ATI RN
Cardiovascular System Test Questions Questions
Question 1 of 5
The reason for the dicrotic notch on the aortic pressure curve is
Correct Answer: B
Rationale: The dicrotic notch is a small dip in the aortic pressure curve caused by the closure of the aortic valve at the end of systole, as blood briefly rebounds against it. Aortic contraction doesn’t occur, ventricular filling is diastolic, and pulmonary valve closure affects pulmonary pressure, not aortic.
Question 2 of 5
Which of the following events is the first to take place in a cardiac cycle?
Correct Answer: A
Rationale: The cardiac cycle begins with SA node depolarization (A), initiating the impulse that spreads across the atria (P wave, C), reaches the AV node (B), and then ventricles (QRS, D). SA node firing is the first event.
Question 3 of 5
What structures in the heart wall prevent the AV (atrioventricular) valves from opening up into the atria?
Correct Answer: A
Rationale: Papillary muscles (A) contract to pull chordae tendineae, preventing AV valves from inverting into atria during ventricular systole. Auricles (B) are atrial structures, the septum (C) separates ventricles, and endocardium (D) is a lining.
Question 4 of 5
A heart rate of less than 60 beats per minute is called
Correct Answer: D
Rationale: Bradycardia (D) is a heart rate <60 bpm. Heart block (A) is a conduction issue, tachycardia (B) is >100 bpm, and fibrillation (C) is uncoordinated beating.
Question 5 of 5
Contraction of skeletal muscles will ___ venous return, thus ___ stroke volume.
Correct Answer: C
Rationale: Skeletal muscle contraction (muscle pump) compresses veins, increasing venous return (C), which increases preload and stroke volume per Frank-Starling’s law. A, B, D mismatch effects.