Peri-interventional combined anticoagulation and antithrombotic therapy in atrial fibrillation ablation: A retrospective safety analysis

   Background: Catheter ablation (CA) of atrial fibrillation (AF) requires an intensified peri-inter­ventional anticoagulation scheme to avoid thromboembolic complications. In patients with cardiac or extracardiac artery disease, an additional antiplatelet treatment (AAT) is at least temporally necessary especially after a percutaneous intervention with stent implantation. This raises the question whether these patients have a higher peri-interventional bleeding risk during CA of AF. Methods: The data of 1235 patients with CA of AF were retrospectively analyzed in terms of bleeding events, ablation type, antithrombotic medication and comorbidities such as coronary artery disease and components of the HAS- BLED score. Peri-interventional bleeding events were classified in accordance with the BARC classification. Differentiations were made between slight femoral bleeding (based on type 1), severe femoral bleeding and pericardial effusion without pericardiocentesis (based on type 2) with the need of further hospitalization, the need of transfusion (based on type 3a) and pericardial tamponades requiring pericardiocentesis (based on type 3b). Results: 1131/1235 (91.6%) patients were exclusively under anticoagulation and 187 (15.3%) patients were also on AAT. There were no statistically significant differences in type 1 and 3b bleeding complica­tions or the occurrence of femoral pseudoaneurysms between both groups. However, type 2/3a bleeding complications, mostly femoral bleedings, were significantly more frequent in the patient group with AAT (3.2% vs. 7.5%, p = 0.006). Conclusions: An additional antiplatelet therapy increases the risk of severe femoral bleeding events during CA of AF. It appears reasonable to perform the elective procedure of AF ablation after the dis­continuation of AAT.

Spin dynamics in semiconductors

This article reviews the current status of spin dynamics in semiconductors which has achieved a lot of progress in the past years due to the fast growing field of semiconductor spintronics. The primary focus is the theoretical and experimental developments of spin relaxation and dephasing in both spin precession in time domain and spin diffusion and transport in spacial domain. A fully microscopic many-body investigation on spin dynamics based on the kinetic spin Bloch equation approach is reviewed comprehensively.Comment: a review article with 193 pages and 1103 references. To be published in Physics Reports