Date on Master's Thesis/Doctoral Dissertation

12-2013

Document Type

Master's Thesis

Degree Name

M. Eng.

Department

Bioengineering

Committee Chair

Koenig, Steven Christopher

Author's Keywords

Sutureless implantation; Aortic valve bypass; Left ventricular cannulation; Cannula system

Subject

Heart--Surgery; Coronary artery bypass

Abstract

Introduction: Cannulation of the left ventricle (LV) apex is a common surgical procedure for aortic valve bypass and ventricular assist device (VAD) implantation. LV cannulation requires coring of the LV apex and attaching a sewing ring via suture. Although effective, suturing is time-consuming and apical coring can lead to bleeding complications or inflow occlusion. The scope of this project was to design a sutureless-anchoring device for an apical left ventricular (ALV) cannula system. Instrumentation, equipment, and procedures: The sutureless-anchoring device was designed as a conical spring. Five prototypes were fabricated with varying wire diameter (0.045”-0.055”), maximum cone diameter (0.85”-0.975”), and spring height (0.75”-1.25”). The conical springs were attached to PVC cylinders to mimic ALV cannulae. The prototypes were tested through 1) leak test with pressurized porcine hearts, 2) tensile pull test using porcine hearts and an INSTRON, and 3) quantitative assessment of device implantation by cardiothoracic surgeons. Results and Discussion: Leak testing determined that the prototypes created a leak-proof tissue-cannula interface. The prototype with the largest cone and wire diameter combination was able to achieve a tensile failure force similar to that of a clinically-used VAD sewing ring. Other prototypes yielded failure forces below the VAD sewing rings. The quantitative assessment reported that the prototype easily penetrates the tissue and is quicker to implant than sewing rings. Conclusions: This preliminary study demonstrated promise for a sutureless-anchoring device as part of an ALV cannula system. A sutureless implantation method may lead to safer and faster LV cannulation surgeries, thus improving patient outcomes and reducing surgical cost. Recommendations: It is recommended to test springs with larger wire diameter and large end outer diameter combinations than those tested in this study. It is also recommended to create and test multiple prototypes of each variation of spring dimensions.

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