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ObjectiveAtrial fibrillation or atrial flutter (AF) and heart failure (HF) often go hand in hand and, in combination, lead to an increased risk of death compared with patients with just one of both entities. Sex-specific differences in patients with AF and HF are under-reported. Therefore, the aim of this study was to investigate sex-specific catheter ablation (CA) use and acute in-hospital outcomes in patients with AF and concomitant HF in a retrospective cohort study.MethodsUsing International Statistical Classification of Diseases and Related Health Problems and Operations and Procedures codes, administrative data of 75 hospitals from 2010 to 2018 were analysed to identify cases with AF and HF. Sex differences were compared for baseline characteristics, right and left atrial CA use, procedure-related adverse outcomes and in-hospital mortality.ResultsOf 54 645 analysed cases with AF and HF, 46.2% were women. Women were significantly older (75.4±9.5 vs 68.7±11.1 years, pConclusionsThere are sex differences in patients with AF and HF with respect to demographics, resource utilisation and in-hospital outcomes. This needs to be considered when treating women with AF and HF, especially for a sufficient patient informed decision making in clinical practice.

ECG criteria for identifying an epicardial origin of ventricular tachycardia (VT) have mainly been described for VTs with basal-superior and lateral origin. The aim of this study was to determine ECG criteria for epicardial VTs with anterior origin as a guide for trans-pericardial ablation. Among 22 patients undergoing successful ablation of VTs from the anterior myocardial wall, 14 patients underwent endocardial ablation and 8 patients underwent epicardial ablation. VTs with anterior origin ablated epicardially had widened QS complexes in precordial leads with staircase-shaped notching and slowing of the descent to the nadir of S. In comparison, endocardial VTs with anterior origin usually had narrower QS complexes with a smooth and fast downstroke to the nadir of S. The duration of the negative pseudodelta wave was longer in epicardial VTs (55 ± 12 ms) compared to endocardial VTs (22 ± 12 ms). The interval “time to the nadir of S” in patients with anterior VT origin was longer in epicardial VTs (121 ± 16 ms) than in endocardial VTs (80 ± 22 ms). The QRS duration was also longer in patients with epicardial origin (212 ± 19 ms) than with endocardial VT origin (166 ± 30 ms). Epicardial origin of VTs arising from the anterior myocardial wall produces a slowing, widening and staircase-shaped notching in the initial VT–QS complex. Thus, the morphology of the initial part of the QS complex in precordial leads can be used as a guide for trans-pericardial ablation of VTs with anterior origin.

Background: Intraoperative controlled mechanical ventilation (CMV) changes the intrathoracic geometry and may impact postoperative left ventricular (LV) lead function after CRT implantation. This multicenter study investigates the effect of intraoperative ventilation setting (spontaneous breathing[SB] vs CMV) on postoperative LV lead function taking into account patients' body mass index (BMI). Methods: CRT implantation was performed at two centers during SB in 92 and during CMV in 73 patients. Follow-up was carried out after 3 5 and 36 53 days. Functional lead parameters (FLP;pacing threshold and impedance), postoperative adverse events (A;phrenic nerve stimulation [PNS] and lead malfunction), and patients' BMI were assessed. Delta values of FLP between baseline and follow-up visits were analyzed applying an analysis of covariance model to detect subclinical alterations in LV lead function. Results: AE occurred in a total of 36 (21%) patients. PNS was observed in 26 (15%) patients and LV lead repositioning due to malfunction was necessary in 10 (6%) patients. Both AE and FLP delta values between baseline and follow-up were not associated with intraoperative ventilation settings nor the patients' BMI. Conclusions: This study demonstrates that there is no impact of the intraoperative ventilation setting (SB vs CMV) on postoperative FLP or the occurrence of AE. This is also the case taking into account the BMI. With respect to these findings both approachessedation only or general anaesthesia including CMVcan be safely implemented during CRT implantation.

Ventricular arrhythmias (VAs) from the left ventricular outflow tract (LVOT) can have multiple exits exhibiting divergent ECG features. In a series of 131 patients with VAs with LVOT origin, 10 patients presented with divergent QRS morphologies. Multisite endo- and epicardial mapping of different exit sites was performed. The earliest ventricular activity of 23 LVOT VAs in 10 patients was detected in the endocardium of the LV in 7 patients, the aortic sinuses of Valsalva (SoV) in 3 patients, the distal coronary sinus in 6 patients, the anterior interventricular vein in 3 patients, and the posterior right ventricular outflow tract (RVOT) in 4 patients. Simultaneous elimination of two divergent QRS morphologies of LVOT VAs by ablation from a single site was achieved in 5 patients (aorto-mitral continuity in 3 patients, SoV and RVOT in each 1 patient) using a mean maximum ablation energy of 46 ± 5 W. Sequential ablation from two or three different sites, including trans-pericardial and distal coronary sinus ablation in each 2 patients, led to elimination of the divergent VA QRS morphologies in the other 5 patients. During the follow-up of 28 ± 29 months, 4 of the 10 patients had recurrence of at least one LVOT VA. A 43-year-old patient with muscular dystrophy Curschmann-Steinert had recurrence of sustained LVOT VTs and died of sudden cardiac death. Multisite mapping of different exit sites of LVOT VAs can guide ablation of intramural foci but the recurrence rate after initially successful ablation was high.

Ein Makroreentry innerhalb des His-Purkinje-Systems kann zu einer anhaltenden ventrikularen Tachykardie (VT) fuhren, die als Bundle-Branch-Reentry-VT bezeichnet wird. Die Bundle-Branch-Reentry-VT ist i. d. R. mit einer Erkrankung des His-Purkinje-Systems und einer eingeschrankten linksventrikularen Funktion assoziiert. Im Fall der typischen Bundle-Branch-Reentry-VT wird der rechte Schenkel in anterograder Richtung aktiviert, und die ventrikulare Depolarisation beginnt am Ende des rechten Schenkels im ventrikularen Septum mit der Folge einer typischen Linksschenkelblock QRS-Morphologie. Bei Patienten mit schwerer linksventrikularer Dysfunktion und Beteiligung des rechten Ventrikels werden aber auch atypische Oberflachen-EKG-Befunde beobachtet, welche die Diagnose einer Bundle-Branch-Reentry-VT erschweren konnen. Die Diagnose einer Bundle-Branch-Reentry-VT ist von groser Bedeutung, da bei Patienten mit Bundle-Branch-Reentry-VT haufig serielle Schockabgaben eines implantierbaren Kardioverter-Defibrillators (ICD) auftreten konnen, die auf Rezidiven durch sofortige Reinitiierung der VT beruhen. Die Ablation des rechten Schenkels fuhrt zu einer sicheren Therapie der Bundle-Branch-Reentry-VT und kann haufige ICD-Interventionen verhindern. Nach Ablation der Bundle-Branch-Reentry-VT bleibt aufgrund der haufig schweren linksventrikularen Dysfunktion eine hohe Mortalitat bestehen, und die Patienten sollten einer kardialen Resynchronisationstherapie (CRT-D) zugefuhrt werden.

Introduction Concealed structural abnormalities were detected by delayed enhancement - magnetic resonance imaging (DE-MRI) in patients with apparently idiopathic tachycardia of left ventricular (LV) origin. Basal septal fibrosis was evaluated as a potential arrhythmia substrate in patients with left ventricular outflow tract (LVOT) arrhythmias. Methods and results A total of 22 patients with LVOT arrhythmias, including frequent monomorphic premature ventricular complexes (PVCs) in 15 patients and ventricular tachycardia (VT) in 7 patients, underwent catheter ablation and DE-MRI. A total of 19 patients with frequent PVCs and 17 patients with idiopathic VT of other origin served as a control group. Basal septal intramural fibrosis as thin strip-shaped intramyocardial DE or as marked intramyocardial DE involving >25% of wall thickness was detected more frequently in patients with LVOT arrhythmias (41% and 32%) than in patients with non LVOT arrhythmias (14% and 3%). After successful ablation, 4/16 patients with basal septal intramural fibrosis and LVOT PVCs (n = 3) or LVOT VT (n = 1) compared with no patient without basal septal fibrosis experienced episodes of sustained VT with similar or different QRS morphology resulting in ICD therapy in three patients. Follow-up DE-MRI after PVC ablation (17 ± 7 months) revealed an increase in LV ejection fraction from 49 ± 5% to 56 ± 5% (n = 9) but the amount of septal DE remained unchanged. Conclusions Basal septal intramural fibrosis may serve as the arrhythmia substrate in a substantial part of patients with premature ventricular complexes (PVCs) and VT originating from the LVOT and identifies patients with continued risk for VT recurrence after initially successful ablation of LVOT arrhythmias.

BACKGROUND Typical left bundle branch block (LBBB) during ventricular tachycardia (VT) is a diagnostic criterion of bundle branch reentry tachycardia (BBRT) with activation of the right bundle in the anterograde direction. METHODS AND RESULTS Eleven patients (seven male, 60 ± 12 years) with nonischemic cardiomyopathy (left ventricular ejection fraction 37 ± 16%) presenting with BBRT were successfully treated by ablation of the right bundle. Among them, five patients had atypical surface electrocardiograms (ECGs) differing from a typical LBBB during the VT. Three patients with severe enlargement and dysfunction of the left ventricle had broadened irregular QRS complexes with rR or RS configuration in lead V6 during the BBRT. Two patients with enlargement and/or hypokinesia of the right ventricle had entirely or almost entirely negative complexes (QS) in the chest leads (V1-V6) during the VT. Activation mapping in these two patients revealed that the exit site of the BBRT was in the anterior right ventricle generating a negative concordance in the precordial leads. CONCLUSIONS Atypical surface ECGs with broadened irregular QRS complexes or negative concordance in the precordial leads can complicate the correct diagnosis of BBRT in patients with severe left ventricular dysfunction and involvement of the right ventricle.

Sustained ventricular tachycardia (VT) in patients with nonischemic cardiomyopathy (NICM) often involves midmyocardial and epicardial structures. Delayed-enhancement magnetic resonance imaging (DE-MRI) of scar and fibrosis is the method of choice to define the substrate of monomorphic VT. The aim of the study was to compare the outcome of endocardial vs. epicardial VT ablation in patients with epicardial DE-MRI substrates in NICM. Among 44 patients with NICM referred for VT ablation who underwent DE-MRI, 12 patients had an epicardial-only (n = 4) or predominantly epicardial DE-MRI substrate (n = 8). 9 of the 12 patients had a prior myocarditis. Endocardial-only VT ablation was successful in two patients with epicardial DE-MRI substrate. A pericardial access for epicardial mapping and ablation was attempted in 8 patients and could be accomplished in seven. Epicardial low voltage (

Aims: Catheter ablation is an established therapy in patients with symptomatic atrial fibrillation (AF) with increasing popularity. Pericardial effusion requiring intervention (PE) is one of the most threatening adverse outcomes. The aim of this study was to examine rates of PE after catheter ablation in a large 'real-world' data set in a German-wide hospital network. Methods and results: Using ICD and OPS codes, administrative data of 85 Helios hospitals from 2010 to 2017 was used to identify AF catheter ablation cases [Helios atrial fibrillation ablation registry (SAFER)]. PE occurred in 0.9% of 21 141 catheter ablation procedures. Patients with PE were significantly older, to a higher percentage female, had more frequently hypertension, mild liver disease, diabetes with chronic complications, and renal disease. Low hospital volume (

Aims: Atrial fibrillation (AFib) and atrial flutter (AFlut) are common arrhythmias with increased use of invasive procedures. A steady re-evaluation of relevant safety endpoints is recommended and both quality management and pay-for-performance programs are evolving. Therefore, the aims of this study were (i) to investigate and report overall in-hospital mortality and mortality of invasive arrhythmia-related procedures and (ii) to identify mortality predictors in a German-wide hospital network. Methods and results: Administrative data provided by 78 Helios hospitals between 2010 and 2017 were examined using International Statistical Classification of Diseases and Related Health Problems- and Operations and Procedures-codes to identify patients with AFib or AFlut as main discharge diagnosis or secondary diagnosis combined with invasive arrhythmia-related interventions. In 161 502 patients, in-hospital mortality was 0.6% with a significant decrease from 0.75% to 0.5% (P

Nonreentrant ventricular tachycardia (VT) originates in hearts without structural disease but occasionally can occur in patients with different cardiomyopathies equipped with an implantable cardioverter defibrillator (ICD). In a series of 142 ICD recipients with structural heart disease undergoing ablation for recurrent or incessant monomorphic VT, nonreentrant VTs were identified. Nonreentrant VTs were the cause of appropriate ICD interventions in 12 patients (8.4 %). The underlying heart disease was nonischemic cardiomyopathy in eight patients, prior myocardial infarction in two patients, and valvular cardiomyopathy in two patients with a mean left ventricular ejection fraction of 42 ± 7 %. Unresponsiveness to antitachycardia pacing and repetitive spontaneous re-initiation of the VT after defibrillation was the cause of frequent ineffective ICD interventions including repetitive ICD shocks in these patients. Using ICD interrogation, one or more episodes of a severe electrical storm (≥3 serial efficacious ICD shocks within 15 min) were more frequently documented in patients with nonreentrant VTs (10/12) than in patients with scar-related reentrant VTs (36/115). The origin of the nonreentrant VT was the left ventricular outflow tract in seven patients, the right ventricular outflow tract in three patients, and the tricuspid and mitral annulus in each one patient. Catheter ablation including epicardial mapping in 2 patients eliminated the nonreentrant VT in 11 of 12 patients and prevented recurrent VT storm. Repetitive nonreentrant VTs may be ineffectively treated by ICD interventions and can be the cause of an electrical storm in different cardiomyopathies.

For the treatment of increasingly complex cardiac arrhythmias, new catheter designs as well as alternative energy sources are constantly being developed. However, there is presently no in vitro method available for assessment of the temperature changes induced at various myocardial levels during energy delivery. Therefore, our study was aimed at developing an in vitro model to record and display the temperature kinetics during ablation in the entire muscle cross section. A sapphire glass pane was inserted into one wall of the in vitro experimental set-up. Due to its thermodynamic properties, the temperature distribution in an adjacent cross section of the cardiac muscle can be measured exactly (±1 °C) through this pane by means of a thermography camera. Computer-supported image processing enables the colour-coded and two-dimensional display of the temperature kinetics during the energy application at any location of the myocardial cross section (±0.5 mm). This new measuring methodology was validated by direct temperature measurements utilizing several intramyocardial thermo elements. This new method allows a temporal and spatial analysis of the temperature phenomena during ablation without the interference and spatial limitation of intramyocardial temperature probes. New ablation technologies can thus be evaluated, independent of the catheter configuration or source of energy used.

The aim of the study was to determine the long-term reliability of atrioventricular and intraventricular conduction and the implications for cardiac resynchronization therapy (CRT-D) following catheter ablation of bundle branch reentry tachycardia (BBRT) and interfascicular tachycardia. Fourteen patients with recurrent monomorphic ventricular tachycardia (VT) (n = 11) and incessant VT (n = 3) underwent catheter ablation of BBRT (n = 7), interfascicular tachycardia (n = 5) or both arrhythmias (n = 2). Successful ablation was achieved in all patients without intraprocedural atrioventricular (AV) block. Within 2 months after ablation, three patients with BBRT and pre-existing prolonged QRS developed a delayed third-degree AV block. During the follow-up of 2 years, two patients with interfascicular tachycardia developed a new left bundle branch block (LBBB) associated with worsening of heart failure. Three patients underwent upgrading of implantable cardioverter defibrillator therapy to CRT-D early after ablation which improved heart failure during the 6 months follow-up. During the long-term follow-up of 39 ± 13 months, VT storm recurred in one patient. Four of the 14 patients died of deterioration of heart failure and one had to undergo heart transplantation. Catheter ablation for BBRT in patients with prolonged QRS is associated with a high risk of delayed third-degree AV block. Ablation of interfascicular tachycardia can be associated with delayed LBBB. After ablation of bundle branch reentry, patients with prolonged QRS are candidates for cardiac resynchronization therapy but the mortality remains high.

Aims The purpose of the study was to evaluate the role of coronary venous mapping to identify epicardial ventricular tachycardia (VT) in patients with structural heart disease. Methods and results Epicardial mapping of the electrophysiological substrate through the coronary vein branches using a 2.2F, 16-pole microelectrode catheter was performed in 33 consecutive patients undergoing VT ablation. Twenty-six patients had a history of myocardial infarction and seven had a non-ischaemic cardiomyopathy. Endocardial ablation was successful in 19 of the 33 patients (58%). Low-amplitude fractionated diastolic electrograms with an electrogram–QRS interval amounting to 30–70% of the VT cycle length were recorded during the VT in the coronary vein branches in eight patients (24%). Endocardial ablation failed in seven of the eight patients with diastolic electrograms in the coronary veins, suggesting an epicardial involvement of the VT re-entry circuit. Among the patients with a suspected epicardial VT origin, four patients underwent epicardial ablation using a pericardial access after unsuccessful endocardial ablation which eliminated mappable VTs in all. Conclusion Recording of low-amplitude fractionated diastolic electrograms through the coronary veins facilitates the identification of VTs with an epicardial origin requiring mapping and ablation through a pericardial access.

Background: The entrainment mapping algorithm is used for ablation of ventricular tachycardia (VT) in right ventricular (RV) cardiomyopathy, but ablation at endocardial isthmus sites has only a moderate success rate. This study was performed to identify additional local electrogram characteristics associated with successful ablation. Patients and Methods: Using entrainment mapping, 45 reentry circuit isthmus sites were detected in 11 patients with RV cardiomyopathy presenting with 13 monomorphic VTs. Local bipolar electrograms were retrospectively analyzed at reentry circuit isthmus sites during VT, sinus rhythm, and programmed stimulation from the right ventricular apex (RVA), and compared between successful and unsuccessful ablation sites. Results: Ablation was successful at 10 reentry circuit isthmus sites and unsuccessful at 35 isthmus sites. During VT, a longer endocardial activation time relative to QRS onset, an increased electrogram-QRS interval as a percentage of VT cycle length, and a longer electrogram duration were found at successful in comparison to unsuccessful ablation sites. The presence of isolated diastolic potentials during sinus rhythm at reentry circuit isthmus sites, consistent with slow conduction or unidirectional conduction block, was associated with successful catheter ablation. Prolongation of the duration of the local multipotential electrogram by >100 ms during programmed RVA pacing at reentry circuit exit sites, indicating functional conduction disorder was also a marker of successful ablation. Conclusions: The demonstration of multipotential electrogram characteristics indicating fixed or functional conduction block may increase the likelihood of successful VT ablation at exit and central isthmus sites of reentry circuits in RV cardiomyopathy.

Data on the use of levosimendan in patients with myocardial infarction related cardiogenic shock already under combined catecholamine treatment and intra-aortic balloon counterpulsation (IABP) are scarce. Seven consecutive patients with refractory cardiogenic shock after ST-elevation myocardial infarction, multi-organ dysfunction syndrome and under maximal intensive care (combined catecholamine treatment, IABP) were treated with levosimendan (bolus 12 microg/kg i.v., thereafter 0.1 microg/kg over 24 h). Hemodynamic effects were registered invasively and monitored over 72h post infusion. Therapy with levosimendan significantly reduced required epinephrine dose after 48h (P=0.02 versus baseline). Norepinephrine dose had to be increased during the first 12 h of levosimendan (+25%; P=ns), but was significantly reduced at 72 h compared to baseline (median 0.14 versus 0.06 microg/kg/min after 72 h; P0.05). Cardiac power output increased (baseline 0.6 versus 1.1or = 48 h after infusion; P0.01) and systemic vascular resistance decreased (median 1294 dyn*s*cm-5 at baseline versus 858 dyn*s*cm-5 at 24 h; P0.05) after levosimendan infusion. IABP therapy could be weaned in all patients during 5 days after infusion and all patients survived the cardiogenic shock (ICU mortality 29%). Levosimendan as an adjunctive, rescue therapy in patients with severe cardiogenic shock may be safe with beneficial effects on hemodynamics over 72 h.

Patients with frequent premature ventricular contractions (PVCs) are often highly symptomatic with significantly reduced quality-of-life. We evaluated the outcome and success of PVC ablation in patients in the German Ablation Registry. The German Ablation Registry is a nationwide prospective multicenter database of patients who underwent an ablation procedure, initiated by the “Stiftung Institut fur Herzinfarktforschung” (IHF), Ludwigshafen, Germany. Data were acquired from March 2007 to May 2011. Patients underwent PVC ablation in the enrolling ablation centers. A total of 408 patients (age 53.5 ± 15 years, 55 % female) undergoing ablation for PVCs were included. 32 % of patients showed a co-existing structural heart disease. Acute ablation success of the procedure was 82 % in the overall patient group. In patients without structural heart disease, acute success was significantly higher compared with patients with structural heart disease (86 vs. 74 %, p = 0.002). All patients were discharged alive after a median of 3 days. No patient suffered an acute myocardial infarction, stroke, or major bleeding. After 12 months’ follow-up, 99 % of patients were still alive showing a significant different mortality between patients with structural heart disease compared with those without (2.3 vs. 0 %, p = 0.012). In addition, 76 % of patients showed significantly improved symptoms after 12 months of follow-up. Based on the data from this registry, ablation of PVCs is a safe and efficient procedure with an excellent outcome and improved symptoms after 12 months.

Introduction: Idiopathic left ventricular tachycardia (VT) originating from the left posterior fascicle can be eliminated by ablation at sites with abnormal diastolic potentials (DPs) during sinus rhythm. We investigated whether such DPs can also be recorded in patients with structural heart disease and VT involving the left bundle-Purkinje system. Methods and Results: Eight patients (mean age 67 ± 11 years) with nonischemic cardiomyopathy (n = 5) or prior myocardial infarction (n = 3) presented with VT involving the left bundle-Purkinje system (cycle length 376 ± 45 ms). Three types of VT were observed: macroreentrant VT with participation of both left bundle fascicles in three patients, fascicular VT involving the left posterior fascicle in two patients, and scar-related VT with Purkinje fibers as part of the reentrant circuit in three patients. In all patients, abnormal isolated DPs of low amplitude with a QRS—earliest DP interval of 374 ± 86 ms were found during sinus rhythm in the mid- or inferior left ventricular septum in areas with Purkinje potentials. The abnormal DPs during sinus rhythm coincided or were in proximity to DPs during the VT in six patients. VT ablation targeting the sites with the earliest abnormal DPs during sinus eliminated the VT in 7 of 8 patients with freedom from VT recurrence in six patients during the follow-up of 11 ± 5 months. Conclusions: Isolated DPs during sinus rhythm were found in proximity to the posterior Purkinje network in patients with VT involving the left bundle-Purkinje system associated with heart disease and can be used to guide successful catheter ablation.

Background: We describe immediate reinitiation of macroreentry ventricular tachycardia (VT) involving the His-Purkinje system by ventricular pacing from the electrode of an implantable cardioverter defibrillator (ICD) as a mechanism of VT storm refractory to ICD therapy. Methods and Results: Repetitive reinitiation of bundle branch reentry tachycardia (BBRT), interfascicular tachycardia, or both VTs by ventricular pacing was identified in four ICD patients presenting with VT storm or incessant VT. All patients had a pre-existing prolonged HV interval (75 ± 9 ms) and left bundle branch block (LBBB) or bifascicular block during sinus rhythm. The VTs included BBRT with LBBB in three patients and interfascicular tachycardia with right bundle branch block (RBBB) and left anterior or left posterior fascicular block in two patients. The paced beats from the ICD electrode exhibited a LBBB pattern of depolarization in two patients and a RBBB contour in V1 and V2 with left axis deviation in two patients. The QRS complex during pacing from the ICD electrode closely resembled that of the recurrent VT in all four patients suggesting that the pacing site of the ICD electrode was in proximity to the myocardial exit site of the bundle fascicle used for antegrade conduction during the reinitiated VT. Ventricular pacing from the ICD electrode after termination of the VT apparently encountered the retrograde refractoriness of this bundle fascicle and allowed immediate re-propagation of the wavefront orthodromically along the VT circuit. BBRT was eliminated by ablation of the right bundle branch. Successful ablation of the interfascicular tachycardias was achieved by targeting (1) an abnormal potential of the distal left posterior Purkinje network or (2) a diastolic potential during VT in the midinferior left ventricular (LV) septum. Conclusions: Repetitive reinitiation of BBRT and interfascicular tachycardia by ventricular pacing from the ICD electrode should be considered as a mechanism of VT storm refractory to ICD therapy in patients with a pre-existing conduction delay within the His-Purkinje system.

The Risk of Delayed Higher-Degree AV Block. Introduction: Delayed higher-degree atrioventricular (AV) block can develop after slow pathway ablation for AV nodal reentrant tachycardia with a preexisting first-degree AV block. Retrograde fast pathway ablation is considered as an alternative approach for patients with a markedly prolonged PR interval and no demonstrable anterograde fast pathway function at baseline. This study aimed to determine the long-term reliability of AV conduction after retrograde fast pathway ablation in comparison to slow pathway ablation in patients with AV nodal reentrant tachycardia and a first-degree AV block at baseline. Methods and Results: Among 43 patients with AV nodal reentrant tachycardia and a prolonged PR interval (defined as >200 msec), 10 patients without demonstrable dual pathway physiology underwent ablation of the retrograde fast pathway, and 33 patients with dual pathway physiology underwent slow pathway ablation. Persisting intraprocedural second- or third-degree AV block requiring pacemaker implantation occurred in one patient (10%) after retrograde fast pathway ablation and in one patient (3%) after slow pathway ablation. During the long-term follow-up of 61 ± 39 months after retrograde fast pathway ablation, no delayed second- or third-degree AV block occurred, and the PR interval remained unchanged (308 ± 60 msec vs 304 ± 52 msec). During the follow-up of 37 ± 25 months after slow pathway ablation, a delayed complete heart block developed in two patients, and a second-degree AV block developed in two patients. Three patients aged 66, 75, and 76 years died suddenly of unknown cause 4, 16, and 48 months following slow pathway ablation, respectively. Conclusions: Slow pathway ablation was associated with a significant risk of a delayed higher-degree AV block in patients with AV nodal reentrant tachycardia and a prolonged PR interval at baseline. Retrograde fast pathway ablation for patients with a first-degree AV block and no demonstrable dual pathway physiology was associated with a higher intraprocedural risk of complete AV block but did not result in the development of higher-degree AV block during the long-term follow-up of up to 9 years.

Der implantierbare Cardioverter/Defibrillator hat sich als effektive Therapie bei Patienten mit lebensbedrohlichen ventrikularen Tachyarrhythmien etabliert. Durch Verhinderung des plotzlichen Herztods kommt es zwangslaufig zu einer Umverteilung im Spektrum der Todesursachen dieser Patienten. Bislang existiert jedoch keine Studie an einem grosen Patientenkollektiv, die eine genaue Differenzierung dieser Todesursachen ermoglicht. Wir analysierten uber einen mittleren Beobachtungszeitraum von 41±29 Monaten (3 Tage–12 Jahre) den Verlauf von 429 konsekutiven ICD-Patienten (KHK n=274, dilatative CMP n=97, sonstige n=23, keine kardiale Grunderkrankung n=35), mittleres Alter 62±12 Jahre (23–87 Jahre). Die Gesamtuberlebensrate lag bei 79,7%, davon konnten 3,5% einer Herztransplantation zugefuhrt werden. Insgesamt verstarben 2,1% der Patienten plotzlich. 60,9% aller Verstorbenen erlagen einer nicht-plotzlichen, kardialen Ursache (terminale Herzinsuffizienz 56,3%, Myokardinfarkt 4,6%). In 28,7% fuhrte ein nicht-kardiales Ereignis zum Tode (Malignome 11,5%, Sepsis 6,9%, Apoplex 4,6%). Verstorbene Patienten wiesen signifikant haufiger eine strukturelle Herzerkrankung (100 vs 92%, p

We report the case of a bundle branch reentrant tachycardia (BBRT) in a 40-yearold patient with a calcified bicuspid aortic valve and normal left ventricular function. The ventricular tachycardia was eliminated by successful radiofrequency ablation of the right bundle branch. As the aortic valve annulus is in close proximity to the specialized conduction system, premature degeneration of a bicuspid aortic valve may involve the bundle of His and the proximal bundle branches by invading calcifications. We speculate that calcifications invading the proximal bundle branches from the bicuspid aortic valve may have created the substrate for the BBRT in this patient.

Objectives: The aim of this study was to determine the long-term results of ablation for sustained focal atrial tachycardia in patients with and without a history of atrial fibrillation. Methods: A history of atrial fibrillation was documented in 25 of 111 patients (23%) with focal atrial tachycardias. We studied the results of focal ablation during a follow-up of 27 ± 22 months. Results: Enlargement of left atrium (Odds ratio 2.99) and septal origin of the atrial focus (Odds ratio 5.68) were independent predictors of coexisting atrial fibrillation. Patients with a septal origin of the focal atrial tachycardia were older (62 vs. 54 years) and had a higher rate of structural heart disease than patients with a non-septal site of origin (51 vs. 29%). A higher rate of atrial fibrillation was found in patients with anteroseptal (56%), midseptal (50%) and posteroseptal (36%) atrial tachycardias than in patients with focal atrial tachycardias arising from the crista terminalis (9%), the tricuspid (12%) and mitral annulus (0%), the ostia of thoracic veins (17%) and other right atrial (27%) and left atrial free wall sites (10%). During the follow-up, atrial fibrillation was documented in 3% of patients without preexisting atrial fibrillation. In patients with focal atrial tachycardia and a history of atrial fibrillation, at least one episode of atrial fibrillation was documented during follow-up in 64% of patients, but 60% of patients reported marked symptomatic improvement. Conclusion: An increased rate of coexisting atrial fibrillation was found in patients with a septal origin of focal atrial tachycardia. Ablation of the focal atrial tachycardia may eliminate both arrhythmias, but patients with a history of atrial fibrillation may still be prone to recurrences of atrial fibrillation after focal ablation.

AIMS Catheter ablation of the inferior vena cava-tricuspid annulus isthmus and continuation of antiarrhythmic drug therapy have been shown to be an effective hybrid therapy for atrial flutter which results from antiarrhythmic drug treatment of atrial fibrillation. The aim of this study was to determine the risk factors for recurrence of atrial fibrillation in patients undergoing hybrid therapy for antiarrhythmic drug-induced atrial flutter. METHODS AND RESULTS 90 patients with paroxysmal (n=46) or persistent atrial fibrillation (n=44) developed atrial flutter due to the administration of amiodarone (n=48), flecainide (n=22), propafenone (n=14) or sotalol (n=6). Recurrence of atrial fibrillation after ablation was assessed during follow-up on continued antiarrhythmic drug therapy and during long-term follow-up, irrespective of the initial antiarrhythmic medication. During the follow-up on continued antiarrhythmic drug therapy (16+/-13 months), recurrence of atrial fibrillation was documented in 24 of 90 patients (27%). The presence of accompanying pre-ablation episodes of atrial fibrillation on antiarrhythmic treatment (Odds ratio 7.1, 95% confidence interval 2.3 to 25, p=0.001) and decreased left ventricular ejection fraction (Odds ratio 3.7, 95% confidence interval 1.01 to 12.5, p=0.048) were significant and independent predictors of post-ablation atrial fibrillation. Antiarrhythmic medication was discontinued during long-term follow-up due to adverse drug effects (amiodarone, n=12; flecainide, n=1) in 13 patients (14%). During the long-term follow-up, irrespective of the initial antiarrhythmic medication (21+/-15 months), stable sinus rhythm was maintained in 60 of 90 patients (67%). CONCLUSION Hybrid therapy can be considered as the first line therapy for patients with antiarrhythmic drug-induced atrial flutter but patients should be carefully evaluated for accompanying pre-ablation episodes of atrial fibrillation and possible adverse drug effects before initiation of hybrid therapy.

Vorhofflimmern stellt die haufigste anhaltende Rhythmusstorung im klinischen Alltag dar. Kennzeichnend sind multiple, kontinuierliche Kreiserregungen in beiden Vorhofen. Die Initiierung und Aufrechterhaltung von Vorhofflimmern wird sowohl durch repetitiv auftretende Trigger als auch durch ein zugrundeliegendes Substrat begunstigt. Durch Mapping-Untersuchungen bei Patienten mit medikamentos therapierefraktarem paroxysmalem Vorhofflimmern konnten Muskelpotenziale aus den Pulmonalvenenmundungen als haufigste Trigger fur die Entstehung von Vorhofflimmern identifiziert werden. In klinischen Studien wird derzeit untersucht, in wieweit durch eine Katheterablation der triggerenden Pulmonalvenenfoci die Initiierung von Vorhofflimmern verhindert werden kann. Neben der atrialen Extrasystolie werden eine Modulation der Herzfrequenz durch das autonome Nervensystem sowie andere supraventrikulare Arrhythmien mit Degeneration in Vorhofflimmern als begunstigende Triggermechanismen diskutiert. Die Beobachtung einer erhohten Inzidenz von Vorhofflimmern bei Patienten mit symptomatischen Bradykardien fuhrte zur Weiterentwicklung der atrialen Stimulationstherapie zur Pravention von Vorhofflimmern. Die Effizienz dieser Therapieform wird derzeit in mehreren klinischen Studien bei Patienten mit und ohne primare Schrittmacherindikation untersucht. Bis heute ist nicht bekannt, in welchem Ausmas anatomische und elektrophysiologische Eigenschaften der Vorhofe die Initiierung und Aufrechterhaltung von Vorhofflimmern begunstigen. Adaptationsprozesse des Vorhofmyokards an Vorhofflimmern, auch als „atrial remodeling” bezeichnet, gehen mit einer Verkurzung der atrialen Refraktarzeit, einer Verlangsamung atrialer Erregungsleitung, einer Abnahme der Aktionspotenzialdauer sowie einem progressiven Ruckgang der L-type Ca2+-Kanale und Mikrofibrosierungen im Vorhofgewebe einher. Diese Veranderungen werden heute als weitgehend reversibel betrachtet. Eine Beeinflussung der Adaptationsprozesse wird durch pharmakologische Weiterentwicklungen auf dem Gebiet der Modulation von Ionenkanalproteinen und der Blockade von Rezeptoren im Angiotensinstoffwechsel angestrebt.

Pulmonary vein bigeminy is the pair of a second, late and ectopic pulmonary vein potential following atrial far-field activation and a first passive pulmonary vein potential during sinus rhythm. The aim of this study was to determine the electrophysiological characteristics of pulmonary vein bigeminy and to evaluate its relevance as a trigger for paroxysmal atrial fibrillation.

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±107ms) 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.

Early reinitiation of atrial fibrillation (ERAF) following external or internal electrical cardioversion is one of the factors determining unsuccessful electrical cardioversion. Prevention of ERAF has not been studied systematically in patients on amiodarone therapy.

Aims Antiarrhythmic 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 Results Among 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) (27724 ms) was significantly longer as compared to the cycle length of atrial flutter in group I (24733 ms) and group III patients (23528 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 83 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%). Conclusion These 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. (Eur Heart J 2000; 21: 565–572)

Prerequisite for succesful radiofrequency catheter ablation of tachycardias is the exact mapping during the electrophysiological study. The new mapping system CARTO allows a three-dimensional color-coded electroanatomic map of impulse propagation using electromagnetic technology. The aim of this study was to determine the feasibility and safety of the new electromagnetic mapping technology CARTO for atrial tachycardias.

Bei Patienten mit Herzinsuffizienz konnen aufgrung struktureller und funktioneller Veranderungen auf Vorhofebene supraventrikulare Herzrhythmusstorungen wie Vorhofflattern und Vorhofflimmern auftreten. Wahrend sich beim Vorhofflattern die Radiofrequenz-Katheterablation als nichtmedikamentose kurative Therapie bereits mit sehr guten Erfolgsquoten etabliert hat, werden bei medikamentos therapierefraktarem Vorhofflimmern zur Zeit verschiedene, potentiell auch kurative Therapieformen im Rahmen koutrollierter Studien wissenschaftlich untersucht. Die Induktionsmechanismen und die Erfolgsraten der verschiedenen Therapieverfahren sowie Akut- und Spatkomplikationen abgewartet werden, um in der Zukunft fur jeden Patienten eine individuell optimierte alternative Therapie einsetzen zu konnen.

Die Katheterablation mit Radiofrequenzstrom ist heute als etabliertes Behandlungsverfahren bei typischem Vorhofflattern anzusehen. Durch eine lineare Lasion am Boden des rechten Vorhofs zwischen Trikuspidalring und Vena cava inferior („Isthmus”) kann der dem typischen Vorhofflattern zugrundeliegende Makro-Reentry-Kreis dauerhaft unterbrochen werden. Ein entscheidender Fortschritt zur Senkung der Rezidivrate nach Katheterablation von Vorhofflattern wurde mit der Einfuhrung des elektrophysiologischen Kriteriums des bidirektionalen Isthmus-blocks erzielt. Die Erfolgsrate der Ablation wird mit etwa 85 bis 90%, die Rezidivrate mit etwa 10 bis 15% angegeben. Ein klinisches Hauptproblem nach erfolgreicher Katheterablation von typischem Vorhofflattern ist das Auftreten von paroxysmalem Vorhofflimmern. Vorhofflimmern nach Isthmusablation von Vorhofflattern tritt vor allem bei Patienten mit vorbestehend vorhandenem Vorhofflimmern auf; demgegenuber ist nur bei etwa 20% der Patienten nach Ablation von Vorhofflattern mit neu auftretendem Vorhofflimmern zu rechnen.

Als repetitive monomorphe ventrikulare Tachykardie (RMVT) wird eine rechtsventrikulare Tachykardie bei Patienten ohne strukturelle Herzerkrankung mit uberwiegend singularer, bigeminiformer oder salvenartiger monomorpher ventrikularer Extrasystolie bezeichnet. Zumeist liegt eine Linksschenkelblock-Konfiguration mit Indifferenz- oder Steiltyp wahrend der ventrikularen Tachykardie vor. In unserem Kollektiv von 20 Patienten war es bei 35% anamnestisch zu Synkopen gekommen. In drei Fallen war eine Synkope Erstmanifestation der RMVT. Bei 25% unserer RMVT-Patienten waren auch anhaltende ventrikulare Tachykardien mit einer Dauer >3 min im Langzeit-EKG dokumentiert. Wesentliche Differentialdiagnose einer RMVT ist die paroxysmale anhaltende Form der idiopathischen ventrikularen Tachykardie. Neben dem typischen salvenartigen Auftreten der ventrikularen Extrasystolie ist die Belastungsabhangigkeit wegweisend fur die Diagnose einer RMVT. In 85–90% der Falle gelang in unserem Patientenkollektiv die Auslosung von Salven einer RMVT oder einer anhaltenden RMVT mittels Ergometrie oder eines Isoproterenol-Testes. Die Auslosung einer RMVT mittels programmierter rechtsventrikularer Stimulation gelang in unserem Patientenkollektiv nur in 13% der Falle. Somit ist die Durchfuhrung einer elektrophysiologischen Untersuchung nur zur Unterscheidung einer ventrikularen von einer supraventrikularen Tachykardie mit Schenkelblock oder zum Ausschlus einer anderen ventrikularen Tachyarrhythmie bei stattgehabter Synkope erforderlich. Die Prognose der RMVT ist gut; in unserem Kollektiv von RMVT-Patienten traten wahrend einer Nachbeobachtungszeit von bis zu 4 Jahren keine lebensbedrohlichen ventrikularen Tachyarrhythmien auf. Die Mehrzahl der Patienten mit RMVT last sich mit Verapamil oder β-Blocker ausreichend gut einstellen. Gelegentlich ist eine Therapie mit einem Klasse-III-Antiarrhythmikum erforderlich. Wahrend bei der paroxysmalen anhaltenden Form der idiopathischen ventrikularen Tachykardie bei medikamentoser Therapierefraktaritat eine Katheterablation mit hervorragenden Erfolgsaussichten vorgenommen werden kann, ist die Durchfuhrung einer Katheterablation bei RMVT nur in seltenen Fallen indiziert.

Die erfolgreiche Radiofrequenz-Katheterablation tachykarder Rhythmusstorungen setzt eine genaue Lokalisation des arrhythmogenen Substrats wahrend der elekrophysiologischen Untersuchung voraus. Mit Hilfe der elektromagnetischen Technologie des neuen Mappingsystems CARTO™ ist die dreidimensionale farbcodierte elektroanatomische Darstellung der Aktivierungssequenz moglich. Mapping der sinutrialen Aktivierung des rechten Vorhofs bei 11 Patienten lieferte erste klinische Erfahrungen mit diesem neuen System. Die physiologische Aktivierungssequenz lies sich bei allen Patienten komplikationslos dreidimensional darstellen und der Sinusknoten als physiologischer Aktivitatsfokus mit interindividueller Variabilitat lediglich in der Sagittalebene lokalisieren. Das nichtfluoroskopische Mappingsystem erlaubt eine Visualisierung der elektrischen Aktivitat und kann dadurch die Lokalisierung des arrhythmogenen Substrats wahrend Tachykardie vor erfolgreicher Ablation erleichtern.

Idiopathic left ventricular tachycardia (ILVT) with right bundle branch block and left axis deviation originates from the left posterior fascicle—Purkinje fiber network. Scar-related ventricular tachycardias (VTs) with Purkinje fibers as a part of the reentry circuit have also been described in patients with structural heart disease. Nine patients with fascicular VT (left posterior, n = 8; left anterior, n = 1) with preserved left ventricular ejection fraction (60 ± 10 %) underwent cardiac magnetic resonance imaging (MRI) including functional analysis and delayed enhancement magnetic resonance imaging (DE-MRI). No definite structural abnormalities were detected by DE-MRI in four patients. DE-MRI revealed unifocal or multifocal areas of fibrosis or scar in three patients corresponding to the regions where typical Purkinje potentials guided successful ablation of the sustained fascicular VT. A false tendon extending from the free wall to the septum was found in one patient. Moderate reduction of left ventricular ejection fraction associated with septal or multifocal left ventricular fibrosis was detected in two patients with ventricular bigeminy originating from the left posterior fascicle. During the follow-up of 29 ± 22 months after successful catheter ablation in the nine patients, one patient with septal fibrosis detected by DE-MRI had VT recurrence and received an implantable cardioverter defibrillator. Detection of local areas of fibrosis or scar by DE-MRI may help to distinguish idiopathic fascicular tachycardia from scar-related fascicular VT in patients with preserved left ventricular function.

The purpose of this case report is to describe the effects of an MRI performed on a patient without realizing that an ICD has been previously implanted. After a few seconds of imaging the adversity was recognized and the examination was stopped immediately. The patient was not pacemaker dependent and had neither physical complaints nor electrocardiographic changes in the surface ECG. A consecutively performed ICD assessment showed a backup mode with standard parameters for pacing (VVI 50 beats/min) and arrhythmia detection and treatment. The device could not be programmed by the external programmer. With the exception of printing out the parameters, all software functions were no longer feasible. A device examination by the manufacturer after ICD replacement showed that a major portion of the device memory was corrupt. Even ICDs of a newer generation are susceptible to magnetic interference, with the danger of complete loss of programmability.

A 45-year-old woman, who had received a single-chamber implantable cardioverter defibrillator (ICD) due to ventricular fibrillation 5 years ago, was admitted for catheter ablation of incessant right ventricular outflow tract bigeminy. After successful ablation recurrent torsades de pointes associated with a prolonged corrected QT (QTc) interval were initiated by polymorphic premature ventricular complexes. Genetic testing revealed a heterozygous missense mutation in the SCN5A-gene (p.Arg190Gln, Exon 5), consistent with long QT-syndrome 3. DDDR pacing following implantation of an atrial lead prevented further ventricular tachyarrhythmias.

Introduction: The purpose of this study was to examine the reentrant circuit of ventricular tachycardias (VTs) involving the left anterior fascicle (LAF) in nonischemic cardiomyopathy. Methods and Results: Six patients with nonischemic cardiomyopathy presented with VTs involving the LAF. Potentials in the diastolic or presystolic phase of the VT were identified close to the LAF in 3 patients and in the mid or inferior left ventricular (LV) septum in 3 patients. Superimposed on a CARTO or NavX 3-dimensional voltage map, the diastolic and presystolic potentials were recorded within or at the border of a low-voltage zone in the LV septum in all cases. In 2 patients, both left bundle fascicles participated in the reentrant circuit including a possible interfascicular VT in one case. Ablation targeting the diastolic or presystolic potentials near the LAF or in the midinferior LV septum eliminated the VTs in all patients with the occurrence of a left posterior fascicular block and the delayed occurrence of a complete atrioventricular block in each one patient. During the follow-up of 23 ± 20 months after ablation, 4 patients were free of ventricular tachyarrhythmias. Due to detoriation of heart failure, one patient died after 12 months and one patient underwent heart transplantation after 40 months. Conclusions: Slow conduction in diseased myocardium close to the LAF or in the middle and inferior aspects of the LV septum may represent the diastolic pathway of VT involving the LAF.

The regulation of adenylyl cyclase components and of adenylyl cyclase activity by noradrenaline and tumour necrosis factor alpha (TNF alpha) was studied in rat cardiomyocytes. Long-term treatment of rat cardiomyocytes in the presence of noradrenaline leads, in addition to a down-regulation of beta 1-adrenoceptors, to an increase in the level of inhibitory G protein alpha-subunits and to a heterologous desensitization of adenylyl cyclase stimulation. Similar to the noradrenaline exposure, incubation of the cardiomyocytes in the presence of the cytokine TNF alpha (10 U.ml-1) also increases the level of Gi alpha proteins. However, in contrast to the noradrenaline treatment, which apparently induces a selective up-regulation of Gi alpha, the TNF alpha exposure also increases the level or activity of other components of adenylyl cyclase, such as the level of membrane beta 36-subunits of G proteins and, most likely, the level of the alpha-subunits of the stimulatory G protein (Gs alpha) and the activity of adenylyl cyclase catalytic subunit. While noradrenaline treatment desensitizes receptor-dependent and independent adenylyl cyclase activity, treatment of the cells with TNF alpha induces a sensitization of adenylyl cyclase stimulation. The data indicate that only a selective increase in the level of inhibitory G protein alpha subunits decreases adenylyl cyclase activity. The hypersensitivity of adenylyl cyclase induced by TNF alpha exposure may be due to concomitant alterations of other components of the adenylyl cyclase signal transduction system.

Although often not considered, the heart is one of the targets of multiple organ failure in sepsis and septic shock, with myocardial depression being a prominent component of this "acute septic cardiomyopathy". Hypotheses concerning the etiology of this depression are increasingly elucidated on a cellular level, including dysfunction of the beta-adrenoceptor/G protein/adenylate cyclase system, calcium channel blockade by cardiodepressant factor, contractile impairment by activated leucocytes, as well as inhibition of protein synthesis by Pseudomonas exotoxin A. In the search for "mechanisms of myocardial depression in sepsis", isolated cardiomyocytes may play a role as research tools with respect to: a) discrimination between direct and indirect cardiodepressant effects; b) identifying not only the acute, but also chronic toxin- and mediator-induced cardiodepression; c) clarification of the mechanism of action of cardiodepressant bacterial toxins and sepsis mediators; d) establishment of in vitro models of leucocyte-mediated cardiodepression in sepsis.

In this report we describe a 42-year-old man with idiopathic pulmonary fibrosis with a progressive course who underwent right single-lung transplantation in November 2007. The post-operative course showed a decline of gas exchange, and chest X-ray revealed pneumonic infiltrates. Computerized tomography (CT) scans showed high-grade stenosis of the right superior pulmonary vein. The pulmonary vein stenosis was treated with percutaneous transseptal stent implantation leading to rapid improvement of gas exchange and clinical condition, and a retransplantation could be avoided.

A definitive diagnosis of cardiac sarcoidosis relies on the results of endomyocardial biopsy. In this Case Study Greif et al. describe a patient whose biopsy was negative for sarcoidosis—leading to a diagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy. Sarcoidosis was only revealed after the patient had progressed to end-stage heart failure and undergone cardiac transplantation several years later. Background A 37-year-old male with a history of palpitations and ventricular tachycardia was diagnosed with arrhythmogenic right ventricular dysplasia/cardiomyopathy on the basis of clinical assessment, electrocardiography and echocardiography. Over the following 3 years the patient progressed to end-stage heart failure and eventually underwent heart transplantation. Histological analysis of the explanted heart revealed the presence of numerous noncaseating granulomas. Investigations Electrocardiography, echocardiography, 24 h Holter monitoring, cardiac MRI, coronary angiography, endomyocardial biopsy, exercise testing, electrophysiological study, laboratory examinations and histological examination of the explanted heart. Diagnosis Cardiac sarcoidosis. Management Immunosupressive and corticosteroid therapy. Routine endomyocardial biopsy is planned.