Hypertrophic cardiomyopathy and cardiac amyloidosis result in thickening of the left ventricle, as visualized by 2-dimensional echocardiography. Hemodynamically, hypertrophic cardiomyopathy can be typified by a left ventricular outflow tract gradient and systolic anterior motion of the mitral apparatus, findings rarely seen in cardiac amyloidosis. This case series reports 4 patients with cardiac light-chain amyloidosis and left ventricular outflow tract obstruction at rest, suggesting that there may be echocardiographic overlap between these 2 disparate disease processes. In a series of consecutive patients with cardiac light-chain amyloidosis over a 2-year period, the prevalence of these echocardiographic findings was approximately 4%. In conclusion, awareness of this overlap in echocardiographic presentation may permit more accurate diagnosis, particularly at early stages of amyloid disease, when more treatment options exist.