PERMANENT implantable endocardiac pacemaker systems have greatly extended the surgical treatment of heart-block. Patients judged to be unfit for thoracotomy may now be offered substantial symptomatic relief with a relatively lowrisk operation employing local anesthesia. Early in the clinical experience of permanent endocardiac pacing, one expected electrode dislodgement, intermittent contact of the electrode due to myocardial contraction, rising myocardial impedance to electrode stimulation, predisposition to thrombosis by the large intravascular foreign body electrode, and possibly tricuspid insufficiency.
Prior to treating the two patients described in this report, we had encountered only dislodgement and intermittent contact of the bipolar electrode. These complications have been uncommon and have been noted early in the postoperative period. They have been easily remedied by further manipulation through the same incisions, with the patient under local anesthesia.
Recently, we have seen two patients who presented with vigorous diaphragmatic contractions noted approximately six weeks and four months
Palmer TE, Finestone AJ, Leary J. Endocardiac Pacemaker-Induced Diaphragmatic Contractions. JAMA. 1967;200(13):1179-1180. doi:10.1001/jama.1967.03120260075017