Admission Heart Rate Is Associated With Coronary Artery Disease Severity and Complexity in Patients With Acute Coronary Syndrome.

We evaluated the relationship between admission heart rate (HR) and coronary artery disease severity and complexity in patients with acute coronary syndrome (ACS). A total of 884 patients (mean age 59 [11] years, 24.7% female) who underwent coronary angiography for ACS and were treated with primary or selective percutaneous coronary intervention were included in this cross-sectional study. The measurement of admission HR was based on the first available resting electrocardiogram after admission. The SYNTAX score (SS) was calculated. Patients with an SS ≤ 22 (n = 538) were classified as the low SS group and those with an SS > 22 (n = 346) were classified as the intermediate-to-high SS group. Admission HR was greater in the intermediate-to-high SS group compared with the low SS group (75 [10] bpm vs 67 [8] bpm, P < .001). Admission HR was positively and significantly correlated with the SS (r = 0.475, P < .001). After multivariate analysis, admission HR (per 1 standard deviation, ie, 10 bpm) remained an independent predictor of intermediate-to-high SS (odds ratio: 3.135, 95% confidence interval: 2.538-3.873, P < .001). Admission HR is independently and positively associated with the SS. Thus, elevated admission HR may be useful to identify patients with ACS with a high coronary atherosclerotic plaque burden.