Which conditions can cause a cardiac murmur?

Which conditions can cause a cardiac murmur?

• A. Increased velocity of blood flow during exercise
• B. Decreased viscosity of blood in anemia
• C. Structural defects or unusual openings
• D. All of the above

Answer: (D)

Cardiac murmurs come from turbulent blood flow inside the heart or vessels. Turbulence can arise when flow velocity is high, when blood is less viscous, or when abnormal pathways redirect flow. During exercise, the heart pumps more blood and the velocity of flow increases. This higher speed can disrupt smooth laminar flow and produce a audible sound, even in a healthy person, known as a benign or physiologic murmur. In anemia, blood is less viscous, which lowers resistance to flow. With the same driving pressure, the faster, less resisted flow becomes more prone to turbulence, which can create a murmur. Structural defects or unusual openings, such as holes between chambers or abnormal connections, provide new routes for blood. The resulting turbulent flow across valves or through these openings is a classic source of murmurs. Because each of these scenarios can generate turbulence that the ear detects as a heart murmur, all of the above conditions can cause a murmur.

Cardiac murmurs come from turbulent blood flow inside the heart or vessels. Turbulence can arise when flow velocity is high, when blood is less viscous, or when abnormal pathways redirect flow.

During exercise, the heart pumps more blood and the velocity of flow increases. This higher speed can disrupt smooth laminar flow and produce a audible sound, even in a healthy person, known as a benign or physiologic murmur.

In anemia, blood is less viscous, which lowers resistance to flow. With the same driving pressure, the faster, less resisted flow becomes more prone to turbulence, which can create a murmur.

Structural defects or unusual openings, such as holes between chambers or abnormal connections, provide new routes for blood. The resulting turbulent flow across valves or through these openings is a classic source of murmurs.

Because each of these scenarios can generate turbulence that the ear detects as a heart murmur, all of the above conditions can cause a murmur.