Final answer:
To calculate the heart rate using an ECG, count the number of QRS complexes in 6 seconds and multiply by 10 to estimate the bpm. An increase in the frequency of QRS complexes indicates a higher heart rate.
Step-by-step explanation:
The question pertains to the interpretation of an Electrocardiogram (ECG) which is a common tool used in medicine to assess the electrical and muscular functions of the heart. The QRS complex is a key feature of the ECG representing ventricular depolarization and is crucial for determining heart rate. To calculate the heart rate you would count the number of complete QRS complexes observed on the ECG within a specific time frame (typically 6 seconds for ease of calculation) and then multiply that count by a factor (10 when using a 6-second interval) to extrapolate the number of beats per minute (bpm). If the frequency of QRS complexes increases, indicating more beats in a given time, the heart rate is expected to increase correspondingly.