Physical Examination: Difference between revisions

====Murmurs categorized by time in cardiac cycle====

A schematic scheme of the heart sounds and heart murmurs are shown in Figure 5.

   

'''Systolic murmurs''' are very common and do not always imply cardiac disease. Most murmurs fall in the 1–3 audible intensity range, however murmurs in the 4–6 range are almost always due to pathologic conditions. Again, severe disease can exist with grades 1–3 or no cardiac murmurs. Distinguishing benign from pathologic systolic flow murmurs is one of the major challenges of clinical cardiology. Benign flow murmurs are heard in 80% of children with a declining incidence with increasing age. Other physical conditions known for benign heart systolic murmurs are pregnancy or thin adults or athletic adults. The murmur is usually benign in a patient with a soft flow murmur that diminishes in intensity in the sitting position and neither a history of cardiovascular disease nor other cardiac findings. The physiological flow murmurs are usually heard in grades 1–2 and occur very early in systole. These murmurs have a vibratory quality and are usually less apparent when the patient is in the sitting position (when venous return is less). If an ejection sound is heard, there is usually some abnormality of the aortic or pulmonary valve. The most common systolic murmur is the becoming stronger and fading (crescendo/decrescendo) murmur. This murmur increases in intensity as blood flows early in systole and diminishes in intensity through the second half of systole. This murmur can be caused by a strong flow in a normal heart or to obstructions of flow, as occurs with a stenotic semilunar valve, or hypertrophic cardiomyopathy.