same output was performed. Heart rate (HR), blood pressure (BP), and cardiac output (CO) were measured before, during, and after stimulation.
RESULTS: Right cervical vagal stimulation was associated with significant hemodynamic changes. HR, SBP, and DBP were reduced (107 ± 16 vs. 78 ± 15 bpm [P < 0.0001], 116 ± 24 vs. 107 ± 28 mmHg [P = 0.002] and 71 ± 18 vs. 58 ± 20 mmHg [P < 0.0001]), respectively, while left cervical vagal stimulation had minimal changes. CV stimulation was associated with greater hemodynamic changes than TV stimulation. Left and right SG stimulation significantly increased systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR at 5 V and 10 V, which could be observed within 30 s after stimulation. An output-dependent increase in hemodynamic parameters was seen with both left and right SG stimulation. No difference between left and right SG stimulation was seen. SG stimulation overlay significantly increased HR, BP, and CO from baseline vagal stimulation bilaterally.
CONCLUSIONS: Stellate ganglia stimulation leads to increased HR and BP despite significant vagal stimulation. This may be exploited therapeutically in the management of vasovagal syncope.