The implantation of an ICD is the treatment of choice for patients (pts) with ventricular tachyarrhythmias (VF). To ensure correct functioning, VF is induced and ICD shocks are delivered at least twice intraoperatively. To determine the outcome and predictors of successful transvenous ventricular defibrillation, we retrospectively analysed pts and device characteristics, medication, and procedure related data of 240 ICD implantations from 201 pts (61 +/−16 yrs, 77% men). The 1st ICD shock successfully terminated VF in 191/240 (80%) cases, the 2nd shock in 182/191 (95%). There was no difference in pt and device characteristics or medication in respect to outcome. The cycle length of induced VF. (1st shock: 217+/−39vs.200+/−27ms; 2nd shock: 204+/−41vs.188+/−29ms) and the time between 1st and 2nd shock (424+/−400vs. 302+/−141s) tended to be shorter when defibrillation was unsuccessful. Fast ICD shock delivery (14.1vs.16.0s) and VF induction by t wave shock (92%vs.78%) were significantly associated with successful defibrillation. Transvenous ventricular defibrillation is highly successful intraoperatively. Possible predictors for success are induced VF cycle length, VF induction by t wave shock, duration of VF and time between 1st and 2nd shock delivery.

Review of available data suggests that serial drug testing in patients with a history of sustained ventricular tachyarrhythmias using various antiarrhythmic drugs including amiodarone is able to identify subgroups with favorable and unfavorable outcome (patient groups with suppression vs. no suppression of inducibility of VT/VF). These results more likely reflect patient selection rather than drug effects, thus limiting the role of electrophysiologically guided antiarrhythmic therapy to actively modify outcome. All major and actual antiarrhythmic drug trials including an amiodarone arm, have chosen to deliver this drug empirically in both patients with asymptomatic as well as severely symptomatic life-threatening sustained ventricular tachyarrhythmias instead of a guided approach. The empiric approach is therefore adequate until new valid data comparing the empiric with the guidedor the invasive with the non invasiveapproach tell us otherwise.

Im Rahmen operativer oder interventioneller Eingriffe können Interferenzen zwischen implantierbaren Cardioverter/Defibrillatoren (ICD) und Elektrokautern bzw. der Radiofrequenz-Katheterablation auftreten. Daraus können die Fehlabgabe von Stimulations- und Schocktherapien bzw. die Inaktivierung des ICDs resultieren und eine Gefährdung des Patienten darstellen. Methodik Wir untersuchten deshalb die intraoperativen Interaktionen bei 23 konsekutiven Patienten mit einem ICD (KHK n=15, DCM n=5, sonstige n=3, Alter 67±13Jahre) im Rahmen unterschiedlicher operativer und interventioneller Eingriffe. Es wurden 16 operative Eingriffe (allgemeinchirurgische OP n=7, urologische OP n=5, abdominelle OP n=2, gynäkologische OP n=1, Thorax-OP n=1) sowie 7 interventionelle Therapieverfahren (RF-Katheterablation n=5, ERCP mit Papillotomie n=2) durchgeführt. Die ausschließlich pektoral implantierten ICD-Systeme (Medtronic n=16, Guidant CPI n=7) bestanden aus 15 Einkammer- sowie 8 Zweikammer-Defibrillatoren. Präoperativ erfolgte eine Inaktivierung der ICD-Therapien, die Tachyarrhythmie-Detektion (VF 295±21ms, VT 370±55ms) der Aggregate wurde aktiv belassen (Überwachungsmodus). Die Position der intraoperativen, indifferenten Elektrode des Elektrokauters/RF-Generators wurde ermittelt (med. Oberschenkel rechts n=18, mittlere BWS dorsal n=5). Nach durchgeführtem Eingriff wurden der ICD-Speicher auf Detektionen bzw. die Programmierung auf Veränderungen überprüft sowie eine Funktionskontrolle durchgeführt. Ergebnis In keinem Fall kam es durch den Einsatz eines Elektrokauters oder durch eine RF-Ablation zu einer Fehldetektion durch den ICD oder zu einer Umprogrammierung. Schlussfolgerung Trotz der nicht nachweisbaren Interaktionen zwischen dem Einsatz von Radiofrequenzstrom und implantierbaren Defibrillatoren sollten ICDs präinterventionell inaktiviert werden, um eine maximale Patientensicherheit zu gewährleisten. Sollte sich jedoch diese Inaktivierung als ineffektiv oder als nicht kontrollierbar erweisen, so sind mit hoher Wahrscheinlichkeit keine Interferenzen zu befürchten. Auf jeden Fall sollte aber postinterventionell eine Funktionskontrolle des ICDs mit Überprüfung der Stimulations- und Sensingfunktion durchgeführt werden.

BACKGROUND During surgical and interventional procedures, interactions between implantable cardioverter defibrillators (ICD) and electrical cautery, respectively, application of radiofrequency (RF) energy may occur. Induction of inadequate shock therapies or device malfunction may result and represent a potential perioperative hazard for the patient. METHODS Hence, we analyzed the intraoperative interactions in 23 consecutive ICD patients with regard to different surgical and interventional procedures. Sixteen surgical operations (general surgery n = 7, urologic n = 5, abdominal n = 2, gynecological n = 1, thoracic n = 1) and 7 interventional therapies (RF catheter ablation n = 5, endoscopic papillotomy n = 2) were performed. The ICD devices were all located in the left pectoral position and consisted of 15 single and 8 dual chamber defibrillators. During the procedure tachyarrhythmia detection (VF 295 +/- 21 ms, VT 370 +/- 55 ms) of the devices was maintained active (monitoring mode); only ICD therapies were inactivated. The indifferent electrode of the electrical cauter/RF generator was placed in standard positions (right mid femoral position n = 18, thoracic spine area n = 5). After the procedure, the ICD memory was checked for detections, respectively, for changes of the programming. RESULT There was no misdetection or reprogramming of the ICD caused by electrical cautery or RF energy. CONCLUSIONS Despite the lack of undesired interactions ICDs should be inactivated preoperatively to assure maximum patient safety. However, should inactivation be ineffective or not manageable, electromagnetic interference is highly unlikely.

AIMS:Incisional atrial tachycardias in patients following surgery for congenital heart disease are based on complex structural abnormalities in these hearts. The aim of this study was to evaluate the use of the electroanatomical mapping system, CARTO, in consecutive patients with different forms of incisional atrial tachycardia.METHODS AND RESULTS:The electroanatomical mapping system combines electrophysiological and spatial information and allows visualization of atrial activation in a three-dimensional anatomical reconstruction of the atria. Electroanatomical mapping of right atrial activation was performed in 10 patients after surgery for congenital heart disease, surgery for Wolff-Parkinson-White syndrome, or heart transplantation presenting with 13 incisional atrial tachycardias. The three-dimensional mapping allowed a rapid distinction between focal (n=3) and reentrant mechanisms (n=10) and visualization of the activation wavefronts along anatomical and surgically created barriers. Electroanatomical activation maps (mean right atrial activation time 213+/-107 ms) were constructed with 89+/-60 catheter positions during an average mapping time of 48+/-33 min. Reentrant tachycardias propagating through the tricuspid annulus-vena cava inferior isthmus (n=6) or along periatriotomy loops (n=4) were identified in eight patients. Ectopic atrial foci near surgical scars could be localized in three patients. Catheter ablation by creation of a lesion in a critical isthmus of conduction or by targeting the arrhythmogenic focus eliminated 11 of 13 incisional atrial tachycardias.CONCLUSION:Visualization of atrial activation in a three-dimensional reconstruction of the right atrium using the electroanatomical mapping system CARTO facilitates understanding of the mechanism and defines the reentrant circuits of incisional atrial tachycardias. This new method may improve the success rate of electrophysiologically guided and anatomically guided catheter ablation of incisional atrial tachycardias.

Hintergrund: Ventrikuläre Spätpotentiale sind eher bei Postinfarktpatienten mit rezidivierenden Kammertachykardien als solchen mit überlebtem, Kammerflimmern vorhanden. Möglicherweise unterliegt die Spätpotentialnachweisbarkeit tageszeitlichen Schwankungen.

BACKGROUND:Ventricular late potentials are found more readily in post-infarction patients who had sustained ventricular tachycardia than in those who survived ventricular fibrillation. Hypothetically, a daytime variability of late potentials might be responsible for this finding.METHOD:Therefore a conventional late potential analysis only performed once a day was compared to a late potential analysis in time and frequency domain repeatedly performed every hour in the Holter-ECG of 160 post-infarction patients (50 patients (= VT-group) with documented, sustained ventricular tachycardia (cycle-length > 230 ms), 50 patients (= VF-group) who survived, documented ventricular fibrillation and 60 patient, without ventricular arrhythmias (= O VT/VF-group)).RESULTS:The conventional analysis showed late potentials in time domain in 72% of the patients in the VT-group, in 40% of patients in the VF-group and in 20% of the patients in the O VT/VF-group. The Holter-ECG showed late potentials to be permanently present in frequency domain in 66% of the patients in the VT-group, in only 6% in the patients in the VF-group and in no patient in the O VT/VF-group. However, in at least one analysis we detected late potentials in 84% of patients of the VF-group, in 90% of patients in the VT-group and in 18% of patients in the O VT/VF-group. Transiently detectable late potentials in patients of the VF-group were predominantly seen at heart rate accelerations in the morning hours, ST-segment shifts or transitory decreased heart rate variability.CONCLUSIONS:Post-infarction patients with sustained ventricular tachycardia predominantly have constantly detectable late potentials over 24 hours. In these patients conventional late potential is successful for post-infarction risk stratification at any time of the day. However, in post-infarction patients who survived ventricular fibrillation, late potentials are found to be transitory and only detectable by Holter-ECG. Thus, late potential analysis performed in the Holter-ECG might improve post-infarction risk stratification in patients prone to sudden cardiac death.

AIMSAntiarrhythmic drug treatment for atrial fibrillation can cause atrial flutter-like arrhythmias. The aim of this study was to clarify the effect of catheter ablation of the tricuspid annulus-vena cava inferior isthmus on amiodarone-induced atrial flutter and to determine the incidence of atrial fibrillation after catheter ablation of amiodarone-induced atrial flutter in comparison to regular typical flutter.METHODS AND RESULTSAmong 92 consecutive patients with typical atrial flutter who underwent isthmus ablation 28 patients had atrial flutter without a history of previous atrial fibrillation (group I), 10 patients had atrial flutter following the initiation of amiodarone therapy for paroxysmal atrial fibrillation (group II) and 54 patients had atrial flutter and atrial fibrillation (group III). Atrial cycle length during atrial flutter in amiodarone-treated patients (group II) (277+/-24 ms) was significantly longer as compared to the cycle length of atrial flutter in group I (247+/-33 ms) and group III patients (235+/-28 ms). The rate of successful transient entrainment and overdrive stimulation to sinus rhythm was not different between patients with (60%) or without amiodarone therapy (group I: 71%, group III: 53%). Successful isthmus ablation with bidirectional conduction block eliminating right atrial flutter was achieved in 90% of amiodarone-treated patients and 93% of patients without amiodarone therapy. In the amiodarone-treated patient group atrial conduction times during pacing in sinus rhythm were significantly prolonged by 20-30% before and after ablation in all regions of the reentrant circuit. During a mean follow-up of 8+/-3 months post-ablation, atrial fibrillation recurred in two of 10 patients on continued amiodarone therapy after successful isthmus ablation. Thus, successful catheter ablation of atrial flutter due to amiodarone therapy was associated with a markedly lower recurrence rate of paroxysmal atrial fibrillation (20%) as compared to patients with atrial flutter plus preexisting paroxysmal atrial fibrillation (76%) and was similar to the outcome of patients with successful atrial flutter ablation without preexisting atrial fibrillation (25%).CONCLUSIONThese data suggest that isthmus ablation with bidirectional block and continuation of amiodarone therapy is an effective therapy for the treatment of atrial flutter due to amiodarone therapy for paroxysmal atrial fibrillation.

A 72-year-old woman with complete situs inversus underwent successful slow pathway ablation of typical AV nodal reentrant tachycardia. Catheter ablation of AV nodal reentrant tachycardia in dextrocardia required a lengthy procedure but was safe and without complications.

UNLABELLED:Antitachycardia pacing techniques (ATP) have proved useful for termination of ventricular tachycardia (VT). However, little is known about the efficacy and safety off ATP during long-term follow-up in a larger study population. We analyzed the data of 80 ICD patients (pts) with spontaneous monormorphic VT, mean age 59 +/- 12 years, the mean follow-up was 26 +/- 17 months. 50 pts (62.5%) had coronary artery disease, 18 (22.5%) dilative cardiomyopathy (DCM), the remaining 12 pts (15%) had no or other cardiac diseases. 2926 episodes of ventricular tachycardia (cycle length 349 +/- 51 ms, 240-520 ms) occurred in 64/80 pts (80%), overall efficacy of ATP was 89.9%, acceleration occurred in 4.1% of VTs. Success of ATP did not correlate with positive ATP testing on induced arrhythmias, LVEF, NYHA class or aneurysm. Neither underlying heart disease nor antiarrhythmic medication had an impact on the ATP success rate. ATP efficacy was linked significantly to short VT cycle length (VTCL, 240-300 ms, p < 0.01) and long coupling intervals (91-97%), p < 0. 01). Acceleration occurred in 32% of pts and in 4.1% of VT episodes; it was also dependent on short VT cycle length (< 300 ms vs > 300 ms, p < 0.04) and short coupling intervals (< 81% vs >/= 81%, p = 0. 01). CONCLUSIONS:First, ATP is a highly effective therapy, independent of patients characteristics. Second, short VT cycle length and long ATP coupling intervals were identified as predictors for successful ATP. Best conversation rates were obtained with coupling intervals between 90 and 97% of VTCL in tachycardias with a cycle length < 300 ms. Third, testing ATP on induced VTs before hospital discharge did not improve efficacy, empiric modes showed equal success rates. Fourth, acceleration rate of ATP depends on VT cycle length and coupling interval; therefore, aggressive ATP modes should be carefully applied in patients with VTs faster than 300 ms.

Das Prinzip der antitachykarden Stimulation (ATS) ventrikulärer Tachykardien bei Patienten mit implantierbarem Cardioverter/Defibrillator (ICD) hat sich als effektive Option zur schmerzlosen Therapie monomorpher ventrikulärer Tachykardien (VT) etabliert. Ziel dieser Analyse war es, die Effizienz und Sicherheit dieser Therapieform an einem größeren Patientenkollektiv mit einer großen Anzahl spontaner VTs zu ermitteln, sowie Prädiktoren, die mit einer erfolgreichen Überstimulation assoziiert sind, zu identifizieren. Wir untersuchten 2926 Episoden spontaner monomorpher VTs mit einer mittleren Zykluslänge von 349 ± 51 ms (240–520 ms). Das Beobachtungskollektiv bestand aus 80 Patienten (KHK n = 50, dilatative Kardiomyopathie n = 18, sonstige n = 12), Alter 59 ± 12 Jahre, mittlere Nachbeobachtungszeit 26 ± 17 Monate. 64 Patienten (80%) erfuhren 2629 Episoden einer VT, die Erfolgsquote der ATS lag bei 89,9%. Der Erfolg war nicht mit einer effizienten Testung des Modus an induzierten Tachykardien, der Auswurffraktion, dem Grad der Herzinsuffizienz (NYHA) oder kardialen Aneurysmen assoziiert. Ebenso beeinflußten weder die Grunderkrankung noch Antiarrhythmika die ATS-Erfolgsrate. Als Prädiktoren für den Therapieerfolg konnten kurze VT-Zykluslängen (VTCL, ≤ 300 ms vs. > 300 ms, p < 0,01) und lange Kopplungsintervalle der Therapien (≥ 91% vs. < 91%, p < 0,01) identifiziert werden. Akzelerationen wurden bei 32% der Patienten und in 4,1% aller VT-Episoden beobachtet, signifikant häufiger bei kurzen VTCL (≤ 300 ms vs. > 300 ms, p < 0,04) und kurzen Kopplungsintervallen (≥ 81% vs. ≥ 81%, p < 0,01).

A68-year-old man presented with an incessant supraventricular tachycardia 3 months after heart transplantation. A dual-chamber pacemaker had been implanted immediately after surgery for bradyarrhythmias. Electrophysiological study was performed with a multipolar halo catheter (20 electrode pairs) in the right atrium and bi- or quadripolar catheters in a high lateral, His, and coronary sinus ostium position of the right atrium (Figure⇓, top right). An atrial reentrant …

Atrial tachycardia is a rare form of supraventricular tachycardia, accounting for about 10-15% of patients presenting to experienced arrhythmia centres for radiofrequency catheter ablation. The mechanism may be either focal due to increased or abnormal automaticity or triggered activity, or macro re-entrant. When incessant tachycardia is present, tachycardiomyopathy may develop.The efficacy of antiarrhythmic drugs for long-term management of atrial tachycardia is poorly defined, but is probably limited. Class IC or class I agents may be used in re-entrant atrial tachycardia, and verapamil, beta-blockers or class IC agents in the focal type. If these drugs fail, amiodarone may be tried.Experience with radiofrequency catheter ablation to cure atrial tachycardia is limited, but results are very promising with success rates between 80% and 95%, and an acceptably low recurrence and complication rate. Thus, it is likely that, with more experience, radiofrequency catheter ablation will become therapy of first choice for atrial tachycardia when this arrhythmia is not easily and effectively controlled by drugs.

Aims The aim of the study was to examine the results of implanting small sized cardioverter defibrillators in the pectoral as opposed to the abdominal area. Hitherto, owing to the large size of the early defibrillators, the site of implantation had been confined to the abdomen.Methods Between 30 March 1993 and 1 November 1994, 778 patients from 63 centres in 14 countries underwent their first device implantation. The study was set up to evaluate the safety and the efficacy of Medtronic models 7219 D, a multi-lead abdominal/pectoral implantable cardioverter defibrillator, and 7219 C, a pectoral single-lead Active Can(TM) implantable cardioverter defibrillator. There were 155 abdominal and 623 pectoral implants. Survival data were comparable during a mean follow-up period of 4.0 +/- 4.6 months, with no difference regarding the pectoral placement of single (n = 392) or multi-lead (n = 231) devices. The only significant difference was related to severe lead-related events: 5.3% in the pectoral vs 11.6% in the abdominal group (P<0.05). These events were mainly related to lead dislodgement. Kaplan-Meier estimates showed that both single and multilead systems, in either the pectoral or abdominal position, demonstrated a similar severe adverse event-free survival.Conclusion These findings suggest that an implantable cardioverter defibrillator (18 mm thick, 80 cc volume, 129 g weight) can be implanted in the pectoral position without an increase in clinically relevant adverse events compared to abdominal implantation. Pectoral implantation was associated with a significantly reduced lead-related severe adverse event rate.

Osseous metastases to the hand are very rare. Only a single case of osseous metastasis of hepatocellular carcinoma to the hand has been reported in the literature to date. We report a case of osteolytic metastasis of the right first metacarpal as first manifestation of unresectable, alpha-fetoprotein-negative hepatocellular carcinoma (pT3, Nx, M1, UICC stage IVB, Okuda's stage I). The therapy consisted of R0-resection and hormonal therapy with tamoxifen 2 x 10 mg/d orally. Generally patients with metastatic cancer to the bones of the hand have a very poor prognosis.