Comment:
The results of our study demonstrate a high frequency of debris captured
within surgical sponges placed in the left ventricle prior to aortic
valve leaflet removal and annulus debridement. 75% of the sponges used
in these procedures had some form of cellular or acellular debris
contained within them on examination. 35% of sponges were grossly
positive, 75% were radiographically positive, and 25% were
histologically positive for calcified debris. The discrepancy between
radiographic and histologic detection of calcified debris likely results
from loss of the specimen during transfer or from under sampling the
blocks from which microscopic slides are made. Alternatively, specimens
may also contain surgical debris that is not mineralized. The results of
this study are certainly encouraging with respect to this specific
technique. However, this study was not designed to understand the
possible clinical implications of embolization of the captured debris
into systemic circulation. It is unclear if, for example, embolization
of debris that is only able to be detected radiographically or
histologically would have resulted in clinically significant
complications for the patient. More data is needed to fully appreciate
this relationship. Additionally, because calcified debris does not
maintain its shape when cut for microscopic sections, our current
methodological design cannot reliably estimate embolus size, though
observed calcified debris ranged from 0.1 mm through 0.33 mm (Figure 3).
However, we believe that consensus among practicing Cardiac Surgeons
would support decreasing calcified debris of any size as a beneficial
outcome for the patient.
This is the first published study aimed at objectively evaluating the
efficacy of a technique for decreasing intravascular calcified debris in
surgical aortic valve replacement. While the data in this
proof-of-concept study is promising with respect to this technique,
numerous additional techniques exist across practices and centers aimed
at the same purpose. Given the devastating nature of these
complications, the individual and relative efficacy of the prevention
techniques should be objectively evaluated, compared, and a best
practice standard should be developed for use across the specialty. To
this end, additional data and multi-center collaboration is required.