Scintigraphic Myocardial Imaging with ^99mTc-Labelled Pyrophosphate of Experimentally Produced Cardiomyopathy in Dogs

Scintigraphic examination of the myocardium using ^99mTc-labelled pyrophosphate was carried out in 10 dogs with experimentally produced cardiomyopathy. This was brought about by intravenous administration of high doses of adrenalin and theophylline. The scan was positive in 8 out of 10 dogs. "Hot" foci were very extensive. The degree of accumulation was however low (2+). Histological examination of the myocardium using the light microscope showed only scarcely distinguishable damage to the tissue without the presence of necrosis. ECG examinations were normal in all cases. By means of ^99mTc-labelled pyrophosphate even very small myocardial disorders can thus be detected. This fact may be of clinical importance for an early diagnosis of heart lesions.

Es wurde eine szintigraphische Myokard-Untersuchung mittels ^99mTc-markierten Pyrophosphats bei 10 Hunden mit einer experimentell verursachten Kardiomyopathie durchgeführt. Diese war durch intravenöse Verabreichung hoher Adrenalin- und Theophyllindosen herbeigeführt worden. Der Myokard-Scan war positiv bei 8 von 10 Hunden. „Heiße” Herde waren sehr ausgedehnt, die Speicherung war jedoch niedrig (2+). Die histologische Myokard-Untersuchung mittels des Lichtmikroskops ergab einen kaum feststellbaren Gewebsschaden ohne Vorhandensein einer Nekrose. Die EKG-Untersuchungen waren in allen Fällen normal. Mittels ^99mTc-markierten Pyrophosphats können daher auch sehr geringfügige Myokardstörungen entdeckt werden. Diese Tatsache kann für eine Frühdiagnose der Herzschäden von klinischer Bedeutung sein.

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