Using Abnormal Respiratory Motion on Myocardial Perfusion Scintigraphy as an Opportunity to Screen for Obstructive Sleep Apnea

A pilot study was performed to determine whether the raw data from routinely obtained upright and supine myocardial perfusion scan (MPS) imaging could be used as an opportunity to screen for obstructive sleep apnea (OSA). We hypothesized that abnormal respiratory motion seen only on supine imaging (not upright imaging) corresponds with OSA. MPS supine-only respiratory motion was compared with known OSA diagnoses and with risk factors known to be associated with OSA. Methods: We reviewed 154 consecutive MPS studies from patients at our institution, including both exercise and chemical stress testing. All examinations were obtained because there was clinical suspicion of myocardial ischemia. We used the MPS panogram to assess for respiratory motion on supine stress or upright rest or stress imaging. We obtained the age, sex, body mass index, hypertensive history, and continuous positive airway pressure or OSA diagnosis history. Results: We compared the patients who had supine, stress-only respiratory motion with the remaining patients, assessing their OSA risk factors and known OSA diagnoses. In total, 65 patients (42.2%) had 3 or more OSA risk factors and 26 patients (16.9%) had a known OSA diagnosis. A similar percentage of patients with abnormal supine-only respiratory motion and patients with 3 or more OSA risk factors had a known OSA diagnosis, 9 (16.7%) and 14 (21.5%), respectively. Conclusion: We found a similar prevalence of known OSA diagnoses in patients with abnormal supine-only respiratory motion on MPS studies and patients with 3 or more OSA risk factors. The pilot study suggests that assessment of motion on MPS studies may provide an opportunity to also screen for OSA.