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Implantation of a transvenous device in patients with a tricuspid valve replacement or a complex congenital heart disease with no access to the right ventricle represents problems. The lack of access to the right ventricle might preclude transvenous placement of a defibrillation lead at ICD implantation. A young patient (21 years) with a history of severe chest trauma with rupture of the tricuspid valve as well as the right coronary artery and consecutive inferior myocardial infarction was initially treated with tricuspid valve replacement (St Jude Medical artificial prosthesis, 33 mm) and a bypass graft to the right coronary artery. Four years later, the patient was admitted with a hemodynamically not tolerated ventricular tachycardia (VT: CL 250 ms, LBBB, left axis). The VT could be reproduced during electrophysiological testing. An ICD was implanted subpectorally in combination with a transvenous active fixation ICD lead. The transvenous ICD lead was placed via a guiding catheter into a coronary sinus branch (middle cardiac vein). Acceptable pacing and sensing values could be obtained. The defibrillation threshold was 25 J. In conclusion transvenous ICD lead implantation into a side branch of the coronary sinus in combination with a pectorally implanted "active can" ICD device seems to be an alternative approach. This approach may avoid implantation of additional subcutaneous defibrillation leads or even thoracotomy for ICD implantation.

About three years ago, the German Government initiated a complete change in the reimbursement system for costs of the in-hospital treatment of patients. A commission of representatives from every component of the German health system decided to adapt the Australian refined Diagnosis Related Groups (AR-DRG system). The AR-DRG system was selected as it would fit best to the German system and because of its high flexibility and preciseness reflecting severity of diseases and treatments. In October 2002, the first German Diagnosis Related Groups (G-DRGs) were calculated from the data of about 116 hospitals. These data now allow first analyses in how far a correct and precise grouping of patients in specific hospital settings is indeed performed and corresponds to the actual costs. Thus, we thoroughly calculated all costs for material and personnel during the in-hospital stay for each patient discharged during the first 4 months of 2002 from our cardiological department. After performing the grouping procedure for each patient, we analyzed in how far inhomogeneous patient distribution in the DRGs occurred and which impact this had on costs and potential reimbursements. Several different problems were identified which should be outlined in this work regarding three G-DRGs: costs of patients who received an implantable cardioverter defibrillator (F01Z) were markedly influenced by multimorbidity and additional expensive interventions which were not reflected by this G-DRG. Use of numerous catheters and expensive drugs represented a major factor for costs in patients with coronary angioplasty in acute myocardial infarction (F10Z) but seemed to be not sufficiently included in the cost weight. A specific area of patient management in our department is high frequency ablation of tachyarrhythmias which is included in other percutaneous interventions (F19Z). Complex procedures such as ablation of ventricular tachycardia or new innovative procedures as ablation of atrial fibrillation were associated with high costs leading to inadequate reimbursement. Furthermore, problems in the associated codes for diseases and procedures became apparent. Opportunities for future optimization such as specific new DRGs, splitting of DRGs, or the impact of changes in reimbursement for high-outliers were discussed.

The high incidence of inappropriate therapies due to supraventricular tachycardia remains a major unsolved problem of the implantable cardioverter defibrillator. A new morphology discrimination (MD) algorithm has been introduced to improve specificity of ICD therapy without loss of sensitivity. It was the aim of this study to systematically analyze sensitivity and specificity of the MD criterion in combination with the enhanced detection criteria sudden onset and rate stability in the detection of ventricular and supraventricular tachycardia. After ICD implantation in 259 patients, 787 detected episodes in 74 patients with available stored electrograms were documented during a follow-up period of 359 +/- 214 days. With a nominal programming of the MD algorithm at > or = 60%, sensitivity and specificity for all episodes were 82.6%/77.2%. For sinus tachycardia, atrial fibrillation and atrial flutter the specificities were 80.6%, 69.6% and 75%, respectively. In patients with primarily appropriate MD detection, sensitivity and specificity significantly improved to 95.8%/91.7%. Programming the sudden onset criterion with < 100 ms and the stability criterion with < 50 ms, sensitivity and stability of the combined application of the MD algorithm and sudden onset and MD algorithm and stability were 96.2%/52.2% and 94.4%/63.8%, respectively. The MD criterion in combination with other enhanced detection criteria might significantly improve specificity of tachyarrythmia detection of ICD therapy.

Sudden death accounts for a significant proportion of all death in patients with heart failure. Of currently available therapy, amiodarone and the implantable defibrillator (ICD) appear to have the greatest potential to reduce sudden death in heart failure. In this paper, the currently available information on the relative role of amiodarone and implantable defibrillators (ICD) in heart failure is reviewed.

Postoperative tests of implantable cardioverter defibrillators (ICDs) are routinely performed to ensure appropriate defibrillation by the device. However, efficacy and complications of this procedure are unknown. To scrutinize the currently accepted indications to test the defibrillation function of the ICD we retrospectively analyzed 844 ICD-tests in 439 ICD-systems and 409 patients. 755 ICD-tests (89.4%) were routinely performed (57% before discharge and 43% during follow-up); 58 tests (6.9%) were performed after a change of the antiarrhythmic drug regimen, 24 tests (2.9%) after a revision of a part of the ICD-system, and seven tests (0.8%) because of a suspected dysfunction of the ICD. During routine-tests six ICD-systems (0.8%) failed to defibrillate the patient. However, in all but one test abnormalities of the ICD-system had been observed before the test. After addition of antiarrhythmic drugs, three of 58 ICD-systems (5.2%) failed to defibrillate the patient during the test (amiodarone: n = 2, flecainide: n = 1). Four of seven ICD-systems (57%) tested due to a suspected dysfunction failed to defibrillate the patient. After revisions of parts of the ICD-systems, ICD-tests never revealed a failure of defibrillation. During 16 ICD-tests (1.9%) complications occurred. The most frequent complications was inappropriate shocks (n = 10; 1.2%), the most severe one (transient) neurologic symptoms (n = 4; 0.48%). Our experience demonstrates that postoperative tests of the defibrillation function of ICDs rarely reveal ICD-dysfunction. As testing is unpleasant for the patient and not free of complications, tests might be restricted to those patients in whom an ICD-dysfunction is suspected (based on clinical presentation, results of chest-x-ray, testing of sensing signal and stimulation threshold) or class I or class III antiarrhythmic drugs have been added to the antiarrhythmic drug regimen.

Patients with implantable cardioverter defibrillators (ICD) often suffer inappropriate ICD-therapies. The incidence, causes and risk factors of ICD-therapies for a rhythm other than ventricular tachyarrhythmias (VT) were determined retrospectively in 462 consecutive patients (pts). Inappropriate ICD-therapies were identified based on stored R-R intervals and/or electrograms. Eighty-two pts (18%) had inappropriate ICD-therapies. Actuarial rates for inappropriate ICD-therapies were 13%, 20%, 24% and 29% at 1, 2, 3 and 4 years after ICD-implantation, respectively. Atrial fibrillation with rapid ventricular response was the most common cause (34 pts, 39%). In 26 pts (30%), sinus tachycardia triggered inappropriate ICD-therapies, in 21 pts (24%) overseeing, mostly due to fractures and insulation failures of the leads, in three pts atrial flutter, in two pts non-sustained VT, in one pt supra-ventricular tachycardia and in another pt T-wave double sensing caused inappropriate ICD-therapies. In order to prevent recurrences of inappropriate ICD-therapies due to atrial fibrillation or sinus tachycardia, a rate stability (n = 19) or onset (n = 15) criterion was programmed, 41 pts additionally received beta-blocking agents and/or digoxin. In pts with overseeing an operative revision of lead system was performed. During further follow-up (15 +/- 13 months), 15 pts had recurrences of inappropriate ICD-therapies (eight pts due to atrial fibrillation, three due to sinus tachycardia and four due to overseeing). On multivariate analysis (Cox regression), history of atrial fibrillation, maximum heart rate during exercise and low cut-off rate for VT-detection were predictors of inappropriate ICD-therapies. Thus, inappropriate ICD-therapies are frequent, especially in the first year after implantation. Additional detection criteria, beta-blocking agents and/or digoxin prevent recurrences in most patients. In patients with a history of atrial fibrillation, high heart rate during exercise or a low cut-off rate for VT-detection, activation of additional detection criteria should be considered directly after ICD-implantation.

Treatment strategies in patients with life-threatening ventricular tachyarrhythmias (i.e. sustained ventricular tachycardia, ventricular fibrillation, aborted sudden cardiac death) are changing. Amiodarone and d,l-sotalol, chosen by electrophysiologic study guidance, can be considered as drugs of choice for the pharmacological treatment. Compared to these agents, which both have additional electrophysiologic effects, the new pure class III agents seem to be less effective. With regard to antiarrhythmic efficacy, clinical trials comparing the long-term efficacy of antiarrhythmic agents and the implantable cardioverter/defibrillator are under way. Preliminary results indicate that the implantable cardioverter/defibrillator may provide superior outcome with regard to sudden cardiac death compared to the use of class III agents.

Ultimately, implantable cardioverter-defibrillators (ICD) will one day be implantable like present pacemakers. However, due to the size of the pulse generator and the low defibrillation efficacy of monophasic shocks, only a few selected patients have been implanted transvenously-pectorally. Therefore, we have prospectively investigated whether a transvenous-pectoral approach is in general feasible with a new downsized ICD capable of delivering biphasic shocks. Out of 33 patients, 76% received a bipolar transvenous defibrillation lead system. In the first 13 consecutive patients, a randomized crossover study showed that this high efficacy was above all achieved by a superior defibrillation efficacy of the biphasic waveform in comparison to the monophasic waveform (69% vs. 23%; p = 0.03). Not a single patient could be defibrillated exclusively with the monophasic waveform. In a further 15 consecutive patients, a crossover study showed that a position of the transvenous anode within the Vena anonyma instead of the Vena cava superior is, in general, not superior (87% vs. 80%; p = 0.67). Only one patient could be exclusively defibrillated with the V. anonyma position. Intraoperatively, no complications occurred and all but one patient received a pectoral implantation of the pulse generator. Postoperatively, in five patients local complications related to the ICD system were seen; two needed a surgical revision. In two patients movements of the left shoulder joint were temporarily restricted. Thus, in the majority of patients a new downsized ICD capable of biphasic shocks can be implanted transvenously-pectorally like a pacemaker.

Technical improvements of third generation implantable cardioverter defibrillators (ICD) like antitachycardia pacing modalities lead to an extended use of ICDs, not only in patients with aborted sudden cardiac death, but also in patients with hemodynamically tolerable ventricular tachycardia. In addition, anticipated results of current prospective studies might indicate the prophylactic use of ICDs in patients with high risk for sudden cardiac death, but without documented ventricular tachyarrhythmias. This report reviews mortality and complications associated with the ICDs with epicardial defibrillation leads. Mortality is separated in cardiac death, sudden cardiac, arrhythmogenic "not so sudden" cardiac death, and overall mortality. Pulmonary complications and infections are related to the underlying disease and the surgical procedure. Device- and lead-related complications, high defibrillation thresholds, pacemaker interactions, inappropriate shocks, arrhythmic effects, syncope, and psychosocial problems are reported, respectively.

Unlabelled: To determine the effects and the underlying mechanisms of sudden rise of impedance during radiofrequency (RF) catheter ablation, 60 RF applications were delivered to isolated preparations of ventricular myocardium at three different power levels (mean: 3.7, 11.3, 19.3 watts). Pulse duration was 30 s, current voltage and catheter tip temperature were continuously monitored. Impedance rise occurred during 34 of 60 applications; the incidence of impedance rise increased at higher power levels. Impedance rise was significantly more often observed when the preparations were superfused with heparinized blood compared to saline solution (p less than 0.05). Catheter-tip temperature during radiofrequency application without impedance rise was significantly lower compared to applications with impedance rise (mean = 108 degrees C vs. 121 degrees C, p less than 0.01). The increase of catheter-tip temperature and maximal-tip temperature following impedance rise was significantly higher in blood when compared to saline solution (mean = +48 degrees C vs. +13 degrees C (p less than 0.001), Tmax: 121 degrees C vs. 245 degrees C). Following impedance rise, insulation defects of the electrode catheter and vaporized crater formation of the myocardium was often observed., Conclusions: During radiofrequency catheter ablation impedance rise occurs following overheating of the catheter electrode (greater than 110 degrees C). After impedance rise, catheter-tip temperature markedly increases. Insulation defects of the catheter and vaporized craters in the myocardium frequently occur after impedance rise. The results have important implications for the clinical use of RF-currents for catheter ablation; energy application should be immediately stopped after the occurrence of impedance rise.

We report two cases of licorice-induced arrhythmias. In both cases the ingestion of large amounts of licorice caused a marked hypokalemia. The importance of licorice-induced hypokalemia for the development of arrhythmias is underestimated from the small number of published cases. We conclude that patients with a predisposition for arrhythmias should avoid licorice candies.