Relationship of walking impairment and ankle-brachial index assessments with peripheral arterial translesional pressure gradients

Background: The relationship of peripheral arterial mean translesional pressure gradient (TLG) to presenting symptom, functional impairment, and initial noninvasive ABI assessments has never been established. OBJECTIVES: To evaluate the association between TLG, severity of walking impairment, rest and exercise ankle-brachial indices (ABI). METHODS: TLG in 19 patients presenting with claudication and single superficial femoral artery lesion were measured invasively. TLG was measured at rest and post-hyperemia induction with intra-arterial adenosine (100 and 200 g), nitroglycerin (100 and 200 g), and after 3 minutes of ipsilateral calf cuff pressure inflation-deflation sequence. For each patient, a walking impairment questionnaire (WIQ) was completed and rest and exercise ABI were measured prior to TLG assessment. RESULTS: Mean age was 60 ± 6 years, 89 were men. Mean WIQ score was 4817 ± 3549, mean rest and exercise ABI were 0.79 ± 0.14 and 0.59 ± 0.17, respectively, and mean exercise duration was 6.3 ± 3.4 minutes. TLG with 100 g of adenosine strongly correlates with WIQ score (r ≤-0.723); rest ABI (r ≤-0.748); exercise ABI (r ≤-0.888), exercise duration (r ≤-0.711), and percent angiographic stenosis (r ≤-0.818), respectively (p < 0.01 for all). TLG with adenosine 200 g, nitroglycerin 100 and 200 g and after cuff inflation-deflation also demonstrated significant correlation. Receiver operator curve analysis demonstrated that a TLG > or ≤ 11 mmHg post 100 g adenosine administration had 71.43 sensitivity and 100 specificity for identifying patients with disease defining state of exercise ABI < or ≤ 0.70. CONCLUSION: This study validates the utility of invasive TLG measurements using vasodilation for determining the functional and hemodynamic significance of superficial femoral artery lesions.