Date of Award


Document Type

Thesis - SCU Access Only


Santa Clara University


SentreHEART, an innovator in catheter technology for tissue closure, has built a device to ligate the left atrial appendage. This device is a noninvasive instrument that utilizes a balloon catheter-based system that only requires a small needle access instead of open heart surgery. The left atrial appendage has been known to cause be a location of thrombus formation in patients with atrial fibrillation, the most common form of heart arrhythmia. Fifteen percent of those who have had strokes have also had atrial fibrillation Needle access is made in the patient and the catheter is fed through the vein with a guide wire. A balloon filled with fluorescent contrast is fed along the guide wire, positioned at the appendage, and then inflated to signify the location of the catheter. On the outside of the left atrial appendage, a separate guide wire with the LARIAT Suture Delivery Device, which is comparative to a lasso, is fed through another needle access site until it meets the existing guidewire within the appendage. Both guidewires are then connected using the FindrWIRZ Magnetic Guide Wire System. The connection is accomplished magnetically with magnets that are located at the end of both guidewires. The balloon is then inflated once more and then the surgeon wraps the suture around the left atrial appendage and inflated balloon, which then successfully ligates the left atrial appendage. The balloon is then deflated and the device can be removed from the body. With this procedure, patients are typically discharged the next day. Our senior design project focuses on the problem of delivering the contrast to the balloon during surgery preparation. The balloon is repeatedly inflated and then deflated with contrast until all of the air has been evacuated from the system. If all bubbles are not removed during preparation, the bubbles inside of the device create a potential risk of stroke if the balloon bursts and the air bubbles escape the device and then travel into the bloodstream. The contrast preparation for the current device, the EndoCATH Large Occlusion Balloon, is long and tedious when compared to existing balloon catheters. The preparation of the device is currently the largest complaint among nurses. Currently, the balloon catheter is prepared by repeatedly inflating and then deflating the balloon with contrast until all of the air bubbles are eliminated from the dual-lumen device. One lumen was used for the guidewire, and the second lumen was used for contrast. For our senior design project we proposed a dual mode tri-lumen device. Through a y-arm modification we have enabled the device to work in both a preparation mode and an inflation/deflation mode. The preparation mode provides continuous flow of the contrast to the balloon to prohibit the formation of bubbles, which significantly decreased the time required for preparation. The inflation/deflation mode allows for both lumens to be used simultaneously for inflation and deflation. This essentially reverts the device back to how it functioned as the dual-lumen device. With both modes, the dual mode tri-lumen device has significantly decreased preparation time while maintaining existing inflation/deflation times.