Doppler Characteristics of Coronary Blood Flow in Infantile Hypertrophic Cardiomyopathy with Cardiac Tamponade

The co-existence of severe hypertrophic cardiomyopathy and massive pericardial effusion is a rare combination that may lead to a significant decrease in diastolic cardiac filling with marked hemodynamic compromise. We present a unique case where both conditions co-existed in an infant leading to marked diastolic cardiac dysfunction. It was possible to image the prominent epicardial coronary arteries and assess the coronary blood flow before and after pericardiocentesis using transthoracic two-dimensional Doppler echocardiography. With large pericardial effusion, there was a significant reduction in coronary blood flow during systole, which increased after pericardiocentesis. The exact mechanism for such phenomenon is only speculative.