Myocardial Perfusion Imaging Before and After Cardiac Revascularization

Abstract Coronary artery disease (CAD) remains the leading cause of morbidity and mortality worldwide. While the burden of the disease remains high, the rates of death attributable to CAD have declined by almost a third between 1998 and 2008. In patients with stable ischemic heart disease (SIHD), data supporting survival benefit from coronary artery bypass graft surgery (CABG) or percutaneous coronary intervention (PCI) versus no revascularization are outdated with the recent advancement in medical therapy. Over the years, myocardial perfusion imaging (MPI) has played a significant role in detecting ischemic burden, risk stratifying patients and guiding physicians to the best treatment strategy. Contrary to data from other trials, the role of stress MPI has been downplayed in more contemporary randomized clinical trial that failed to show that ischemic burden identifies the ideal candidate for revascularization or carries incremental prognostic value. Hence, there is an equipoise on the role of MPI in the management of patients prior to revascularization. The role of stress MPI post-revascularization has also been evaluated in multiple studies, mostly done in the last decade or prior. The guidelines advocate against routine stress MPI in asymptomatic patients (unless 5 years or more post-CABG), but allows it in the presence or recurrence of symptoms. The current chapter will review the data on survival benefit from revascularization, complementary role of stress MPI in selecting the appropriate candidate for revascularization, prognostic value of ischemic versus atherosclerotic burden, role of MPI post revascularization, updated guidelines and proposed algorithms to guide the treating physicians.