This case report describes an unusual form of cardiomyopathy in a child with abnormalities in both ventricular relaxation and compliance. The diastolic abnormalities are well-defined using Doppler inflow velocities and Doppler tissue imaging, and the Doppler findings are correlated with intracardiac pressure measurements. This case illustrates the use of noninvasive Doppler techniques in identifying diastolic dysfunction, and it sheds additional light on the interplay of relaxation, compliance, and heart rate in creating the variable inflow Doppler patterns encountered clinically.