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An im plantable defibrillator with dual chamber pacing may have advantages for pacing, sensing, and detection of bradyand tachyarrhythmia's. This study evaluates the safety and performance of a dual chamber implantable cardioverter defibrillator that incorporates an algorithm to discriminate supravertricular from ventricular arrhythmias. The 300 patients in this study had the device implanted for the following indications: ventricular tachycardia ( 47%), sudden cardiac death survivorship (51 %), and prophylactic implants (2%), Patients received dual chamber pacing for accepted bradyarrhythmic (51.7%) or investigational indications. During a mean follow-up period of 1.7 months a total of 1,092 arrhythmia episodes in 96 patients were fully documented in the device memory: 66 patients experienced a total of 796 ventricular tachyarrhythmia episodes and 42 experienced a total of 296 supraventricular episodes. The device appropriately detected 100% of sustained ventricular tachyarrhythmia's while reducing the inappropriate detection of supraventricular tachyrrhythmias by 72% compared to single chamber rate only detection. The positive predictive value was 90.5% for ventricular tachyarrhythmia detection in episodes that exceeded the tachycardia detection rate. Adverse events observed in at least 2% of the patients were incisional pain (22%), inappropriate ventricular detection (7%), atrial lead dislodgement (4%), atnal over-sensing/undersensing (3%), hematoma (3%), incessant ventricular tachyarrhythmia (2%), and pneumothorax (2%). There were 23 deaths, none of which were attributed to device failure. The Gem DR is safe and effective for the detection and treatment of ventricular tachyarrhythmias. The dual chamber detection algorithm appropriately recognized supraventricuIar tachycardia with rapid ventricular rates 72% of the time while maintaining 200% detection of sustained ventricular tachyarrhythmia's [ABSTRACT FROM AUTHOR]

Preamble: Robotic magnetic navigation (RMN)-guided catheter ablation (CA) technology has been used for the treatment of cardiac arrhythmias for almost 20 years. Various studies reported that RMN allows for high catheter stability, improved lesion formation and a superior safety profile. So far, no guidelines or recommendations on RMN-guided CA have been published., Purpose: The aim of this consensus paper was to summarize knowledge and provide recommendations on management of arrhythmias using RMN-guided CA as treatment of atrial fibrillation (AF) and ventricular arrhythmias (VA)., Methodology: An expert writing group, performed a detailed review of available literature, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Recommendations on RMN-guided CA are presented in a guideline format with three levels of recommendations to serve as a reference for best practices in RMN procedures. Each recommendation is accompanied by supportive text and references. The various sections cover the practical spectrum from system and patient set-up, EP laboratory staffing, combination of RMN with fluoroscopy and mapping systems, use of automation features and ablation settings and targets, for different cardiac arrhythmias., Conclusion: This manuscript, presenting the combined experience of expert robotic users and knowledge from the available literature, offers a unique resource for providers interested in the use of RMN in the treatment of cardiac arrhythmias., Competing Interests: The Erasmus MC has received research grants from Acutus Medical, Biosense Webster and Stereotaxis. TS-T has received an educational grant from Abbott, a contract for education and advisory activities with Biotronik and consultancy contract with Acutus Medical and Ablacon. SW has received honoraria from Biotronik en Daiichi Sankyo. S-CY has received a research grant from Medtronic and honoraria from Medtronic and Boston Scientific. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Noten, Szili-Torok, Ernst, Burkhardt, Cavaco, Chen, Cheung, de Chillou, Crystal, Cooper, Gasparini, Geczy, Goehl, Hügl, Jin, Kampus, Kazemian, Khan, Kongstad, Magga, Peress, Raatikainen, Romanov, Rossvoll, Singh, Vatasescu, Wijchers, Yamashiro, Yap and Weiss.)

Patients with atrial fibrillation may require rhythm control therapy in addition to anticoagulation therapy for the prevention of stroke. Since 2012, the European Society of Cardiology and European Heart Rhythm Association guidelines have recommended non-vitamin K antagonist oral anticoagulants, including rivaroxaban, for the prevention of stroke in patients with atrial fibrillation. During the same period, these guidelines have also recommended dronedarone or amiodarone as second-line rhythm control agents in certain patients with atrial fibrillation and no contraindications. Amiodarone and dronedarone both strongly inhibit P -glycoprotein, while dronedarone is a moderate and amiodarone a weak inhibitor of cytochrome P450 3A4 (CYP3A4). Based on these data and evidence from physiologically based pharmacokinetic modelling, amiodarone and dronedarone are expected to have similar effects on rivaroxaban exposure resulting from P -glycoprotein and CYP3A4 inhibition. However, the rivaroxaban label recommends against the concomitant use of dronedarone, but not amiodarone, citing a lack of evidence on the concomitant use of rivaroxaban and dronedarone as the reason for the different recommendations. In this report, we discuss evidence from clinical studies and physiologically based pharmacokinetic modelling on the potential for increased rivaroxaban exposure resulting from drug-drug interaction between rivaroxaban and dronedarone or amiodarone. The current evidence supports the same clinical status and concomitant use of either amiodarone or dronedarone with rivaroxaban, which could be considered in future recommendations., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

The non-vitamin K antagonist oral anticoagulant rivaroxaban is used in several thromboembolic disorders. Rivaroxaban is eliminated via both metabolic degradation and renal elimination as unchanged drug. Therefore, renal and hepatic impairment may reduce rivaroxaban clearance, and medications inhibiting these clearance pathways could lead to drug-drug interactions. This physiologically based pharmacokinetic (PBPK) study investigated the pharmacokinetic behavior of rivaroxaban in clinical situations where drug clearance is impaired. A PBPK model was developed using mass balance and bioavailability data from adults and qualified using clinically observed data. Renal and hepatic impairment were simulated by adjusting disease-specific parameters, and concomitant drug use was simulated by varying enzyme activity in virtual populations (n = 1000) and compared with pharmacokinetic predictions in virtual healthy populations and clinical observations. Rivaroxaban doses of 10 mg or 20 mg were used. Mild to moderate renal impairment had a minor effect on area under the concentration-time curve and maximum plasma concentration of rivaroxaban, whereas severe renal impairment caused a more pronounced increase in these parameters vs normal renal function. Area under the concentration-time curve and maximum plasma concentration increased with severity of hepatic impairment. These effects were smaller in the simulations compared with clinical observations. AUC and C max increased with the strength of cytochrome P450 3A4 and P-glycoprotein inhibitors in simulations and clinical observations. This PBPK model can be useful for estimating the effects of impaired drug clearance on rivaroxaban pharmacokinetics. Identifying other factors that affect the pharmacokinetics of rivaroxaban could facilitate the development of models that approximate real-world pharmacokinetics more accurately., (© 2020 The Authors. The Journal of Clinical Pharmacology published by Wiley Periodicals LLC on behalf of American College of Clinical Pharmacology.)

Aims: Prevention of sudden cardiac death by means of the implantable cardioverter/defibrillator (ICD) is considered to be a lifelong therapy. However, it is still unresolved if patients who never experienced an appropriate ICD intervention during generator longevity really need to undergo device replacement., Methods and Results: The INSURE trial was a multicentre prospective observational cohort study that enrolled patients at the time of their first ICD replacement. Patients with and without previous appropriate ICD therapy were enrolled prospectively and were evaluated every 3-6 months after ICD replacement. Primary endpoint of the study was the first occurrence of appropriate ICD therapy after device replacement. Five hundred and ten patients (83% males, mean age 65 ± 10 years, mean ejection fraction 39 ± 16%) were enrolled between 2002 and 2007 in the study after an average lifespan of their first ICD generator of 62 ± 18 months. Three years after elective ICD replacement, the rates of appropriate ICD therapies in patients with (n = 245) and without (n = 265) former appropriate ICD intervention were 48.1 and 21.4% (adjusted hazard ratio 3.08, CI: 2.15-4.39, P < 0.001). Notably, no predictive factors for lower need of ICD therapy could be identified in patients without prior appropriate ICD intervention., Conclusions: In this study, a significant number of ICD-indicated patients without the need for therapy by their first device received appropriate ICD intervention after generator replacement. There were no predictors for lower need of ICD therapy. Hence, ICD replacement appears still necessary in patients without prior ICD interventions.

Unlabelled: AF Burden After CRT Implantation., Aims: Cardiac resynchronization therapy (CRT) is increasingly used in congestive heart failure (CHF) patients (with cardiac dyssynchrony). In addition to delivering therapy, CRT devices offer a variety of diagnostic tools for continuous long-term monitoring of clinically relevant information (i.e., occurrence and duration of arrhythmia episodes)., Methods and Results: Eighty-four patients with drug-refractory CHF in NYHA-class II-IV received a CRT device. The response to CRT was assessed by determining NYHA class at baseline and at 3 months follow-up. Atrial fibrillation (AF) burden (defined as time of AF per day) was continuously measured by the device. A significant gradual reduction of AF burden (from 9.88 +/- 12.61 to 4.20 +/- 9.24 [hours/day]) and number of patients experiencing AF episodes (from 26 to 13) were observed during CRT., Conclusions: (1) Diagnostic features for long-term monitoring of physiological variables provide useful information on the state and course of AF and may improve disease management. (2) AF burden reduces over time during the first 3 months after CRT implantation.

Tetralogy of Fallot is the most common cyanotic cardiac malformation in late childhood and adult, occurring in approximately 0.25 of 1000 live births. Most patients undergo early surgical correction. Therefore, the natural history of this disease has been evaluated in only a few cases. We report a complex case of a tetralogy of Fallot, who reached the age of 74 years without surgical or medical treatment and who was transferred to our clinic after syncope due to ventricular tachycardia.

Overdrive pacing therapies are well established to treat patients with ventricular tachycardia. The main advantage is the quick and painless success with a high efficacy. Newer observations show that atrial arrhythmias with short cycle lengths (<200ms) can be terminated by painless overdrive pacing therapies as well. In the AT500 verification study and in the Jewel AF-trial, 30-60% of all treated atrial arrhythmias could be terminated by overdrive pacing. Nevertheless, these encouraging results need to be confirmed by additional randomized clinical trials. Especially the "hybrid" therapy (overdrive pacing in combination with an antiarrhythmic drug therapy) looks promising.

Introduction: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy of atrial antitachycardia pacing (ATP) and the performance of pacing for AT prevention implemented into a new pacemaker., Methods and Results: In patients with conventional indications for permanent pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary study objectives were to determine the safety of overall device functioning and its efficacy in terminating spontaneous AT. A secondary endpoint was to determine the reliability of AT detection. Pacemaker memory functions were used to analyze the impact of dedicated pacing algorithms on AT prevention. In 33 European and Canadian centers, 325 patients were enrolled (mean follow-up 2.3+/-1.3 months). Complication-free survival at 3 months was 88%. In 2,145 episodes stored with atrial electrograms, AT detection was confirmed in 97%. The algorithm for continuous overdrive pacing increased the percentage of atrial pacing to 97%. After ATP activation, 16,683 of 52,468 AT episodes were treated (120 patients). Of these, 8,903 episodes (53%) were terminated successfully by ATP. No proarrhythmic effect of preventive pacing or atrial ATP was observed. Preventive pacing algorithms increased the median percentage of atrial pacing from 62% to 97%. However, the number of AT/AF (atrial fibrillation) episodes (4.1 vs 4.1 per patient per day) and the time in AT/AF (13.7% vs 12.8%) was not significantly different before and after activation of preventive pacing., Conclusion: DDDRP pacing with a new system for AT therapy was safe and associated with successful pace-termination of AT in 53% of episodes. Preventive pacing and atrial ATP algorithms represent two new functions that can be implemented safely into pacemaker systems for nonpharmacologic treatment of ATs in patients requiring pacemaker therapy.

Unlabelled: The pectoral approach to implantation of cardioverter/defibrillators has the aim to further simplify the implantation of transvenous defibrillation systems. The PCD 7219 D/C is a device of the fourth generation which makes the pectoral implantation feasible due to a weight of 132 g, a size of 89 x 64 x 18 mm, a volume of 83 cm3 and a surface of 108 cm2. The use of the "active-can"-system (PCD 7219 C) requires the implantation of only one right ventricular lead. The PCD 7219 D/C was implanted in 75 patients with ventricular tachyarrhythmias, the follow-up period was 12 +/- 4 (1-24) months. Subpectoral implantation was feasible in 59 patients (79%), in 55 with a left pectoral, in 4 with a right pectoral approach due to previous left-sided operation or thrombosis of the left subclavian vein. Male sex (p < 0.005), body weight (p < 0.005) and body surface (p < 0.05) were predictors of pectoral implantation. In the 45 patients (60%) with a unipolar defibrillation system ("active can") the defibrillation threshold was significantly lower compared to those with a dual lead system (9.9 +/- 6.5, 2.5-24 Joule vs. 19 +/- 4.5, 6-24 Joule p < 0.0001). In one patient with pectoral and in one patient with abdominal implantation a dislodgement of the right ventricular lead was diagnosed and an operative revision was indicated., Conclusion: The down-sized implantable cardioverter/defibrillator PCD 7219 D/C makes the pectoral implantation feasible in the majority of patients. The use of the "active-can"-system requires the implantation of only one right ventricular lead with significantly lower defibrillation thresholds.