Abstract：ObjectiveTo investigate the electrocardiographic changes of dual atrioventricular node pathways revealed by unfixed PR interval on ambulatory electrocardiograph(AECG).MethodsRetrospective analysis was made on 44 patients with unfixed PR interval on AECG.ResultsAtypical seconddegree atrioventricular block Mobitz typeⅠphenomenon revealed a high incidence rate of dual atrioventricular node pathways, mainly occurring in the form of bradycardia and at night, premature ventricualr contraction taking the second place. ConclusionExcessive prolongation of PR interval caused by slow pathway conduction will influence the electrical and mechanical activity of heart or atrioventricular synchrony, and furtherly result in cardiac insufficiency in a long term. Therefore, the above phenomenon needs to be emphasized on an AECG report.
2014, Vol. 23 
