The prognostic significance of the doughnut pattern of technetium-99m pyrophosphate myocardial uptake was evaluated in 140 patients with acute anterior infarction. There were significantly higher early complications, greater mortality and more severe hemodynamic abnormalities in the doughnut pattern group than in the non-doughnut pattern group. The former had a more depressed left ventricular ejection fraction and larger thallium-201 defect size (27.6 +/- 10.4 versus 40.0 +/- 13.5%, p less than 0.001 and 9.9 +/- 3.6 versus 5.6 +/- 3.3, p less than 0.001, respectively). There was, however, considerable overlap of the ranges of these variables for both groups. The patency rate of the infarct vessel during the acute phase of infarct in each group was similar (54.8 versus 45.2%). It is concluded that the prognostic value of the doughnut pattern may be limited to some extent by this overlapping and the presence of this pattern does not appear to correlate with the lack of residual blood flow to the infarcted area.