Which test records the heart's electrical activity?

Which test records the heart's electrical activity?

• A. Echocardiogram
• B. Angiogram
• C. Electrocardiogram
• D. Nuclear stress test

Answer: (C)

Recording the heart’s electrical activity is done with an electrocardiogram. By placing small electrodes on the chest and limbs, the device measures the voltage changes produced as the heart’s electrical impulses travel through the heart, giving a tracing of rhythm and conduction (think P wave, QRS complex, and T wave). This makes it especially good for spotting abnormal rhythms, blocks in electrical pathways, and evidence of past or current ischemia. Other tests focus on structure or blood flow rather than electrical signals: echocardiography uses ultrasound to visualize the heart’s size and motion, angiography images the coronary arteries with contrast, and a nuclear stress test looks at blood flow to the heart muscle under stress with a radioactive tracer. So the test that records the heart’s electrical activity is the electrocardiogram.

Recording the heart’s electrical activity is done with an electrocardiogram. By placing small electrodes on the chest and limbs, the device measures the voltage changes produced as the heart’s electrical impulses travel through the heart, giving a tracing of rhythm and conduction (think P wave, QRS complex, and T wave). This makes it especially good for spotting abnormal rhythms, blocks in electrical pathways, and evidence of past or current ischemia. Other tests focus on structure or blood flow rather than electrical signals: echocardiography uses ultrasound to visualize the heart’s size and motion, angiography images the coronary arteries with contrast, and a nuclear stress test looks at blood flow to the heart muscle under stress with a radioactive tracer. So the test that records the heart’s electrical activity is the electrocardiogram.