Viability by MRI or PET Would Not Have Changed the Results of the STICH Trial

The assessment of myocardial viability in the Surgical Treatment for Ischemic Heart Failure (STICH) trial of patients with ischemic cardiomyopathy did not identify patients who had a survival benefit from coronary artery bypass grafting compared to medical therapy alone. Viability testing was performed with either single-photon emission computed tomography (SPECT), dobutamine echocardiography (DE), or both. The question has been raised as to whether the addition of magnetic resonance imaging (MRI) or positron emission tomography (PET) imaging may have changed these results. Comparisons of the important similarities and differences of these viability imaging techniques, as well as of the design and limitations of the STICH viability substudy, suggest that the addition of MRI or PET imaging for viability assessment would not change the study results. The results of the STICH viability substudy are probably not a reflection of the modality of viability testing used, but rather an indication of the substantive effect of optimal medical therapy.