Which term represents the two normal heart sounds that occur in sequence with each heartbeat?

Which term represents the two normal heart sounds that occur in sequence with each heartbeat?

• A. Rub
• B. AAA
• C. Aneurysm
• D. S1S2

Answer: (D)

Two normal heart sounds occur each heartbeat as a result of valve closures. The first sound (S1) is produced when the mitral and tricuspid valves close at the start of systole. The second sound (S2) follows when the aortic and pulmonic valves close at the end of systole. Together, these two sounds are referred to as S1S2, the normal pair heard on auscultation. The other terms describe things unrelated to the normal two sounds of the heartbeat—such as a pericardial friction rub, or vascular conditions like an abdominal aortic aneurysm—so they don’t fit as the term for the two normal heart sounds.

Two normal heart sounds occur each heartbeat as a result of valve closures. The first sound (S1) is produced when the mitral and tricuspid valves close at the start of systole. The second sound (S2) follows when the aortic and pulmonic valves close at the end of systole. Together, these two sounds are referred to as S1S2, the normal pair heard on auscultation. The other terms describe things unrelated to the normal two sounds of the heartbeat—such as a pericardial friction rub, or vascular conditions like an abdominal aortic aneurysm—so they don’t fit as the term for the two normal heart sounds.