Olivier CB, et al. - Given a high risk of myocardial infarction (MI) has been reported in patients with peripheral artery disease (PAD), researchers examined a PAD population in order to determine the incidence and types of MI, to identify factors related to MI, and to examine the association of MI with cardiovascular mortality and acute limb ischemia. A median follow-up of 30 months was performed, during which an MI was reported in nearly 5% of patients with symptomatic PAD. The most common MI type was type 1 MI (spontaneous); however, type 2 MI (secondary) was reported in one-third of MIs cases.

Methods

• A double-blind randomized clinical trial, named the Study Comparing Cardiovascular Effects of Ticagrelor and Clopidogrel in Patients With Peripheral Artery Disease (EUCLID), was conducted at 811 sites in 28 countries including 1,3 885 patients with symptomatic PAD, with an ankle-brachial index (ABI) of 0.80 or less or previous lower extremity revascularization.
• Participants were randomized to monotherapy with ticagrelor or clopidogrel and were examined during a median follow-up of 30 months.
• For these analyses, MI occurrence during follow-up was assessed regardless of treatment.
• Data analysis was carried out from June 2017 to September 2018.
• MI was categorized as type 1 (spontaneous), type 2 (secondary), type 3 (sudden cardiac death), type 4a (less than 48 hours after percutaneous coronary intervention), type 4b (definite stent thrombosis), or type 5 (less than 72 hours after coronary artery bypass graft) by an adjudication clinical events committee.
• Factors associated with MI were determined by using a multivariate regression model developed by stepwise selection.
• The association of MI with cardiovascular death and acute limb ischemia requiring hospitalization was determined by performing a time-dependent multivariate Cox regression analysis.

Results

• A total of 13,885 subjects participated, 9997 (72.0%) were male, and the median (interquartile range) age was 66 (60-73) years.
• During a median follow-up of 30 months, the occurrence of myocardial infarction was reported in 683 patients (4.9%; 2.4 events per 100 patient-years).
• Patients experiencing MI vs censored patients showed following features: were older (median [interquartile range] age, 69 [62-75] vs 66 [60-72] years), more likely to have diabetes (349 of 683 [51.1%] vs 4996 of 13 202 [37.8%]) or a previous lower extremity revascularization (466 of 683 [68.2%] vs 7409 of 13 202 [56.1%]), and had a lower ABI (if included by ABI).
• During follow-up, MI was reported in 683 patients, the most common MI type was type 1 (405 [59.3%]), followed by type 2 (236 [34.6%]), type 4a (14 [2.0%]), type 3 (12 [1.8%]), type 4b (11 [1.6%]), and type 5 (5 [0.7%]).
• Findings revealed an independent association of postrandomization MI with cardiovascular death (adjusted hazard ratio, 9.0; 95% CI, 7.3-11.2; P<.001) and acute limb ischemia requiring hospitalization (adjusted hazard ratio, 2.5; 95% CI, 1.3-5.0; P=.008).