Ethnic Differences in ST Height in the Multiethnic Study of Atherosclerosis

BACKGROUND: ST elevation in precordial leads has been associated with genetic syndromes of arrhythmias and sudden death. ST height data in different ethnic groups are limited. METHODS: ST height was determined in 4612 African-American, Chinese, Hispanic, and non-Hispanic white men and women aged 45-84 years in the Multiethnic Study of Atherosclerosis (MESA). For leads I, II, and V(1) to V(6,) ST height, measured at the J point and 60 ms after the J point, adjusted for covariates were compared between non-Hispanic white and other ethnic groups using analysis of covariance (ANCOVA). RESULTS: Among men, ST height was significantly different across all ethnic groups at both time points for all leads (P < 0.01), except at the J point for limb lead II (P = 0.2). Among women, differences were also significant at the J point and 60 ms past the J point (P < 0.01). ST height was lowest for non-Hispanic whites in all leads and at both time points. At the J point, Chinese had the highest ST height for leads V(1) and V(2), whereas African Americans had the greatest ST height for leads I and V(3) to V(6). At 60 ms past the J point, Chinese men had the greatest ST height for lead I and V(1) to V(6;) and Chinese women had greatest ST height for leads V(1) to V(3). CONCLUSIONS: There were significant differences in ST height among ethnic groups in all ECG leads. The physiological mechanisms and clinical significance of these differences and the possible association with arrhythmias require further study.