Ventricular aneurysm is one of the complications that follow a myocardial infarction. Left ventricular (LV) plastic and reconstructive surgery, Dor procedure, is widely performed in order to improve patients' cardiac functions. However, it is anticipated that the abscission region of the ventricle might cause some complications, such as mitral valve regurgitation. Therefore, the decision of what to be done with that area might affect therapeutic consequences. In this study, the authors have developed a measurement system for surface movement and a display system to demonstrate decreased LV systolic function during surgery. This system is capable of evaluating the cardiac function using displacement data obtained from superficial motion of the specific regions. Prior to measurement, the reflective ball markers were sutured on the surface of the heart without any complications or infarctions. The point of the markers indicated the anatomically specific points, such as apex, septum, mitral valve, and papillary muscles. The location of points was sequentially measured by an optical three-dimensional location sensor. The superficial area of the left ventricle from the left thoracotomy view was divided into 12 triangular regions each composed of three markers. As the contraction of the regional area corresponds to the cardiac systolic function, the changes in each area were examined. The contraction rate of the heart was superimposed onto the video images of a natural heart, which were obtained simultaneously. An animal study was performed to compare heart functions under a normal pulsating state and during the time of a myocardial infarction. The physical data such as electrocardiogram, blood flow and pressure were simultaneously obtained and compared using this approach. With the physical data, it was confirmed that strain change in the regional area was coincident with a contraction of the actual heart. It was also found that this method is simple enough to set up in the operation theater. In the near future, this method will contribute widely to the clinical diagnoses of patients, when advanced surgery such as robot surgery and/or organ transplant become popular.
