Detection of occult pericardial hemorrhage early after open-heart surgery using technetium-99m red blood cell radionuclide ventriculography.

Pericardial or mediastinal hemorrhage requiring reoperation occurs in 2% to 5% of patients, usually early (0 to 48 hours), after open-heart surgery. This hemorrhage may be occult, and resulting cardiac tamponade may easily be misinterpreted as ventricular dysfunction, common early postoperatively. In such cases, appropriate and timely intervention may not occur. Of 50 patients evaluated by technetium-99m red blood cell gated equilibrium radionuclide ventriculography (RNV) because of early postoperative cardiogenic shock of uncertain etiology, 17 had unique scintigraphic images suggestive of intrathoracic hemorrhage. Of these 17, 5 had a generalized "halo" of abnormal radioactivity surrounding small hyperdynamic right and left ventricles, 11 had localized regions of intense blood pool activity outside the cardiac chambers (two with compression of single chambers), and one demonstrated marked radionuclide activity in the right hemithorax (2000 ml of blood at reoperation). Twelve patients had exploratory reoperation for control of hemorrhage as a direct result of the scintigraphic findings, three were successfully treated with fresh frozen plasma and platelet infusions along with medical interventions to optimize cardiac performance, and two patients died in cardiogenic shock (presumed tamponade) without reoperation. In the 12 reoperated patients, all were confirmed to have active pericardial bleeding. Scintigraphic localization of abnormal blood pools within the pericardium corresponded to the sites at which active bleeding was witnessed at reoperation. The abnormal bleeding was etiologically related to the tamponade state, with marked improvement in hemodynamics after reoperation. Nine additional patients were reoperated for presumed tamponade after RNV revealed an exaggerated halo of photon deficiency surrounding the cardiac chambers.(ABSTRACT TRUNCATED AT 250 WORDS)