Medline ® Abstract for Reference 7
of 'Electrocardiographic diagnosis of myocardial infarction in the presence of bundle branch block or a paced rhythm'
False-negative and false-positive ECG diagnoses of Q wave myocardial infarction in the presence of right bundle-branch block.
Gussak I, Wright RS, Bjerregaard P, Chaitman BR, Zhou SH, Hammill SC, Kopecky SL
Right bundle-branch block (RBBB) has not traditionally been seen as an obstacle to ECG diagnosis of Q wave myocardial infarction (MI)--in clinical electrocardiography and vectorcardiography--because this conduction disturbance is not believed to cause significant alterations in the spatial orientation of initial excitation wavefronts. In the era of large-scale clinical trials, however, where serial ECG analysis is among the major diagnostic tools in MI classification, both false-positive and false-negative diagnoses of MI in the presence of RBBB have become increasingly evident. Because of the limited detectability of Q wave MI by ECG in the presence of RBBB, the electrocardiographic finding of Q wave MI should not be regarded as an independent diagnostic tool. It is best to utilize independent corroboration to establish the diagnosis of transmural infarction when RBBB is present. Further investigations are warranted to better delineate sensitivity, specificity, and predictive value of Q wave MI in the presence of RBBB.
Mayo Physician Alliance for Clinical Trials, Mayo Clinic (Stabile 5), 150 Third Street SW, Rochester, MN 55902, USA. Gussak-Ihor@mayo.edu