ASSESSMENT OF ACUTE MYOCARDIAL NECROSIS AFTER CARDIOPULMONARY-RESUSCITATION AND CARDIOVERSION BY MEANS OF COMBINED TL-201 TC-99M PYROPHOSPHATE TOMOGRAPHY

Diagnosis of acute myocardial necrosis by means of conventional electr ocardiographic criteria or the release of cardiac enzymes is often dif ficult or even impossible in patients with out-of-hospital cardiac arr est due to ventricular fibrillation with subsequent cardiopulmonary re suscitation including several DC counter-shocks. Simultaneous thallium -201/technetium-99m pyrophosphate (PYP) tomography was prospectively a pplied to 57 patients without typical clinical or electrocardiographic signs of acute myocardial infarction within 48 h after successful res uscitation from out-of-hospital cardiac arrest. Scintigraphic evidence of acute necrosis was present in 23/57 patients (40%). Increased Tc-9 9m-PYP uptake in the pericardial tissue was found in 24 patients (42%) . Maximal creatine kinase (CK) concentration was increased in 50/57 pa tients (88%). CK-MB activity averaged 68+/-52 U/l in patients with pos itive and 17+/-13 U/l in patients with negative tomograms (P<0.0005), demonstrating the validity of Tl-201/Tc-99m-PYP tomography. It may be concluded that simultaneous Tl-201/(TC)-T-99m-PYP tomography is a valu able tool for evaluation of myocardial necrosis after cardiopulmonary resuscitation including DC countershock. Acute myocardial necrosis, as indicated by scintigraphy, represents a potential trigger for the occ urrence of ventricular fibrillation. Therefore, Tl-201/(TC)-T-99m-PYP tomography can be recommended in order to guide further diagnostic and therapeutic interventions in patients after cardiopulmonary resuscita tion in whom the underlying cause of the occurrence of ventricular fib rillation is obscure.