ATI RN
100 Questions on the Cardiovascular System Questions
Question 1 of 5
When the bundle of His is completely interrupted, the:
Correct Answer: B
Rationale: If the bundle of His is interrupted (complete heart block), the ventricles beat independently at their intrinsic rate (30-40 beats/min) via Purkinje fibers, while the atria follow the SA node. PR intervals become inconsistent, and QRS shape remains stable unless further complications arise.
Question 2 of 5
The parents of a newborn with a congenital heart disease ask the nurse what is meant by the diagnosis patent ductus arteriosus. The nurse's best explanation includes that this structure is a shunt between the:
Correct Answer: B
Rationale: The ductus arteriosus is a shunt that allows blood to bypass the undeveloped lungs of the fetus by allowing blood to pass between the pulmonary trunk and the aorta (great vessels). This structure closes soon after birth and is replaced by the ligamentum arteriosum. The foramen ovale is the bypass that allows blood to pass through the atria. There is no shunt within the ventricles. (Source: Document, Pretest Answer 3, p. 76)
Question 3 of 5
A cardiovascular assessment on a client's chart notes 'S₁/S₂ audible.' The nurse knows that S₁ is produced by which valves?
Correct Answer: A
Rationale: S₁ ('lub') is produced by the closure of the atrioventricular valves—tricuspid and mitral—at the start of ventricular systole. S₂ ('dub') is from the aortic and pulmonic valves. (Source: Document, p. 62, Valve sounds)
Question 4 of 5
For blood clotting to occur normally:
Correct Answer: D
Rationale: Vitamin K is essential for the liver to synthesize clotting factors (e.g., II, VII, IX, X). Heparin inactivation aids but isn’t required, vitamin C is unrelated, and tissue damage triggers extrinsic clotting but isn’t always necessary.
Question 5 of 5
The blanket term for reactions that prevent or minimize loss of blood from the vessels if they are injured or ruptured is:
Correct Answer: D
Rationale: Hemostasis is the process of stopping blood loss via vasoconstriction, platelet plugs, and clotting. Homeostasis is broader (body equilibrium), and syneresis is clot shrinkage, not the full process.