**4. Implementation**

the format specified in the AHA committee report and stored as an XML file. Figure 16 shows the relationship between our system and CAG. The top screen in Figure 16 (a) presents an example of recording stenoses using our system; the middle screen of Figure 16 (a) shows the CAG dataset it produces. Any other system that supports this format can use

The user can also edit the exported CAG table. When this happens, our system automatical‐ ly updates the corresponding stenosis on the coronary diagram including the information

When a stenosis is straddling two or more segments, it is considered to belong to two or more segments. The stenosis drawn on LAD7 and LAD8 amid the strangulation shown in

(a) (b)

**Figure 16.** Example of the automatic relationship between the coronary diagram and the CAG table. (a) The system automatically generates a CAG table from a graphical coronary schema by checking the existence of a stenosis in each segment of the coronary arteries, and stores the results in XML format. (b) The system can automatically update the

stenoses on the coronary schema from the corresponding CAG table.

the data file as shown in the bottom screen of Figure 16 (a).

on the severity and character of the stenosis (Figure 16 (b)).

Figure 17 is an example.

376 Artery Bypass

We designed our system as a platform-independent JavaTM program using the Java2DTM graphics application programming interface. This section describes the implementation de‐ tails of the current prototype.

#### **4.1. On-screen displays**

The system displays coronary arteries as two parallel lines and handles the branches ap‐ propriately (Figure 18 (a)). A vessel is a polyline composed of small line segments. The system first draws a wide red line and then a narrow white line inside (Figure 18 (b1), (b2)). The width of these lines decreases toward the non-connected end of a vessel to represent the taper (Figure 18 (c1), (c2)).

A stenosis is displayed in a similar manner. The system first draws a wide black line inside the vessel and then a narrow white line inside that. A stent is rendered by drawing a hatch‐ ing pattern after setting a stencil inside the stent area.

**4.3. Generation of the CAG table**

in XML format (Figure 16 (a), middle and bottom).

**5. Case report using our system**

circumflex branch of the left coronary artery.'

**Figure 20.** Case 1 of the report [14] using our system.

papers.

The CAG table stores the following information for each segment of a coronary artery: the presence or absence of a stenosis, the severity of the stenosis, and the type of stenosis (Fig‐ ure 16 (a), bottom). The system automatically generates a CAG table from a graphical coro‐ nary schema by checking for the existence of a stenosis in each segment. It stores the result

Generating Graphical Reports on Cardiac Catheterization

http://dx.doi.org/10.5772/54235

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When the user edits the CAG table, the system first finds the corresponding stenosis in the XML file (Figure 16 (b), top and middle). It then obtains the information for that stenosis and changes it on the coronary schema. In this way, the system automatically updates the sten‐ oses on the coronary schema from the corresponding CAG table (Figure 16 (b), bottom).

We illustrate the effectiveness of our system, utilizing two cases of coronary artery bypass surgery as examples. These examples were only described (not illustrated) in the original

`A man, 45 years of age, had suffered attacks of angina pectoris during many years. He had had infarction of the myocardi‐ um. During the operation it was noted that the left coronary artery and the initial portions of its main branches were calci‐ fied. We also noted density of the right coronary artery. Anastomosis was applied between the inner thoracic artery and the

The first example is Case 1 of [14]. The paper describes it as follows:

**Figure 18.** Vessel representation. The system displays coronary arteries as two parallel lines and handles the branches appropriately (a). The system first draws a wide red line (b1), and then a narrow white line inside (b2). The width of these lines decreases toward the non-connected end of a vessel to represent the taper (c1, c2).

#### **4.2. Geometry editing**

The pulling interface deforms the curve while maintaining its local details (Figure 5 (c)) [13]. The system first generates triangles by connecting sets of three neighboring points on a polyline. As the user pulls a point along the curve, the system determines the location of free vertices so as to minimize the distortion of the triangles. We also used the peeling interface introduced in [13] to adjust the size of the region to be deformed, so that a larger area is de‐ formed as the user pulls more. As the user pulls the curve further away, the influence region grows (Figure 19, left to right).

**Figure 19.** We use the pulling and peeling interface introduced in [13]. As the user pulls the curve further away, the influence region grows (left to right).
