Cardiac murmurs are abnormal heart sounds that are heard during a cardiac exam. These sounds can be caused by a variety of conditions, including heart valve abnormalities, congenital heart defects, and other structural abnormalities of the heart. Cardiac murmurs can be divided into two categories: systolic murmurs and diastolic murmurs.
Systolic murmurs are heard during the contraction phase of the heart's cycle. These murmurs can be caused by a number of conditions, including aortic stenosis, mitral regurgitation, and ventricular septal defect. Aortic stenosis is a condition in which the aortic valve becomes narrow, causing blood to flow through the valve more quickly and creating a turbulence that produces a murmur. Mitral regurgitation is a condition in which the mitral valve does not close properly, allowing blood to flow back into the left atrium and creating a murmur. Ventricular septal defect is a congenital heart defect in which there is a hole in the wall that separates the two ventricles, allowing blood to flow between them and creating a murmur.
Diastolic murmurs are heard during the relaxation phase of the heart's cycle. These murmurs can be caused by a number of conditions, including aortic regurgitation, mitral stenosis, and tricuspid regurgitation. Aortic regurgitation is a condition in which the aortic valve does not close properly, allowing blood to flow back into the left ventricle and creating a murmur. Mitral stenosis is a condition in which the mitral valve becomes narrow, causing blood to flow through the valve more slowly and creating a turbulence that produces a murmur. Tricuspid regurgitation is a condition in which the tricuspid valve does not close properly, allowing blood to flow back into the right atrium and creating a murmur.
In addition to cardiac murmurs, there are other abnormal heart sounds that can be heard during a cardiac exam. These sounds include clicks, snaps, and rubs.