Echocardiographic evaluation of partial anomalous pulmonary venous drainage.

Objectives: This study was undertaken to determine the accuracy of routine echocardiography in the detection of partial anomalous pulmonary venous drainage.
Background: Although there are occasional case reports of the echocardiographic appearance of partial anomalous pulmonary venous drainage, no large series have addressed the accuracy of this technique in a large cohort of patients.
Methods: Between January 1983 and December 1993, 50 patients with partial anomalous pulmonary venous drainage (with or without an associated atrial septal defect as the only other significant intracardiac defect) were identified from the data base at the Hospital For Sick Children, Toronto. Routine echocardiographic reports were reviewed, and the results were compared with surgical or catheterization findings. Risk factors related to diagnostic errors were sought using a Fisher exact test, chi-square analysis, t test and Kruskal-Wallis analysis of variance.
Results: Confirmation of the diagnosis was available in 45 patients whose data were subsequently used for risk factor analysis. The median age at echocardiography was 4.1 years (range 1 month to 18 years). Right-sided drainage was present in 43 patients (86%), with left-sided drainage in 7 (14%). Thirteen patients had an intact atrial septum, 7 a patent foramen ovale and 30 a secundum atrial septal defect. Right ventricular dilation was observed in 46 patients. Two had normal dimensions (two not assessed). The diagnosis was missed by echocardiography in 15 (33%) of the 45 patients with a confirmed diagnosis. Year of study and use of color flow mapping were the only significant variables related to detection rate (7% missed diagnosis with vs. 62% without the use of color flow, p < 0.0005). The median year of missed diagnosis was 1985 versus 1990 (p < 0.002). Transesophageal echocardiography accurately defined the site of drainage in all three patients in whom it was utilized.
Conclusions: Two-dimensional echocardiography in conjunction with color flow mapping is a valuable tool for the diagnosis of partial anomalous pulmonary venous drainage.