Purpose: To compare a bipolar LV lead with a side helix for active fixation (bipol) and a quadripolar LV lead with passive fixation (quad) concerning the electrical performance and the ability to achieve an optimal and stable position.
Methods:The bipol has a maximum lead body diameter of 3.9 Fr versus 5.3 Fr. for the quad. Sixty two consecutive patients (pts; mean age 72±11 years; 27% females) scheduled for CRT implantation were randomly assigned to the bipol (n=31) or to the quad (n=31). The LV ejection fraction was 26±6%. The LV lead was targeted to a vein concordant to the LV segment with latest mechanical contraction decided by preoperative radial strain echocardiography. A five segments LV model was used.
Results (table):Initial successful implantation was achieved in 31 pts. (100%) and 30 pts. (97%) in the bipol group and the quad group, respectively. In 1 pt. an alternative stiffer bipolar LV lead was implanted. In 3 patients LV lead dislodgement occurred, all in the active fixated group.
Conclusions:The target placement was attained with both the bipol and the quad in the majority of pts. At follow up the pacing capture thresholds were low and stable with no significant difference between the two leads. Active fixation did not facilitate a more proximal position to the stimulating electrode.