Is resting echocardiography sensitive for detecting CAD? Why or why not?

No, for three reasons:
1. Many coronary plaques do not diminish resting myocardial blood flow and thus do not produce wall motion abnormalities at rest.
2. Because the movement of one myocardial segment is influenced by adjacent segments as a result of the tethering effect, abnormal thickening may be masked.
3. Abnormal myocardial thickening may be secondary to a nonischemic etiology, such as cardiomyopathy or valvular disease.