Comparison of duplex ultrasound and hemodynamic assessment with computed tomography angiography in patients with arterial thoracic outlet syndrome

Abstract

Thoracic outlet syndrome (TOS) presents with a variety of neurovascular symptoms, and its diagnosis cannot be established purely on the basis of clinical assessments. Computed tomography angiography (CTA) is currently the most useful investigative modality for patients with suspected vascular TOS. However, CTA facilities are limited, and CTA itself is an expensive and a resource-intensive technique associated with risks such as radiation exposure and contrast toxicity. Therefore, a screening test to identify the need for CTA may facilitate clinical management of patients with suspected TOS. Data for patients with suspected arterial TOS who underwent duplex ultrasound with arterial hemodynamic assessment (HDA) (pulse-volume recording and Doppler arterial pressure measurement) at King Saud University Medical City Vascular Lab between 2009 and 2018 were collected. The sensitivity, specificity, positive and negative predictive values (NPV), and area under the curve for duplex ultrasound and arm arterial HDA with CTA were reviewed. The data for 49 patients (mean age, 31 ± 14 years) were reviewed, of which 71% were female. The sensitivity, specificity, positive predictive value, and NPV of duplex ultrasound were 86.7%, 49.3%, 26.5%, and 94.6%, respectively. For arm arterial HDA, these values were 73.3%, 78.9%, 42.3%, and 93.3%, respectively. The combination of arm arterial HDA with duplex ultrasound scores yielded sensitivity, specificity, positive predictive value, and NPV of 93.3%, 42.3%, 25.5%, and 96.8%, respectively. The combination of duplex ultrasound with arm arterial HDA showed higher sensitivity and NPV than either test alone. The specificity of arm arterial HDA was significantly higher than that of the other measurements. When suspected, arterial TOS could be ruled out using duplex ultrasound and arm arterial HDA. These 2 investigations may help determine the need for CTA.

Figure 1.

Number of positive and negative results for limbs tested for arterial thoracic outlet syndrome with computed tomography angiography, duplex ultrasound, and arm arterial hemodynamic assessment. CTA = computed tomography angiography, HAD = hemodynamic assessment, TOS = thoracic outlet syndrome.

Figure 2.

Receiver operating characteristic (ROC) curve for duplex ultrasound with arm arterial hemodynamic assessment score versus computed tomography angiography.

Figure 3.

Sensitivity and negative predictive value for each test and their combination in comparison with computed tomography angiography results (n = 86). HAD = hemodynamic assessment, NPV = negative predictive value, TOS = thoracic outlet syndrome.