Catheter directed thrombolytic therapy and aspiration thrombectomy in intermediate pulmonary embolism with long term results

Background: Catheter directed thrombolysis (CDT) and thrombectomy represent well established techniques for the treatment of intermediate pulmonary embolism (IPE). The long-term effect of catheterdirected thrombolysis of IPE is unknown.Methods: Clinical, interventional and echocardiographic data from 80 consecutive patients with IPE who were treated with CDT were evaluated. Primary end-points were technical success and major adverse events. Secondary end-points were cardiovascular mortality, all-cause mortality, clinical success, rate of bleeding complications, improvement in pulmonary pressure and echocardiography parameters. CDT completed with alteplase (10 mg bolus and 1 mg/h maintenance dose) through a pig-tail catheter for 24 h. After 24 h, control pulmonary angiography was performed. Results: In total, 80 patients with a mean age of 59.0 ± 16.8 years were treated. CDT was successful after the first post-operative day in 72 (90%) patients, but thrombus aspiration and fragmentation was performed due to failed thrombolysis in 8 (10%) patients. Final technical and clinical success was reached in 79 (98.8%) and 77 (96.3%) patients, respectively. The mean CDT time in IPE was 27.8 ± 9.6 h. Invasive pulmonary pressure dropped from 57.5 ± 16.7 to 38.9 ± 13.5 (p < 0.001). A caval filter was implanted in 4 (5%) patients. The 1-year major adverse events and cardiovascular mortality rate was 4.0% and 1.4%, respectively. Access site complications (6 major and 6 minor) were encountered in 12 (16.2%) patients.Conclusions: Catheter directed thrombolysis in submassive pulmonary embolism had excellent results. However, additional mechanical thrombectomy was necessary in some patients to achieve good clinical outcomes

Periodic Membrane Potential and Ca2+ Oscillations in T Cells Forming an Immune Synapse

The immunological synapse (IS) is a specialized contact area formed between a T cell and an antigen presenting cell (APC). Besides molecules directly involved in antigen recognition such as the TCR/CD3 complex, ion channels important in the membrane potential and intracellular free Ca2+ concentration control of T cells are also recruited into the IS. These are the voltage-gated Kv1.3 and Ca2+-activated KCa3.1 K+ channels and the calcium release-activated Ca2+ channel (CRAC). However, the consequence of this recruitment on membrane potential and Ca2+ level control is not known. Here we demonstrate that the membrane potential (MP) of murine T cells conjugated with APCs in an IS shows characteristic oscillations. We found that depolarization of the membrane by current injection or by increased extracellular K+ concentration produced membrane potential oscillations (MPO) significantly more frequently in conjugated T cells than in lone T cells. Furthermore, oscillation of the free intracellular Ca2+ concentration could also be observed more frequently in cells forming an IS than in lone cells. We suggest that in the IS the special arrangement of channels and the constrained space between the interacting cells creates a favorable environment for these oscillations, which may enhance the signaling process leading to T cell activation