ABSTRACT
Objective To investigate the sensitivity and specificity of conventional 12 lead electrocardiogram(ECG)and 24h dynamic ECG in patients with pacemaker implantation.Methods From May 2016 to May 2017,65 patients with pacemaker implantation in Heji Hospital Affiliated to Changzhi Medical College were selected.All patients were examined by two methods of routine 12 lead ECG and 24h dynamic ECG.The arrhythmia detection results,as well as sensitivity,specificity,accuracy and other indicators were observed and compared in the two groups.Results The positive rate of arrhythmia detected by 24h dynamic ECG was 96.9％,which was higher than 53.8％of the 12 lead ECG,the difference was statistically significant(χ2 =5.182,P <0.05).The detection rates of atrioventricular block,premature ventricular premature beat and premature atrial premature beat in 24h dynamic ECG group were higher than those of routine 12 lead ECG group,the differences were statistically significant(χ2 =8.615,P<0.05).The monitoring specificity,sensitivity and accuracy of 24h dynamic ECG were 96.9％,95.4％and 95.4％,respectively,which were higher than those of the conventional 12 lead ECG(58.5％,61.5％and 53.8％),the differences were statistically significant(all P<0.05).Conclusion The detection rate of arrhythmia in patients with pacemaker implantation by 24 h Holter is higher than that of routine 12 lead ECG,and its accuracy,specificity and sensitivity are higher,and it is safe and reliable,it is worthy of popularizing in the clinic.
ABSTRACT
Objective To observe the 12-lead ECG ( electrocardiogram ) characteristics of Japanese rabbits , and provide basic ECG data for cardiovascular disease research .Methods The 12-lead ECG and X-rays of 55 male Japanese rabbits were recorded in supine position after intraperitoneal injection of 20% urethane.Results ECG:① The 12-lead ECG characteristics of male Japanese rabbits were similar to humans .The rabbit heart rate was 265.5 ±36.8 beats/min, faster than that of humans .No arrhythmia was found in all the 55 rabbits.② The supine position average ECG axis was between 19 °to 250 °, varying a lot .③P wave:The shape of P wave was blunt round or a little bit sharp .P waves were all in accordance with the sinus P wave rules , which were more obvious in lead II , aVF and all chest leads .④ The PR interval was 0.063 ±0.007 s.⑤The QRS duration was 0.040 ±0.005 s.The main waves were mostly upward in leadsⅡ,Ⅲ, and aVF .The same as humans , the R/S ratios were increased by degrees in chest leads .⑥The ST segment was short, and was located in the equipotential line .⑦ The shapes of T wave were mostly round , partly had twin peaks .T waves were more obvious in leads Ⅱ,Ⅲ, aVR, and AVF and chest leads .⑧The QT interval was 0.142 ±0.015 s, and QTc was 0.306 ±0.034 s.In the X-rays, most heart shadows were in the center and right chest .Conclusions The normal values of 12-lead ECG characteristics of Japanese rabbits are obtained in this study , which are of certain application value in experimental studies of cardiovascular diseases .