Neelima Katragunta, Joel Clements, Josh Lee, Christopher LeSar, Larry R. Sprouse
University of Tennessee, Chattanooga, TN.
OBJECTIVES: The aim of this study is to establish the significance of sharp monophasic waveform (SMW) in predicting distal arterial disease. It also attempts to clarify several inconsistencies in literature regarding the classification of arterial waveforms. The waveform that is the main focus of this study has been classified as both “sharp monophasic” and “low resistive biphasic.”
METHODS: Retrospective chart review of patients who underwent lower extremity color duplex ultrasound (CDU) exams and an angiogram within 6 weeks of the CDU over a twelve month period (Oct ’10 to Sep ’11) in Vascular Diagnostic Center (VDS) was done to identify SMWs in the lower extremity and then correlate with angiographic findings. The data were then used to calculate the positive predictive value of the SMW in predicting a hemodynamically significant distal lesion.
RESULTS: There were 46 limbs (43 patients) that qualified for inclusion in the study. Of these, two cases were eliminated due to unclear angiographic findings. Of the 44 remaining limbs that qualified, there were 36 (81.8%) cases in which the presence of SMW was associated with distal lesions and 8 (18.2%) cases in which it was not. This gives the presence of SMW a positive predictive value of 81.8% in predicting disease distal to its location.
CONCLUSIONS: SMW is helpful in diagnosing hemodynamically significant distal arterial obstruction. It is a waveform that is distinctly different from biphasic or poor monophasic waveforms both in morphology and diagnostic significance. Further studies are needed to prospectively examine these findings that could improve the diagnostic accuracy of arterial ultrasound.
AUTHOR DISCLOSURES: J. Clements, Nothing to disclose; N. Katragunta, Nothing to disclose; J. Lee, Nothing to disclose; C. LeSar, Nothing to disclose; L. R. Sprouse, Nothing to disclose.
Posted April 2012