Efficacy and safety of novel left ventricular pacing leads: 1-year analysis of the NAVIGATOR trial.

OBJECTIVES: Assess safety and performance of novel quadripolar preshaped left ventricular (LV) leads: NAVIGO 4LV 2D ('S shaped') and NAVIGO 4LV ARC ('U shaped'). METHODS: Patients indicated for cardiac resynchronisation therapy were enrolled in a multicentre, prospective, controlled study (NAVIGATOR, NCT03279484). Patients were implanted with either a NAVIGO 4LV 2D or ARC lead, and assessed at 10 weeks, 6, 12 and 24 months post-implant. Co-primary safety and performance endpoints were assessed at 10 weeks. Safety endpoint was the patients' rate free from lead-related complications. Performance endpoint was the rate of patients with successful lead performance, defined as LV pacing threshold ≤2.5 V at 0.5 ms on at least one pacing vector, and the absence of phrenic nerve stimulation at the final programmed configuration. Lead-related complications and electrical parameters were monitored throughout study. RESULTS: A NAVIGO 4LV lead was successfully implanted in 211 out of 217 patients (97.2%). The safety endpoint was met, with 100% and 96.1% of patients free from complications for NAVIGO 4LV 2D and ARC, respectively. The performance endpoint was met with 98.1% and 98.9% of patients with a successful lead performance for NAVIGO 4LV 2D and ARC, respectively. Over 12 months, the global complication-free rate for both leads was 97.1% (95% CI: 93.71% to 98.70%), with a mean pacing capture threshold of 1.23 V±0.73 V and a mean impedance of 951 Ω±300.1 Ω. CONCLUSION: A high implantation success rate and low complication rate was reported for the novel NAVIGO 4LV 2D and ARC leads, along with successful performance up to 12 months.

Alternative atrial pacing site to improve cardiac function: focus on Bachmann's bundle pacing.

Pacing from the right atrial appendage (RAA) prolongs the P wave duration and can induce interatrial and especially left-sided atrio-ventricular dyssynchrony. Pacing from Bachmann's bundle closely reproduces normal physiology and has the potential to avoid the electromechanical dysfunction associated with conventional RAA pacing. Interatrial conduction delay is associated with an increased risk of stroke, heart failure, and death. In addition to a reduction in atrial fibrillation, Bachmann's bundle pacing has emerging applications as a hemodynamic pacing modality. This review outlines the pathophysiology of atrial conduction disturbances and their potential remedies and provides the reader with a practical guide to implementing Bachmann's bundle pacing with an emphasis on the recapitulation of normal electrical and mechanical function.

Declining Risk of Sudden Cardiac Death in Heart Failure: Fact or Myth?

The notion that the risk of sudden cardiac death (SCD) in patients with heart failure (HF) is declining seems to be gaining traction. Numerous editorials and commentaries have suggested that SCD, specifically arrhythmic SCD, is no longer a significant risk for patients with HF on guideline-directed medical therapy. In this review, we question whether the risk of SCD has indeed declined in HF trials and in the real world. We also explore whether, despite relative risk reductions, the residual SCD risk after guideline-directed medical therapy still suggests a need for implantable cardioverter defibrillator therapy. Among our arguments is that SCD has not decreased in HF trials, nor in the real world. Moreover, we argue that data from HF trials, which have not adhered to guideline-directed device therapy, do not obviate or justify delays to implantable cardioverter defibrillator therapy. In this context, we underline the challenges of translating the findings of HF randomized, controlled trials of guideline-directed medical therapy to the real world. We also make the case for HF trials that adhere to current guideline-directed device therapy so that we can better understand the role of implantable cardioverter defibrillators in chronic HF.

[Approach to patients with Assurity® and Endurity® pacemakers : Recommendations from the nucleus of the Working Group Electrophysiology and Rhythmology of the German Cardiac Society]. / Vorgehen bei Patienten mit Assurity®- und Endurity®-Schrittmachern : Empfehlungen des Nucleus der Arbeitsgruppe Elektrophysiologie und Rhythmologie (AGEP) der Deutschen Gesellschaft für Kardiologie.

In a subset of patients with pacemaker models Assurity® and Endurity® (Abbott, Sylmar, California, USA; worldwide outside the USA approximately 83,000 devices), a mistake during production may have occurred resulting in insufficient adhesion between the pulse generator header and device housing which in turn may allow moisture to enter the header. This may cause loss of telemetry, switch to back-up mode, reduced battery longevity, or in worst case loss of pacing. Until June 2022, these malfunctions were reported for 128 devices worldwide (0.15%); no permanent harm to patients due to this issue has been reported. The nucleus of the AGEP suggests the following recommendations: (1) Patients with a device under safety advisory should be informed. (2) The risks for the patient in case of loss of stimulation should be assessed. Patients should be categorized into "likely pacemaker-dependent" (e.g., indication permanent atrioventricular [AV] block, no intrinsic rhythm at the last follow-up, percentage of ventricular pacing in the device memory > 90%), "unknown", or "likely not pacemaker-dependent" (e.g., indication sick sinus syndrome, intrinsic rhythm > 50 bpm at the last follow-up, percentage of ventricular pacing in the device memory < 1%). (3) In likely pacemaker-non-dependent patients, information about this issue should be provided together with an unchanged follow-up or a follow-up with shortened intervals (e.g., every 3 months) and/or remote monitoring. (4) In patients with unknown risk if stimulation failure occurs, at least follow-up intervals should be shortened to, for example, 3 months and/or remote monitoring should be initialized. In addition, risks and benefits of a device exchange should be weighed against each other. (5) In patients who are likely pacemaker-dependent, device exchange is recommended.

Association between electrical and mechanical remodeling after cardiac resynchronization therapy: systematic review and meta-analysis of observational studies.

Cardiac resynchronization therapy (CRT) may improve not only impaired left ventricular contractility but can also induce reverse remodeling of native conduction system. Measurement of intrinsic QRS complex width during follow-up is the simplest method to assess reverse electrical remodeling (RER). We aimed to provide a literature review and meta-analysis on incidence and impact of RER and its association with mechanical remodeling. A systematic review and random-effect meta-analysis of studies reporting data on RER was performed. A total of 16 studies were included in this meta-analysis with 930 patients undergoing CRT (mean age 64.0 years, 64.1% males). The weighted mean incidence of RER was 42%. Reverse mechanical remodeling assessed by echocardiography was more frequently observed in patients with RER compared to patients without RER (75.7% vs. 46.6%; odds ratio [OR] 3.7, 95% confidence interval [CI] 2.24-6.09, p < 0.01). Mechanical responders had a mean iQRS shortening of 7.7 ms, while mechanical non-responders experienced a mean widening of iQRS by 5.2 ms (p < 0.01). Clinical improvement was more frequent in patients with RER vs. patients without RER (82.9% vs. 49.0%; OR 5.26; 95% CI 2.92-9.48; p < 0.01). No significant difference in all-cause mortality between patients with and without RER was found. Mean difference between baseline intrinsic QRS and post-implantation paced QRS was significant in patients with later RER (21.2 ms, 95% CI 9.4-32.9, p < 0.01), but not in patients without RER (6.6 ms, 95% CI -2.2-15.4, p = 0.14). Gender, initial left bundle block morphology and heart failure etiology were found not to be predictive for RER. Our meta-analysis demonstrates that shortening of iQRS duration is a common finding during follow-up of patients undergoing CRT and is associated with mechanical reverse remodeling and clinical improvement. Clinical Trial Registration: Prospero Database-CRD42021253336.

Anatomy for right ventricular lead implantation.

To understand the position of a pacing lead in the right ventricle and to correctly interpret fluoroscopy and intracardiac signals, good anatomical knowledge is required. The right ventricle can be separated into an inlet, an outlet, and an apical compartment. The inlet and outlet are separated by the septomarginal trabeculae, while the apex is situated below the moderator band. A lead position in the right ventricular apex is less desirable, last but not least due to the thin myocardial wall. Many leads supposed to be implanted in the apex are in fact fixed rather within the trabeculae in the inlet, which are sometimes difficult to pass. In the right ventricular outflow tract (RVOT), the free wall is easier to reach than the septal due to the fact that the RVOT wraps around the septum. A mid-septal position close to the moderator band is relatively simple to achieve and due to the vicinity of the right bundle branch may produce a narrower paced QRS complex. Special and detailed knowledge is necessary for His bundle and left bundle branch pacing.

Anatomy for atrial lead implantation.

Positioning and fixation of pacemaker leads in the right atrium depends on advanced anatomic knowledge in order to correctly interpret information from fluoroscopy and electrograms. Particularly the inability to reach a certain position or to achieve lead stability requires familiarity with right atrial structures such as the Eustachian ridge or areas of trabeculated versus smooth myocardium. Only a good understanding of right atrial anatomy makes it possible to replace electrophysiologically suboptimal atrial pacing sites such as right atrial appendage or high lateral wall by electrophysiologically better septal atrial pacing sites.

Travelling with heart failure: risk assessment and practical recommendations.

Patients with heart failure are at a higher risk of cardiovascular events compared with the general population, particularly during domestic or international travel. Patients with heart failure should adhere to specific recommendations during travel to lower their risk of developing heart failure symptoms. In this Review, we aim to provide clinicians with a set of guidelines for patients with heart failure embarking on national or international travel. Considerations when choosing a travel destination include travel distance and time, the season upon arrival, air pollution levels, jet lag and altitude level because all these factors can increase the risk of symptom development in patients with heart failure. In particular, volume depletion is of major concern while travelling given that it can contribute to worsening heart failure symptoms. Pre-travel risk assessment should be performed by a clinician 4-6 weeks before departure, and patients should receive advice on potential travel-related illness and on strategies to prevent volume depletion. Oxygen supplementation might be useful for patients who are very symptomatic. Upon arrival at the destination, potential drug-induced photosensitivity (particularly in tropical destinations) and risks associated with the local cuisine require consideration. Special recommendations are needed for patients with cardiac implantable electronic devices or left ventricular assist devices as well as for those who have undergone major cardiac surgery.

Estimated incidence of previously undetected atrial fibrillation on a 14-day continuous electrocardiographic monitor and associated risk of stroke.

AIMS: There is uncertainty about whether and how to perform screening for atrial fibrillation (AF). To estimate the incidence of previously undetected AF that would be captured using a continuous 14-day ECG monitor and the associated risk of stroke. METHODS AND RESULTS: We analysed data from a cohort of patients >65 years old with hypertension and a pacemaker, but without known AF. For each participant, we simulated 1000 ECG monitors by randomly selecting 14-day windows in the 6 months following enrolment and calculated the average AF burden (total time in AF). We used Cox proportional hazards models adjusted for CHA2DS2-VASc score to estimate the risk of subsequent ischaemic stroke or systemic embolism (SSE) associated with burdens of AF > and <6 min. Among 2470 participants, the median CHA2DS2-VASc score was 4.0, and 44 patients experienced SSE after 6 months following enrolment. The proportion of participants with an AF burden >6 min was 3.10% (95% CI 2.53-3.72). This was consistent across strata of age and CHA2DS2-VASc scores. Over a mean follow-up of 2.4 years, the rate of SSE among patients with <6 min of AF was 0.70%/year, compared to 2.18%/year (adjusted HR 3.02; 95% CI 1.39-6.56) in those with >6 min of AF. CONCLUSIONS: Approximately 3% of individuals aged >65 years with hypertension may have more than 6 min of AF detected by a 14-day ECG monitor. This is associated with a stroke risk of over 2% per year. Whether oral anticoagulation will reduce stroke in these patients is unknown.

[How-to case report]. / How-to Case Report.

Case reports are often the first step of innovations and new techniques in science and thus are fundamental for some later established procedures. In addition, they have a great educational effect and offer young scientists the opportunity to gain their first experiences in writing manuscripts. In addition to an interesting detail (e.g. figure), a clear message is essential for a good case report.

[His bundle and left bundle branch pacing]. / His-Bündel- und Linksschenkelstimulation.

Cardiac pacemakers are an extremely effective treatment for bradycardia but can, however, cause desynchronization of ventricular contraction leading to cardiomyopathy. Pacing of the conduction system can prevent and even reverse desynchronization, which is impressively visible in echocardiography with speckle tracing. His' bundle and left bundle branch pacing requires a specific implantation technique, sheaths and leads which can achieve successful stimulation of the conduction system in up to 98% of cases. Data on conduction system pacing have been acquired in numerous studies but only a few randomized outcome studies. Therefore, in the current European guidelines His' bundle and left bundle branch pacing only have a low level recommendation. The guidelines recommend His' bundle pacing in patients in whom a coronary sinus lead cannot be implanted and in patients with permanent atrial fibrillation and planned atrioventricular (AV) node ablation for heart rate control. Additionally, conduction system pacing appears to be meaningful in patients with an AV block who require pacing of the ventricle for ≥20% of the time or who already show a slightly or moderately reduced left ventricular ejection fraction (36-50%). Even in patients scheduled for generator replacement who have developed a cardiac pacemaker-induced cardiomyopathy, the opportunity should not be missed to upgrade the system by implantation of a His' bundle electrode.