Abstract
Background The incidence of missed diagnoses of acute cardiac ischemia in the emergency department could be reduced by a new imaging modality. In the present study, the clinical significance of 99mTc-pyrophosphate (PYP), 123I-β-methyl-p-iodephenyl-pentadecanoic acid (BMIPP), 201TlCl scintigraphy (imaging) and T2-weighted inversion - recovery magnetic resonance imaging (MRI) for the detection of culprit lesion in patients with acute coronary syndromes (ACS) was compared. Methods and Results The study group comprised 18 patients with ACS: 12 patients with acute myocardial infarction (AMI) (11 males; mean age, 63±11 years) and 6 patients with unstable angina (UA) (3 males, mean age, 67±5 years). Of the 12 patients with AMI, 10 underwent 201TlCl and PYP single photon emission computed tomography (SPECT) studies as a dual-energy acquisition (201TlCl/PYP) and 8 underwent 201TlCl SPECT within 1 week of the BMIPP study. All 18 patients underwent BMIPP SPECT and MRI. The MRI pulse sequence was black blood turbo short-inversion-time inversion recovery (STIR) (breath-hold T2-weighted studies). The T2-weighted inversion-recovery MRI showed higher sensitivity and negative predictive value than PYP and 201TlCl, and higher specificity and positive predictive value than BMIPP and 201TlCl. The area under the receiver-operating characteristic curve for PYP, BMIPP, 201TlCl and MRI was 0.787, 0.725, 0.731 and 0.878, respectively. The difference between the areas of MRI and BMIPP was significant (p<0.05). Conclusion Accurate detection of culprit lesion is improved by using MRI rather than BMIPP, particularly for patients with ACS. (Circ J 2004; 68: 1023 - 1029)
