[IāD LIKE TO SHOW THE RR INTERVALS IN BOTH STRIPS]
Type II 2nd degree SA and AV block are similar in that the duration of the pause is twice that of the preceding RR interval. However, in AV block the diagnosis is more apparent because the non-conducted P wave (arrow) is present during the pause. The upper strip shown here, demonstrating type II AV block, was shown earlier (page 8.1.19). The lower strip, showing type II SA block, is from the preceding page.