Passive Pacing Lead Parameters Follow-up Analysis

Background:Cardiac pacing lead is always the weakest aspect of the cardiac pacing therapy,the advances concerning the functionality,size,and longevity of cardiac pacemakers depend on concomitant advances in cardiac pacing leads.The current state of affairs of cardiac pacing leads are focusing on excellent electrical properties and histocompatibility.High impedance,small diameter and steroid-eluting leads are the common choices in clinical practice.Objective:To evaluate and compare the steroid-eluting leads from different companies implanted in the past two years at Peking Union Medical College Hospital.Method:Three different brands of steroid-eluting leads were randomly selected and implanted in 91 patients from Nov,2005 to Apr,2008,which include 83 atrial leads and 85 ventricular leads.Patients were followed at 3 and 12 months after implantation.Pacing and sensing thresholds and lead impedance were measured at the time of implantation and each follow-up.All the records were analyzed retrospectively and compared.Results:At the first 3 months follow-up after implantation,atrial pacing thresholds revealed no significant difference(P＞0.05) in all brands of leads, compared to the records at the time of implantation.Biotronik atrial sensing thresholds reduced from 3.70±1.46 mV to 2.44±0.30 mV(P=0.001),while Ela and Medtronic showed no significant differences(P＞0.05).Biotronik ventricular pacing thresholds risen from 0.35±0.13 V to 0.17±0.23 V(P=0.003),Ela ventricular pacing thresholds risen from 0.58±0.24 V to 0.89±0.25 V (P＜0.001),but Medtronic revealed no significant differences(P＞0.05). Biontronik ventricular sensing thresholds risen from 9.74±1.93 mV to 14.6± 5.50 mV(P=0.015),Medtronic ventricular sensing thresholds risen from 11.29±4.38 mV to 15.42±5.43 mV(P=0.010),however,Ela remains no change statistically(P＞0.05).Compared to the records at the time of implantation,all the leads showed no significant difference in atrial pacing and sensing thresholds as well as ventricular sensing thresholds 12 months after implantation(P＞0.05).Biotronik ventricular pacing thresholds risen from 0.44±0.21V to 0.63±0.28 V(P=0.035),Medtronic ventricular pacing thresholds risen from 0.48±0.26 V to 0.78±0.33V(P=0.031),while Ela revealed no significant changes(P＞0.05).One patient suffered from lead dislocation but no other complications were identified during the follow-up.Conclusion:The three different kinds of steroid-eluting leads evaluated in this study revealed stable parameter variation with a reliable clinical effect.