Heart Murmur Causes & Risks

Causes

Benign heart murmurs are caused by:

• Turbulent blood flow through a highly dynamic but normal circulatory system
• Slight valvular abnormality with no long-term consequences (such as mitral valve prolapse , a congenital condition)

Abnormal heart murmurs can be due to:

• Structural abnormalities of the heart valve (most common):
  • Congenital (present at birth) defects
  • Acquired (eg, arteriosclerosis , rheumatic fever )
• Structural abnormality of the heart muscle:
  • Congenital defects
  • Acquired (eg, myocardial infarction , congestive heart failure , long-standing high blood pressure )
• Abnormal holes in the structure of the heart persisting after birth:
  • Septal defects —connection between the heart's chambers
  • Patent ductus-arteriosus —connection between the major artery and vein of the heart
• Endocarditis —infection of the inner lining of heart valves and chambers (endocardium)
• Pericarditis —inflammation of the saclike membrane that encloses the heart (pericardium). This may be caused by:
  • Severe kidney disease
  • Heart attack
  • Autoimmune disease
• Cardiac myxoma—a benign soft tumor within the heart (rare)

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors for normal heart murmurs include:

• Age: 3-7 years old
• Pregnancy

Risk factors for abnormal heart murmurs include:

• Rheumatic fever
• Arteriosclerosis
• High blood pressure
• Autoimmune disease
• Congenital heart defects or disease