Changes in cerebral oxygen saturation during transcatheter aortic valve replacement

Area of Science:

• Cardiology
• Neurology
• Anesthesiology

Background:

• Cerebral oxygen saturation (rSO2) monitoring is crucial for assessing cerebral oxygen balance and perfusion.
• A decrease in rSO2 >20% from baseline is linked to cerebral ischemia and increased perioperative morbidity.
• Transcatheter aortic valve replacement (TAVR) necessitates hemodynamic manipulation, including rapid ventricular pacing, potentially impacting cerebral oxygenation.

Purpose of the Study:

• To investigate the changes in cerebral oxygen saturation (rSO2) during transcatheter aortic valve replacement (TAVR).
• To assess the magnitude and duration of rSO2 changes during the ventricular pacing required for TAVR valve deployment.

Main Methods:

• A prospective case series of ten ASA IV patients undergoing TAVR under general anesthesia.
• Cerebral oximetry values were recorded at four key time points: pre-procedure (baseline), post-intubation, during valve deployment, and at procedure end.
• Analysis focused on the percentage change in rSO2 relative to baseline and post-induction values.

Main Results:

• Baseline rSO2 was 54.5 ± 6.9%. Post-induction, rSO2 increased to 66.0 ± 6.7%.
• During valve deployment, mean rSO2 decreased to 48.5 ± 13.4% (a <20% drop from baseline), but two patients had >20% desaturation.
• Cerebral oxygenation returned to post-induction levels within 13 ± 10 minutes after valve deployment.

Conclusions:

• Rapid ventricular pacing during TAVR is associated with a significant decrease in rSO2 compared to post-induction values.
• Despite increased post-induction rSO2, some patients experienced significant desaturation, suggesting potential benefits from maximizing rSO2 prior to manipulation.
• Further research is needed to correlate rSO2 recovery with hemodynamic recovery and optimize strategies for maximizing and rapidly restoring cerebral oxygenation during TAVR.