Spectrum of M-mode echocardiographic findings in total anomalous pulmonary venous return

The results of our study, which is the largest reported M-mode echocardiographic study in pediatric patients with TAPVR, demonstrate that the M-mode echocardiographic findings mirror the varied clinical spectrum of this disease. In the older patients who are acyanotic and have a left-to-right shunt, the echocardiographic findings are those of a right ventricular volume overload. In the newborn group, particularly in those with pulmonary venous obstruction with TAPVR below the diaphragm, the echocardiographic signs are those of pulmonary hypertension with a dilated right heart, and one may note a small-appearing left atrium. TAPVR will remain a challenge in the newborn. The M-mode echocardiographic findings are not specific in this particular lesion. Perhaps newer techniques of echocardiographic imaging with the use of two-dimensional echocardiography will improve our diagnostic capabilities.