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The perioperative risk for patients with pacemakers or implanted cardioverter/defibrillators (ICD) is mainly dependent on the underlying disease. However, severe to life-threatening complications of the implanted system can occur due to electromagnetic interference in the environment of the operation. These complications can be prevented or adequately treated by taking special precautions and measures. Even though the currently available data on the optimal perioperative management to pacemakers and ICDs is still unsatisfactory, the increasing clinical relevance of this topic was the reason for the formulation of recommendations by an interdisciplinary working group in Austria.

Pacing threshold is not a stable value during the pacemaker's life. It is affected by many physiological, pharmacological and pathophysiological factors. A pacing system able to confirm capture and automatically adjust its output to the actual pacing threshold is highly desirable for a prolonged battery life and maximal patient safety. The Autocapture(TM) of St. Jude Medical and the Capture Management(TM) of Medtronic are currently available on the market. The key feature is the measurement of the evoked response (ER) signal by the pacemaker for capture confirmation. In case of loss of capture, the Autocapture(TM) System delivers a back up safety pulse of 4.5 Volt and 0.49 ms and starts a new threshold search. The pacemaker adapts its output to 0.3V/0.25V above the newly measured threshold. This system needs bipolar leads with low polarization for the first generation in Microny® and Regency® pacemakers; in the second generation with Affinity® and Integrity® pacemakers various bipolar leads are suitable. The Capture Management(TM) System of Medtronic, available in the Kappa® DR 700 series, performs a two point automatic threshold search once every day during rest. The output is determined by the programmed safety margin (nominal 1.5×voltage threshold). A backup pulse is only delivered during the threshold search. No special electrodes are necessary.    These functions were shown to work safely and efficaciously in multicenter trials to decrease the current consumption with a prolongation of battery life up to 142%. The patients safety was increased by identifying changes of the capture threshold over time and adjusting the pacing stimulus. The conventional safety margins of 100% might not be safe for all patients. We also learned much about lead maturation and lead instability by the possibility of continuous follow-up of threshold changes in a larger group of leads in order to identify the risk group of about 10% of patients with late threshold increase and lead instability.

The grounds for liability with robotic surgery include damage to patients, causality, illegality and guilt. The patient must receive very comprehensive information on the treatment under consideration, his/her risk and what will be done in the case of technical failure. The surgeon operating the robotic device is obliged to provide normal conscientious care and state-of-the-art treatment. In addition, there is possible neglect of supervisory duties vis-à-vis other hospital personnel to be considered. A special problem is posed by a forensic physician who lacks experience in robotic surgery. There should be a surgeon at the operating table who is at least equally skilled as the surgeon operating the monitor. Robotic surgery must ultimately be at least as effective as conventional surgery, if not better. It must, however, be borne in mind that in cases involving this new technology, it is that patient who is the pioneer.

From 1990 to 1999, 2,853 ventricular and 1,084 atrial bipolar leads of various manufacturers (Medtronic, Biotronik, Vitatron, Ela, Pacesetter and Stöckert) were implanted during first implantations of pacemakers at the University of Graz, Dept. of Cardiac Surgery. Surgical complications with the need of reintervention were analyzed during a follow up period of up to 10 years. The overall lead-related complication rate for ventricular bipolar leads was 6.5% (187 of 2,853) and 5.3% (58 of 1,084) for atrial bipolar leads. Early complications within the first month were higher in the atrium (5.3% versus 2.2% in the ventricle), primarily due to dislocation, late complications were higher in the ventricle (4.3% versus 2% in the atrium) due to insulation problems and lead fracture. Insulation material had a marked influence with a higher failure rate in some leads with polyurethane insulation compared with silicone. Therefore we recommend a close follow-up of bipolar polyurethane leads by measurement of chronic impedance in order to assess insulation problems as early as possible.

The original Fontan operation was employed for patients with tricuspid atresia, but its application has been extended to a broad spectrum of congenital cardiac defects with a functional or anatomical single ventricle. From 1989 to 1995, 35 patients (23 males, 12 females) underwent a modified Fontan procedure; their age ranged from 14 months to 15 years (mean 5.1 a). Indications for operation were the following: D(S)ILV = 16, TA = 9, MA = 3, TGA with straddling AV-valve = 2, DORV = 4 and criss-cross heart = 1. The same surgical technique was utilized in all patients with redirection of the systemic venous return by means of a bidirectional cavopulmonary anastomosis and an intraatrial baffle, adaptable to all the various forms of underlying anatomy. Associated anomalies such as dextrocardia, coarctation, anomalous systemic or pulmonary venous return, subaortic stenosis and situs anomalies were present in 26%, 9%, 26%, 9%, and 20%, respectively. 12 patients were presumed to be at high risk and underwent a two-stage procedure (n = 7 bidirectional Glenn preceding the definitive repair and n = 5 a fenestration of the intraatrial baffle). Risk factors in our group of patients were: age under 2 years, abnormal systemic venous drainage, stenotic pulmonary arteries, PVR over 2 Wood units, mPAP over 15 mmHg, AV-valve incompetence, subaortic obstruction and ventricular dysfunction. Two patients had failure of the total cavo-pulmonary connection necessitating the take-down to a bidirectional Glenn anastomosis in the early postoperative period, with one death. Hospital mortality was 24% (n = 8). One child did not survive complications following the fenestration closure 4 months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)