The Effects Of Different Basic Atrial Pacing Frequency On Atrioventricular Nodal Function

Objective Atrial pacing with different fundamental frequency measured at the atrioventricular nodal effective refractory period compared to evaluate the fundamental frequency of different atrial pacing on AV node conduction function. With the foundation and increase the frequency of atrial pacing was reduced atrioventricular node conduction is based on the frequency filtering effect of other physiological phenomena to explain. Atrial pacing at different frequencies can reveal atrioventricular node can not be present at a frequency of electrophysiological phenomena. Stimulated by the process of scanning S1S2 induced supraventricular tachycardia in value.Method 60 patients with supraventricular tachycardia in patients with cardiac electrophysiology examination and radiofrequency ablation, stimulation with atrial pacing pulse is issued after 8 S1S1 S2 pulse. Were given S1S2600/400ms, S1S2500/400ms, S1S2400/400ms pacing, S1S2 interval beginning from 400 ms to 10 ms reduced. Coronary sinus to stimulate the choice 9,10. Recorded under different pacing based on the frequency of atrial effective refractory period, atrioventricular node functional refractory period and effective refractory period, dual atrioventricular node pathways fast pathway and slow pathway effective refractory period. Tachycardia induced by (1) S1S1 method:This includes a short array to stimulate the rapid stimulation Gradually stimulating and so on. (2) atrial stimulation programs:Program to stimulate the S2 scanning. (3) ventricular programmed stimulation:atrial electrical stimulation fails to stimulate in the ventricle. If the above are not sufficient to induce tachycardia, given intravenous isoproterenol or atropine-induced tachycardia. The data were collected on SPSS13.0 software statistical package for data processing, measurement data of measured values mean±standard deviation between the two groups compared by t test among groups using ANOVA, with count dataχ2 test, correlation between the use of non-parametric spearman rank correlation analysis, (P<0.05)as statistically significant difference.Results 60 patients,40 patients were all three basic frequency of atrial effective refractory period data showed that blossoms gradually increase the frequency of house foundation, atrial effective refractory period shortened accordingly (P<0.05).22 patients received all three basic frequency of the atrioventricular node effective refractory period of the data. Xpress room base rate will increase, atrioventricular node effective refractory period extension (P＜0.05), atrioventricular nodal functional refractory period shortened (P<0.05). The subject program to stimulate the S1S2 pacing-induced atrioventricular reentrant tachycardia method success rate 97.18%, while the S1S1 pacing success rate of inducing only 67,61%. P= 0.001,The difference was statistically significant.Conclusion The atrial pacing rate of change can affect the AV node effective refractory period and conduction in refractory period. Xpress room base rate will increase, atrioventricular node effective refractory period extension (P<0.05), atrioventricular nodal functional refractory period shortened(P<0.05). The role of changes in sympathetic tone different. Read pacing frequency on the atrioventricular node Refractory period of analysis and assessment of physiological characteristics of arrhythmia is very important point. Reentrant tachycardia caused by the two paths should be the greater of the margin, the more wide-induced tachycardia in the window, the program to stimulate the S2 insert more matches between the two paths to each of the transmission delay and should not be on the match to create a continuous, electrical activity cycle. Therefore timely S2 ago thorn more effective than the rapid pacing-induced tachycardia. Therefore affect the bypass, atrioventricular node, atrioventricular node speed track should match the relationship of the factorsPacing cycle as the basis for adjustment, with atropine, isoproterenol and other drugs can increase atrioventricular reentrant tachycardia induced.