Fundamentals: Etiology of cryptogenic stroke stills a major challenge for medicine. Paradoxical embolism remains one of the possible causes. Undoubtedly, adults between 20 and 54 years represent a significant proportion of this population, and this is associated with a high morbidity and high costs not only in relation to the pathology itself but also to the recovery and rehabilitation of individual. In this sense, the closure of patent foramen oval (PFO) could be an element that prevents paradoxical embolism and may decrease the incidence of new events in this population.
Conclusiones: Methods and Results: This is a Canadian study, randomized 1:1, conducted in 69 centers for a long of eight years to reach the events (reached 25 events). Placing of Amplatzer vs. clinical treatment was randomized.
We selected a population between 18-60 years with well-defined stroke and confirmed by CT or MRI in the last 270 days pre-enrollment in the study. We excluded stroke of other etiology, as well as those with contraindications for antiplatelet therapy and / or carriers of anatomic variations that might hinder the implantation of the device. Primary endpoint was the occurrence of fatal and nonfatal stroke and mortality. The secondary endpoints included complete closure of PFO and the absence of transient stroke.
We selected 980 patients without differences in their demographics. There were no technical complications in device implantation in 499 patients and the success rate was 95%. Clinical follow-up was longer in patients who received the device (2% vs 1.9%) with a smaller number of subjects who were lost to follow up (48 patients withdrew consent in the FO closure group vs. 90 in the control group).
An analysis by ITT patients showed a 63.4% reduction in the risk of new stroke in the group receiving percutaneous treatment. Of the nine events in the treatment group, 3 had not yet received implant (only received clinical treatment). If not considered further improve the result: 72.7% of reduction in risk of new stroke (p = 0.0067). This reduction is increasing over time if we analyze the number of patients needed to treat to avoid closing FO to avoid new stroke: 250 after 1 year, 70 after two years and 23 after 5. In subgroup analysis, shunt patients and atrial septal aneurysm are those who had the greatest benefits.
Conclusions: RESPECT study showed that in selected patients with a history of cryptogenic stroke patent foramen oval closure with Amplatzer prosthesis is beneficial in relation to clinical treatment.
Editorial Comment: Interesting design as always with competitive trials because it gives them a great dynamic to trial. Its major drawback was the time it took to collect the information that we are now discussing.
John Carroll
2012-10-25
Original title: RESPECT: A Prospective, Randomized Trial of PFO Closure vs. Medical Therapy in Patients with Cryptogenic Stroke
