How would you grade a heart murmur that is faint and sometimes cannot be heard when the patient changes positions?

A heart murmur that is faint and may not be audible with changes in the patient's position is classified as a low-grade murmur. The grading scale for heart murmurs typically ranges from I to VI, with I being barely audible and VI being easily heard without a stethoscope, often associated with significant pathology.

A grade I murmur is characterized by its faintness, where it is only detectable in quiet environments and may require careful listening to be heard, especially in different positions. The fact that it can be transient and sometimes inaudible with positional changes further supports its classification as a grade I.

Higher grades, such as II or III, would indicate that the murmur is more easily heard or has a more pronounced quality, which does not match the description of this particular murmur. Therefore, the classification as a grade I murmur is appropriate given its faint nature and variability with position.