Sinus bradycardia with first degree AV block
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Sinus bradycardia is evident from the long RR interval of 1280 msec, corresponding to a heart rate of 47 per minute. PR interval is also prolonged at about 320 msec. The combination can occur in vagotonic states or in those on beta blockers or other drugs which suppress both the sinus node and the AV node. Pure sinus node inhibitors like ivabradine cannot produce this combination. This combination is also often seen with acute inferior wall myocardial infarction.