Introduction: In patients with suspected ischemia, myocardial perfusion imaging (MPI) with PET has been shown to provide greater diagnostic accuracy and improved risk stratification over SPECT MPI. As such, PET MPI could lead to improved post-test management, which could impact subsequent patient health status (symptoms, function and quality of life). We compared the health status outcomes for patients undergoing stress MPI for suspected ischemia using PET vs SPECT.
Methods: At a single health system, patients with CAD and suspected ischemia were randomized to PET or SPECT MPI from 6/2009-9/2013. Post-test management was at the discretion of the referring physician. The Seattle Angina Questionnaire (SAQ) was prospectively collected at baseline, 1, 3, 6 and 12 months, and the Angina Frequency (AF), Physical Limitations (PL), and Quality of Life (QL) domain scores were compared between MPI modalities using linear repeated measures model.
Results: Among 322 patients with CAD randomized to PET vs. SPECT (n=161 in each group, mean age 66.3 ± 9.7 years, 64.9% men, 27.6% with diabetes, 14.0% with ischemia (≥10% myocardium)), all SAQ domains increased significantly from baseline with the largest changes observed within the first 1 month after MPI (Figure). However, the changes in SAQ domain scores were similar between the imaging modalities (SAQ AF: p=0.70, SAQ PL: p=0.07, SAQ QL: p=0.20).
Conclusions: In symptomatic patients with CAD undergoing stress MPI, health status improved significantly over a year of follow-up. Although PET MPI more accurately details the ischemia, use of this imaging modality did not translate into improved health status over time.