Preoperative cardiac risk assessment with adenosine stress dual-isotope myocardial single-photon emission computed tomography

Abstract

Background: Previous studies have demonstrated that pharmacologic stress thallium-201 (201Tl) myocardial scintigraphy is a useful tool to evaluate preoperative cardiac risk. Hypothesis: The purpose of this study was to assess the utility of adenosine stress dual-isotope [rest 201Tl/stress technetium-99m (99mTc) sestamibi] myocardial single-photon emission computed tomography (SPECT) in predicting the risk of perioperative cardiac events (unstable angina, myocardial infarction, cardiac death) in patients undergoing major noncardiac surgery. Methods: We evaluated 43 consecutive patients (20 men, 23 women, mean age 64 years, range 30-83 years) within 8 weeks prior to major noncardiac surgery requiring general anesthesia. SPECT imaging was performed with 111 MBq (3 mCi) 201Tl at rest and 925 MBq (25 mCi) 99mTc sestamibi during adenosine stress. Results: Of the 43 patients, 15 (35%) had stress-induced ischemia and 28 (65%) did not. Perioperative cardiac events occurred in 4 (27%) of the 15 patients with stress-induced ischemia 12 unstable angina, 2 nonfatal myocardial infarctions) and in none of the 28 patients without inducible ischemia (p = 0.02). Conclusion: Adenosine stress dual-isotope myocardial SPECT is useful in determining the preoperative cardiac risk of patients undergoing major noncardiac surgery.