Myocardial perfusion echocardiography and coronary microvascular dysfunction

Figure 4 Parametric quantification of myocardial perfusion. Critical stenosis of the circumflex artery is present at coronary angiography (right panels). Parametric images of peak dipyridamole stress echo reported in panels A through D represent, respectively, the plateau value A of the contrast replenishment curve, the slope β of the replenishment curve, the A ×β value, and the goodness of fitting. The A ×β value parametric imaging is also displayed superimposed onto the apical four-chamber view in the top left panel. Replenishment time-course curves (sampling and interpolation) relative to the septum (white curves) and the apico-lateral wall (red curves) are reported in the graph at the bottom. Flow is reduced in the territory perfused by circumflex artery.