Cerebral Microembolization During Aortic Valve Replacement Using Minimally Invasive or Conventional Extracorporeal...

Area of Science:

• Cardiovascular Surgery
• Neurology
• Biomedical Engineering

Background:

• Minimally invasive extracorporeal circulation (MiECC) aims to reduce patient trauma during cardiac surgery.
• Cerebral microembolism is a concern in extracorporeal circulation, potentially impacting neurological outcomes.
• Surgical aortic valve replacement (SAVR) is a common procedure where extracorporeal circulation is employed.

Purpose of the Study:

• To compare intraoperative cerebral microembolic load between MiECC and conventional extracorporeal circulation (CECC) during isolated SAVR.
• To evaluate the impact of oxygenators with integrated arterial filters on microembolic load in MiECC.
• To determine if MiECC is non-inferior to CECC in terms of cerebral microembolism during SAVR.

Main Methods:

• A randomized trial comparing MiECC and CECC in patients undergoing elective SAVR.
• Primary outcome: rate of high-intensity transient signals (HITS) on transcranial Doppler ultrasound during specific procedural phases.
• Analysis included 45 patients due to signal loss, with subgroups for MiECC/CECC with or without arterial filters.

Main Results:

• MiECC demonstrated a significantly higher HITS rate (1.75 times) compared to CECC.
• Increased HITS rates in MiECC were observed during phases from aortic cross-clamping to declamping and from declamping to cessation of perfusion.
• Post hoc analysis indicated MiECC without an arterial filter generated higher HITS rates than CECC with filters.

Conclusions:

• MiECC is not superior to CECC regarding gaseous cerebral microembolism during open-heart surgery like SAVR.
• The use of oxygenators with integrated arterial line filters is strongly advised when employing MiECC for SAVR.
• With an integrated filter, MiECC can achieve a comparable cerebral microembolic load to CECC during SAVR.