Background: Myocardial perfusion scintigraphy (MPS) is a well-established diagnostic tool. The sensitivity and specificity of single photon emission computed tomography (SPECT) MPS to detect significant coronary lesion were 86% and 74%, respectively. The aim of this study was to examine the role of serum copeptin in evaluation of MPS.
Methods: Sixty-two consecutive patients underwent both SPECT MPS using 99mTc-sestamibi and transthoracic echocardiography were enrolled prospectively. Age, gender, height, weight, presence of cardiovascular risk factors were recorded. Exercise treadmill test (ETT) with modified Bruce protocol was used to induce coronary ischemia during MPS. While performing MPS, blood samples for serum copeptin level were drawn three times at pre-exercise, at the peak of ETT, and 6 h after ETT, respectively. The patients were enrolled into three groups according to MPS results (normal, equivocal and ischemia).
Results: The study included 62 patients (23 with normal, 20 with equivocal, 19 with ischemia on MPS). Pre-, peak-, and post-exercise B-type natriuretic peptide and troponin I values were similar across the groups (p > 0.05 for all comparisons). Serum copeptin values for pre- and peak-exercise were similar among all groups (p = 0.883 and p = 0.089). Post-exercise copeptin values of the normal and equivocal groups were similar (p = 0.661, z = –0.438) while that of the ischemia group was significantly higher than both the normal (p < 0.001) and equivocal group (p < 0.001).
Conclusions: Serum copeptin was found to be increasing significantly in case of ischemia on MPS. It may be used in differentiation of equivocal results from false positive results.
