A novel biodegradable patent foramen ovale (PFO) closure device, which fully degrades within 24 months following implantation, demonstrated noninferiority to the conventional nitinol device for both effectiveness and safety, according to a randomized controlled trial published Oct. 13 in Circulation.

Fengwen Zhang, MD, PhD, et al., randomly assigned 190 adult patients (mean age, 42 years; 70% women) with PFO to receive the biodegradable device (n=96) or the nitinol device (n=94) at seven hospitals in China between February and July 2021.

Efficacy results showed that the majority of patients in both groups (91% and 92%, respectively) attained successful PFO closure at six months postoperatively.

Noninferiority of the biodegradable device to the nitinol device for successful closure was determined based on the lower limit of the 95% CI of absolute difference being larger than the established noninferiority margin (−8.98% vs. −10%, respectively).

Notably, assessment of right-to-left shunt (RLS) at 24 months showed that RLS grade 0 (no microbubbles) or 1 (one to 10 microbubbles) occurred in 95% of patients with the bioabsorbable device and 92% of the control group, with no statistically significant difference between groups. In other findings, the bioabsorbable device consistently achieved lower residual RLS rates at both six (9.37%) and 24 (5.21%) months, which aligns with previous studies.

Safety findings revealed that no deaths, embolism, device thrombus, erosion or other severe complications occurred in either group during the entire study. One patient with a biodegradable device experienced intraprocedural deformation requiring surgical device removal.

Importantly, transthoracic echocardiography showed that the hyperechoic region corresponding to the biodegradable device began decreasing within 12 months after implantation and disappeared by 24 months following implantation.

Although the current study confirmed that “the biodegradable PFO closure device provides an effective and safe treatment option,” Zhang and colleagues write that “the relatively short follow-up duration and limited sample size … necessitate additional large-scale studies to comprehensively assess the long-term safety profile” of the device.