Evaluation of endothelialization of an occluder device with cardiac computed tomography and assessment of the pathological validation

Background: Assessing the endothelialization of occlusive devices noninvasively remains a challenge. Cardiac computed tomography angiography (CTA) can be employed to evaluate device endothelialization based on contrast uptake within the occluder.

Objective: This study examined device endothelialization using cardiac CTA and investigated the pathological associations.

Methods: From January 2010 to May 2022, we retrospectively analyzed 25 patients (age: 50.00 [17.00, 52.00] years; 12 Female) who underwent surgical device removal within 1 month after cardiac CTA examination (implantation period: 29.00[0.50, 108.00] months). The contrast uptake within the occluder was determined using cardiac CTA. The relationship between contrast uptake within the occluder and the endothelialization status with pathology was analyzed.

Results: Contrast uptake within the occluder was identified in 76.00% of patients. Pathological examination confirmed incomplete coverage of fibrotic tissue and superposed neoendothelium on the surface of all devices exhibiting contrast uptake. This included no coverage in 47.37% of patients and partial coverage in the remaining cases. On the surface of all devices without contrast uptake, a complete range of fibrotic tissue was observed, with an incomplete range of superposed neoendothelium in 66.67% of patients. On the surface of devices with an implantation period > 6 months, 71.43% of patients had incomplete coverage of fibrotic tissue and superposed neoendothelium on the left disc, 42.86% of patients occurred the same on the right disc.

Conclusions: Contrast uptake within the occluder indicated incomplete endothelialization, as confirmed by pathological validation. Late endothelialization of the device occurs frequently, and further research is required to investigate related mechanisms.