Which of the following statements is not true of the location of the heart?

Correct Answer: D

Rationale: All statements about the location of the heart provided here are true.

Correct Answer: D

Rationale: The core measures for the treatment of heart failure established by The Joint Commission indicate that patients with an ejection fraction below 40% should receive an ACE inhibitor to decrease the progression of heart failure. Aerobic exercise may not be appropriate for a patient with this level of heart failure, salt substitutes are not usually recommended because of the risk of hyperkalemia, and the patient will need to see the primary care provider more frequently than annually.

Correct Answer: C

Rationale: The sinoatrial node (SA node) is the pacemaker located in the right atrial wall just inferior to the entrance of the superior vena cava. The SA node generates impulses which travel across the atria (followed by atrial systole) and then pause (0.1s) at the atrioventricular node (AV node, sited at the superior part of the inter-ventricular septum) and then to the bundle of His located between the ventricles, splitting into right and left branches down the inter-ventricular septum towards the heart apex, and out to the Purkinje fibres which turn superiorly into the ventricular walls (followed by ventricular systole).

Correct Answer: B

Rationale: The common carotid artery typically bifurcates into internal and external carotid arteries at the C3-C4 level.

Correct Answer: C

Rationale: The AV bundle (AV node) has the slowest conduction to delay the impulse, allowing atrial contraction before ventricular.