Clinical application of ⁹⁹Tc^m-tetrofosmin in diagnosis patients with coronary heart disease

Objective: To evaluate the diagnostic value of ⁹⁹Tc^m-tetrofosmin(TF) stress-rest MPI in detecting CHD. Methods: Eighty patients with suspected CHD who had stress-rest MPI from October 2009 to April 2011 were retrospectively analyzed.Forty underwent ⁹⁹Tc^m-TF (group A) and 40 received ⁹⁹Tc^m-MIBI (group B) stress-rest MPI. Heart/lung (H/L) ratios of these two groups were compared.CAG was performed on group A patients 3 months before and after MPI. Stenosis of more than 50% in CAG was used as a standard to evaluate the diagnostic efficiency of ⁹⁹Tc^m-TF MPI. Paired t test and χ² test were used to compare the data. Results: H/L ratios of rest and stress from ⁹⁹Tc^m-TF images were 6.73 ± 1.21 and 6.94 ± 1.69, while those from ⁹⁹Tc^m-MIBI images were 6.58 ± 1.94 and 6.64 ± 1.81, respectively. There was no difference between ⁹⁹Tc^m-TF and ⁹⁹Tc^m-MIBI imaging in both rest and stress (t=0.41, 0.78, both P>0.05). There was no difference between H/L ratios from stress and rest ⁹⁹Tc^m-TF imaging (t=0.69, P >0.05). Twenty-four patients who underwent ⁹⁹Tc^m-TF imaging had abnormal perfusion (60.0%, 24/40), including 20 LAD, 11 LCX and 14 RCA. Twenty-three among these 40 patients had abnormal CAG results (57.5%, 23/40), including 19 LAD, 12 LCX, and 11 RCA. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ⁹⁹Tc^m-TF stress-rest MPI were 87.0% (20/23), 76.5% (13/17), 82.5% (33/40), 83.3% (20/24) and 81.2% (13/16), respectively. The sensitivities of ⁹⁹Tc^m-TF stress-rest MPI for detection of LAD, LCX and RCA were 89.5% (17/19), 83.3% (10/12) and 90.9% (10/11), respectively,and positive predictive values were 85.0% (17/20), 90.9% (10/11) and 71.4% (10/14), respectively. There was no significant difference for sensitivity and positive predictive value of ⁹⁹Tc^m-TF MPI among different vessels (χ²=0.377 and 1.789, both P>0.05). Conclusions: ⁹⁹Tc^m-TF MPI has comparative imaging quality to ⁹⁹Tc^m-MIBI MPI. ⁹⁹Tc^m-TF stress-rest MPI is a reliable method for detecting CHD. (authors)