Association between abnormal myocardial scintigraphy findings and long-term outcomes for elderly patients 85 years or older: a retrospective cohort study

Background: Normal findings of cardiac scintigraphy predict good outcomes. However, a paucity of the data exists for elderly patients 85 years or older. In the present study, we aimed to demonstrate the association between the abnormal findings of cardiac scintigraphy and the risk of all cause death in patients 85 years or older. Methods: We enrolled 143 consecutive patients 85 years or older with known or suspected coronary artery disease who underwent stress scintigraphy under adenosine or an exercise test and a ⁹⁹mTechnetium (Tc)-labeled tracer or thallium 201 (²⁰¹Tl and ¹²³I-β-methyl iodophenyl pentadecanoic acid (¹²³I-BMIPP), or ¹²³I-BMIPP single tracer scintigraphy. Ischemia was defined by an induced perfusion abnormality according to a provocation test with recovery at rest or decreased uptake of ¹³³I-BMIPP despite normal perfusion at rest. Infarction was defined by perfusion abnormalities assessed by images at rest on ²⁰¹Tl or ⁹⁹mTc-labeled tracer. We defined these findings as abnormal when at least one of these aforementioned characteristics was observed. Results: Patients in the abnormal findings group (N = 62) were more likely to have undergone prior coronary angiography and to have decreased ejection fraction than those in the normal findings group (N = 81). The median follow-up duration was 797 days (interquartile range, 635–1045 days), with follow-up rates of 90% at 1 year and 73% at 2 years. The 2-year mortality rate were significantly higher in the abnormal findings group than in the normal findings group (26.8% vs. 10.9%; p = 0.01). The risk of abnormal findings relative to normal findings remained significant for the mortality (adjusted hazard ratio, 5.99; 95% CI, 1.37–42.8; P = 0.015). Conclusion: Abnormal myocardial scintigraphy findings were associated with the increased risk for mortality, even for patients 85 years or older