Clinical approach to cardiac murmurs

The practice of cardiac auscultation remains one of the most widely used diagnostic techniques in veterinary medicine. Technical considerations of cardiac auscultation and interpretation of heart sounds and murmurs are therefore of wide interest to the veterinary practitioner. Although it may not be possible to establish the diagnosis of a specific heart disease with the sole use of a stethoscope, or in combination with a phonocardiogram (PCG), optimal use can narrow down the list of differential diagnoses substantially. A gentle approach and quiet environment are essential for the animal to relax and for the auscultator to be undisturbed. It is also essential to auscultate all cardiac areas to detect local murmurs and, in the case of a heart murmur, the point of maximum intensity (PMI). The chapter covers Stethoscopes; Origin of murmurs; Auscultation and the point of maximum intensity; and the Differential diagnoses for different cardiac murmurs.