Impact of Root Venting on Brain Injury in Minithoracotomy Aortic Valve Replacement: Prospective Evaluation With Preoperative and Postoperative Brain MRI in 252 Patients.

Abstract

The predominant method for preventing cerebral infarction secondary to air embolism in cardiac surgery is the use of root vents to remove air. However, in the case of minimally invasive aortic valve replacement (MIAVR) surgery, the risk of air embolism is lower compared with other types of minimally invasive cardiac surgery, and some surgeons routinely forgo root venting. This study sought to quantify how much difference root venting makes in stroke and asymptomatic brain injury (ABI) incidence in MIAVR. The study enrolled patients undergoing elective MIAVR from January 2016 to March 2023 at 1 hospital. The patients were categorized into groups, with (R group) and without root venting (N group). All patients underwent brain magnetic resonance imaging, including diffusion-weighted imaging, 1 day preoperatively and 5 days post operatively. The R and N groups consisted of 126 cases each. ABI incidence was significantly greater in the N group (46% vs 31%; P < .05). Only 1 patient in the entire cohort sustained a stroke (R group). The incidence of ABI was not significantly different among different sites of cannulation over all patients. However, the incidence of ABI was significantly lower in the R group than in the N group for patients whose cannulation site was the femoral artery. Deairing with a root vent resulted in fewer ABIs even in MIAVR. However, given that ABI is asymptomatic, the tradeoff between prevention of ABI and surgical simplicity should be considered.