Exercise Transcutaneous Oximetry of the Buttocks　― External Validation With Computed Tomography Angiography

• Published in: Circulation Journal Vol. 81; no. 8; pp. 1123 - 1128
• Main Authors: Audonnet, Martin, Signolet, Isabelle, Colas-Ribas, Christophe, Ammi, Myriam, Abraham, Pierre, Henni, Samir
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Circulation Society 25-07-2017
• Subjects: Aged; Blood Gas Monitoring, Transcutaneous - methods; Buttocks - blood supply; Buttocks - diagnostic imaging; Claudication; Computed tomography; Computed Tomography Angiography; Exercise; Female; Humans; Ischemia - blood; Ischemia - diagnosis; Ischemia - diagnostic imaging; Ischemia - etiology; Male; Middle Aged; Peripheral artery disease; Retrospective Studies; Computed tomography; Peripheral artery disease; Claudication
• ISSN: 1346-9843; 1347-4820
• DOI: 10.1253/circj.CJ-16-1316

Background:Exercise transcutaneous oximetry (Ex-tcPO2) is a non-invasive test for exercise-induced buttock ischemia. Prior study defined Ex-tcPO2 normal/abnormal cut-offs against arteriography but no external validation was available. The aims of this study were therefore to (1) determine the diagnostic performance of Ex-tcPO2 against CTA; (2) determine the cut-off point for detection of stenosis >75% in arteries toward the hypogastric circulation; and (3) determine the effect of chest profile classification on the diagnostic performance of Ex-tcPO2.Methods and Results:A total of 207 patients referred for Ex-tcPO2 were analyzed. DROP during Ex-tcPO2 was compared with the CTA results. Chest-tcPO2 changes were automatically classified into pre-defined profiles representing normal or abnormal responses. Using DROP <−15 mmHg as a cut-off, Ex-tcPO2 had 80.2% sensitivity, 72.3% specificity, 43.1% PPV, 93.3% NPV and 73.9% accuracy, to detect 1 stenosis >75% in arteries toward the hypogastric circulation. Optimal DROP to detect stenosis was: −15 mmHg. The overall diagnostic performance of Ex-tcPO2 was independent of chest profile classification.Conclusions:Ex-tcPO2 has satisfactory diagnostic performance to detect arterial stenoses towards the hypogastric circulation. Abnormal chest-tcPO2 profile does not impair the overall diagnostic performance of the test.