Atrial versus ventricular cannulation for a rotary ventricular assist device

Area of Science:

• Cardiovascular Engineering
• Biomedical Engineering
• Medical Devices

Background:

• The inflow cannulation site of ventricular assist devices (VADs) is critical for patient interface.
• Connecting VAD cannulae to the atria or ventricles significantly alters flow dynamics, but quantification is limited.

Purpose of the Study:

• To quantify hemodynamic differences between atrial cannulation (AC) and ventricular cannulation (VC) in a rotary left VAD.
• To evaluate these differences across various left heart failure conditions using a mock circulation loop.

Main Methods:

• Utilized a mock circulation loop simulating a rotary left VAD.
• Simulated a range of left heart failure conditions.
• Quantified ventricular/vascular hemodynamics, including ejection fraction (EF), stroke work, and pump flow rates for both AC and VC.

Main Results:

• Ventricular ejection fraction (EF), stroke work, and pump flow rates were consistently lower with AC compared to VC.
• AC maintained adequate ventricular ejection under low support but showed reduced EF in severe heart failure, potentially increasing thromboembolic risk.

Conclusions:

• Ventricular cannulation (VC) offers better hemodynamic support than atrial cannulation (AC) for left VADs.
• AC is suitable for less severe heart failure (Class III, bridge to recovery), while VC is better for severe cases (Class IV, bridge to transplant/destination).