慢心律是疗效明显的第一型抗心律失常药物,抑制除极化作用的最大率,但是不影响静止电位;无抗交感活性;不延长动作电位期限或对抗钙内流;对于心房与房室结不应期无影响,希氏束相对性不应期缩短,窦率、房室结或希氏束传导时间不受影响。对于冲动失常或传导阻滞者可发生不一致的效 Slow heart rhythm is the first type of antiarrhythmic drug with obvious curative effect, which can inhibit the maximal rate of depolarization, but does not affect the resting potential; no anti-sympathetic activity; does not prolong the action potential duration or counteract the calcium influx; for the atria and atrioventricular Knot refractory no effect, His bundle relative refractory period shortening, sinus rate, atrioventricular node or His bundle conduction time is not affected. For impulsive or block can occur inconsistent effect