Antithrombotic therapy in peripheral artery disease: A review of the EUCLID trial results and current ongoing trials

In addition to risk-factor modification, antithrombotic therapy is the hallmark of management to reduce cardiovascular ischemic events in patients with peripheral artery disease (PAD). Currently, the guidelines recommend long-term antiplatelet therapy with aspirin or clopidogrel in this patient population to reduce myocardial infarction, stroke, and vascular death. Past outcomes studies have shown some benefit of ticagrelor, another antiplatelet agent, as compared with clopidogrel in patients with coronary disease and concomitant PAD. However, most recently, the Examining Use of Ticagrelor in Peripheral Artery Disease (EUCLID) trial has shown no additional benefit of ticagrelor over clopidogrel. In this trial, a minority of patients had concomitant coronary artery disease, making it unique to previous studies. The EUCLID trial's evidence of neutrality between clopidogrel and ticagrelor sheds light into the complexity of studying the PAD population and the continued need to meticulously design trials to investigate the optimal therapies. The topics that will be discussed in this review include the role of antiplatelet therapy in the management of patients with PAD, a review of the EUCLID trial results and the important factors to be considered in interpreting the surprising results, and promising recent ongoing clinical trials assessing therapies in the treatment of patients with PAD.

Ankle Brachial Index Use in Peripheral Vascular Interventions for Claudication

OBJECTIVES

Ankle brachial index (ABI) is recommended as the first-line noninvasive test to establish a diagnosis of peripheral arterial disease (PAD) in claudicants (Grade 1, Level A evidence). It is also used to monitor progression of disease and assess benefit of treatment after peripheral vascular intervention (PVI). The Upper Midwest Region VQI has a unique balance of participation from vascular surgeons, interventional radiologists, and cardiologists performing PVI. We sought to identify the use of ABI and assess functional outcome of patients undergoing PVI for claudication.

METHODS

Review of the Upper Midwest Region VQI registry was performed to identify PVI done for claudication from native artery atherosclerotic occlusive disease in non-diabetic patients from 2010 to 2020. PVI performed in patients with infection, tissue loss, rest pain, bypass graft stenoses, and aneurysmal disease was excluded. Primary outcomes included ABI, ambulation status, and functional status pre- and post-PVI.

RESULTS

A total of 3787 patients (58.0% men, 42.0% female; mean age 68.4 years) who underwent 3830 procedures were identified. 2665 (69.5%) patients had ABI measured: 1803 (47.1%) patients had pre-PVI only, 190 (4.9%) patients had post-PVI only, and 862 (22.5%) patients had pre- and post-PVI ABI measured. 975 (25.5%) patients never had ABI performed. Statistical analysis of all 3787 patients found no change in ambulation (p = 0.33 - 0.95 for all comparisons) or in functional status (p = 0.42 - 0.61 for all comparisons), for all instances of ABI, or lack thereof. A significant number of patients who never had ABI measured decreased from full functional status pre-PVI to only being functional with light work post-PVI (p =0.015).

CONCLUSIONS

Despite Grade 1, level A evidence, ABI was utilized pre- and post-PVI in only 22.5% of patients undergoing PVI for claudication. Importantly, overall functional status was found to diminish significantly after PVI in those patients who never had an ABI performed. Accurately identifying patients with claudication from PAD with an ABI remains critically important before PVI. Given the lack of overall improvement in ambulation post-PVI noted in this study, identifying the patient who will benefit from PVI for claudication remains elusive.