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Updated: Jul 10, 2026

In Vivo Surface Electrocardiography for Adult Zebrafish
Published on: August 1, 2019
The challenge of inferior Q waves
1Ross MacKenzie Consulting, 2261 Constance Drive, Oakville, Ontario L6J 5L8, Canada. rossmackenzieconsulting@msn.com
Abstract:
The presence of unexpected Q waves in an applicant's electrocardiogram poses a diagnostic dilemma for the medical director. On the one hand, the Q waves may be the remnants of a previously unsuspected "silent" myocardial infarction. Conversely, unexpected Q waves may represent a normal or positional variant, or an important noncoronary type of heart disease. This case study illustrates some of the pitfalls in interpreting applicants' electrocardiograms containing Q waves in the inferior leads.
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