ADVERTISEMENT
Commentary
Patent Foramen Ovale and Atrial Septal Aneurysm: Achieving Closure
June 2009
The debate continues in the cardiology community over indications of percutaneous closure of patent foramen ovale (PFO) with or without an associated atrial septal aneurysm (ASA). Observational studies with control cohorts have shown an association between unexplained ischemic stroke and PFO. Hazard ratios for a stroke in the setting of a PFO range from 1.46–1.64.1,2 with an increase in the odds ratio of 3.9 for experiencing a cryptogenic stroke.3 An ASA alone or in combination with a PFO appears to increase the odds ratio of a paradoxical embolic stroke by 4.3 and 33.3, respectively.3 The latter was further underscored by a prospective European study in which the incidence of recurrent ischemic events (stroke or transient ischemic attack) despite appropriate antiplatelet therapy at 1 year was 3.7% and 3.0% with and without a PFO (6.2% and 5.6% at 4 years), respectively, but 5.9% at 1 year if a PFO was associated with an ASA (19.2% at 4 years).4
In this issue of the Journal, Musto et al compare the short- and long-term outcomes of PFO closure associated with an ASA using the Amplatzer Multi-Fenestrated Septal Occluder Cribriform (AMF) versus the Amplatzer PFO device (APO).5 ASA was defined as a localized protrusion of the fossa ovalis, with a base width ≥ 15 mm and septum excursion ≥ 10 mm into either atrium. Thirty-eight consecutive patients with PFO and ASA with at least 1 cryptogenic stroke were treated using the AMF device originally designed for fenestrated atrial septal defects (ASDs). The outcomes were compared to 38 patients treated with the APO device previously, with the same inclusion criteria, including concomitant PFO and ASA findings. All patients were treated with acetylsalicylic acid (300 mg) for 6 months. Device implantation occurred under ultrasound guidance and had 1-, 6- and 12-month clinical follow up, including examination and transthoracic echocardiography (TTE) at each visit, as well as TTE or transcranial Doppler at rest and with the Valsalva maneuver at 6 months for detection of right-to-left shunting (RLS). Procedural success was achieved in all patients in both groups, with only 3 patients in the APO group having residual post-procedural RLS. There were no associated deaths or significant complications in either group within the mean follow-up period of 13 and 25 months for AMF and APO, respectively. During this time period, three patients in the APO cohort experienced TIA at 6-month follow up (2 of whom had known small RLS immediately after implantation). The investigators conclude that the AMF (despite its equal disc size configuration) is a safe and effective transcatheter closure device for use in high-risk patients with a PFO associated with ASA compared to the APO device.
It is important to underscore the lack of randomized data to support the use of any percutaneous interventions for PFO closure over medical therapy alone. As the authors point out, this study was not randomized and has a small sample size. At 6 months, 2 of the 3 TIA events occurred in patients with suboptimal closure with the APO device. It is unclear if these devices were undersized in these cases or if there were other technical issues, but had the APO group also achieved total success in closure (e.g., no residual RLS immediately after implantation), then the long-term follow up between the devices might not have been any different. In addition, it is not clear how compliant the patients were in both groups with their antiplatelet therapies during the study.
A recently published prospective study6 reports 357 patients with cryptogenic stroke and PFO, 102 of whom also had an associated ASA, who underwent closure with either the Amplatzer (APO), Starflex or Helex occluder devices. Preprocedural RLS was abolished in 92% of all patients at 6 months, 95% at 1 year, 99% at 2 years and 100% at 5 years. For those patients with an associated ASA, full closure was achieved in 84% at 6 months, 90% at 1 year and 98% at 2 years. There was no statistically significant difference in closure time between the three different devices in either the PFO alone or PFO and ASA groups. The re-event rate in the entire patient population was 0.7% per year, with a trend favoring the Helex and Starflex over Amplatzer. There was no difference in event rate within the Starflex and Helex groups treated for PFO alone or PFO and ASA, but there was a statistically significant higher rate of repeat events in patients with a concomitant ASA treated with the Amplatzer as opposed to those treated for PFO alone with the same device.
From the latter discussion, it is evident that further studies are needed. Specifically, randomized, controlled clinical trials are necessary to better evaluate the benefit of percutaneous closure of PFOs with and without an associated ASA (with any device) over medical therapy alone. Ongoing clinical trials will help establish treatment guidelines for patients with atrial septal abnormalities and cryptogenic strokes.7
_______________________
From the University of California San Francisco, San Francisco, California.
The authors report no conflicts of interest regarding the content herein.
Address for correspondence: Victor Ochoa, MD, University of California San Francisco, Division of Cardiology, 505 Parnassus Avenue, Box 0103, San Francisco, CA 94143-0103. E-mail: vochoa@medicine.ucsf.edu
1. Meissner I, Khandheria BK, Heit JA, et al. Patent foramen ovale: Innocent or guilty? Evidence from a prospective population-based study. J Am Coll Cardiol 2006;47:440–445.
2. Di Tullio MR, Sacco RL, Sciacca RR, et al. Patent foramen ovale and the risk of ischemic stroke in a multiethnic population. J Am Coll Cardiol 2007;49:797–802.
3. Cabanes L, Mas JL, Cohen A, et al. Atrial septal aneurysm and patent foramen ovale as risk factors for cryptogenic stroke in patients less than 55 years of age. A study using transesophageal echocardiography. Stroke 1993;24:1865–1873.
4. Mas JL, Arquizan C, Lamy C, et al. Recurrent cerebrovascular events associated with patent foramen ovale, atrial septal aneurysm, or both. N Engl J Med 2001;345:1740–1746.
5. Musto C, Cifarelli A, Pandolfi C, et al. Transcatheter closure of patent foramen ovale associated with atrial septal aneurysm with Amplatzer cribiform septal occluder. J Invasive Cardiol 2009;21:291–294.
6. von Bardelebena RS, Richter C, Otto J, et al. Long-term follow up after percutaneous closure of PFO in 357 patients with paradoxical embolism: Difference in occlusion systems and influence of atrial septum aneurysm. Int J Cardiol 2009;134:33–41.
7. Thaler DE, Saver JL. Cryptogenic stroke and patent foramen ovale. Curr Opin Cardiol 2008; 23:537–544.
