Transcranial doppler quantification of residual shunt after percutaneous patent foramen ovale closure: efficacy of the GORE(®) HELEX septal occluder.

Background: Ideally, percutaneous, mechanical closure of defects of the atrial septum should completely resolve shunt. To achieve this goal, more information is needed about the factors associated with device failure.

Methods: Consecutive patients with cryptogenic neurological events who had severe baseline Valsalva shunt (Spencer Grade 5-5+) and intracardiac echocardiography (ICE) defined patent foramen ovale (PFO) who underwent percutaneous PFO closure with the GORE(®) HELEX Septal Occluder device were evaluated for residual 3-month shunt by transcranial Doppler (TCD).

Results: We closed 315 PFO patients with the HELEX devices: 15, 20, 25, 30 mm devices in 19, 138, 150, and 8 patients, respectively. Severe residual Valsalva shunt (TCD Grade 5-5+) at 3 months occurred in 23 of 315 (7%) of all patients and in 2 of 108 (2%), 5 of 86(6%), and 16 of 121 (13%) patients with none, Grade 4, and Grade 5-5+ baseline rest shunt, respectively (P = 0.002). At 3 months, rest shunting was essentially abolished by closure. The percent of patients with severe residual Valsalva shunt was also related to device size: 15 mm (0%), 20 mm (4%), 25 mm (10%), and 30 mm (25%) (P = 0.008) and to atrial septal aneurysm. All of these variables were independent predictors of failure by multivariate logistic regression.

Conclusions: In an ICE-defined PFO population characterized by severe baseline Valsalva shunt and a high incidence of persistent (rest) shunting, the GORE(®) HELEX Septal Occluder device effectively reduces both provoked and persistent shunt. The causes of device failure are multifactorial. Larger devices perform less reliably suggesting the need for size-specific modifications to improve closure of more severe defects. (J Interven Cardiol 2011;24:366-372).