七、诊断多条副束 多条副束并存时,可利用其前向不应期的不同而用食道心房调搏检出.分级递增起搏,连续渐增起搏或S_1S_2扫描等方法均可使用。例如,在不同的起搏频率或不同配对间期的S_1S_2刺激时如出现两组以上形态不同的WPW预激图形则提示有两条以上房室副束存在。若房束副束与房室副束并存,而前者的不 Seven, the diagnosis of a number of side-by-side co-bundles coexist, can be used before the refractory period of esophageal atrial pacing can be used to detect different graded ascending pacing, progressive pacing or S_1S_2 scan and other methods use. For example, two or more groups of WPW pre-excitation patterns at different pacing frequencies or different pairs of S_1S_2 stimuli may indicate the presence of more than two AVs. If the beam and vice atrioventricular bundle coexist, while the former is not