MM Abu-Yousef, ME Kakish and M Mufid
1 Department of Radiology, University of Iowa College of Medicine, Iowa City 52242, USA.
OBJECTIVE: The purpose of this study was to determine if pulsatile flow in lower limbs as seen on venous Doppler waveforms correlates with increased right atrium pressure.
MATERIALS AND METHODS: Of 429 patients who, over a 14-month period, underwent venous Doppler imaging of the lower limb to exclude deep venous thrombosis, 343 records were available for review at the time of the study. Of these, 74 had right atrium pressure measurements available for correlation. Seventeen patients were excluded because of thrombosis in the common femoral vein. Six other patients were also excluded because the time difference between the Doppler and the correlative studies was more than 4 weeks. The remaining 51 patients constituted the study subjects. In 18 of these, the right atrium pressure was measured within 1 week, 31 within 2 weeks, 42 within 3 weeks, and 51 within 4 weeks. In the study, we evaluated the three major veins of the lower limb (the common femoral, superficial femoral, and popliteal) by venous Doppler imaging. Data from only the common femoral vein were included in our analysis because this vessel was the least involved with thrombosis. The findings were correlated with the presence or absence of right-sided heart failure as determined by right atrium pressure measurement. A Doppler waveform was considered pulsatile when it had a cyclic retrograde component. A right atrium pressure of more than 8 mm Hg was considered elevated.
RESULTS: Of 51 patients, 17 (33%) had pulsatile lower limb venous Doppler flow waveforms and 33 (65%) had elevated right atrium pressure. We found a statistically significant correlation between the presence of these abnormal waveforms and elevated right atrium pressure. The sensitivity of lower limb venous Doppler imaging for detecting right-sided heart failure as determined by right atrium pressure measurement was 46%, specificity was 94%, positive predictive value was 94%, negative predictive value was 50%, and accuracy was 65%.
CONCLUSION: Pulsatile lower limb venous Doppler waveform correlates well with right-sided heart failure, as indicated by a right atrium pressure measurement of more than 8 mm Hg. However, because of its low sensitivity, lower limb venous Doppler imaging cannot be used to screen for right-sided heart failure.