[Experience with 208 "screw-in" type pacemaker leads with particular reference to atrial positioning (author's transl)].

In 190 patients, 208 "screw-in" type pacemaker leads were implanted; 147 in the right ventricle and 61 in the right atrium. There was no significant difference in the time required for atrial (54.7 +/- 19 min) or ventricular fixation (56.0 +/- 25 min). Similarly, fluoroscopy times for both atrial (6.3 +/- 4 min) and ventricular positioning (8.1 +/- 6 min) were equivalent. In the subsequent follow-up period ranging from one to 23 months, only one dislocation of a "screw-in" type atrial lead was seen, and that in a patient with "twiddler syndrome". Otherwise, in patients in whom the lead was securely implanted, no evidence of dislocation has been observed. In one patient "under-sensing" developed subsequent to repositioning for exit-block. In this patient population, the use of "screw-in" type electrodes, in particular through facilitation of atrial positioning, has substantially lessened the rate of pacemaker complications.