ECG Waveforms and Heart Function

These flashcards cover key concepts related to ECG waveforms, heart function, blood flow, and respiratory volumes that are essential for understanding cardiac and respiratory physiology.

What does the P wave represent in an ECG?

The P wave represents atrial depolarization, which is when the atria contract.

What is the PR interval in an ECG?

The PR interval is the time from the start of the P wave to the start of the Q wave, indicating the delay as the signal moves from the atria to the ventricles.

What does the QRS complex indicate?

The QRS complex indicates ventricular depolarization, which is when the ventricles contract.

What is indicated by an elevated ST segment?

An elevated ST segment may indicate a heart attack, also known as a myocardial infarction.

What happens during systole?

During systole, the ventricles contract and blood is pumped out of the heart.

What does the T wave represent?

The T wave represents ventricular repolarization, which resets the ventricles for the next beat.

What is the RR interval?

The RR interval is the time between heartbeats.

What changes occur in the heart during inhalation?

During inhalation, the heart rate slightly increases due to increased pressure in the chest that draws more blood into the heart.

What anatomical structure does blood flow through starting from the body?

Blood flows from the body into the vena cava, then to the right atrium, through the tricuspid valve to the right ventricle, to the pulmonary veins, lungs, left atrium, mitral valve, left ventricle, and finally to the aorta to the rest of the body.

What causes the first heart sound (lub)?

The first heart sound (lub) is caused by the closure of the AV valves at the start of systole.

What are Korotkoff sounds?

Korotkoff sounds are the sounds heard when measuring blood pressure, with the first sound indicating systolic pressure and disappearance indicating diastolic pressure.

What is the difference between vital capacity and FEV?

Vital capacity (VC) is the maximum amount of air exhaled after a full inhale, while forced expiratory volume (FEV) is how fast air can be blown out.

What affects lung capacity?

Lung capacity can be affected by age, smoking, and diseases such as COPD, leading to less air being inhaled and exhaled.