Periprocedural stroke risk in patients undergoing catheter ablation for atrial fibrillation on uninterrupted warfarin.

BACKGROUND: Catheter ablation is an effective treatment for symptomatic individuals with atrial fibrillation (AF) but is associated with a risk of periprocedual stroke. Recent data suggest that this risk may be abolished if catheter ablation is performed with uninterrupted warfarin (UW). We sought to compare the incidence, severity and timing of periprocedural stroke between 2 periprocedural anticoagulation protocols: bridging low-molecular-weight heparin (LMWH) and UW. METHODS AND RESULTS: Periprocedural stroke (≤14 days) was assessed in 2,855 ablations performed in 1,813 patients. Thromboembolic stroke occurred in 11/1,653 (0.7%) procedures with bridging LMWH and in 5/1,202 (0.4%) procedures on UW (P = 0.5). Four of the 5 strokes (80%) on UW occurred despite a therapeutic INR and a mean activated clotting time of ≥300 seconds and 4/5 strokes (80%) occurred in patients with a CHADS2 score of 0. Eleven of 16 (69%) strokes overall occurred within 24 hours of the procedure. All 4 strokes resulting in major neurological deficit occurred in the LMWH group. Major bleeding complications occurred in 6.0% of patients in the bridging LMWH group compared to 4.0% in the UW group (P = 0.02). CONCLUSIONS: In contrast to existing data, periprocedural stroke still occurs despite therapeutic anticoagulation throughout the operative period. The optimal strategy to protect patients against thromboembolic stroke remains unclear

The prevalence of low left atrial appendage emptying velocity and thrombus in patients undergoing catheter ablation for atrial fibrillation on uninterrupted peri-procedural Warfarin therapy

Introduction: The 2012 HRS/EHRA/ECAS guidelines encourage pre-procedural transesophageal echocardiography (TEE) prior to ablation for atrial fibrillation (AF), but acknowledge a lack of consensus in patients maintained on therapeutic warfarin before, during and after the procedure. This is partly because the incidence of left atrial appendage (LAA) thrombus is so low, that it is hard to draw clear conclusion regarding the characteristics of patients who develop thrombus. We hypothesize that the presence of low LAA emptying velocities, which predisposes to thrombus, and/or thrombus itself can be predicted in patients undergoing ablation, based upon clinical characteristics and transthoracic echocardiography (TTE). Methods: In this multicentre study, we undertook TTE and transesophageal echocardiograms (TEE) in 586 patients (age 59.9±0.4 years old, 64.5% male) undergoing catheter ablation for AF who were anticoagulated on warfarin (target international normalized ratio 2-3.5) for ≥3 consecutive weeks prior to procedure and maintained on warfarin for the procedure. Results: Low peak LAA emptying velocities (<40cm/s) were identified in 111 (24.7%) patients and LAA thrombus was identified in 3 patients (0.5%) despite having therapeutic INRs. The 3 patients with thrombus had LAA emptying velocities of 23, 29 and 31 cm/s. None of the remaining patients had a peri-procedural stroke. Patients with peak LAA emptying velocities <40cm/s or thrombus on TEE had significantly (p<0.05) higher CHA2DS 2-VASc scores (1.7± 0.1 v's 1.4±0.1), and were more likely to have impaired LVSF (odds ratio [95% CI]: 2.66 [1.52-4.66]), a LA diameter >4.6cm on TTE (2.40 [2.13-5.41]), or persistent AF (2.60 [1.63-4.14]) compared to those with a higher LAA velocity without thrombus. Conclusion: In patients on uninterrupted warfarin therapy, a CHA 2DS2-VASc score ≥1 or LA diameter >4.6cm on TTE identifies 91.5% of those at risk of developing thrombus with LAA emptying velocity of <40 cm/s and 100% of those with thrombus in our cohort

The Future of Work, Digital Labor, and Business Legitimacy

The increasing trend of Internet technology platforms and its offerings of digital labor have revolutionized the world of work. Companies that compete in this so-called gig economy are breaking away from traditional work arrangements and using a business model that challenges current employment and labor laws. While gig economy employers boast the benefit of work flexibility, their workers face compromised fairness in regard to compensation, working conditions, and career development. This chapter discusses how the gig economy redefines the future of work, by focusing on the current state of gig workers, and then explores opportunities for ways in which the gig economy can mutually benefit the employers and its workers