Development of a new selective coronary perfusion cannula

Area of Science:

• Cardiovascular Surgery
• Medical Device Engineering
• Perfusion Technology

Background:

• Current coronary perfusion cannulae, including balloon and fenestrated types, can lead to high perfusion pressures or significant leakage during cardioplegic solution infusion.
• Addressing these limitations is crucial for optimizing myocardial protection during cardiac surgery.

Purpose of the Study:

• To evaluate the performance of a newly developed Kochi Medical School (KMS)-type coronary perfusion cannula.
• To compare the KMS-type cannula against traditional balloon and fenestrated types in an ex vivo model.

Main Methods:

• An ex vivo experimental model with varying ostium sizes (4, 3, 2 mm) was used.
• Ejected flow velocity, circuit pressure, and leakage were measured at infusion rates of 100 and 200 mL/min.
• Measurements were taken under zero and 50 cmH2O counterpressure to simulate different coronary vascular resistances.

Main Results:

• The balloon type exhibited high flow velocity and pressure but no leakage.
• The fenestrated type demonstrated substantial leakage, particularly with smaller ostia.
• The KMS type showed lower flow velocity and pressure with reduced leakage.
• Crucially, only the KMS-type cannula successfully infused fluid into all ostium sizes under counterpressure.

Conclusions:

• The KMS-type coronary perfusion cannula demonstrates superior performance in minimizing leakage and ensuring secure cardioplegic solution delivery.
• Its design may be advantageous for achieving effective myocardial perfusion in patients with diseased coronary ostia.