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Real-Time Electrocardiogram Monitoring During Treadmill Training in Mice

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"Giant R wave" electrocardiogram pattern during exercise treadmill test: A case report.

Ana Testa-Fernández¹, Ramón Rios-Vazquez, Juan Sieira-Rodríguez-Moret

¹Department of Cardiology, Hospital Lucus Augusti, San Cibrao s/n, Lugo E-27003, Spain. ana.testa.fernandez@gmail.com.

Journal of Medical Case Reports

|July 13, 2011

Summary

A rare "giant R wave" during an exercise treadmill test indicated severe ischemia. Prompt nitroglycerin administration resolved the issue, highlighting its importance in preventing critical cardiac events.

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Area of Science:

Cardiology
Diagnostic Imaging

Background:

The exercise treadmill test is a standard tool for evaluating coronary artery disease.
ST-segment depression is the typical ischemic response observed.

Purpose of the Study:

To report a rare case of a "giant R wave" pattern as an unusual ischemic response during an exercise treadmill test.
To discuss the clinical implications and management of this dramatic electrocardiogram finding.

Main Methods:

Case report of a 51-year-old man presenting with an unusual ischemic response on exercise treadmill test.
Coronary catheterization to identify the underlying coronary artery pathology.
Treatment with sublingual nitroglycerin and subsequent percutaneous coronary intervention.

Main Results:

The patient exhibited a "giant R wave" pattern, indicative of hyperacute ischemia.
Coronary angiography revealed severe stenosis in a proximal dominant circumflex artery, likely exacerbated by coronary spasm.
The ischemic response resolved rapidly following sublingual nitroglycerin administration.

Conclusions:

The "giant R wave" pattern represents a rare and dramatic manifestation of acute myocardial ischemia during exercise testing.
Early recognition and rapid treatment with nitroglycerin are crucial for preventing potentially life-threatening cardiac events in such cases.