Quantitative regional curvature analysis: validation in animals of a method for assessing regional ventricular...

Recent studies show the impact of left ventricular shape and remodelling on patient prognosis. This mandates the development of quantitative methods for measuring shape. Quantitative regional curvature analysis (QRCA) was developed to quantitate shape on a regional basis so that measurements would not be constrained to assessment of only global shape and would, therefore be applicable to ischemic heart disease. To validate QRCA, eleven dogs were instrumented with coronary occluders and radiopaque markers on the epicardium and endocardium to provide fiducial points for calculation of shape, motion and thickening. These parameters were measured in the anterior and inferior walls, at rest, during left anterior descending occlusion and finally during circumflex occlusion. QRCA showed increased curvature (increased globularity) in each wall when thickening and motion deteriorated during occlusion. The most marked shape changes occurred in the inferior wall whereas the most marked deterioration of function was detected by wall thickening measurements of the anterior wall. Thus, QRCA detects regional ventricular shape disorders coincident with regional dysfunction induced by ischemia. These changes show regional heterogeneity and demonstrate the potential importance of this measurement as opposed to simple, global measures of shape. QRCA is, therefore, suitable for monitoring acute changes of shape that occur during acute ischemia.