Low-flow perfusion technique for shaggy aortic arch

The most common complication of thoracic aortic disease with shaggy aorta is cerebral infarction. We have performed "low-flow perfusion" as a method of extracorporeal circulation to prevent cerebral embolism in patients with strong atherosclerotic lesions in the aortic arch.

"Low-flow perfusion" is a method in which cardiopulmonary bypass is started by partial blood removal, approaching deep hypothermia while maintaining self-cardiac output. We compared the outcomes of 12 patients who underwent the "low-flow perfusion" method (Group L) with those of 12 who underwent normal extracorporeal circulation (Group N) during aortic arch surgery since 2019.

Group L consisted of 8 males with an average age of 73 years old, and Group N consisted of 6 males with an average age of 73 years old. The average time from the start of cooling to ventricular fibrillation was 9.5 min in Group L and 3.6 min in Group N (p < 0.01). The eardrum temperature when ventricular fibrillation was reached was 28.2 °C in Group L and 32.5 °C in Group N (p = 0.01). A blood flow analysis also revealed low wall shear stress on the lesser curvature of the aortic arch.

With this method, the intracranial temperature was sufficiently low at the time of ventricular fibrillation, and there was no need to increase the total pump flow. The low-flow perfusion method can prevent cerebral embolism by preventing atheroma destruction by the blood flow jet while maintaining the self-cardiac output during the cooling process.