Embolic material generated by multiple aortic crossclamping: a perfusion model with human cadaveric aorta.

Area of Science:

• Cardiovascular Surgery
• Neurology
• Biomaterials Science

Background:

• Atherosclerosis of the ascending aorta and aortic crossclamping are known risk factors for neurologic injury in cardiac surgery.
• Repeated aortic manipulation is integral to most cardiac surgical procedures.

Purpose of the Study:

• To quantify the amount and size of particulate matter dislodged from the aortic wall due to repeated aortic crossclamping.
• To assess the embolic potential of material released during aortic manipulation.

Main Methods:

• The study utilized autopsy specimens from 10 subjects, with the aorta dissected and mounted in a perfusion model.
• The ascending aorta was subjected to 10 cycles of crossclamping and washout, with perfusate collected and analyzed.
• Computerized image processing was employed for macroscopic and microscopic examination of calcified and cellular particulate matter.

Main Results:

• Aortic crossclamping generated substantial particulate matter, with initial procedures yielding the highest output.
• The number of particles decreased with repeated crossclamping, approaching baseline levels by the 6th to 10th washout (P =.012).
• Particles ranged in size up to 4.74 mm, with microscopic analysis revealing both calcified and noncalcified cellular debris.

Conclusions:

• Dislodged material from aortic crossclamping possesses significant embolic potential, particularly noncalcified cellular debris.
• While repeated crossclamping reduces particle release, initial manipulations pose a considerable embolic risk.
• These findings challenge surgical techniques involving repeated aortic crossclamping and highlight the need for embolic risk mitigation.