[About some rare complications caused by transvenous pacemaker electrodes. Morphological and clinical findings (author's transl)].

Early and late dislocation of electrodes incl. perforation of myocardium and infections of pacemaker systems are the most frequent complications during endocardial pacing. Next functional disorders caused by a risen threshold for stimulation and sensing problems as well as pure technical defects have to be mentioned. The following rare complications were observed in three autopsies: 1. Electrode located in the vena cordis media. 2. Bipolar pacemaker electrode in unstable position near the atrioventricular boundary. 3. Infected transvenous pacemaker electrode migrated into the right vena iliaca externa. Letal thromboemboli sm of the pulmonary arteries. 4. Electrode fragment causing chronic cervical fistula. Consecutive death of the patient by bacterial endocarditis of the mitral valves. Some morphological and clinical aspects of these complications are discussed, the literature is reviewed. Special sight is kept on "trapped" electrodes and coincident infection. It is considered how to avoid those accidents.