Association of Increased Inter-arm Blood Pressure Difference with Long-term Clinical Outcomes in Patients with Acute Myocardial Infarction Who Underwent Percutaneous Coronary Intervention.

Objective Patients with acute myocardial infarction (AMI) often have peripheral artery disease (PAD). It is well known that the long-term clinical outcomes of AMI are worse in patients with a low ankle-brachial index (ABI) than in patients with a preserved ABI. Unlike ABI, the association between the inter-arm blood pressure difference (IABPD) and clinical outcomes in patients with AMI has not yet been established. This retrospective study examined whether or not the IABPD is associated with long-term clinical outcomes in patients with AMI. Methods We included 979 patients with AMI and divided them into a high-IABPD group (IABPD ≥10 mmHg, n=31) and a low-IABPD group (IABPD <10 mmHg, n=948) according to the IABPD measured during hospitalization for AMI. The primary endpoint was the all-cause mortality rate. Results During a median follow-up duration of 694 days (Q1, 296 days; Q3, 1,281 days), 82 all-cause deaths were observed. Kaplan-Meier curves showed that all-cause death was more frequently observed in the high-IABPD group than in the low-IABPD group (p<0.001). A multivariate Cox hazard analysis revealed that a high IABPD was significantly associated with all-cause death (hazard ratio 2.061, 95% confidence interval 1.012-4.197, p=0.046) after controlling for multiple confounding factors. Conclusion A high IABPD was significantly associated with long-term all-cause mortality in patients with AMI. Our results suggest the usefulness of the IABPD as a prognostic marker for patients with AMI.