General Cardiology Part 6
This would be described as a IV/IV murmur or 4/4 intensity murmur. This describes the intensity, but remember the timing, pitch, location and radiation must be described as well to be complete.
Diastolic murmurs are graded on a scale of 1-4 while systolic murmurs are graded on a scale of 1-6. Often, grade 1 systolic/diastolic murmurs are not discernable to inexperienced clinicians, while grade 4 diastolic or grade 6 systolic murmurs are heard even without the stethoscope on the chest and may actually be visible. The intensity of a murmur is primarily determined by the volume/velocity of blood flowing through a defect and the distance between the stethoscope and the lesion. For example, a very thin patient with severe aortic stenosis with a high pressure gradient across the valve (thus high velocity of blood flow) will have a loud murmur. Conversely, the exact same valvular lesion in a morbidly obese person or a person with severe COPD and a widened anterior-posterior chest diameter may be inaudible.
Grading Diastolic Murmurs
Intensity |
Description |
Grade I |
Barely audible |
Grade II |
Audible, but soft |
Grade III |
Easily audible |
Grade IV |
Loud |