Faculty Collaboration Database

QT dispersion may be a useful adjunct for detection of myocardial infarction in the chest pain center. Am Heart J 1998 Sep;136(3):496-8

Date

09/15/1998

Pubmed ID

9736143

DOI

10.1016/s0002-8703(98)70226-1

Scopus ID

2-s2.0-0031713350 (requires institutional sign-in at Scopus site)   22 Citations

Abstract

BACKGROUND: QT dispersion has been proposed as a noninvasive measurement of the degree of inhomogeneity in myocardial repolarization. Increased QT dispersion has been reported after myocardial infarction. We hypothesized that increased QT dispersion may be a useful adjunct for risk stratification in patients being evaluated in a chest pain center.

METHODS AND RESULTS: Patients were admitted to the chest pain center for evaluation of chest pain. Exclusion criteria included (1) systolic blood pressure <90 mm Hg, (2) ischemia or infarction on the initial electrocardiograph (ECG), (3) elevated creatine kinase or MB fraction, and (4) chest pain associated with cocaine use. Serial creatine kinase and MB levels and ECGs were obtained at 0, 6, and 9 hours. Patients were monitored for (1) creatine kinase and MB rise, (2) ECG changes for infarction, (3) ST-segment changes, and (4) rest angina. A negative evaluation at the chest pain center led to an exercise stress test. Patients with a positive exercise stress test were admitted for further evaluation and patients with a negative exercise stress test result were discharged home. Patients were divided into 3 groups. Group 1 consisted of patients who were found to have an acute myocardial infarction (AMI), group 2 consisted of patients with prior history of coronary artery disease but no evidence of AMI, and group 3 consisted of patients without prior coronary artery disease or AMI. QT dispersion was measured on the initial ECG in all patients. A total of 586 patients were evaluated. Group 1 consisted of 13 patients with mean QT dispersion of 44.6+/-18.5 ms, group 2 consisted of 267 patients with a mean QT dispersion of 10.0+/-13.8 ms, and group 3 consisted of 303 patients with a mean QT dispersion of 10.5+/-10.0 ms. Analysis of variance showed a significantly higher QT dispersion in patients who had AMI compared with other patients with chest pain (P< .001).

CONCLUSIONS: QT dispersion can be a useful diagnostic adjunct for detection of AMI in patients with chest pain with a normal ECG and normal cardiac enzymes.

Author List

Shah CP, Thakur RK, Reisdorff EJ, Lane E, Aufderheide TP, Hayes OW

Author

Tom P. Aufderheide MD Professor in the Emergency Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Angina Pectoris
Diagnosis, Differential
Electrocardiography
Female
Heart Conduction System
Humans
Male
Middle Aged
Myocardial Infarction
Predictive Value of Tests
Wisconsin