Prognostic value of lung sestamibi uptake in myocardial perfusion imaging of patients with known or suspected coronary artery disease.

Abstract

We sought to determine whether lung uptake of technetium-99m (99mTc)-based myocardial perfusion tracers predicts cardiac events. Increased lung uptake of thallium-201 during myocardial perfusion scintigraphy can predict important clinical outcomes. It is unclear whether lung uptake of 99mTc-based myocardial perfusion tracers can be used in a similar way. Stress lung-to-heart ratio (sLHR) was determined in 718 patients undergoing 99mTc-sestamibi single-photon emission computed tomographic stress imaging. The primary outcome was acute myocardial infarction or death. During a mean follow-up of 5.6 years, a primary end point occurred in 114 patients (16%). The sLHR was significantly greater in those with an adverse outcome (p < 0.00001). The likelihood of an adverse outcome increased by a factor of 1.5 (95% confidence interval 1.2 to 1.7) for each standard deviation increase in sLHR after adjustment for all other variables. The sLHR provided a small but significant improvement in risk stratification when added to clinical, stress test, perfusion, and left ventricular volume information (global chi-square 168.6 vs. 150.7, p < 0.00001). Stress LHR is an adjunctive prognostic measure in patients with known or suspected coronary artery disease.