Comparison of the size of persistent foramen ovale and atrial septal defects in divers with shunt-related decompression illness and in the general population.

INTRODUCTION: Decompression illness (DCI) is associated with a right-to-left shunt, such as persistent foramen ovale (PFO), atrial septal defect (ASD) and pulmonary arteriovenous malformations. About one-quarter of the population have a PFO, but considerably less than one-quarter of divers suffer DCI. Our aim was to determine whether shunt-related DCI occurs mainly or entirely in divers with the largest diameter atrial defects. METHODS: Case control comparison of diameters of atrial defects (PFO and ASD) in 200 consecutive divers who had transcatheter closure of an atrial defect following shunt-related DCI and in an historic group of 263 individuals in whom PFO diameter was measured at post-mortem examination. RESULTS: In the divers who had experienced DCI, the median atrial defect diameter was 10 mm and the mean (standard deviation) was 9.9 (3.6) mm. Among those in the general population who had a PFO, the median diameter was 5 mm and mean was 4.9 (2.6) mm. The difference between the two groups was highly significant (P < 0.0001). Of divers with shunt-related DCI, 101 (50.5%) had an atrial defect 10 mm diameter or larger, but only 1.3% of the general population studied had a PFO that was 10 mm diameter of larger. CONCLUSIONS: The risk of a diver suffering DCI is related to the size of the atrial defect rather than just the presence of a defect.

Migraine Intervention With STARFlex Technology (MIST) trial: a prospective, multicenter, double-blind, sham-controlled trial to evaluate the effectiveness of patent foramen ovale closure with STARFlex septal repair implant to resolve refractory migraine headache.

BACKGROUND: Patent foramen ovale (PFO) is prevalent in patients with migraine with aura. Observational studies show that PFO closure resulted in migraine cessation or improvement in approximately 80% of such patients. We investigated the effects of PFO closure for migraine in a randomized, double-blind, sham-controlled trial. METHODS AND RESULTS: Patients who suffered from migraine with aura, experienced frequent migraine attacks, had previously failed > or = 2 classes of prophylactic treatments, and had moderate or large right-to-left shunts consistent with the presence of a PFO were randomized to transcatheter PFO closure with the STARFlex implant or to a sham procedure. Patients were followed up for 6 months. The primary efficacy end point was cessation of migraine headache 91 to 180 days after the procedure. In total, 163 of 432 patients (38%) had right-to-left shunts consistent with a moderate or large PFO. One hundred forty-seven patients were randomized. No significant difference was observed in the primary end point of migraine headache cessation between implant and sham groups (3 of 74 versus 3 of 73, respectively; P=0.51). Secondary end points also were not achieved. On exploratory analysis, excluding 2 outliers, the implant group demonstrated a greater reduction in total migraine headache days (P=0.027). As expected, the implant arm experienced more procedural serious adverse events. All events were transient. CONCLUSIONS: This trial confirmed the high prevalence of right-to-left shunts in patients with migraine with aura. Although no significant effect was found for primary or secondary end points, the exploratory analysis supports further investigation. The robust design of this study has served as the model for larger trials that are currently underway in the United States and Europe.

BioSTAR Evaluation STudy (BEST): a prospective, multicenter, phase I clinical trial to evaluate the feasibility, efficacy, and safety of the BioSTAR bioabsorbable septal repair implant for the closure of atrial-level shunts.

BACKGROUND: The use of permanent synthetic implants to close atrial septal defects (ASD) and patent foramen ovale (PFO) has a number of limitations, including late complications and the limiting of transeptal access to the left heart should it be required for the later treatment of acquired heart disease. BioSTAR is a novel, bioabsorbable, atrial septal repair implant. This phase I pilot study evaluates the feasibility, safety, and effectiveness of BioSTAR for the first time in humans. METHODS AND RESULTS: We conducted a prospective, open-label, multicenter clinical study in 58 patients aged 28 to 68 years who had a clinically significant ASD or PFO. Percutaneous shunt closure was undertaken with the BioSTAR septal repair implant. Successful device implantation was achieved in 57 (98%) of 58 patients. Closure at 30 days and 6 months, assessed by contrast transthoracic echocardiography, was 48 (92%) of 52 and 54 (96%) of 56, respectively. There was no evidence of a clinically significant response to the device. Transient atrial arrhythmia occurred in 5 patients after implantation. No major safety issues were observed. CONCLUSIONS: This study demonstrates the feasibility, safety, and effectiveness of BioSTAR for the closure of ASD and PFO in humans with a high rate of early and complete shunt closure. BioSTAR is a novel septal repair implant designed to provide biological closure of atrial-level defects using the patient's natural healing response. Because 90% to 95% of the implant is absorbed and replaced with healthy native tissue, future access to the left atrium may be achieved.