Transcatheter Aortic Valve Replacement in Patients With Pure Native Aortic Regurgitation:Results From a Multicenter Registry Study

Objective:Patients with untreated severe aortic regurgitation(AR)have a high risk of mortality.Transfemoral transcatheter aortic valve replacement(TF-TAVR)is a treatment option for AR;however,the safety and efficacy of this technique have not been sufficiently established.This study aimed to evaluate the clinical and anatomical variables correlating with device success of TF-TAVR using a self-expanding valve system for pure AR.Methods:Patients with pure native severe AR who underwent TF-TAVR using a self-expanding valve system were registered at 5 Chinese centers.The primary endpoint was device success at 1 month after TAVR.The secondary endpoint was the composite of major adverse cardiovascular events(MACE)at 6 months,including all-cause death,ischemic stroke,emergency conversion to cardiac surgery,and permanent pacemaker implantation.Echocardiography was used to analyze the left ventricular function before the TAVR procedure and during follow-up.Multivariable logistic regression and Cox regression analyses were performed to find relevant independent risk factors.Results:Between September 2019 and February 2022,79 patients with AR were enrolled in the study.At 1 month,device success was achieved in 60(75.9%)patients.By 6 months,29(36.7%)patients had MACE.Echocardiography revealed improved left ventricular function after TAVR.Multivariate regression analysis demonstrated that the Society of Thoracic Surgeons risk score(odds ratio 0.760,95%confidence interval(Cl):0.584-0.989;P=0.041)and annulus perimeter(odds ratio 0.888,95%Cl:0.796-0.992;P=0.035)were 2 predictors of device success.Moreover,annulus perimeter(<80.2mm),but not Society of Thoracic Surgeons risk score,was associated with a significant reduction in MACE at 6 months(hazard ratio 2.223,95%Cl:1.060-4.659;P=0.028).Conclusions:TF-TAVR using a self-expanding valve system appears to be a safe and feasible treatment for patients with pure native severe AR,particularly those with a less enlarged annulus.

Hemodynamic evaluation of different stent graft schemes in aortic arch covered stent implantation

Implantation of the left subclavian artery(LSA)stent graft used in fenestration technique of the thoracic endovascular aortic repair(TEVAR)may interfere with the aortic helical blood flow that is believed to have important protective functions against atherogenesis.The present study investigated four different LSA stent graft implantation schemes for their resulted blood flow patterns in the thoracic aortic with hemodynamic computational simulation methods:the flush branch(FB),the protruding branch(PB),the straight cuff branch(SCB)and the cured cuff branch(CCB).The results showed that the PB scheme could slightly enhance helicity of the swirling flow in the aorta,but the other three schemes had less effect on blood flow helicity.The PB scheme produced lowTAWSS,high-OSI and high-RRT around the LSA root,and the FB scheme had similar TAWSS,OSI and RRT in both value and distribution to those in the aorta without LSA stent graft implantation.The SCB and CCB schemes led to less area of high-OSI and high-RRT values along the walls of the LSA branch arteries.The results also showed that the PB scheme would significantly reduce blood supply to the LSA,on the contrary,the CCB scheme enhanced LSA blood supply and less effect on the total blood supply to the three branches of the thoracic aorta.In summary,all of the four schemes have no significant effect on the aortic swirling flow,however,in the terms of TAWSS,OSI,RRT and blood supply to the LSA,the CCB model might be the best option with less area of low-WSS,high-OSI,high-RRT and well blood supply in the LSA.