Prystowsky E N, Naccarelli G V, Jackman W M, Rinkenberger R L, Heger J J, Zipes D P
Am J Cardiol. 1983 Jan 1;51(1):96-100. doi: 10.1016/s0002-9149(83)80018-6.
The purpose of this study was to determine the effects of enhanced vagal tone on human right atrial refractoriness in 12 patients. A specially built neck collar connected to a vacuum source was placed around the patient's neck and enhanced vagal tone was produced during neck suction using intracollar negative pressures of 50 to 60 mm Hg. Refractory periods were determined with a catheter electrode positioned in the high right atrium near the sinus node. Induced neck suction increased the spontaneous sinus cycle length from 837 +/- 96 to 1.136 +/- 273 ms (p less than 0.001) and shortened the atrial effective refractory period from 241 +/- 24 to 230 +/- 20 ms (p less than 0.01) and the atrial functional refractory period from 272 +/- 32 to 262 +/- 29 ms (p less than 0.01). In 2 of 2 patients, collar-induced decreases in atrial refractoriness and increases in spontaneous cycle length were prevented after atropine (0.03 mg/kg) was given intravenously. It is concluded that enhanced vagal tone mediated through muscarinic receptors shortens atrial refractory periods in man.
本研究的目的是确定增强迷走神经张力对12例患者右心房不应期的影响。将一个连接到真空源的特制项圈套在患者颈部，在颈部抽吸过程中，通过项圈内50至60毫米汞柱的负压产生增强的迷走神经张力。使用置于窦房结附近高位右心房的导管电极测定不应期。诱导颈部抽吸使窦性自发周期长度从837±96毫秒增加到1136±273毫秒（p<0.001），并使心房有效不应期从241±24毫秒缩短至230±20毫秒（p<0.01），心房功能不应期从272±32毫秒缩短至262±29毫秒（p<0.01）。在2例患者中，静脉注射阿托品（0.03毫克/千克）后，项圈诱导的心房不应期缩短和自发周期长度增加得到预防。得出的结论是，通过毒蕈碱受体介导的增强迷走神经张力可缩短人的心房不应期。
