Transvenous tined electrode systems. An approach to acute dislodgement

Electrode complications, particularly dislodgement, significantly affect the outcome of pacemaker systems. One approach to the problem is the development of tined endocardial leads. Data from 50 consecutive patients receiving tined leads (Medtronic 6962) were evaluated and compared with data from 48 patients receiving flange-tipped electrodes (Medtronic 6901). Acute mean stimulation thresholds were 0.43±0.14 V and 0.78±0.24 mA with tined leads and 0.63±1.7 V and 1.01±0.36 mA with flange-tipped electrodes (P=0.001). Lead impedance was significantly lower with tined leads (521±77 Ω) than with flange-tipped electrodes (598±103 Ω) (P=0.001). R-wave sensing was not significantly different between the two types of leads. In the patients receiving tined leads, no pacing failures or other signs of acute dislodgement of leads occurred during the first 30 days, whereas 21% of the patients with flange-tipped electrodes required remanipulation or change in the electrode system because of dislodgement during a similar follow-up period (P<0.01). The tined electrode offers a signifcant improvement in leads systems by substantially reducing the rate of dislodgement and the stimulation threshold. It may be particularly beneficial in patients with tricuspid insufficiency or dilated, poorly contractile right ventricles. Routine use may alleviate many acute problems, particularly dislodgement, and allow more rapid mobilization of patients and earlier dismissal from the hospital after implantation - benefits that would also reduce the cost of medical care.