Final answer:
The question addresses the interpretation of an ECG and the effects of abnormalities preceding the QRS complexes. An increased frequency of QRS complexes likely indicates a tachyarrhythmia, which would result in an increase in heart rate.
Step-by-step explanation:
The subject of this question pertains to the interpretation of an electrocardiogram (ECG), specifically relating to the timing and pattern of the QRS complexes which represent ventricular depolarization. If abnormal electrical patterns are noted before the QRS complexes, and the frequency of these complexes has increased, it suggests a potential arrhythmia such as atrial fibrillation or another form of tachyarrhythmia. As a result, the heart rate (pulse) is expected to increase. This is due to the irregular and rapid firing of electrical impulses that cause the ventricles to contract more frequently.
An understanding of ECG components is crucial here: the P wave corresponds to atrial depolarization, the QRS complexes to ventricular depolarization, and the T wave to ventricular repolarization. For example, atrial fibrillation before the QRS complex increases the rate of ventricular contraction, leading to a significantly higher heart rate. Moreover, electrical instabilities like those seen in ventricular tachycardia also impact the QRS complex shape and can dramatically affect heart function and blood pressure dynamics.
Therefore, one would anticipate an increase in the heart rate when there is an increased frequency of QRS complexes and abnormal electrical patterns before them, as the heart is working harder and faster to pump blood through the body.