MINIMALLY INVASIVE AORTIC VALVE SURGERY WITH VENOUS WALL-LESS CANNULAS: PERFORMANCES AND SAFETY PROFILE

Introduction: Techniques for venous cannulation during aortic minimally invasive surgery (MICS) evolved significantly. Aim of this study is to report the institutional experience with virtually wall-less venous cannulas during MICS aortic surgery. Methods: Transfemoral venous cannulation with Smart cannulas was performed in consecutive patients undergoing aortic MICS (isolated or in combination with other procedures). Target venous flow drainage (2.4 L/mq, Cardiac Index) and maximal suction performance without vacuum assistance were measured along with complications. Results: Since 2017, the Smartcannula was successfully positioned in all 75 patients (65.3 ± 11.8 years, 56 males) undergoing aortic MICS. The size measured 680 mm in length was adopted in all but two patients, who received the 530 mm Smartcannula. Regarding the surgical access, it was a superior mini-sternotomy in 75 patients (57 AVR, 10 bio-Bentall, 8 isolated ascending aorta and hemi-arch replacement). For a body height of 169.22 ± 24.83 cm and a body weight of 80.55 ± 15.21 kg, the calculated body surface area was 1.93 ± 0.22 mq. Expected target flow of 4.63 ± 0.53, whereas the achieved flow accounted for 5.85 ± 0.88 l/min (increase of 19.79%, in respect to target flow) without adopting vacuum, in all cases. Conclusion: The performance of self-expanding smart cannulas for venous drainage during aortic MICS proved to be extremely satisfactory, with a high safety profile. The drainage is optimal without vacuum in this setting, suggesting a steady superior flow over traditional rigid wall cannulas and confirming the efficacy during their routinary use.