ATRIAL-PACING LEADS FOLLOWING OPEN-HEART-SURGERY - ACTIVE OR PASSIVE FIXATION

The right atrial appendage is often amputated at the time of cardiopul monary bypass. Because of concerns regarding lead displacement, use of active fixation atrial leads has been recommended in patients who req uire permanent atrial or dual chamber pacing after open heart surgery. We evaluated the acute and chronic performance of active and passive fixation atrial leads implanted at our institution between 1985 and 19 93 in patients with previous open heart surgery. Of 78 consecutive pat ients, 38 had an active fixation atrial lead, 28 had a passive fixatio n steroid-eluting lead, and 12 had a passive fixation lead without ste roid-eluting properties. At implantation, sensed P wave amplitudes wer e similar in the three groups, but lead impedance and threshold were s ignificantly higher for active fixation leads compared to all passive fixation leads. During follow-up, atrial pacing thresholds were signif icantly higher, and sensed P wave amplitudes significantly lower, in t he patients with active fixation leads compared to those with passive fixation leads. Loss of sensing occurred in 6 of 38 (16%) patients wit h active fixation leads and 1 of 40 (2.5%) patients with a passive fix ation lead (P = 0.027). Atrial lead displacement occurred in two patie nts with active fixation leads and one with a passive fixation lead. C omparison with a parallel group of patients without previous open hear t surgery demonstrated that atrial lead performance was similar in the two groups. We conclude that, when permanent atrial or dual chamber p acing is necessary in patients with prior open heart surgery, it is ap propriate to implant a passive fixation atrial lead except on the infr equent occasions when a stable atrial position cannot be obtained.