The occluder comes in three sizes (22, 27, and 32 mm). As with other devices, size selection is based upon measurements performed at 0, 45, 90, and 135° on transesophageal echocardiogram (TEE). The smallest device size is chosen so that the longest measured diameter does not exceed the nominal device size and the average of the longest and shortest diameters is at least 3 mm below the nominal device size. The sizing table is included in the instructions for use and is unique to other LAA occluder devices in that it incorporates both the short and long axis of the LAA in the sizing strategy (Fig. 16.2).

Implantation of the Coherex WaveCrest LAA Occluder is shown in Fig. 16.3. The optimal landing zone is determined by the line of widest measurement of the ostium, using the circumflex artery medially and a point at least 10–15 mm into the LAA from the tip of the lateral edge for reference, leaving room distally for the anchors to deploy. The landing zone is generally more proximal than other devices, which is meant to allow treatment of proximal lobe bifurcations and acutely angulated appendages. Distal injection is a unique feature of this device that allows visualization of contrast extravasation to assess leak.

The device was first implanted in June 2012. The first results of the device were presented by Dr. Vivek Reddy at Congenital and Structural Interventions (CSI) 2013, with successful deployment in 96 % of patients (n = 73); 45-day data showed primary efficacy of 92 and 97 % with an intention-to-treat and as-treated protocol, respectively. The total major adverse event rate was 2.7 %, consisting of two pericardial effusions treated by percutaneous drainage. There were no reports of stroke, device embolization, or associated thrombus. One-year follow-up will conclude in August 2014.

CE Mark was obtained in 2013. Next steps include a US investigational device exemption (IDE) trial with plans for start of enrollment in the end of 2014.