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The Atrial Fibrillation Ablation Center operates on the cutting edge performing innovative research. We work to develop new technologies such as virtual-reality mapping and advanced Computed Tomography (CT) imaging to simplify and improve the ablation procedure. The top picture at the right shows a CT image of an entire heart from the back so you can see the left atrium. Click below it to see the entire heart in 360 degrees.
Imaging with Flouroscopy and the CT Scan
The center picture at right shows an x-ray called fluoroscopy. Catheters are seen as dark lines. Recording electrodes are the darker spots on the catheters. When "live", the fluoroscopy can show motion like a black and white movie of the heart. Fluoroscopy provides a "flat" or 2-dimensional (2-D) picture. It shows whether catheters are aimed right or left, up or down. Fuoroscopy cannot simultaneously show if the catheters are pointing forward or backward. When there is more than one catheter, fluoroscopy cannot show which is in front and which is behind.
Fluoroscopy also only shows shades of grey with heavier substances like bones and wires appearing darker. If different body parts overlap; as in areas where the heart, lungs and ribs exist, the fluoroscopy picture can seem blurry or muddy.
The bottom right panel shows a CT image of the left atrium merged with the fluoroscopy picture to provide identification of the pulmonary veins with incredible precision. While the picture here looks flat, the computer used during the procedure can tip and turn the images to be more real-to-life. If you click on the legend below the picture you will see a movie of the left atrium by itself. The left atrium image is separated out from the whole heart image using computer technology. This makes the view simpler. The movie shows how we can tip and turn the image to see up-down, right-left and front-back directions. You can also see 2 right and 2 left pulmonary veins, and the left atrial appendage on this left atrium. During the procedure, the catheters are included in the image the doctors see while they map the abnormal heart rhythms and direct the catheters to the ablation areas.
Using three-dimensional imaging from a CT scan allows us to create an exact picture of each person’s actual left atrium instead of using standardized images of the heart and the atrium. This picture can be seen in real time on a computer screen, and the catheter used for ablation can be moved in real time to isolate the problem areas.
Recording the electrical forces
In addition to the 2-D anatomy of the live, motion fluoroscopy and 3-D CT integration image, the physician uses electrical mapping (like EKG recording), and a catheter tracking system somewhat like GPS (geographical positions systems). The positioning system can precisely track the catheter and show, in color, if the tip is pointed up or down, in or out (front or back), and right or left.
The maps define areas of the heart that are need ablation while safely identifying areas to avoid. Electrical recording can be shown in dffierent ways. We can display the electrical forces by their strength (the amount of energy or voltage that travels through the heart), or their timing (which comes first or last). We can evaluate the electrical activity in specific areas or watch it as it travels through the entire heart. The map tracks where the catheter has been and we can label all the positions where ablation energy has been delivered.
 The picture above shows a type of EKG from our electrical recording system during mapping. The left side of the picture shows normal rhythm called Sinus rhythm. Early beats (PAC = premature atrial contraction) are sometimes identified and their location can be targeted for ablation.
What's the "bottom line"?
Why are these images and maps better?
Accuracy: The maps we make have been studied for accuracy. So far they are the most accurate that we are aware of. The technologies of different pieces of equipment have been fitted together using advanced mathematics. They can be scaled to fit precisely together.
Flexibility: The images can be turned and tilted 360-degrees during the procedure to accomodate views never possible with x-rays and fluorsoscopy. Features of individual anatomy are precisely identifiable.
Exclusivity: We are the first in the country to develop and have the technology. It will most likely take 2 years before it is available at other centers.
Low Complication rates: Careful attention to detail keeps our complication rates low.
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