"Abnormal" electrocardiograms in patients with cocaine-associated chest pain are due to "normal" variants.

"Abnormal" electrocardiograms are found in 56% to 84% of patients with cocaine-associated chest pain. This study was designed to assess whether these findings can be explained by "normal" variations in young patients' electrocardiograms. This cross-sectional study was conducted in a municipal hospital emergency department and walk-in clinic. History and results of an electrocardiogram for consecutive patients with cocaine-associated chest pain, aged 18 to 35 years, were compared to normal controls matched for age, race, and gender. Electrocardiograms underwent detailed analysis by two physicians blinded to both the study protocol and the hypothesis. Interphysician concordance for electrocardiographic diagnosis was substantial. There were 112 patients enrolled, 56 in each group. There was no significant difference found in the mean frequency of electrocardiographic diagnoses between the cocaine-associated chest pain patients and controls. The early repolarization variant was common. In conclusion, "normal" variations (J point and ST segment elevations) account for many of the "abnormal" electrocardiograms observed in young patients with cocaine-associated chest pain. Further study is needed to define the prevalence of these "normal" variations, and to determine if standard electrocardiographic criteria for thrombolysis apply to young patients.