Background: Cardiac pacing has been shown to improve quality of life and prognosis of patients with bradycardia for almost 60 years. The latest innovation in pacemaker therapy was miniaturization of generators to allow leadless pacing directly in the right ventricle. There is a long history and extensive experience of leadless ventricular pacing in Austria. However, no recommendations of national or international societies for indications and implantation of leadless opposed to transvenous pacing systems have been published so far. Results: A national expert panel of skilled implanters gives an overview on the two utilized leadless cardiac pacing systems and highlights clinical advantages as well as current knowledge of performance and complication rates of leadless pacing. Furthermore, a national consensus for Austria is presented, based on recent studies and current know-how, specifically including indications for leadless pacing, management of infection, suggestions for qualification, and training of the operators and technical standards. Conclusions: Leadless pacing systems can be implanted successfully with a low complication rate, if suggestions for indications and technical requirements are followed. Condensed An overview of the two utilized leadless cardiac pacing systems is given, specifically highlighting clinical advantages as well as current knowledge of performance and complication rates. Furthermore, a national consensus for Austria is presented, specifically including indications for leadless pacing, management of infection, and suggestions for qualification and technical standards.

As in vivo real-life data are still scarce, we conducted a study to assess the safety and feasibility of cardiac magnetic resonance imaging (MRI) in patients with a leadless pacemaker system. In this prospective non-randomized interventional trial, we enrolled 15 patients with an MRI conditional Micra^® leadless pacemaker system to undergo either a 1.5 T or 3.0 T cardiac MRI scan. Clinical adverse events as well as device parameters such as pacing threshold, sensing, impedance, and battery life were assessed at baseline as well as 1 and 3 months after the scan. Device parameter changes between different time points were tested for statistical significance and compared with pre-set cut-off values. Fourteen patients underwent the cardiac MRI scan according to the protocol as well as the scheduled follow-up visits. One participant was excluded from analysis, as the MRI scan was not possible because of severe claustrophobia. Other clinical events did not occur during the scan and the follow-up period. Device parameters stayed stable and changes during the observational period were statistically not significant (changes vs. baseline: pacing threshold: 0.01 ± 0.05 V, P = 0.308, 0.01 ± 0.07 V, P = 0.419, sensing: −0.15 ± 1.11 mV, P = 0.658, −0.19 ± 1.17 mV, P = 0.800, impedance: −7.86 ± 30.7 Ohm, P = 0.447, −7.86 ± 25.77 Ohm, P = 0.183, at 1 and 3 months follow-up, respectively). Parameter changes were not statistically different between patients who underwent imaging at 1.5 T (n = 7) or 3.0 T (n = 7). In our set of patients with a Micra^® leadless pacemaker, cardiac magnetic resonance imaging at either 1.5 T or 3.0 T proved feasible and safe with no relevant changes in device parameters within 3 months of follow-up.

There are limited data on patients with leadless cardiac pacemakers (LCP) undergoing magnetic resonance imaging. The aim of this prospective, single-center, observational study was to evaluate artefacts on cardiovascular magnetic resonance (CMR) images in patients with LCP. Fifteen patients with Micra™ LCP, implanted at least 6 weeks prior to CMR scan, were enrolled and underwent either 1.5 Tesla or 3 Tesla CMR imaging. Artefacts were categorized into grade 1 (excellent image quality), grade 2 (good), grade 3 (poor) and grade 4 (non-diagnostic) for each myocardial segment. One patient was excluded because of an incomplete CMR investigation due to claustrophobia. LCP caused an arc-shaped artefact (0.99 ± 0.16 cm2) at the right ventricular (RV) apex. Of 224 analyzed myocardial segments of the left ventricle (LV) 158 (70.5%) were affected by grade 1, 27 (12.1%) by grade 2, 17 (7.6%) by grade 3 and 22 (9.8%) by grade 4 artefacts. The artefact burden of grade 3 and 4 artefacts was significantly higher in the 3 Tesla group (3 Tesla vs 1.5 Tesla: 3.7 ± 1.6 vs 1.9 ± 1.4 myocardial segments per patient, p = 0.03). A high artefact burden was particularly observed in the mid anteroseptal, inferoseptal and apical septal myocardial segments of the LV and in the mid and apical segments of the RV. Quantification of LV function and assessment of valves were feasible in all patients. We did not observe any clinical or device-related adverse events. CMR imaging in patients with LCP is feasible with excellent to good image quality in the majority of LV segments. The artefact burden is comparable small allowing an accurate evaluation of LV function, cardiac structures and valves. However, artefacts in the mid anteroseptal, inferoseptal and apical septal myocardial segments of the LV due to the LCP may impair or even exclude diagnostic evaluation of these segments. Artefacts on CMR images may be reduced by the use of 1.5 Tesla CMR scanners.

NT-pro-BNP is produced in the cardiac atria and ventricles in response to increased wall stress. It may be a marker of both AF disease progression and co-morbidities that affect success after pulmonary vein isolation (PVI). This single-center retrospective study analyzed the association between pre-procedural NT-pro-BNP serum levels and the long-term outcome after a first-ever PVI in cryo-technique. Patients were followed by searching the hospital information system and conducting structured telephone interviews. Treatment failure was defined as any relapse of atrial fibrillation (AF) occurring 90 days after the index PVI at the earliest. Kaplan–Meier survival curves and Cox proportional hazards models were computed to assess the impact of NT-pro-BNP on AF recurrence. Following 374 patients over a median of 3.8 years (range: 0.25–9.4 years), baseline NT-pro-BNP was associated with the combined endpoint in univariate analysis (HR 1.04 per 100 pg/mL increase, 95% CI: 1.02–1.07, p < 0.001). Results were virtually unchanged in the multivariate model or if the data were log-transformed. Intraprocedural left atrial pressure correlated positively with log NT-pro-BNP. NT-pro-BNP was associated with AF relapse during a long-term follow-up after first-ever cryo-PVI in our cohort of patients with predominantly normal left ventricular function. This lab parameter is easy to obtain and has significant potential to guide treatment decisions.