[Left atrial appendage clusure in nonvalvular atrial fibrillation : Clinical evidence 2017]. / Der Verschluss des linken Vorhofohrs bei nichtvalvulärem Vorhofflimmern zur Prophylaxe von Tod, Schlaganfall und Blutungen : Klinische Evidenz 2017.

Nonvalvular atrial fibrillation (AF) is the most common arrhythmia with a prevalence of 1-2% and affects approximately 15-20% of all octogenarians. Patients are at increased risk of thromboembolic stroke, with an overall risk of 5% per year. Thrombi form almost exclusively in the left atrial appendage (LAA), a blind sac-like heterogeneous structure trabeculated by pectinate muscles. In the past five decades, life-long oral anticoagulation (OAC) with vitamin K antagonists (VKA) has been the state-of-the art treatment to prevent stroke and systemic embolism from thrombi in AF. In the last decade, nonvitamin K dependent oral anticoagulants (NOAC) have been shown to be superior to VKA. Given the safety issues of indefinite OAC with either VKA or NOAC, it is plausible to consider left atrial appendage closure (LAAC) as an alternative strategy to prevent death, stroke or other systemic embolization, and bleeding. In recent years, LAAC has been compared to VKA in prospective randomized trials, yielding superior results regarding efficacy and noninferiority regarding safety in the mid-term. This review provides an update on the current state of LAAC in the field of prevention of death, stroke, and bleedings in patients suffering from nonvalvular AF. We elucidate the evidence and limitations of anticoagulation as the classical treatment paradigm, and review devices and techniques for LAAC. Most importantly, the current clinical evidence on efficacy and safety is outlined.

Incidence and long-term follow-up of silent cerebral lesions after pulmonary vein isolation using a remote robotic navigation system as compared with manual ablation.

BACKGROUND: The incidence of silent cerebral lesions (SCL) after atrial fibrillation (AF) ablation is highly variable, depending on the technology used. Recently, an increased risk for SCL has been described for a novel, nonirrigated ablation tool using multielectrode phased radiofrequency (PVAC). The aim of this prospective study was to evaluate the incidence and long-term follow-up of SCL in patients undergoing robotically assisted pulmonary vein isolation (RA-PVI) as compared with manual PVI. METHODS AND RESULTS: Circumferential PVI using irrigated radiofrequency current was performed on 70 patients (41 patients with paroxysmal AF, 59%). Fifty patients underwent RA-PVI and 20 patients underwent a manual approach. Cerebral MRI was performed the day before and the day after the ablation procedure; follow-up MRI was performed on 9 of 12 (75%) patients after a follow-up period of 21 months. SCLs were found in 12 of 70 (17%) patients in this study; the incidence of SCLs was similar in patients undergoing RA-PVI as compared with manually ablated patients (n=9, 18% versus n=3, 15%; probability value=1.0). In 1 patient undergoing manual PVI (1%), an SCL with asymptomatic subarachnoid hemorrhage was detected; the bleeding completely resolved within 1 month. Transient ischemic attack occurred in 1 (1%) patient 2 days after manual PVI. After a median follow-up period of 21 months, no residual SCLs were detected. CONCLUSIONS: The incidence of SCL using the robotic navigation system was 18% in this study. Incidence and size of SCL appears to be similar after RA-PVI as compared with manual PVI. Repeat MRI showed no residual SCLs at long-term follow-up.

Safe magnetic resonance image scanning of the pacemaker patient: current technologies and future directions.

Magnetic resonance imaging (MRI) is the imaging modality of choice in many clinical situations, and its use is likely to grow due to expanding indications and an ageing population. Many patients with implantable devices are denied MRI except in cases of urgent need, and when scans must be performed they are complicated by the need for burdensome and costly personnel and monitoring requirements that have the net effect of restricting access to scans. Several small studies, enrolling a total of 344 patients, suggest that some patients with conventional systems may undergo MR examinations without clinically overt adverse events. However, a number of potential interactions exist between implantable cardiac devices and the static and gradient magnetic fields and modulated radio frequency (RF) fields generated during MR scans; nearly all studies have reported pacing capture threshold changes, troponin elevations, ectopy, unpredictable reed switch behaviour, and other 'subclinical' issues with pacemakers and implantable cardioverter-defibrillators (ICDs) in patients who have undergone MRI. Attention has turned to devices that are specifically designed to be safe in the MRI environment. A clinical study of one such device documented its ability to be exposed to MRI in a 1.5 T scanner without adverse impact on patient outcomes or pacemaker system function. Such new technologies may enable scanning of pacemaker and ICD patients with reduced concerns regarding the short- and long-term effects of MRI. As importantly, these devices may increase the number of centres that are able to safely perform MRI and, thus, expand access to scans for patients with these devices.

Initial experience with magnetic resonance imaging-safe pacemakers : a review.

Due of its superior soft tissue imaging capabilities, magnetic resonance imaging (MRI) has become the imaging modality of choice in many clinical situations, as illustrated by the tremendous growth in the number of MRIs performed over the past 2 decades. In parallel, the number of patients who require pacemakers or implantable cardiac defibrillators is increasing as indications for these devices broaden and the population ages. Taken together, these phenomena present an important clinical issue, as MR scans are generally contraindicated-except in urgent situations-in patients who have implanted cardiovascular devices. Potentially deleterious interactions between the magnetic fields and radio frequency (RF) energy produced by MR equipment and implantable devices have been identified, including inhibition of pacing, asynchronous/high-rate pacing, lead tip heating, and loss of capture. New devices that incorporate technologies to improve MR safety in patients with pacemakers have recently received approval in Europe and are under evaluation in the United States. Initial data from these devices suggest that these devices are safe in the MRI environment.

Persistent iatrogenic atrial septal defect after a single-puncture, double-transseptal approach for pulmonary vein isolation using a remote robotic navigation system: results from a prospective study.

AIMS: Persistent iatrogenic atrial septal defect (iASD) after transseptal puncture for pulmonary vein isolation (PVI) has been described recently as a complication of PVI. No data exists evaluating systematically the incidence and clinical implications of iASDs after PVI using a remote robotic navigation system (RNS) with sheaths with a distinct larger outer diameter. METHODS AND RESULTS: In this prospective study, 40 patients with either paroxysmal (n = 22, 55%) or persistent symptomatic atrial fibrillation were treated with circumferential PVI using an RNS. In all patients, a single-puncture, double-transseptal approach was used to access the left atrium. Transoesophageal echocardiography was performed before and the day after PVI as well as after a 3 and 6 months follow-up (FU). The day after ablation an iASD was detected in 38 of 40 (95%) patients with a mean diameter of 3.45 +/- 1.5 mm. At 6-month FU, the iASDs were closed in 30 of 39 (78.9%) patients. During the 6-month FU period, no patient died or suffered from cerebral or cardiac embolism. CONCLUSION: After a single-puncture, double-transseptal approach for PVI using the RNS, iASDs show a high spontaneous closure rate of 78.9% after a 6-month FU period. Persistent iASDs following PVI with the RNS are not associated with an increased rate of paradoxical embolism or with relevant shunting.