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 μg), nitroglycerin (100 and 200 μg), 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 μg 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 μg, nitroglycerin 100 and 200 μg and after cuff inflation-deflation also demonstrated significant correlation. Receiver operator curve analysis demonstrated that a TLG > or = 11 mmHg post 100 μg 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.