Minimally invasive cardiac surgery (MICS) has become an essential approach for reducing trauma, recovery time, and complications compared to traditional open-heart surgery. However, achieving effective caval isolation for cardiopulmonary bypass (CPB) in MICS presents significant challenges, particularly in patients with hypertensive or dilated atria. The Aulus venous cannula, developed as a novel alternative, aims to simplify this process while improving patient safety and procedural efficiency.
Key Innovations of the Aulus Cannula
The Aulus venous cannula integrates heparin coating and dual inflatable balloons to block blood flow in the superior and inferior vena cava without requiring external manipulation. Traditional methods rely on vessel dissection and encirclement with occlusive bands, increasing the risk of bleeding and complications. By eliminating these steps, the Aulus cannula minimizes surgical trauma and improves procedural precision.
Preclinical Testing and Safety Evaluation
A comprehensive preclinical evaluation was conducted, including:
- In-vitro Bench Testing: The cannula pressure drop remained below the hemolytic threshold of 100 mmHg, ensuring safe blood flow.
- Ex-vivo Porcine Heart Model: The cannula achieved full caval occlusion, confirmed via endoscopic visualization, and demonstrated precise placement.
- Large Animal Study: Conducted on ovine models, the study divided animals into short-term (7 days) and long-term (90 days) groups to assess safety and histopathological impact.
Results showed effective anticoagulant activity, with no significant deviations in CPB performance between the test and control groups. Short-term evaluations revealed mild vessel injuries, while long-term analysis indicated fibrosis-related stenosis without major thrombotic events.
Clinical Implications and Future Directions
The Aulus cannula demonstrated strong potential for MICS applications by reducing vessel trauma, enhancing CPB performance, and ensuring reliable caval occlusion. Future research should focus on large-scale clinical trials to validate its effectiveness in human patients, optimizing its design for broader surgical applications.
By addressing long-standing challenges in venous cannulation for MICS, the Aulus cannula could significantly improve procedural safety, reduce operative time, and enhance patient outcomes.
