Lower extremity arterial evaluation: are segmental arterial blood pressures worthwhile?

Area of Science:

• Vascular Medicine
• Diagnostic Imaging
• Medical Technology

Background:

• Lower extremity arterial disease severity is assessed using physiologic observations, including blood flow waveform analysis and pressure measurements.
• Segmental blood pressures (SEGPs) at the thigh, calf, and ankle are common but understudied diagnostic tools.

Purpose of the Study:

• To quantify the accuracy improvements of adding ankle-brachial index (ABI) or SEGP data to Doppler ultrasound velocity waveforms compared to arteriography.
• To evaluate the diagnostic utility of SEGPs in conjunction with waveform analysis for lower extremity arterial disease.

Main Methods:

• Continuous-wave Doppler velocity waveforms were recorded at common femoral, popliteal, and tibial arteries.
• Systolic SEGPs were obtained using thigh, calf, and ankle cuffs.
• Waveforms, waveforms plus ABI, and waveforms plus SEGP data were analyzed by blinded technologists and physicians across four institutions.

Main Results:

• Doppler waveform analysis alone showed varying accuracy (64-83%) for different arterial segments.
• Adding ABI significantly improved accuracy (p < 0.01) across all segments (70-88%).
• Incorporating SEGP data instead of ABI yielded inferior accuracy compared to ABI alone.

Conclusions:

• Ankle-brachial index (ABI) significantly enhances the accuracy of Doppler waveform analysis for diagnosing lower extremity arterial disease.
• Segmental pressure measurements above the ankle do not improve diagnostic accuracy when added to waveform and ABI data.
• Pressure measurements above the ankle may not be cost-effective or clinically useful for this diagnostic purpose.