New technologyPerformance of Extracorporeally Adjustable Ventricular Assist Device Inflow CannulaDisclaimer
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Technology
This adjustable VAD inflow cannula was developed at the Cleveland Clinic (Cleveland, OH) to allow external adjustment of the cannula tip angle by using percutaneous mechanical cables (Fig 1). The junction of the intraventricular part of the inlet cannula and the rigid part connected to the VAD inlet port is composed of wire-reinforced flexible silicone rubber tubing to allow adjustments in the cannula tip angle. The angle formed between the pump body and the inflow cannula tip is adjusted using
Fitting Study
Four calf cadavers were used to evaluate various design concepts to prove feasibility of the adjustable inflow cannula. A stab puncture at the LV apex was made to insert the inflow cannula through a left fifth intercostal thoracotomy. The adjustable inflow cannula was connected to the Cleveland Heart left ventricular assist device (LVAD), inserted into the LV apex, and fixed to the heart by a polyester velour fabric inlet cannula cuff [6, 7]. The 2 remote-control cables connected to the
Fitting Study
We observed the remote-controlled inflow cannula directly (cases 1, 2, and 4; Fig 3) and with the fiberscope inserted from the left atrium (case 3). We confirmed that the cannula pointed in two different directions by remote control.
Short-Term Feasibility Study
Representative hemodynamic data recorded for one of the maximum cannula transitions from position 2 to 8 are listed in Table 1. The cannula position was changed from 2 to 8, then back to 2. At position 2, the LVAD flow was lower (4.8 L/min) than that at position 8,
Comment
This study demonstrated the effectiveness of an extracorporeally adjustable LVAD inflow cannula in an animal model. The ability to correct for low flow and ventricular suction events in a malpositioned or displaced inlet cannula was demonstrated, leading to increased LVAD support and more effective offloading of the LV. Various inflow cannula designs, modifying materials, cannulation sites, and the positioning within the ventricle have been previously attempted. A flexible inflow cannula with a
Disclosures and Freedom of Investigation
The authors independently developed this technology and had full control of the design of the study, methods used, outcome measurements, and production of the written report. Drs Saeed and Fukamachi are the inventors of this technology.
References (8)
- et al.
Influence of inflow cannula length in axial-flow pumps on neurologic adverse event rate: results from a multi-center analysis
J Heart Lung Transplant
(2008) - et al.
In vivo hemodynamic performance of the Cleveland Clinic CorAide blood pump in calves
Ann Thorac Surg
(2001) - et al.
Platelet activation, aggregation, and life span in calves implanted with axial flow ventricular assist devices
Ann Thorac Surg
(2002) - et al.
Development of a flexible inflow cannula with titanium inflow tip for the NEDO biventricular assist device
ASAIO J
(2004)
Cited by (4)
Cannula design
2018, Mechanical Circulatory and Respiratory SupportInvited commentary
2010, Annals of Thoracic SurgeryNumerical analysis of the effect of the design of axial-flow pump cannula tip on stagnation and recirculation zones in the left ventricle
2020, Vestnik Transplantologii i Iskusstvennykh Organov
- Disclaimer
The Society of Thoracic Surgeons, the Southern Thoracic Surgical Association, and The Annals of Thoracic Surgery neither endorse nor discourage use of the new technology in this article.