Final answer:
A depolarization wave moving towards a positive chest sensor on an ECG results in a positive or upright deflection on the EKG tracing. Lead II potential is often used as an indicator of heart function, and portable ECG monitors have advanced to provide accessible heart monitoring solutions.
Step-by-step explanation:
Because the electrode sensor for the chest leads is always POSITIVE, a depolarization wave moving toward a given chest sensor produces a positive or upright deflection in that chest lead on the EKG tracing. An electrocardiogram (ECG) records the voltages created by the wave of depolarization and subsequent repolarization of the heart. The lead II potential, often the most graphed, is a measure of the voltage between the right arm and the left leg and serves as an indicator of heart muscle function.
Modern ECGs consist of 12 leads and can provide extensive information about the heart, such as detecting damaged heart tissue, also known as infarcts. Advances in ECG technology have enabled the development of portable ECG monitors with instant displays and printers, making them accessible in various settings including patients' homes and emergency vehicles.