[Emission-computed tomography of the myocardium with the 7-pinhole collimator]

89 patients (78 with coronary artery disease, 11 normals) were studied comparatively with T1-201 planar myocardial scintigraphy and 7-pinhole emission tomography with a mobile gamma-camera. In 46 patients stress studies were performed, the other studies were performed as resting protocols. In 13 patients a correlation of scintigraphically determined infarct size calculated from the T1-201 tomograms with CK and CK-MB values (maximum values) in the acute infarction period was performed. 17 patients having undergone intracoronary streptolysis were studied to investigate the effect of this intervention. In patients without previous myocardial infarction (n = 35) sensitivity of 7-pinhole tomography was significantly superior over planar reading of images (83% for qualitative evaluation, 91% for quantitative analysis). In patients with previous myocardial infarction (n = 26) comparative sensitivities were not significantly different, although slightly higher, nevertheless the fraction of questionable findings was reduced from 9 to 4%, furthermore in 31% an additional information concerning size or localization could be obtained from the tomograms. Predictive diagnostic accuracy was highest for quantitative 7-pinhole tomography (91%) but not significantly different from qualitative tomography but higher than for planar imaging. Specificities of all methods were comparable. In patients during the acute phase of myocardial infarction a significant correlation (r = 0.76 for CK, r = 0.78 for CK-MB, p less than 0.01) was obtained with enzymatic markers of infarct size. In the group after intracoronary streptolysis 7-pinhole tomography was able to demonstrate a quantitative reduction of thallium infarct size in patients after successful lysis (23.5% vs 48.7%, p less than 0.01) although absolute quantitation is not possible with thallium-201 due to inherent biological limitations. Emission tomography using 7-pinhole collimation leads to an improvement of diagnostic accuracy in all patients with reversible ischemia and helps for better delineation of size and localization of infarct areas and could help in the assessment of interventional effects, as after intracoronary streptolysis.