Objectives:
Peripheral vascular disease (PVD) is a systemic disorder, which can affect all territories of arteries. In order to maximize screening survey yield: we aimed to describe the association between positive lower extremity (LE) non-invasive flow studies in symptomatic patients and occult carotid occlusive disease (COD).
Methods:
A retrospective chart review was performed on 420 patients who underwent carotid duplex ultrasound and non-invasive flow studies (NIFS; aka Pulse volume recordings) for evaluation of COD and LE PVD respectively. Additional clinical variables collected included age, gender, and indication for NIFS and indication for carotid duplex. The respective studies were performed within a year of each other. Statistical analysis was performed using SPSSv20 software and SAS statistical software. Univariate analysis was performed using Mann-Whitney, student t-test and receiver operating curve (ROC).
Results:
66% (266/420) of the patients were male and 43% (181/420) of patients had documented history of bruit. Patients with mild PVD (ABI between 0.81 and 1) were more likely to have clinically significant COD than patients with moderate to severe PVD (ABI < 0.8) (25% vs 16.19%, P=0.03). Therefore, severity of peripheral vascular disease did not correlate with likelihood of clinically significant COD (p>0.05). ROC analysis was performed (AUC=0.602, p=0.05). Low ABI 0.50 was found to be 92% sensitive (Se) but only 14% specific (Sp). The optimal ABI cutoff point for predicting COD was 0.95 (Se=40%,Sp 60%, Youden’s index 0.194)
Conclusion:
Therefore, routine screening for COD in patients with lower extremity peripheral vascular disease is unlikely to uncover clinically significant carotid stenosis. These findings do not indicate a population of patients for which a combined prospective screening is warranted.
An audit of vascular surgery experience at North Surgical Unit, Mayo Hospital Lahore