As a medical professional with expertise in cardiology, I can explain the Q wave. In an electrocardiogram (ECG or EKG), the Q wave represents the initial rapid depolarization of the ventricles, which are the lower chambers of the heart. Normally, a Q wave is small and narrow, but it can become more prominent under certain conditions. The presence of a Q wave can be significant in diagnosing various heart conditions. For instance, a Q wave that is too deep or too wide can indicate a previous heart attack, as the dead tissue in the heart (infarcted tissue) does not depolarize, leading to a loss of the R wave and a more prominent Q wave in the ECG. However, it's important to note that the presence of a Q wave alone is not diagnostic of a heart attack; it must be evaluated within the context of the entire ECG pattern and the patient's clinical history. read more >>

By definition, a Q wave on the electrocardiogram (ECG) is an initially negative deflection of the QRS complex. Technically, a Q wave indicates that the net direction of early ventricular depolarization (QRS) electrical forces projects toward the negative pole of the lead axis in question.read more >>