Transcatheter aortic valve implantation:Current status and future perspectives

Although surgical aortic valve replacement is the standard therapy for severe aortic stenosis(AS),about one third of patients are considered inoperable due to unacceptable surgical risk.Under medical treatment alone these patients have a very poor prognosis with a mortality rate of 50%at 2 years.Transcatheter aortic valve implantation(TAVI)has been used in these patients,and has shown robust results in the only randomized clinical trial of severe AS treatment performed so far.In this review,we will focus on the two commercially available systems:Edwards SAPIEN valve and CoreValve Revalving system.Both systems have demonstrated success rates of over 90%with 30-d mortality rates below 10%in the most recent transfemoral TAVI studies.Moreover,long-term studies have shown that the valves have good haemodynamic performance.Some studies are currently exploring the non-inferiority of TAVI procedures vs conventional surgery in high-risk patients,and long-term clinical results of the percutaneous valves.In this article we review the current status of TAVI including selection of patients,a comparison of available prostheses,results and complications of the procedure,clinical outcomes,and future perspectives.

Percutaneous closure of patent foramen ovale: “Closed” door after the last randomized trials?

Patent foramen ovale(PFO) percutaneous closure has previously been an accepted intervention for the prevention of recurrent cryptogenic stroke on the basis of observational studies. However, randomized trials have been lacking until now. Three recently published randomized trials(CLOSURE I, PC and RESPECT) do not demonstrate the superiority of this intervention versus optimal medical therapy, therefore making this practice questionable. Nonetheless, these trials have had certain pitfalls, mainly a lower than initially estimated number of patients recruited, therefore lacking sufficient statistical power. On the other hand, different closure devices were used in the three trials. In two of them(PC and RESPECT), the Amplatzer PFO Occluder was used and the STARflex device was used in the other one(CLOSURE I). Taken altogether, a meta-analysis of these three trials does not demonstrate a statistically significant benefit of percutaneous PFO closure(1.9% vs 2.9%; P = 0.11). However, if we analyze only the PC and RESPECT trials together, in which the Amplatzer PFO Occluder was used, a statistically significant benefit of percutaneous PFO closure is observed(1.4% vs 3.0%, P = 0.04). In conclusion, our interpretation of these trials is that the use of a dedicated, specifically designed Amplatzer PFO device could possibly reducethe risk of stroke in patients with PFO and cryptogenic stroke. This consideration equally applies to patients who have no contraindications for anticoagulant or antithrombotic therapy.

Percutaneous treatment in acute coronary syndromes

Both ST-segment elevation myocardial infarction and non-ST-segment elevation acute coronary syndromes (ACS) are the result of an acute thrombotic lesion obstructing blood flow in the coronary vasculature. Percutaneous treatment has shown to improve clinical outcome in this clinical setting by resolving coronary obstruction with different devices directed to restore coronary blood flow. In comparison with balloon alone angioplasty, implantation of bare metal stents reduced the rate of restenosis and cardiac events, but high rates of restenosis remained, leading to further investigations to develop drug-eluting stents with different pharma- cological coatings that reduced restenosis rates and clinical events. In this review, we discuss the current treatment of ACS, reviewing recent randomized clinical trials and advances in medical treatment, including new antiplatelet agents and recent guideline recommendations.